3514 строки
88 KiB
C
3514 строки
88 KiB
C
/* SPDX-License-Identifier: GPL-2.0 */
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/* Copyright (c) 2018 Facebook */
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#include <uapi/linux/btf.h>
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#include <uapi/linux/types.h>
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#include <linux/seq_file.h>
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#include <linux/compiler.h>
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#include <linux/ctype.h>
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#include <linux/errno.h>
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#include <linux/slab.h>
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#include <linux/anon_inodes.h>
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#include <linux/file.h>
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#include <linux/uaccess.h>
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#include <linux/kernel.h>
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#include <linux/idr.h>
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#include <linux/sort.h>
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#include <linux/bpf_verifier.h>
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#include <linux/btf.h>
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/* BTF (BPF Type Format) is the meta data format which describes
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* the data types of BPF program/map. Hence, it basically focus
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* on the C programming language which the modern BPF is primary
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* using.
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*
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* ELF Section:
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* ~~~~~~~~~~~
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* The BTF data is stored under the ".BTF" ELF section
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*
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* struct btf_type:
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* ~~~~~~~~~~~~~~~
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* Each 'struct btf_type' object describes a C data type.
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* Depending on the type it is describing, a 'struct btf_type'
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* object may be followed by more data. F.e.
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* To describe an array, 'struct btf_type' is followed by
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* 'struct btf_array'.
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*
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* 'struct btf_type' and any extra data following it are
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* 4 bytes aligned.
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*
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* Type section:
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* ~~~~~~~~~~~~~
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* The BTF type section contains a list of 'struct btf_type' objects.
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* Each one describes a C type. Recall from the above section
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* that a 'struct btf_type' object could be immediately followed by extra
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* data in order to desribe some particular C types.
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*
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* type_id:
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* ~~~~~~~
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* Each btf_type object is identified by a type_id. The type_id
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* is implicitly implied by the location of the btf_type object in
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* the BTF type section. The first one has type_id 1. The second
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* one has type_id 2...etc. Hence, an earlier btf_type has
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* a smaller type_id.
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*
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* A btf_type object may refer to another btf_type object by using
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* type_id (i.e. the "type" in the "struct btf_type").
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*
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* NOTE that we cannot assume any reference-order.
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* A btf_type object can refer to an earlier btf_type object
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* but it can also refer to a later btf_type object.
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*
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* For example, to describe "const void *". A btf_type
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* object describing "const" may refer to another btf_type
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* object describing "void *". This type-reference is done
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* by specifying type_id:
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*
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* [1] CONST (anon) type_id=2
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* [2] PTR (anon) type_id=0
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*
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* The above is the btf_verifier debug log:
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* - Each line started with "[?]" is a btf_type object
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* - [?] is the type_id of the btf_type object.
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* - CONST/PTR is the BTF_KIND_XXX
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* - "(anon)" is the name of the type. It just
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* happens that CONST and PTR has no name.
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* - type_id=XXX is the 'u32 type' in btf_type
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*
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* NOTE: "void" has type_id 0
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*
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* String section:
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* ~~~~~~~~~~~~~~
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* The BTF string section contains the names used by the type section.
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* Each string is referred by an "offset" from the beginning of the
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* string section.
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*
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* Each string is '\0' terminated.
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*
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* The first character in the string section must be '\0'
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* which is used to mean 'anonymous'. Some btf_type may not
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* have a name.
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*/
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/* BTF verification:
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*
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* To verify BTF data, two passes are needed.
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*
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* Pass #1
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* ~~~~~~~
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* The first pass is to collect all btf_type objects to
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* an array: "btf->types".
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*
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* Depending on the C type that a btf_type is describing,
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* a btf_type may be followed by extra data. We don't know
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* how many btf_type is there, and more importantly we don't
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* know where each btf_type is located in the type section.
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*
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* Without knowing the location of each type_id, most verifications
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* cannot be done. e.g. an earlier btf_type may refer to a later
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* btf_type (recall the "const void *" above), so we cannot
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* check this type-reference in the first pass.
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*
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* In the first pass, it still does some verifications (e.g.
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* checking the name is a valid offset to the string section).
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*
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* Pass #2
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* ~~~~~~~
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* The main focus is to resolve a btf_type that is referring
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* to another type.
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*
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* We have to ensure the referring type:
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* 1) does exist in the BTF (i.e. in btf->types[])
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* 2) does not cause a loop:
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* struct A {
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* struct B b;
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* };
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*
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* struct B {
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* struct A a;
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* };
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*
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* btf_type_needs_resolve() decides if a btf_type needs
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* to be resolved.
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*
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* The needs_resolve type implements the "resolve()" ops which
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* essentially does a DFS and detects backedge.
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*
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* During resolve (or DFS), different C types have different
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* "RESOLVED" conditions.
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*
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* When resolving a BTF_KIND_STRUCT, we need to resolve all its
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* members because a member is always referring to another
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* type. A struct's member can be treated as "RESOLVED" if
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* it is referring to a BTF_KIND_PTR. Otherwise, the
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* following valid C struct would be rejected:
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*
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* struct A {
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* int m;
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* struct A *a;
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* };
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*
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* When resolving a BTF_KIND_PTR, it needs to keep resolving if
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* it is referring to another BTF_KIND_PTR. Otherwise, we cannot
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* detect a pointer loop, e.g.:
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* BTF_KIND_CONST -> BTF_KIND_PTR -> BTF_KIND_CONST -> BTF_KIND_PTR +
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* ^ |
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* +-----------------------------------------+
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*
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*/
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#define BITS_PER_U128 (sizeof(u64) * BITS_PER_BYTE * 2)
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#define BITS_PER_BYTE_MASK (BITS_PER_BYTE - 1)
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#define BITS_PER_BYTE_MASKED(bits) ((bits) & BITS_PER_BYTE_MASK)
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#define BITS_ROUNDDOWN_BYTES(bits) ((bits) >> 3)
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#define BITS_ROUNDUP_BYTES(bits) \
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(BITS_ROUNDDOWN_BYTES(bits) + !!BITS_PER_BYTE_MASKED(bits))
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#define BTF_INFO_MASK 0x8f00ffff
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#define BTF_INT_MASK 0x0fffffff
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#define BTF_TYPE_ID_VALID(type_id) ((type_id) <= BTF_MAX_TYPE)
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#define BTF_STR_OFFSET_VALID(name_off) ((name_off) <= BTF_MAX_NAME_OFFSET)
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/* 16MB for 64k structs and each has 16 members and
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* a few MB spaces for the string section.
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* The hard limit is S32_MAX.
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*/
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#define BTF_MAX_SIZE (16 * 1024 * 1024)
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#define for_each_member(i, struct_type, member) \
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for (i = 0, member = btf_type_member(struct_type); \
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i < btf_type_vlen(struct_type); \
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i++, member++)
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#define for_each_member_from(i, from, struct_type, member) \
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for (i = from, member = btf_type_member(struct_type) + from; \
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i < btf_type_vlen(struct_type); \
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i++, member++)
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#define for_each_vsi(i, struct_type, member) \
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for (i = 0, member = btf_type_var_secinfo(struct_type); \
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i < btf_type_vlen(struct_type); \
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i++, member++)
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#define for_each_vsi_from(i, from, struct_type, member) \
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for (i = from, member = btf_type_var_secinfo(struct_type) + from; \
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i < btf_type_vlen(struct_type); \
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i++, member++)
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DEFINE_IDR(btf_idr);
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DEFINE_SPINLOCK(btf_idr_lock);
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struct btf {
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void *data;
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struct btf_type **types;
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u32 *resolved_ids;
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u32 *resolved_sizes;
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const char *strings;
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void *nohdr_data;
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struct btf_header hdr;
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u32 nr_types;
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u32 types_size;
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u32 data_size;
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refcount_t refcnt;
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u32 id;
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struct rcu_head rcu;
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};
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enum verifier_phase {
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CHECK_META,
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CHECK_TYPE,
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};
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struct resolve_vertex {
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const struct btf_type *t;
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u32 type_id;
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u16 next_member;
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};
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enum visit_state {
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NOT_VISITED,
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VISITED,
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RESOLVED,
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};
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enum resolve_mode {
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RESOLVE_TBD, /* To Be Determined */
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RESOLVE_PTR, /* Resolving for Pointer */
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RESOLVE_STRUCT_OR_ARRAY, /* Resolving for struct/union
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* or array
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*/
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};
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#define MAX_RESOLVE_DEPTH 32
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struct btf_sec_info {
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u32 off;
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u32 len;
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};
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struct btf_verifier_env {
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struct btf *btf;
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u8 *visit_states;
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struct resolve_vertex stack[MAX_RESOLVE_DEPTH];
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struct bpf_verifier_log log;
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u32 log_type_id;
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u32 top_stack;
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enum verifier_phase phase;
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enum resolve_mode resolve_mode;
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};
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static const char * const btf_kind_str[NR_BTF_KINDS] = {
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[BTF_KIND_UNKN] = "UNKNOWN",
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[BTF_KIND_INT] = "INT",
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[BTF_KIND_PTR] = "PTR",
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[BTF_KIND_ARRAY] = "ARRAY",
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[BTF_KIND_STRUCT] = "STRUCT",
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[BTF_KIND_UNION] = "UNION",
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[BTF_KIND_ENUM] = "ENUM",
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[BTF_KIND_FWD] = "FWD",
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[BTF_KIND_TYPEDEF] = "TYPEDEF",
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[BTF_KIND_VOLATILE] = "VOLATILE",
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[BTF_KIND_CONST] = "CONST",
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[BTF_KIND_RESTRICT] = "RESTRICT",
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[BTF_KIND_FUNC] = "FUNC",
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[BTF_KIND_FUNC_PROTO] = "FUNC_PROTO",
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[BTF_KIND_VAR] = "VAR",
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[BTF_KIND_DATASEC] = "DATASEC",
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};
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struct btf_kind_operations {
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s32 (*check_meta)(struct btf_verifier_env *env,
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const struct btf_type *t,
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u32 meta_left);
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int (*resolve)(struct btf_verifier_env *env,
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const struct resolve_vertex *v);
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int (*check_member)(struct btf_verifier_env *env,
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const struct btf_type *struct_type,
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const struct btf_member *member,
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const struct btf_type *member_type);
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int (*check_kflag_member)(struct btf_verifier_env *env,
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const struct btf_type *struct_type,
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const struct btf_member *member,
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const struct btf_type *member_type);
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void (*log_details)(struct btf_verifier_env *env,
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const struct btf_type *t);
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void (*seq_show)(const struct btf *btf, const struct btf_type *t,
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u32 type_id, void *data, u8 bits_offsets,
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struct seq_file *m);
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};
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static const struct btf_kind_operations * const kind_ops[NR_BTF_KINDS];
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static struct btf_type btf_void;
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static int btf_resolve(struct btf_verifier_env *env,
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const struct btf_type *t, u32 type_id);
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static bool btf_type_is_modifier(const struct btf_type *t)
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{
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/* Some of them is not strictly a C modifier
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* but they are grouped into the same bucket
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* for BTF concern:
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* A type (t) that refers to another
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* type through t->type AND its size cannot
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* be determined without following the t->type.
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*
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* ptr does not fall into this bucket
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* because its size is always sizeof(void *).
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*/
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switch (BTF_INFO_KIND(t->info)) {
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case BTF_KIND_TYPEDEF:
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case BTF_KIND_VOLATILE:
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case BTF_KIND_CONST:
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case BTF_KIND_RESTRICT:
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return true;
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}
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return false;
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}
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bool btf_type_is_void(const struct btf_type *t)
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{
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return t == &btf_void;
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}
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static bool btf_type_is_fwd(const struct btf_type *t)
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{
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return BTF_INFO_KIND(t->info) == BTF_KIND_FWD;
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}
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static bool btf_type_is_func(const struct btf_type *t)
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{
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return BTF_INFO_KIND(t->info) == BTF_KIND_FUNC;
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}
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static bool btf_type_is_func_proto(const struct btf_type *t)
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{
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return BTF_INFO_KIND(t->info) == BTF_KIND_FUNC_PROTO;
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}
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static bool btf_type_nosize(const struct btf_type *t)
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{
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return btf_type_is_void(t) || btf_type_is_fwd(t) ||
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btf_type_is_func(t) || btf_type_is_func_proto(t);
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}
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static bool btf_type_nosize_or_null(const struct btf_type *t)
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{
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return !t || btf_type_nosize(t);
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}
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/* union is only a special case of struct:
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* all its offsetof(member) == 0
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*/
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static bool btf_type_is_struct(const struct btf_type *t)
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{
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u8 kind = BTF_INFO_KIND(t->info);
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return kind == BTF_KIND_STRUCT || kind == BTF_KIND_UNION;
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}
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static bool __btf_type_is_struct(const struct btf_type *t)
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{
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return BTF_INFO_KIND(t->info) == BTF_KIND_STRUCT;
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}
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static bool btf_type_is_array(const struct btf_type *t)
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{
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return BTF_INFO_KIND(t->info) == BTF_KIND_ARRAY;
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}
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static bool btf_type_is_ptr(const struct btf_type *t)
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{
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return BTF_INFO_KIND(t->info) == BTF_KIND_PTR;
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}
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static bool btf_type_is_int(const struct btf_type *t)
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{
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return BTF_INFO_KIND(t->info) == BTF_KIND_INT;
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}
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static bool btf_type_is_var(const struct btf_type *t)
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{
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return BTF_INFO_KIND(t->info) == BTF_KIND_VAR;
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}
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static bool btf_type_is_datasec(const struct btf_type *t)
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{
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return BTF_INFO_KIND(t->info) == BTF_KIND_DATASEC;
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}
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/* Types that act only as a source, not sink or intermediate
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* type when resolving.
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*/
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static bool btf_type_is_resolve_source_only(const struct btf_type *t)
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{
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return btf_type_is_var(t) ||
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btf_type_is_datasec(t);
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}
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/* What types need to be resolved?
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*
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* btf_type_is_modifier() is an obvious one.
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*
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* btf_type_is_struct() because its member refers to
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* another type (through member->type).
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*
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* btf_type_is_var() because the variable refers to
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* another type. btf_type_is_datasec() holds multiple
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* btf_type_is_var() types that need resolving.
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*
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* btf_type_is_array() because its element (array->type)
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* refers to another type. Array can be thought of a
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* special case of struct while array just has the same
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* member-type repeated by array->nelems of times.
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*/
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static bool btf_type_needs_resolve(const struct btf_type *t)
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{
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return btf_type_is_modifier(t) ||
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btf_type_is_ptr(t) ||
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btf_type_is_struct(t) ||
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btf_type_is_array(t) ||
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btf_type_is_var(t) ||
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btf_type_is_datasec(t);
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}
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/* t->size can be used */
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static bool btf_type_has_size(const struct btf_type *t)
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{
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switch (BTF_INFO_KIND(t->info)) {
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case BTF_KIND_INT:
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case BTF_KIND_STRUCT:
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case BTF_KIND_UNION:
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case BTF_KIND_ENUM:
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case BTF_KIND_DATASEC:
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return true;
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}
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return false;
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}
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static const char *btf_int_encoding_str(u8 encoding)
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{
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if (encoding == 0)
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return "(none)";
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else if (encoding == BTF_INT_SIGNED)
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return "SIGNED";
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else if (encoding == BTF_INT_CHAR)
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return "CHAR";
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else if (encoding == BTF_INT_BOOL)
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return "BOOL";
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else
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return "UNKN";
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}
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static u16 btf_type_vlen(const struct btf_type *t)
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{
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return BTF_INFO_VLEN(t->info);
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}
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static bool btf_type_kflag(const struct btf_type *t)
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{
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return BTF_INFO_KFLAG(t->info);
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}
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static u32 btf_member_bit_offset(const struct btf_type *struct_type,
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const struct btf_member *member)
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{
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return btf_type_kflag(struct_type) ? BTF_MEMBER_BIT_OFFSET(member->offset)
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: member->offset;
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}
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static u32 btf_member_bitfield_size(const struct btf_type *struct_type,
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const struct btf_member *member)
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{
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return btf_type_kflag(struct_type) ? BTF_MEMBER_BITFIELD_SIZE(member->offset)
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: 0;
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}
|
|
|
|
static u32 btf_type_int(const struct btf_type *t)
|
|
{
|
|
return *(u32 *)(t + 1);
|
|
}
|
|
|
|
static const struct btf_array *btf_type_array(const struct btf_type *t)
|
|
{
|
|
return (const struct btf_array *)(t + 1);
|
|
}
|
|
|
|
static const struct btf_member *btf_type_member(const struct btf_type *t)
|
|
{
|
|
return (const struct btf_member *)(t + 1);
|
|
}
|
|
|
|
static const struct btf_enum *btf_type_enum(const struct btf_type *t)
|
|
{
|
|
return (const struct btf_enum *)(t + 1);
|
|
}
|
|
|
|
static const struct btf_var *btf_type_var(const struct btf_type *t)
|
|
{
|
|
return (const struct btf_var *)(t + 1);
|
|
}
|
|
|
|
static const struct btf_var_secinfo *btf_type_var_secinfo(const struct btf_type *t)
|
|
{
|
|
return (const struct btf_var_secinfo *)(t + 1);
|
|
}
|
|
|
|
static const struct btf_kind_operations *btf_type_ops(const struct btf_type *t)
|
|
{
|
|
return kind_ops[BTF_INFO_KIND(t->info)];
|
|
}
|
|
|
|
static bool btf_name_offset_valid(const struct btf *btf, u32 offset)
|
|
{
|
|
return BTF_STR_OFFSET_VALID(offset) &&
|
|
offset < btf->hdr.str_len;
|
|
}
|
|
|
|
static bool __btf_name_char_ok(char c, bool first, bool dot_ok)
|
|
{
|
|
if ((first ? !isalpha(c) :
|
|
!isalnum(c)) &&
|
|
c != '_' &&
|
|
((c == '.' && !dot_ok) ||
|
|
c != '.'))
|
|
return false;
|
|
return true;
|
|
}
|
|
|
|
static bool __btf_name_valid(const struct btf *btf, u32 offset, bool dot_ok)
|
|
{
|
|
/* offset must be valid */
|
|
const char *src = &btf->strings[offset];
|
|
const char *src_limit;
|
|
|
|
if (!__btf_name_char_ok(*src, true, dot_ok))
|
|
return false;
|
|
|
|
/* set a limit on identifier length */
|
|
src_limit = src + KSYM_NAME_LEN;
|
|
src++;
|
|
while (*src && src < src_limit) {
|
|
if (!__btf_name_char_ok(*src, false, dot_ok))
|
|
return false;
|
|
src++;
|
|
}
|
|
|
|
return !*src;
|
|
}
|
|
|
|
/* Only C-style identifier is permitted. This can be relaxed if
|
|
* necessary.
|
|
*/
|
|
static bool btf_name_valid_identifier(const struct btf *btf, u32 offset)
|
|
{
|
|
return __btf_name_valid(btf, offset, false);
|
|
}
|
|
|
|
static bool btf_name_valid_section(const struct btf *btf, u32 offset)
|
|
{
|
|
return __btf_name_valid(btf, offset, true);
|
|
}
|
|
|
|
static const char *__btf_name_by_offset(const struct btf *btf, u32 offset)
|
|
{
|
|
if (!offset)
|
|
return "(anon)";
|
|
else if (offset < btf->hdr.str_len)
|
|
return &btf->strings[offset];
|
|
else
|
|
return "(invalid-name-offset)";
|
|
}
|
|
|
|
const char *btf_name_by_offset(const struct btf *btf, u32 offset)
|
|
{
|
|
if (offset < btf->hdr.str_len)
|
|
return &btf->strings[offset];
|
|
|
|
return NULL;
|
|
}
|
|
|
|
const struct btf_type *btf_type_by_id(const struct btf *btf, u32 type_id)
|
|
{
|
|
if (type_id > btf->nr_types)
|
|
return NULL;
|
|
|
|
return btf->types[type_id];
|
|
}
|
|
|
|
/*
|
|
* Regular int is not a bit field and it must be either
|
|
* u8/u16/u32/u64 or __int128.
|
|
*/
|
|
static bool btf_type_int_is_regular(const struct btf_type *t)
|
|
{
|
|
u8 nr_bits, nr_bytes;
|
|
u32 int_data;
|
|
|
|
int_data = btf_type_int(t);
|
|
nr_bits = BTF_INT_BITS(int_data);
|
|
nr_bytes = BITS_ROUNDUP_BYTES(nr_bits);
|
|
if (BITS_PER_BYTE_MASKED(nr_bits) ||
|
|
BTF_INT_OFFSET(int_data) ||
|
|
(nr_bytes != sizeof(u8) && nr_bytes != sizeof(u16) &&
|
|
nr_bytes != sizeof(u32) && nr_bytes != sizeof(u64) &&
|
|
nr_bytes != (2 * sizeof(u64)))) {
|
|
return false;
|
|
}
|
|
|
|
return true;
|
|
}
|
|
|
|
/*
|
|
* Check that given struct member is a regular int with expected
|
|
* offset and size.
|
|
*/
|
|
bool btf_member_is_reg_int(const struct btf *btf, const struct btf_type *s,
|
|
const struct btf_member *m,
|
|
u32 expected_offset, u32 expected_size)
|
|
{
|
|
const struct btf_type *t;
|
|
u32 id, int_data;
|
|
u8 nr_bits;
|
|
|
|
id = m->type;
|
|
t = btf_type_id_size(btf, &id, NULL);
|
|
if (!t || !btf_type_is_int(t))
|
|
return false;
|
|
|
|
int_data = btf_type_int(t);
|
|
nr_bits = BTF_INT_BITS(int_data);
|
|
if (btf_type_kflag(s)) {
|
|
u32 bitfield_size = BTF_MEMBER_BITFIELD_SIZE(m->offset);
|
|
u32 bit_offset = BTF_MEMBER_BIT_OFFSET(m->offset);
|
|
|
|
/* if kflag set, int should be a regular int and
|
|
* bit offset should be at byte boundary.
|
|
*/
|
|
return !bitfield_size &&
|
|
BITS_ROUNDUP_BYTES(bit_offset) == expected_offset &&
|
|
BITS_ROUNDUP_BYTES(nr_bits) == expected_size;
|
|
}
|
|
|
|
if (BTF_INT_OFFSET(int_data) ||
|
|
BITS_PER_BYTE_MASKED(m->offset) ||
|
|
BITS_ROUNDUP_BYTES(m->offset) != expected_offset ||
|
|
BITS_PER_BYTE_MASKED(nr_bits) ||
|
|
BITS_ROUNDUP_BYTES(nr_bits) != expected_size)
|
|
return false;
|
|
|
|
return true;
|
|
}
|
|
|
|
__printf(2, 3) static void __btf_verifier_log(struct bpf_verifier_log *log,
|
|
const char *fmt, ...)
|
|
{
|
|
va_list args;
|
|
|
|
va_start(args, fmt);
|
|
bpf_verifier_vlog(log, fmt, args);
|
|
va_end(args);
|
|
}
|
|
|
|
__printf(2, 3) static void btf_verifier_log(struct btf_verifier_env *env,
|
|
const char *fmt, ...)
|
|
{
|
|
struct bpf_verifier_log *log = &env->log;
|
|
va_list args;
|
|
|
|
if (!bpf_verifier_log_needed(log))
|
|
return;
|
|
|
|
va_start(args, fmt);
|
|
bpf_verifier_vlog(log, fmt, args);
|
|
va_end(args);
|
|
}
|
|
|
|
__printf(4, 5) static void __btf_verifier_log_type(struct btf_verifier_env *env,
|
|
const struct btf_type *t,
|
|
bool log_details,
|
|
const char *fmt, ...)
|
|
{
|
|
struct bpf_verifier_log *log = &env->log;
|
|
u8 kind = BTF_INFO_KIND(t->info);
|
|
struct btf *btf = env->btf;
|
|
va_list args;
|
|
|
|
if (!bpf_verifier_log_needed(log))
|
|
return;
|
|
|
|
__btf_verifier_log(log, "[%u] %s %s%s",
|
|
env->log_type_id,
|
|
btf_kind_str[kind],
|
|
__btf_name_by_offset(btf, t->name_off),
|
|
log_details ? " " : "");
|
|
|
|
if (log_details)
|
|
btf_type_ops(t)->log_details(env, t);
|
|
|
|
if (fmt && *fmt) {
|
|
__btf_verifier_log(log, " ");
|
|
va_start(args, fmt);
|
|
bpf_verifier_vlog(log, fmt, args);
|
|
va_end(args);
|
|
}
|
|
|
|
__btf_verifier_log(log, "\n");
|
|
}
|
|
|
|
#define btf_verifier_log_type(env, t, ...) \
|
|
__btf_verifier_log_type((env), (t), true, __VA_ARGS__)
|
|
#define btf_verifier_log_basic(env, t, ...) \
|
|
__btf_verifier_log_type((env), (t), false, __VA_ARGS__)
|
|
|
|
__printf(4, 5)
|
|
static void btf_verifier_log_member(struct btf_verifier_env *env,
|
|
const struct btf_type *struct_type,
|
|
const struct btf_member *member,
|
|
const char *fmt, ...)
|
|
{
|
|
struct bpf_verifier_log *log = &env->log;
|
|
struct btf *btf = env->btf;
|
|
va_list args;
|
|
|
|
if (!bpf_verifier_log_needed(log))
|
|
return;
|
|
|
|
/* The CHECK_META phase already did a btf dump.
|
|
*
|
|
* If member is logged again, it must hit an error in
|
|
* parsing this member. It is useful to print out which
|
|
* struct this member belongs to.
|
|
*/
|
|
if (env->phase != CHECK_META)
|
|
btf_verifier_log_type(env, struct_type, NULL);
|
|
|
|
if (btf_type_kflag(struct_type))
|
|
__btf_verifier_log(log,
|
|
"\t%s type_id=%u bitfield_size=%u bits_offset=%u",
|
|
__btf_name_by_offset(btf, member->name_off),
|
|
member->type,
|
|
BTF_MEMBER_BITFIELD_SIZE(member->offset),
|
|
BTF_MEMBER_BIT_OFFSET(member->offset));
|
|
else
|
|
__btf_verifier_log(log, "\t%s type_id=%u bits_offset=%u",
|
|
__btf_name_by_offset(btf, member->name_off),
|
|
member->type, member->offset);
|
|
|
|
if (fmt && *fmt) {
|
|
__btf_verifier_log(log, " ");
|
|
va_start(args, fmt);
|
|
bpf_verifier_vlog(log, fmt, args);
|
|
va_end(args);
|
|
}
|
|
|
|
__btf_verifier_log(log, "\n");
|
|
}
|
|
|
|
__printf(4, 5)
|
|
static void btf_verifier_log_vsi(struct btf_verifier_env *env,
|
|
const struct btf_type *datasec_type,
|
|
const struct btf_var_secinfo *vsi,
|
|
const char *fmt, ...)
|
|
{
|
|
struct bpf_verifier_log *log = &env->log;
|
|
va_list args;
|
|
|
|
if (!bpf_verifier_log_needed(log))
|
|
return;
|
|
if (env->phase != CHECK_META)
|
|
btf_verifier_log_type(env, datasec_type, NULL);
|
|
|
|
__btf_verifier_log(log, "\t type_id=%u offset=%u size=%u",
|
|
vsi->type, vsi->offset, vsi->size);
|
|
if (fmt && *fmt) {
|
|
__btf_verifier_log(log, " ");
|
|
va_start(args, fmt);
|
|
bpf_verifier_vlog(log, fmt, args);
|
|
va_end(args);
|
|
}
|
|
|
|
__btf_verifier_log(log, "\n");
|
|
}
|
|
|
|
static void btf_verifier_log_hdr(struct btf_verifier_env *env,
|
|
u32 btf_data_size)
|
|
{
|
|
struct bpf_verifier_log *log = &env->log;
|
|
const struct btf *btf = env->btf;
|
|
const struct btf_header *hdr;
|
|
|
|
if (!bpf_verifier_log_needed(log))
|
|
return;
|
|
|
|
hdr = &btf->hdr;
|
|
__btf_verifier_log(log, "magic: 0x%x\n", hdr->magic);
|
|
__btf_verifier_log(log, "version: %u\n", hdr->version);
|
|
__btf_verifier_log(log, "flags: 0x%x\n", hdr->flags);
|
|
__btf_verifier_log(log, "hdr_len: %u\n", hdr->hdr_len);
|
|
__btf_verifier_log(log, "type_off: %u\n", hdr->type_off);
|
|
__btf_verifier_log(log, "type_len: %u\n", hdr->type_len);
|
|
__btf_verifier_log(log, "str_off: %u\n", hdr->str_off);
|
|
__btf_verifier_log(log, "str_len: %u\n", hdr->str_len);
|
|
__btf_verifier_log(log, "btf_total_size: %u\n", btf_data_size);
|
|
}
|
|
|
|
static int btf_add_type(struct btf_verifier_env *env, struct btf_type *t)
|
|
{
|
|
struct btf *btf = env->btf;
|
|
|
|
/* < 2 because +1 for btf_void which is always in btf->types[0].
|
|
* btf_void is not accounted in btf->nr_types because btf_void
|
|
* does not come from the BTF file.
|
|
*/
|
|
if (btf->types_size - btf->nr_types < 2) {
|
|
/* Expand 'types' array */
|
|
|
|
struct btf_type **new_types;
|
|
u32 expand_by, new_size;
|
|
|
|
if (btf->types_size == BTF_MAX_TYPE) {
|
|
btf_verifier_log(env, "Exceeded max num of types");
|
|
return -E2BIG;
|
|
}
|
|
|
|
expand_by = max_t(u32, btf->types_size >> 2, 16);
|
|
new_size = min_t(u32, BTF_MAX_TYPE,
|
|
btf->types_size + expand_by);
|
|
|
|
new_types = kvcalloc(new_size, sizeof(*new_types),
|
|
GFP_KERNEL | __GFP_NOWARN);
|
|
if (!new_types)
|
|
return -ENOMEM;
|
|
|
|
if (btf->nr_types == 0)
|
|
new_types[0] = &btf_void;
|
|
else
|
|
memcpy(new_types, btf->types,
|
|
sizeof(*btf->types) * (btf->nr_types + 1));
|
|
|
|
kvfree(btf->types);
|
|
btf->types = new_types;
|
|
btf->types_size = new_size;
|
|
}
|
|
|
|
btf->types[++(btf->nr_types)] = t;
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int btf_alloc_id(struct btf *btf)
|
|
{
|
|
int id;
|
|
|
|
idr_preload(GFP_KERNEL);
|
|
spin_lock_bh(&btf_idr_lock);
|
|
id = idr_alloc_cyclic(&btf_idr, btf, 1, INT_MAX, GFP_ATOMIC);
|
|
if (id > 0)
|
|
btf->id = id;
|
|
spin_unlock_bh(&btf_idr_lock);
|
|
idr_preload_end();
|
|
|
|
if (WARN_ON_ONCE(!id))
|
|
return -ENOSPC;
|
|
|
|
return id > 0 ? 0 : id;
|
|
}
|
|
|
|
static void btf_free_id(struct btf *btf)
|
|
{
|
|
unsigned long flags;
|
|
|
|
/*
|
|
* In map-in-map, calling map_delete_elem() on outer
|
|
* map will call bpf_map_put on the inner map.
|
|
* It will then eventually call btf_free_id()
|
|
* on the inner map. Some of the map_delete_elem()
|
|
* implementation may have irq disabled, so
|
|
* we need to use the _irqsave() version instead
|
|
* of the _bh() version.
|
|
*/
|
|
spin_lock_irqsave(&btf_idr_lock, flags);
|
|
idr_remove(&btf_idr, btf->id);
|
|
spin_unlock_irqrestore(&btf_idr_lock, flags);
|
|
}
|
|
|
|
static void btf_free(struct btf *btf)
|
|
{
|
|
kvfree(btf->types);
|
|
kvfree(btf->resolved_sizes);
|
|
kvfree(btf->resolved_ids);
|
|
kvfree(btf->data);
|
|
kfree(btf);
|
|
}
|
|
|
|
static void btf_free_rcu(struct rcu_head *rcu)
|
|
{
|
|
struct btf *btf = container_of(rcu, struct btf, rcu);
|
|
|
|
btf_free(btf);
|
|
}
|
|
|
|
void btf_put(struct btf *btf)
|
|
{
|
|
if (btf && refcount_dec_and_test(&btf->refcnt)) {
|
|
btf_free_id(btf);
|
|
call_rcu(&btf->rcu, btf_free_rcu);
|
|
}
|
|
}
|
|
|
|
static int env_resolve_init(struct btf_verifier_env *env)
|
|
{
|
|
struct btf *btf = env->btf;
|
|
u32 nr_types = btf->nr_types;
|
|
u32 *resolved_sizes = NULL;
|
|
u32 *resolved_ids = NULL;
|
|
u8 *visit_states = NULL;
|
|
|
|
/* +1 for btf_void */
|
|
resolved_sizes = kvcalloc(nr_types + 1, sizeof(*resolved_sizes),
|
|
GFP_KERNEL | __GFP_NOWARN);
|
|
if (!resolved_sizes)
|
|
goto nomem;
|
|
|
|
resolved_ids = kvcalloc(nr_types + 1, sizeof(*resolved_ids),
|
|
GFP_KERNEL | __GFP_NOWARN);
|
|
if (!resolved_ids)
|
|
goto nomem;
|
|
|
|
visit_states = kvcalloc(nr_types + 1, sizeof(*visit_states),
|
|
GFP_KERNEL | __GFP_NOWARN);
|
|
if (!visit_states)
|
|
goto nomem;
|
|
|
|
btf->resolved_sizes = resolved_sizes;
|
|
btf->resolved_ids = resolved_ids;
|
|
env->visit_states = visit_states;
|
|
|
|
return 0;
|
|
|
|
nomem:
|
|
kvfree(resolved_sizes);
|
|
kvfree(resolved_ids);
|
|
kvfree(visit_states);
|
|
return -ENOMEM;
|
|
}
|
|
|
|
static void btf_verifier_env_free(struct btf_verifier_env *env)
|
|
{
|
|
kvfree(env->visit_states);
|
|
kfree(env);
|
|
}
|
|
|
|
static bool env_type_is_resolve_sink(const struct btf_verifier_env *env,
|
|
const struct btf_type *next_type)
|
|
{
|
|
switch (env->resolve_mode) {
|
|
case RESOLVE_TBD:
|
|
/* int, enum or void is a sink */
|
|
return !btf_type_needs_resolve(next_type);
|
|
case RESOLVE_PTR:
|
|
/* int, enum, void, struct, array, func or func_proto is a sink
|
|
* for ptr
|
|
*/
|
|
return !btf_type_is_modifier(next_type) &&
|
|
!btf_type_is_ptr(next_type);
|
|
case RESOLVE_STRUCT_OR_ARRAY:
|
|
/* int, enum, void, ptr, func or func_proto is a sink
|
|
* for struct and array
|
|
*/
|
|
return !btf_type_is_modifier(next_type) &&
|
|
!btf_type_is_array(next_type) &&
|
|
!btf_type_is_struct(next_type);
|
|
default:
|
|
BUG();
|
|
}
|
|
}
|
|
|
|
static bool env_type_is_resolved(const struct btf_verifier_env *env,
|
|
u32 type_id)
|
|
{
|
|
return env->visit_states[type_id] == RESOLVED;
|
|
}
|
|
|
|
static int env_stack_push(struct btf_verifier_env *env,
|
|
const struct btf_type *t, u32 type_id)
|
|
{
|
|
struct resolve_vertex *v;
|
|
|
|
if (env->top_stack == MAX_RESOLVE_DEPTH)
|
|
return -E2BIG;
|
|
|
|
if (env->visit_states[type_id] != NOT_VISITED)
|
|
return -EEXIST;
|
|
|
|
env->visit_states[type_id] = VISITED;
|
|
|
|
v = &env->stack[env->top_stack++];
|
|
v->t = t;
|
|
v->type_id = type_id;
|
|
v->next_member = 0;
|
|
|
|
if (env->resolve_mode == RESOLVE_TBD) {
|
|
if (btf_type_is_ptr(t))
|
|
env->resolve_mode = RESOLVE_PTR;
|
|
else if (btf_type_is_struct(t) || btf_type_is_array(t))
|
|
env->resolve_mode = RESOLVE_STRUCT_OR_ARRAY;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
static void env_stack_set_next_member(struct btf_verifier_env *env,
|
|
u16 next_member)
|
|
{
|
|
env->stack[env->top_stack - 1].next_member = next_member;
|
|
}
|
|
|
|
static void env_stack_pop_resolved(struct btf_verifier_env *env,
|
|
u32 resolved_type_id,
|
|
u32 resolved_size)
|
|
{
|
|
u32 type_id = env->stack[--(env->top_stack)].type_id;
|
|
struct btf *btf = env->btf;
|
|
|
|
btf->resolved_sizes[type_id] = resolved_size;
|
|
btf->resolved_ids[type_id] = resolved_type_id;
|
|
env->visit_states[type_id] = RESOLVED;
|
|
}
|
|
|
|
static const struct resolve_vertex *env_stack_peak(struct btf_verifier_env *env)
|
|
{
|
|
return env->top_stack ? &env->stack[env->top_stack - 1] : NULL;
|
|
}
|
|
|
|
/* The input param "type_id" must point to a needs_resolve type */
|
|
static const struct btf_type *btf_type_id_resolve(const struct btf *btf,
|
|
u32 *type_id)
|
|
{
|
|
*type_id = btf->resolved_ids[*type_id];
|
|
return btf_type_by_id(btf, *type_id);
|
|
}
|
|
|
|
const struct btf_type *btf_type_id_size(const struct btf *btf,
|
|
u32 *type_id, u32 *ret_size)
|
|
{
|
|
const struct btf_type *size_type;
|
|
u32 size_type_id = *type_id;
|
|
u32 size = 0;
|
|
|
|
size_type = btf_type_by_id(btf, size_type_id);
|
|
if (btf_type_nosize_or_null(size_type))
|
|
return NULL;
|
|
|
|
if (btf_type_has_size(size_type)) {
|
|
size = size_type->size;
|
|
} else if (btf_type_is_array(size_type)) {
|
|
size = btf->resolved_sizes[size_type_id];
|
|
} else if (btf_type_is_ptr(size_type)) {
|
|
size = sizeof(void *);
|
|
} else {
|
|
if (WARN_ON_ONCE(!btf_type_is_modifier(size_type) &&
|
|
!btf_type_is_var(size_type)))
|
|
return NULL;
|
|
|
|
size_type_id = btf->resolved_ids[size_type_id];
|
|
size_type = btf_type_by_id(btf, size_type_id);
|
|
if (btf_type_nosize_or_null(size_type))
|
|
return NULL;
|
|
else if (btf_type_has_size(size_type))
|
|
size = size_type->size;
|
|
else if (btf_type_is_array(size_type))
|
|
size = btf->resolved_sizes[size_type_id];
|
|
else if (btf_type_is_ptr(size_type))
|
|
size = sizeof(void *);
|
|
else
|
|
return NULL;
|
|
}
|
|
|
|
*type_id = size_type_id;
|
|
if (ret_size)
|
|
*ret_size = size;
|
|
|
|
return size_type;
|
|
}
|
|
|
|
static int btf_df_check_member(struct btf_verifier_env *env,
|
|
const struct btf_type *struct_type,
|
|
const struct btf_member *member,
|
|
const struct btf_type *member_type)
|
|
{
|
|
btf_verifier_log_basic(env, struct_type,
|
|
"Unsupported check_member");
|
|
return -EINVAL;
|
|
}
|
|
|
|
static int btf_df_check_kflag_member(struct btf_verifier_env *env,
|
|
const struct btf_type *struct_type,
|
|
const struct btf_member *member,
|
|
const struct btf_type *member_type)
|
|
{
|
|
btf_verifier_log_basic(env, struct_type,
|
|
"Unsupported check_kflag_member");
|
|
return -EINVAL;
|
|
}
|
|
|
|
/* Used for ptr, array and struct/union type members.
|
|
* int, enum and modifier types have their specific callback functions.
|
|
*/
|
|
static int btf_generic_check_kflag_member(struct btf_verifier_env *env,
|
|
const struct btf_type *struct_type,
|
|
const struct btf_member *member,
|
|
const struct btf_type *member_type)
|
|
{
|
|
if (BTF_MEMBER_BITFIELD_SIZE(member->offset)) {
|
|
btf_verifier_log_member(env, struct_type, member,
|
|
"Invalid member bitfield_size");
|
|
return -EINVAL;
|
|
}
|
|
|
|
/* bitfield size is 0, so member->offset represents bit offset only.
|
|
* It is safe to call non kflag check_member variants.
|
|
*/
|
|
return btf_type_ops(member_type)->check_member(env, struct_type,
|
|
member,
|
|
member_type);
|
|
}
|
|
|
|
static int btf_df_resolve(struct btf_verifier_env *env,
|
|
const struct resolve_vertex *v)
|
|
{
|
|
btf_verifier_log_basic(env, v->t, "Unsupported resolve");
|
|
return -EINVAL;
|
|
}
|
|
|
|
static void btf_df_seq_show(const struct btf *btf, const struct btf_type *t,
|
|
u32 type_id, void *data, u8 bits_offsets,
|
|
struct seq_file *m)
|
|
{
|
|
seq_printf(m, "<unsupported kind:%u>", BTF_INFO_KIND(t->info));
|
|
}
|
|
|
|
static int btf_int_check_member(struct btf_verifier_env *env,
|
|
const struct btf_type *struct_type,
|
|
const struct btf_member *member,
|
|
const struct btf_type *member_type)
|
|
{
|
|
u32 int_data = btf_type_int(member_type);
|
|
u32 struct_bits_off = member->offset;
|
|
u32 struct_size = struct_type->size;
|
|
u32 nr_copy_bits;
|
|
u32 bytes_offset;
|
|
|
|
if (U32_MAX - struct_bits_off < BTF_INT_OFFSET(int_data)) {
|
|
btf_verifier_log_member(env, struct_type, member,
|
|
"bits_offset exceeds U32_MAX");
|
|
return -EINVAL;
|
|
}
|
|
|
|
struct_bits_off += BTF_INT_OFFSET(int_data);
|
|
bytes_offset = BITS_ROUNDDOWN_BYTES(struct_bits_off);
|
|
nr_copy_bits = BTF_INT_BITS(int_data) +
|
|
BITS_PER_BYTE_MASKED(struct_bits_off);
|
|
|
|
if (nr_copy_bits > BITS_PER_U128) {
|
|
btf_verifier_log_member(env, struct_type, member,
|
|
"nr_copy_bits exceeds 128");
|
|
return -EINVAL;
|
|
}
|
|
|
|
if (struct_size < bytes_offset ||
|
|
struct_size - bytes_offset < BITS_ROUNDUP_BYTES(nr_copy_bits)) {
|
|
btf_verifier_log_member(env, struct_type, member,
|
|
"Member exceeds struct_size");
|
|
return -EINVAL;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int btf_int_check_kflag_member(struct btf_verifier_env *env,
|
|
const struct btf_type *struct_type,
|
|
const struct btf_member *member,
|
|
const struct btf_type *member_type)
|
|
{
|
|
u32 struct_bits_off, nr_bits, nr_int_data_bits, bytes_offset;
|
|
u32 int_data = btf_type_int(member_type);
|
|
u32 struct_size = struct_type->size;
|
|
u32 nr_copy_bits;
|
|
|
|
/* a regular int type is required for the kflag int member */
|
|
if (!btf_type_int_is_regular(member_type)) {
|
|
btf_verifier_log_member(env, struct_type, member,
|
|
"Invalid member base type");
|
|
return -EINVAL;
|
|
}
|
|
|
|
/* check sanity of bitfield size */
|
|
nr_bits = BTF_MEMBER_BITFIELD_SIZE(member->offset);
|
|
struct_bits_off = BTF_MEMBER_BIT_OFFSET(member->offset);
|
|
nr_int_data_bits = BTF_INT_BITS(int_data);
|
|
if (!nr_bits) {
|
|
/* Not a bitfield member, member offset must be at byte
|
|
* boundary.
|
|
*/
|
|
if (BITS_PER_BYTE_MASKED(struct_bits_off)) {
|
|
btf_verifier_log_member(env, struct_type, member,
|
|
"Invalid member offset");
|
|
return -EINVAL;
|
|
}
|
|
|
|
nr_bits = nr_int_data_bits;
|
|
} else if (nr_bits > nr_int_data_bits) {
|
|
btf_verifier_log_member(env, struct_type, member,
|
|
"Invalid member bitfield_size");
|
|
return -EINVAL;
|
|
}
|
|
|
|
bytes_offset = BITS_ROUNDDOWN_BYTES(struct_bits_off);
|
|
nr_copy_bits = nr_bits + BITS_PER_BYTE_MASKED(struct_bits_off);
|
|
if (nr_copy_bits > BITS_PER_U128) {
|
|
btf_verifier_log_member(env, struct_type, member,
|
|
"nr_copy_bits exceeds 128");
|
|
return -EINVAL;
|
|
}
|
|
|
|
if (struct_size < bytes_offset ||
|
|
struct_size - bytes_offset < BITS_ROUNDUP_BYTES(nr_copy_bits)) {
|
|
btf_verifier_log_member(env, struct_type, member,
|
|
"Member exceeds struct_size");
|
|
return -EINVAL;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
static s32 btf_int_check_meta(struct btf_verifier_env *env,
|
|
const struct btf_type *t,
|
|
u32 meta_left)
|
|
{
|
|
u32 int_data, nr_bits, meta_needed = sizeof(int_data);
|
|
u16 encoding;
|
|
|
|
if (meta_left < meta_needed) {
|
|
btf_verifier_log_basic(env, t,
|
|
"meta_left:%u meta_needed:%u",
|
|
meta_left, meta_needed);
|
|
return -EINVAL;
|
|
}
|
|
|
|
if (btf_type_vlen(t)) {
|
|
btf_verifier_log_type(env, t, "vlen != 0");
|
|
return -EINVAL;
|
|
}
|
|
|
|
if (btf_type_kflag(t)) {
|
|
btf_verifier_log_type(env, t, "Invalid btf_info kind_flag");
|
|
return -EINVAL;
|
|
}
|
|
|
|
int_data = btf_type_int(t);
|
|
if (int_data & ~BTF_INT_MASK) {
|
|
btf_verifier_log_basic(env, t, "Invalid int_data:%x",
|
|
int_data);
|
|
return -EINVAL;
|
|
}
|
|
|
|
nr_bits = BTF_INT_BITS(int_data) + BTF_INT_OFFSET(int_data);
|
|
|
|
if (nr_bits > BITS_PER_U128) {
|
|
btf_verifier_log_type(env, t, "nr_bits exceeds %zu",
|
|
BITS_PER_U128);
|
|
return -EINVAL;
|
|
}
|
|
|
|
if (BITS_ROUNDUP_BYTES(nr_bits) > t->size) {
|
|
btf_verifier_log_type(env, t, "nr_bits exceeds type_size");
|
|
return -EINVAL;
|
|
}
|
|
|
|
/*
|
|
* Only one of the encoding bits is allowed and it
|
|
* should be sufficient for the pretty print purpose (i.e. decoding).
|
|
* Multiple bits can be allowed later if it is found
|
|
* to be insufficient.
|
|
*/
|
|
encoding = BTF_INT_ENCODING(int_data);
|
|
if (encoding &&
|
|
encoding != BTF_INT_SIGNED &&
|
|
encoding != BTF_INT_CHAR &&
|
|
encoding != BTF_INT_BOOL) {
|
|
btf_verifier_log_type(env, t, "Unsupported encoding");
|
|
return -ENOTSUPP;
|
|
}
|
|
|
|
btf_verifier_log_type(env, t, NULL);
|
|
|
|
return meta_needed;
|
|
}
|
|
|
|
static void btf_int_log(struct btf_verifier_env *env,
|
|
const struct btf_type *t)
|
|
{
|
|
int int_data = btf_type_int(t);
|
|
|
|
btf_verifier_log(env,
|
|
"size=%u bits_offset=%u nr_bits=%u encoding=%s",
|
|
t->size, BTF_INT_OFFSET(int_data),
|
|
BTF_INT_BITS(int_data),
|
|
btf_int_encoding_str(BTF_INT_ENCODING(int_data)));
|
|
}
|
|
|
|
static void btf_int128_print(struct seq_file *m, void *data)
|
|
{
|
|
/* data points to a __int128 number.
|
|
* Suppose
|
|
* int128_num = *(__int128 *)data;
|
|
* The below formulas shows what upper_num and lower_num represents:
|
|
* upper_num = int128_num >> 64;
|
|
* lower_num = int128_num & 0xffffffffFFFFFFFFULL;
|
|
*/
|
|
u64 upper_num, lower_num;
|
|
|
|
#ifdef __BIG_ENDIAN_BITFIELD
|
|
upper_num = *(u64 *)data;
|
|
lower_num = *(u64 *)(data + 8);
|
|
#else
|
|
upper_num = *(u64 *)(data + 8);
|
|
lower_num = *(u64 *)data;
|
|
#endif
|
|
if (upper_num == 0)
|
|
seq_printf(m, "0x%llx", lower_num);
|
|
else
|
|
seq_printf(m, "0x%llx%016llx", upper_num, lower_num);
|
|
}
|
|
|
|
static void btf_int128_shift(u64 *print_num, u16 left_shift_bits,
|
|
u16 right_shift_bits)
|
|
{
|
|
u64 upper_num, lower_num;
|
|
|
|
#ifdef __BIG_ENDIAN_BITFIELD
|
|
upper_num = print_num[0];
|
|
lower_num = print_num[1];
|
|
#else
|
|
upper_num = print_num[1];
|
|
lower_num = print_num[0];
|
|
#endif
|
|
|
|
/* shake out un-needed bits by shift/or operations */
|
|
if (left_shift_bits >= 64) {
|
|
upper_num = lower_num << (left_shift_bits - 64);
|
|
lower_num = 0;
|
|
} else {
|
|
upper_num = (upper_num << left_shift_bits) |
|
|
(lower_num >> (64 - left_shift_bits));
|
|
lower_num = lower_num << left_shift_bits;
|
|
}
|
|
|
|
if (right_shift_bits >= 64) {
|
|
lower_num = upper_num >> (right_shift_bits - 64);
|
|
upper_num = 0;
|
|
} else {
|
|
lower_num = (lower_num >> right_shift_bits) |
|
|
(upper_num << (64 - right_shift_bits));
|
|
upper_num = upper_num >> right_shift_bits;
|
|
}
|
|
|
|
#ifdef __BIG_ENDIAN_BITFIELD
|
|
print_num[0] = upper_num;
|
|
print_num[1] = lower_num;
|
|
#else
|
|
print_num[0] = lower_num;
|
|
print_num[1] = upper_num;
|
|
#endif
|
|
}
|
|
|
|
static void btf_bitfield_seq_show(void *data, u8 bits_offset,
|
|
u8 nr_bits, struct seq_file *m)
|
|
{
|
|
u16 left_shift_bits, right_shift_bits;
|
|
u8 nr_copy_bytes;
|
|
u8 nr_copy_bits;
|
|
u64 print_num[2] = {};
|
|
|
|
nr_copy_bits = nr_bits + bits_offset;
|
|
nr_copy_bytes = BITS_ROUNDUP_BYTES(nr_copy_bits);
|
|
|
|
memcpy(print_num, data, nr_copy_bytes);
|
|
|
|
#ifdef __BIG_ENDIAN_BITFIELD
|
|
left_shift_bits = bits_offset;
|
|
#else
|
|
left_shift_bits = BITS_PER_U128 - nr_copy_bits;
|
|
#endif
|
|
right_shift_bits = BITS_PER_U128 - nr_bits;
|
|
|
|
btf_int128_shift(print_num, left_shift_bits, right_shift_bits);
|
|
btf_int128_print(m, print_num);
|
|
}
|
|
|
|
|
|
static void btf_int_bits_seq_show(const struct btf *btf,
|
|
const struct btf_type *t,
|
|
void *data, u8 bits_offset,
|
|
struct seq_file *m)
|
|
{
|
|
u32 int_data = btf_type_int(t);
|
|
u8 nr_bits = BTF_INT_BITS(int_data);
|
|
u8 total_bits_offset;
|
|
|
|
/*
|
|
* bits_offset is at most 7.
|
|
* BTF_INT_OFFSET() cannot exceed 128 bits.
|
|
*/
|
|
total_bits_offset = bits_offset + BTF_INT_OFFSET(int_data);
|
|
data += BITS_ROUNDDOWN_BYTES(total_bits_offset);
|
|
bits_offset = BITS_PER_BYTE_MASKED(total_bits_offset);
|
|
btf_bitfield_seq_show(data, bits_offset, nr_bits, m);
|
|
}
|
|
|
|
static void btf_int_seq_show(const struct btf *btf, const struct btf_type *t,
|
|
u32 type_id, void *data, u8 bits_offset,
|
|
struct seq_file *m)
|
|
{
|
|
u32 int_data = btf_type_int(t);
|
|
u8 encoding = BTF_INT_ENCODING(int_data);
|
|
bool sign = encoding & BTF_INT_SIGNED;
|
|
u8 nr_bits = BTF_INT_BITS(int_data);
|
|
|
|
if (bits_offset || BTF_INT_OFFSET(int_data) ||
|
|
BITS_PER_BYTE_MASKED(nr_bits)) {
|
|
btf_int_bits_seq_show(btf, t, data, bits_offset, m);
|
|
return;
|
|
}
|
|
|
|
switch (nr_bits) {
|
|
case 128:
|
|
btf_int128_print(m, data);
|
|
break;
|
|
case 64:
|
|
if (sign)
|
|
seq_printf(m, "%lld", *(s64 *)data);
|
|
else
|
|
seq_printf(m, "%llu", *(u64 *)data);
|
|
break;
|
|
case 32:
|
|
if (sign)
|
|
seq_printf(m, "%d", *(s32 *)data);
|
|
else
|
|
seq_printf(m, "%u", *(u32 *)data);
|
|
break;
|
|
case 16:
|
|
if (sign)
|
|
seq_printf(m, "%d", *(s16 *)data);
|
|
else
|
|
seq_printf(m, "%u", *(u16 *)data);
|
|
break;
|
|
case 8:
|
|
if (sign)
|
|
seq_printf(m, "%d", *(s8 *)data);
|
|
else
|
|
seq_printf(m, "%u", *(u8 *)data);
|
|
break;
|
|
default:
|
|
btf_int_bits_seq_show(btf, t, data, bits_offset, m);
|
|
}
|
|
}
|
|
|
|
static const struct btf_kind_operations int_ops = {
|
|
.check_meta = btf_int_check_meta,
|
|
.resolve = btf_df_resolve,
|
|
.check_member = btf_int_check_member,
|
|
.check_kflag_member = btf_int_check_kflag_member,
|
|
.log_details = btf_int_log,
|
|
.seq_show = btf_int_seq_show,
|
|
};
|
|
|
|
static int btf_modifier_check_member(struct btf_verifier_env *env,
|
|
const struct btf_type *struct_type,
|
|
const struct btf_member *member,
|
|
const struct btf_type *member_type)
|
|
{
|
|
const struct btf_type *resolved_type;
|
|
u32 resolved_type_id = member->type;
|
|
struct btf_member resolved_member;
|
|
struct btf *btf = env->btf;
|
|
|
|
resolved_type = btf_type_id_size(btf, &resolved_type_id, NULL);
|
|
if (!resolved_type) {
|
|
btf_verifier_log_member(env, struct_type, member,
|
|
"Invalid member");
|
|
return -EINVAL;
|
|
}
|
|
|
|
resolved_member = *member;
|
|
resolved_member.type = resolved_type_id;
|
|
|
|
return btf_type_ops(resolved_type)->check_member(env, struct_type,
|
|
&resolved_member,
|
|
resolved_type);
|
|
}
|
|
|
|
static int btf_modifier_check_kflag_member(struct btf_verifier_env *env,
|
|
const struct btf_type *struct_type,
|
|
const struct btf_member *member,
|
|
const struct btf_type *member_type)
|
|
{
|
|
const struct btf_type *resolved_type;
|
|
u32 resolved_type_id = member->type;
|
|
struct btf_member resolved_member;
|
|
struct btf *btf = env->btf;
|
|
|
|
resolved_type = btf_type_id_size(btf, &resolved_type_id, NULL);
|
|
if (!resolved_type) {
|
|
btf_verifier_log_member(env, struct_type, member,
|
|
"Invalid member");
|
|
return -EINVAL;
|
|
}
|
|
|
|
resolved_member = *member;
|
|
resolved_member.type = resolved_type_id;
|
|
|
|
return btf_type_ops(resolved_type)->check_kflag_member(env, struct_type,
|
|
&resolved_member,
|
|
resolved_type);
|
|
}
|
|
|
|
static int btf_ptr_check_member(struct btf_verifier_env *env,
|
|
const struct btf_type *struct_type,
|
|
const struct btf_member *member,
|
|
const struct btf_type *member_type)
|
|
{
|
|
u32 struct_size, struct_bits_off, bytes_offset;
|
|
|
|
struct_size = struct_type->size;
|
|
struct_bits_off = member->offset;
|
|
bytes_offset = BITS_ROUNDDOWN_BYTES(struct_bits_off);
|
|
|
|
if (BITS_PER_BYTE_MASKED(struct_bits_off)) {
|
|
btf_verifier_log_member(env, struct_type, member,
|
|
"Member is not byte aligned");
|
|
return -EINVAL;
|
|
}
|
|
|
|
if (struct_size - bytes_offset < sizeof(void *)) {
|
|
btf_verifier_log_member(env, struct_type, member,
|
|
"Member exceeds struct_size");
|
|
return -EINVAL;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int btf_ref_type_check_meta(struct btf_verifier_env *env,
|
|
const struct btf_type *t,
|
|
u32 meta_left)
|
|
{
|
|
if (btf_type_vlen(t)) {
|
|
btf_verifier_log_type(env, t, "vlen != 0");
|
|
return -EINVAL;
|
|
}
|
|
|
|
if (btf_type_kflag(t)) {
|
|
btf_verifier_log_type(env, t, "Invalid btf_info kind_flag");
|
|
return -EINVAL;
|
|
}
|
|
|
|
if (!BTF_TYPE_ID_VALID(t->type)) {
|
|
btf_verifier_log_type(env, t, "Invalid type_id");
|
|
return -EINVAL;
|
|
}
|
|
|
|
/* typedef type must have a valid name, and other ref types,
|
|
* volatile, const, restrict, should have a null name.
|
|
*/
|
|
if (BTF_INFO_KIND(t->info) == BTF_KIND_TYPEDEF) {
|
|
if (!t->name_off ||
|
|
!btf_name_valid_identifier(env->btf, t->name_off)) {
|
|
btf_verifier_log_type(env, t, "Invalid name");
|
|
return -EINVAL;
|
|
}
|
|
} else {
|
|
if (t->name_off) {
|
|
btf_verifier_log_type(env, t, "Invalid name");
|
|
return -EINVAL;
|
|
}
|
|
}
|
|
|
|
btf_verifier_log_type(env, t, NULL);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int btf_modifier_resolve(struct btf_verifier_env *env,
|
|
const struct resolve_vertex *v)
|
|
{
|
|
const struct btf_type *t = v->t;
|
|
const struct btf_type *next_type;
|
|
u32 next_type_id = t->type;
|
|
struct btf *btf = env->btf;
|
|
|
|
next_type = btf_type_by_id(btf, next_type_id);
|
|
if (!next_type || btf_type_is_resolve_source_only(next_type)) {
|
|
btf_verifier_log_type(env, v->t, "Invalid type_id");
|
|
return -EINVAL;
|
|
}
|
|
|
|
if (!env_type_is_resolve_sink(env, next_type) &&
|
|
!env_type_is_resolved(env, next_type_id))
|
|
return env_stack_push(env, next_type, next_type_id);
|
|
|
|
/* Figure out the resolved next_type_id with size.
|
|
* They will be stored in the current modifier's
|
|
* resolved_ids and resolved_sizes such that it can
|
|
* save us a few type-following when we use it later (e.g. in
|
|
* pretty print).
|
|
*/
|
|
if (!btf_type_id_size(btf, &next_type_id, NULL)) {
|
|
if (env_type_is_resolved(env, next_type_id))
|
|
next_type = btf_type_id_resolve(btf, &next_type_id);
|
|
|
|
/* "typedef void new_void", "const void"...etc */
|
|
if (!btf_type_is_void(next_type) &&
|
|
!btf_type_is_fwd(next_type) &&
|
|
!btf_type_is_func_proto(next_type)) {
|
|
btf_verifier_log_type(env, v->t, "Invalid type_id");
|
|
return -EINVAL;
|
|
}
|
|
}
|
|
|
|
env_stack_pop_resolved(env, next_type_id, 0);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int btf_var_resolve(struct btf_verifier_env *env,
|
|
const struct resolve_vertex *v)
|
|
{
|
|
const struct btf_type *next_type;
|
|
const struct btf_type *t = v->t;
|
|
u32 next_type_id = t->type;
|
|
struct btf *btf = env->btf;
|
|
|
|
next_type = btf_type_by_id(btf, next_type_id);
|
|
if (!next_type || btf_type_is_resolve_source_only(next_type)) {
|
|
btf_verifier_log_type(env, v->t, "Invalid type_id");
|
|
return -EINVAL;
|
|
}
|
|
|
|
if (!env_type_is_resolve_sink(env, next_type) &&
|
|
!env_type_is_resolved(env, next_type_id))
|
|
return env_stack_push(env, next_type, next_type_id);
|
|
|
|
if (btf_type_is_modifier(next_type)) {
|
|
const struct btf_type *resolved_type;
|
|
u32 resolved_type_id;
|
|
|
|
resolved_type_id = next_type_id;
|
|
resolved_type = btf_type_id_resolve(btf, &resolved_type_id);
|
|
|
|
if (btf_type_is_ptr(resolved_type) &&
|
|
!env_type_is_resolve_sink(env, resolved_type) &&
|
|
!env_type_is_resolved(env, resolved_type_id))
|
|
return env_stack_push(env, resolved_type,
|
|
resolved_type_id);
|
|
}
|
|
|
|
/* We must resolve to something concrete at this point, no
|
|
* forward types or similar that would resolve to size of
|
|
* zero is allowed.
|
|
*/
|
|
if (!btf_type_id_size(btf, &next_type_id, NULL)) {
|
|
btf_verifier_log_type(env, v->t, "Invalid type_id");
|
|
return -EINVAL;
|
|
}
|
|
|
|
env_stack_pop_resolved(env, next_type_id, 0);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int btf_ptr_resolve(struct btf_verifier_env *env,
|
|
const struct resolve_vertex *v)
|
|
{
|
|
const struct btf_type *next_type;
|
|
const struct btf_type *t = v->t;
|
|
u32 next_type_id = t->type;
|
|
struct btf *btf = env->btf;
|
|
|
|
next_type = btf_type_by_id(btf, next_type_id);
|
|
if (!next_type || btf_type_is_resolve_source_only(next_type)) {
|
|
btf_verifier_log_type(env, v->t, "Invalid type_id");
|
|
return -EINVAL;
|
|
}
|
|
|
|
if (!env_type_is_resolve_sink(env, next_type) &&
|
|
!env_type_is_resolved(env, next_type_id))
|
|
return env_stack_push(env, next_type, next_type_id);
|
|
|
|
/* If the modifier was RESOLVED during RESOLVE_STRUCT_OR_ARRAY,
|
|
* the modifier may have stopped resolving when it was resolved
|
|
* to a ptr (last-resolved-ptr).
|
|
*
|
|
* We now need to continue from the last-resolved-ptr to
|
|
* ensure the last-resolved-ptr will not referring back to
|
|
* the currenct ptr (t).
|
|
*/
|
|
if (btf_type_is_modifier(next_type)) {
|
|
const struct btf_type *resolved_type;
|
|
u32 resolved_type_id;
|
|
|
|
resolved_type_id = next_type_id;
|
|
resolved_type = btf_type_id_resolve(btf, &resolved_type_id);
|
|
|
|
if (btf_type_is_ptr(resolved_type) &&
|
|
!env_type_is_resolve_sink(env, resolved_type) &&
|
|
!env_type_is_resolved(env, resolved_type_id))
|
|
return env_stack_push(env, resolved_type,
|
|
resolved_type_id);
|
|
}
|
|
|
|
if (!btf_type_id_size(btf, &next_type_id, NULL)) {
|
|
if (env_type_is_resolved(env, next_type_id))
|
|
next_type = btf_type_id_resolve(btf, &next_type_id);
|
|
|
|
if (!btf_type_is_void(next_type) &&
|
|
!btf_type_is_fwd(next_type) &&
|
|
!btf_type_is_func_proto(next_type)) {
|
|
btf_verifier_log_type(env, v->t, "Invalid type_id");
|
|
return -EINVAL;
|
|
}
|
|
}
|
|
|
|
env_stack_pop_resolved(env, next_type_id, 0);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static void btf_modifier_seq_show(const struct btf *btf,
|
|
const struct btf_type *t,
|
|
u32 type_id, void *data,
|
|
u8 bits_offset, struct seq_file *m)
|
|
{
|
|
t = btf_type_id_resolve(btf, &type_id);
|
|
|
|
btf_type_ops(t)->seq_show(btf, t, type_id, data, bits_offset, m);
|
|
}
|
|
|
|
static void btf_var_seq_show(const struct btf *btf, const struct btf_type *t,
|
|
u32 type_id, void *data, u8 bits_offset,
|
|
struct seq_file *m)
|
|
{
|
|
t = btf_type_id_resolve(btf, &type_id);
|
|
|
|
btf_type_ops(t)->seq_show(btf, t, type_id, data, bits_offset, m);
|
|
}
|
|
|
|
static void btf_ptr_seq_show(const struct btf *btf, const struct btf_type *t,
|
|
u32 type_id, void *data, u8 bits_offset,
|
|
struct seq_file *m)
|
|
{
|
|
/* It is a hashed value */
|
|
seq_printf(m, "%p", *(void **)data);
|
|
}
|
|
|
|
static void btf_ref_type_log(struct btf_verifier_env *env,
|
|
const struct btf_type *t)
|
|
{
|
|
btf_verifier_log(env, "type_id=%u", t->type);
|
|
}
|
|
|
|
static struct btf_kind_operations modifier_ops = {
|
|
.check_meta = btf_ref_type_check_meta,
|
|
.resolve = btf_modifier_resolve,
|
|
.check_member = btf_modifier_check_member,
|
|
.check_kflag_member = btf_modifier_check_kflag_member,
|
|
.log_details = btf_ref_type_log,
|
|
.seq_show = btf_modifier_seq_show,
|
|
};
|
|
|
|
static struct btf_kind_operations ptr_ops = {
|
|
.check_meta = btf_ref_type_check_meta,
|
|
.resolve = btf_ptr_resolve,
|
|
.check_member = btf_ptr_check_member,
|
|
.check_kflag_member = btf_generic_check_kflag_member,
|
|
.log_details = btf_ref_type_log,
|
|
.seq_show = btf_ptr_seq_show,
|
|
};
|
|
|
|
static s32 btf_fwd_check_meta(struct btf_verifier_env *env,
|
|
const struct btf_type *t,
|
|
u32 meta_left)
|
|
{
|
|
if (btf_type_vlen(t)) {
|
|
btf_verifier_log_type(env, t, "vlen != 0");
|
|
return -EINVAL;
|
|
}
|
|
|
|
if (t->type) {
|
|
btf_verifier_log_type(env, t, "type != 0");
|
|
return -EINVAL;
|
|
}
|
|
|
|
/* fwd type must have a valid name */
|
|
if (!t->name_off ||
|
|
!btf_name_valid_identifier(env->btf, t->name_off)) {
|
|
btf_verifier_log_type(env, t, "Invalid name");
|
|
return -EINVAL;
|
|
}
|
|
|
|
btf_verifier_log_type(env, t, NULL);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static void btf_fwd_type_log(struct btf_verifier_env *env,
|
|
const struct btf_type *t)
|
|
{
|
|
btf_verifier_log(env, "%s", btf_type_kflag(t) ? "union" : "struct");
|
|
}
|
|
|
|
static struct btf_kind_operations fwd_ops = {
|
|
.check_meta = btf_fwd_check_meta,
|
|
.resolve = btf_df_resolve,
|
|
.check_member = btf_df_check_member,
|
|
.check_kflag_member = btf_df_check_kflag_member,
|
|
.log_details = btf_fwd_type_log,
|
|
.seq_show = btf_df_seq_show,
|
|
};
|
|
|
|
static int btf_array_check_member(struct btf_verifier_env *env,
|
|
const struct btf_type *struct_type,
|
|
const struct btf_member *member,
|
|
const struct btf_type *member_type)
|
|
{
|
|
u32 struct_bits_off = member->offset;
|
|
u32 struct_size, bytes_offset;
|
|
u32 array_type_id, array_size;
|
|
struct btf *btf = env->btf;
|
|
|
|
if (BITS_PER_BYTE_MASKED(struct_bits_off)) {
|
|
btf_verifier_log_member(env, struct_type, member,
|
|
"Member is not byte aligned");
|
|
return -EINVAL;
|
|
}
|
|
|
|
array_type_id = member->type;
|
|
btf_type_id_size(btf, &array_type_id, &array_size);
|
|
struct_size = struct_type->size;
|
|
bytes_offset = BITS_ROUNDDOWN_BYTES(struct_bits_off);
|
|
if (struct_size - bytes_offset < array_size) {
|
|
btf_verifier_log_member(env, struct_type, member,
|
|
"Member exceeds struct_size");
|
|
return -EINVAL;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
static s32 btf_array_check_meta(struct btf_verifier_env *env,
|
|
const struct btf_type *t,
|
|
u32 meta_left)
|
|
{
|
|
const struct btf_array *array = btf_type_array(t);
|
|
u32 meta_needed = sizeof(*array);
|
|
|
|
if (meta_left < meta_needed) {
|
|
btf_verifier_log_basic(env, t,
|
|
"meta_left:%u meta_needed:%u",
|
|
meta_left, meta_needed);
|
|
return -EINVAL;
|
|
}
|
|
|
|
/* array type should not have a name */
|
|
if (t->name_off) {
|
|
btf_verifier_log_type(env, t, "Invalid name");
|
|
return -EINVAL;
|
|
}
|
|
|
|
if (btf_type_vlen(t)) {
|
|
btf_verifier_log_type(env, t, "vlen != 0");
|
|
return -EINVAL;
|
|
}
|
|
|
|
if (btf_type_kflag(t)) {
|
|
btf_verifier_log_type(env, t, "Invalid btf_info kind_flag");
|
|
return -EINVAL;
|
|
}
|
|
|
|
if (t->size) {
|
|
btf_verifier_log_type(env, t, "size != 0");
|
|
return -EINVAL;
|
|
}
|
|
|
|
/* Array elem type and index type cannot be in type void,
|
|
* so !array->type and !array->index_type are not allowed.
|
|
*/
|
|
if (!array->type || !BTF_TYPE_ID_VALID(array->type)) {
|
|
btf_verifier_log_type(env, t, "Invalid elem");
|
|
return -EINVAL;
|
|
}
|
|
|
|
if (!array->index_type || !BTF_TYPE_ID_VALID(array->index_type)) {
|
|
btf_verifier_log_type(env, t, "Invalid index");
|
|
return -EINVAL;
|
|
}
|
|
|
|
btf_verifier_log_type(env, t, NULL);
|
|
|
|
return meta_needed;
|
|
}
|
|
|
|
static int btf_array_resolve(struct btf_verifier_env *env,
|
|
const struct resolve_vertex *v)
|
|
{
|
|
const struct btf_array *array = btf_type_array(v->t);
|
|
const struct btf_type *elem_type, *index_type;
|
|
u32 elem_type_id, index_type_id;
|
|
struct btf *btf = env->btf;
|
|
u32 elem_size;
|
|
|
|
/* Check array->index_type */
|
|
index_type_id = array->index_type;
|
|
index_type = btf_type_by_id(btf, index_type_id);
|
|
if (btf_type_nosize_or_null(index_type) ||
|
|
btf_type_is_resolve_source_only(index_type)) {
|
|
btf_verifier_log_type(env, v->t, "Invalid index");
|
|
return -EINVAL;
|
|
}
|
|
|
|
if (!env_type_is_resolve_sink(env, index_type) &&
|
|
!env_type_is_resolved(env, index_type_id))
|
|
return env_stack_push(env, index_type, index_type_id);
|
|
|
|
index_type = btf_type_id_size(btf, &index_type_id, NULL);
|
|
if (!index_type || !btf_type_is_int(index_type) ||
|
|
!btf_type_int_is_regular(index_type)) {
|
|
btf_verifier_log_type(env, v->t, "Invalid index");
|
|
return -EINVAL;
|
|
}
|
|
|
|
/* Check array->type */
|
|
elem_type_id = array->type;
|
|
elem_type = btf_type_by_id(btf, elem_type_id);
|
|
if (btf_type_nosize_or_null(elem_type) ||
|
|
btf_type_is_resolve_source_only(elem_type)) {
|
|
btf_verifier_log_type(env, v->t,
|
|
"Invalid elem");
|
|
return -EINVAL;
|
|
}
|
|
|
|
if (!env_type_is_resolve_sink(env, elem_type) &&
|
|
!env_type_is_resolved(env, elem_type_id))
|
|
return env_stack_push(env, elem_type, elem_type_id);
|
|
|
|
elem_type = btf_type_id_size(btf, &elem_type_id, &elem_size);
|
|
if (!elem_type) {
|
|
btf_verifier_log_type(env, v->t, "Invalid elem");
|
|
return -EINVAL;
|
|
}
|
|
|
|
if (btf_type_is_int(elem_type) && !btf_type_int_is_regular(elem_type)) {
|
|
btf_verifier_log_type(env, v->t, "Invalid array of int");
|
|
return -EINVAL;
|
|
}
|
|
|
|
if (array->nelems && elem_size > U32_MAX / array->nelems) {
|
|
btf_verifier_log_type(env, v->t,
|
|
"Array size overflows U32_MAX");
|
|
return -EINVAL;
|
|
}
|
|
|
|
env_stack_pop_resolved(env, elem_type_id, elem_size * array->nelems);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static void btf_array_log(struct btf_verifier_env *env,
|
|
const struct btf_type *t)
|
|
{
|
|
const struct btf_array *array = btf_type_array(t);
|
|
|
|
btf_verifier_log(env, "type_id=%u index_type_id=%u nr_elems=%u",
|
|
array->type, array->index_type, array->nelems);
|
|
}
|
|
|
|
static void btf_array_seq_show(const struct btf *btf, const struct btf_type *t,
|
|
u32 type_id, void *data, u8 bits_offset,
|
|
struct seq_file *m)
|
|
{
|
|
const struct btf_array *array = btf_type_array(t);
|
|
const struct btf_kind_operations *elem_ops;
|
|
const struct btf_type *elem_type;
|
|
u32 i, elem_size, elem_type_id;
|
|
|
|
elem_type_id = array->type;
|
|
elem_type = btf_type_id_size(btf, &elem_type_id, &elem_size);
|
|
elem_ops = btf_type_ops(elem_type);
|
|
seq_puts(m, "[");
|
|
for (i = 0; i < array->nelems; i++) {
|
|
if (i)
|
|
seq_puts(m, ",");
|
|
|
|
elem_ops->seq_show(btf, elem_type, elem_type_id, data,
|
|
bits_offset, m);
|
|
data += elem_size;
|
|
}
|
|
seq_puts(m, "]");
|
|
}
|
|
|
|
static struct btf_kind_operations array_ops = {
|
|
.check_meta = btf_array_check_meta,
|
|
.resolve = btf_array_resolve,
|
|
.check_member = btf_array_check_member,
|
|
.check_kflag_member = btf_generic_check_kflag_member,
|
|
.log_details = btf_array_log,
|
|
.seq_show = btf_array_seq_show,
|
|
};
|
|
|
|
static int btf_struct_check_member(struct btf_verifier_env *env,
|
|
const struct btf_type *struct_type,
|
|
const struct btf_member *member,
|
|
const struct btf_type *member_type)
|
|
{
|
|
u32 struct_bits_off = member->offset;
|
|
u32 struct_size, bytes_offset;
|
|
|
|
if (BITS_PER_BYTE_MASKED(struct_bits_off)) {
|
|
btf_verifier_log_member(env, struct_type, member,
|
|
"Member is not byte aligned");
|
|
return -EINVAL;
|
|
}
|
|
|
|
struct_size = struct_type->size;
|
|
bytes_offset = BITS_ROUNDDOWN_BYTES(struct_bits_off);
|
|
if (struct_size - bytes_offset < member_type->size) {
|
|
btf_verifier_log_member(env, struct_type, member,
|
|
"Member exceeds struct_size");
|
|
return -EINVAL;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
static s32 btf_struct_check_meta(struct btf_verifier_env *env,
|
|
const struct btf_type *t,
|
|
u32 meta_left)
|
|
{
|
|
bool is_union = BTF_INFO_KIND(t->info) == BTF_KIND_UNION;
|
|
const struct btf_member *member;
|
|
u32 meta_needed, last_offset;
|
|
struct btf *btf = env->btf;
|
|
u32 struct_size = t->size;
|
|
u32 offset;
|
|
u16 i;
|
|
|
|
meta_needed = btf_type_vlen(t) * sizeof(*member);
|
|
if (meta_left < meta_needed) {
|
|
btf_verifier_log_basic(env, t,
|
|
"meta_left:%u meta_needed:%u",
|
|
meta_left, meta_needed);
|
|
return -EINVAL;
|
|
}
|
|
|
|
/* struct type either no name or a valid one */
|
|
if (t->name_off &&
|
|
!btf_name_valid_identifier(env->btf, t->name_off)) {
|
|
btf_verifier_log_type(env, t, "Invalid name");
|
|
return -EINVAL;
|
|
}
|
|
|
|
btf_verifier_log_type(env, t, NULL);
|
|
|
|
last_offset = 0;
|
|
for_each_member(i, t, member) {
|
|
if (!btf_name_offset_valid(btf, member->name_off)) {
|
|
btf_verifier_log_member(env, t, member,
|
|
"Invalid member name_offset:%u",
|
|
member->name_off);
|
|
return -EINVAL;
|
|
}
|
|
|
|
/* struct member either no name or a valid one */
|
|
if (member->name_off &&
|
|
!btf_name_valid_identifier(btf, member->name_off)) {
|
|
btf_verifier_log_member(env, t, member, "Invalid name");
|
|
return -EINVAL;
|
|
}
|
|
/* A member cannot be in type void */
|
|
if (!member->type || !BTF_TYPE_ID_VALID(member->type)) {
|
|
btf_verifier_log_member(env, t, member,
|
|
"Invalid type_id");
|
|
return -EINVAL;
|
|
}
|
|
|
|
offset = btf_member_bit_offset(t, member);
|
|
if (is_union && offset) {
|
|
btf_verifier_log_member(env, t, member,
|
|
"Invalid member bits_offset");
|
|
return -EINVAL;
|
|
}
|
|
|
|
/*
|
|
* ">" instead of ">=" because the last member could be
|
|
* "char a[0];"
|
|
*/
|
|
if (last_offset > offset) {
|
|
btf_verifier_log_member(env, t, member,
|
|
"Invalid member bits_offset");
|
|
return -EINVAL;
|
|
}
|
|
|
|
if (BITS_ROUNDUP_BYTES(offset) > struct_size) {
|
|
btf_verifier_log_member(env, t, member,
|
|
"Member bits_offset exceeds its struct size");
|
|
return -EINVAL;
|
|
}
|
|
|
|
btf_verifier_log_member(env, t, member, NULL);
|
|
last_offset = offset;
|
|
}
|
|
|
|
return meta_needed;
|
|
}
|
|
|
|
static int btf_struct_resolve(struct btf_verifier_env *env,
|
|
const struct resolve_vertex *v)
|
|
{
|
|
const struct btf_member *member;
|
|
int err;
|
|
u16 i;
|
|
|
|
/* Before continue resolving the next_member,
|
|
* ensure the last member is indeed resolved to a
|
|
* type with size info.
|
|
*/
|
|
if (v->next_member) {
|
|
const struct btf_type *last_member_type;
|
|
const struct btf_member *last_member;
|
|
u16 last_member_type_id;
|
|
|
|
last_member = btf_type_member(v->t) + v->next_member - 1;
|
|
last_member_type_id = last_member->type;
|
|
if (WARN_ON_ONCE(!env_type_is_resolved(env,
|
|
last_member_type_id)))
|
|
return -EINVAL;
|
|
|
|
last_member_type = btf_type_by_id(env->btf,
|
|
last_member_type_id);
|
|
if (btf_type_kflag(v->t))
|
|
err = btf_type_ops(last_member_type)->check_kflag_member(env, v->t,
|
|
last_member,
|
|
last_member_type);
|
|
else
|
|
err = btf_type_ops(last_member_type)->check_member(env, v->t,
|
|
last_member,
|
|
last_member_type);
|
|
if (err)
|
|
return err;
|
|
}
|
|
|
|
for_each_member_from(i, v->next_member, v->t, member) {
|
|
u32 member_type_id = member->type;
|
|
const struct btf_type *member_type = btf_type_by_id(env->btf,
|
|
member_type_id);
|
|
|
|
if (btf_type_nosize_or_null(member_type) ||
|
|
btf_type_is_resolve_source_only(member_type)) {
|
|
btf_verifier_log_member(env, v->t, member,
|
|
"Invalid member");
|
|
return -EINVAL;
|
|
}
|
|
|
|
if (!env_type_is_resolve_sink(env, member_type) &&
|
|
!env_type_is_resolved(env, member_type_id)) {
|
|
env_stack_set_next_member(env, i + 1);
|
|
return env_stack_push(env, member_type, member_type_id);
|
|
}
|
|
|
|
if (btf_type_kflag(v->t))
|
|
err = btf_type_ops(member_type)->check_kflag_member(env, v->t,
|
|
member,
|
|
member_type);
|
|
else
|
|
err = btf_type_ops(member_type)->check_member(env, v->t,
|
|
member,
|
|
member_type);
|
|
if (err)
|
|
return err;
|
|
}
|
|
|
|
env_stack_pop_resolved(env, 0, 0);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static void btf_struct_log(struct btf_verifier_env *env,
|
|
const struct btf_type *t)
|
|
{
|
|
btf_verifier_log(env, "size=%u vlen=%u", t->size, btf_type_vlen(t));
|
|
}
|
|
|
|
/* find 'struct bpf_spin_lock' in map value.
|
|
* return >= 0 offset if found
|
|
* and < 0 in case of error
|
|
*/
|
|
int btf_find_spin_lock(const struct btf *btf, const struct btf_type *t)
|
|
{
|
|
const struct btf_member *member;
|
|
u32 i, off = -ENOENT;
|
|
|
|
if (!__btf_type_is_struct(t))
|
|
return -EINVAL;
|
|
|
|
for_each_member(i, t, member) {
|
|
const struct btf_type *member_type = btf_type_by_id(btf,
|
|
member->type);
|
|
if (!__btf_type_is_struct(member_type))
|
|
continue;
|
|
if (member_type->size != sizeof(struct bpf_spin_lock))
|
|
continue;
|
|
if (strcmp(__btf_name_by_offset(btf, member_type->name_off),
|
|
"bpf_spin_lock"))
|
|
continue;
|
|
if (off != -ENOENT)
|
|
/* only one 'struct bpf_spin_lock' is allowed */
|
|
return -E2BIG;
|
|
off = btf_member_bit_offset(t, member);
|
|
if (off % 8)
|
|
/* valid C code cannot generate such BTF */
|
|
return -EINVAL;
|
|
off /= 8;
|
|
if (off % __alignof__(struct bpf_spin_lock))
|
|
/* valid struct bpf_spin_lock will be 4 byte aligned */
|
|
return -EINVAL;
|
|
}
|
|
return off;
|
|
}
|
|
|
|
static void btf_struct_seq_show(const struct btf *btf, const struct btf_type *t,
|
|
u32 type_id, void *data, u8 bits_offset,
|
|
struct seq_file *m)
|
|
{
|
|
const char *seq = BTF_INFO_KIND(t->info) == BTF_KIND_UNION ? "|" : ",";
|
|
const struct btf_member *member;
|
|
u32 i;
|
|
|
|
seq_puts(m, "{");
|
|
for_each_member(i, t, member) {
|
|
const struct btf_type *member_type = btf_type_by_id(btf,
|
|
member->type);
|
|
const struct btf_kind_operations *ops;
|
|
u32 member_offset, bitfield_size;
|
|
u32 bytes_offset;
|
|
u8 bits8_offset;
|
|
|
|
if (i)
|
|
seq_puts(m, seq);
|
|
|
|
member_offset = btf_member_bit_offset(t, member);
|
|
bitfield_size = btf_member_bitfield_size(t, member);
|
|
bytes_offset = BITS_ROUNDDOWN_BYTES(member_offset);
|
|
bits8_offset = BITS_PER_BYTE_MASKED(member_offset);
|
|
if (bitfield_size) {
|
|
btf_bitfield_seq_show(data + bytes_offset, bits8_offset,
|
|
bitfield_size, m);
|
|
} else {
|
|
ops = btf_type_ops(member_type);
|
|
ops->seq_show(btf, member_type, member->type,
|
|
data + bytes_offset, bits8_offset, m);
|
|
}
|
|
}
|
|
seq_puts(m, "}");
|
|
}
|
|
|
|
static struct btf_kind_operations struct_ops = {
|
|
.check_meta = btf_struct_check_meta,
|
|
.resolve = btf_struct_resolve,
|
|
.check_member = btf_struct_check_member,
|
|
.check_kflag_member = btf_generic_check_kflag_member,
|
|
.log_details = btf_struct_log,
|
|
.seq_show = btf_struct_seq_show,
|
|
};
|
|
|
|
static int btf_enum_check_member(struct btf_verifier_env *env,
|
|
const struct btf_type *struct_type,
|
|
const struct btf_member *member,
|
|
const struct btf_type *member_type)
|
|
{
|
|
u32 struct_bits_off = member->offset;
|
|
u32 struct_size, bytes_offset;
|
|
|
|
if (BITS_PER_BYTE_MASKED(struct_bits_off)) {
|
|
btf_verifier_log_member(env, struct_type, member,
|
|
"Member is not byte aligned");
|
|
return -EINVAL;
|
|
}
|
|
|
|
struct_size = struct_type->size;
|
|
bytes_offset = BITS_ROUNDDOWN_BYTES(struct_bits_off);
|
|
if (struct_size - bytes_offset < sizeof(int)) {
|
|
btf_verifier_log_member(env, struct_type, member,
|
|
"Member exceeds struct_size");
|
|
return -EINVAL;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int btf_enum_check_kflag_member(struct btf_verifier_env *env,
|
|
const struct btf_type *struct_type,
|
|
const struct btf_member *member,
|
|
const struct btf_type *member_type)
|
|
{
|
|
u32 struct_bits_off, nr_bits, bytes_end, struct_size;
|
|
u32 int_bitsize = sizeof(int) * BITS_PER_BYTE;
|
|
|
|
struct_bits_off = BTF_MEMBER_BIT_OFFSET(member->offset);
|
|
nr_bits = BTF_MEMBER_BITFIELD_SIZE(member->offset);
|
|
if (!nr_bits) {
|
|
if (BITS_PER_BYTE_MASKED(struct_bits_off)) {
|
|
btf_verifier_log_member(env, struct_type, member,
|
|
"Member is not byte aligned");
|
|
return -EINVAL;
|
|
}
|
|
|
|
nr_bits = int_bitsize;
|
|
} else if (nr_bits > int_bitsize) {
|
|
btf_verifier_log_member(env, struct_type, member,
|
|
"Invalid member bitfield_size");
|
|
return -EINVAL;
|
|
}
|
|
|
|
struct_size = struct_type->size;
|
|
bytes_end = BITS_ROUNDUP_BYTES(struct_bits_off + nr_bits);
|
|
if (struct_size < bytes_end) {
|
|
btf_verifier_log_member(env, struct_type, member,
|
|
"Member exceeds struct_size");
|
|
return -EINVAL;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
static s32 btf_enum_check_meta(struct btf_verifier_env *env,
|
|
const struct btf_type *t,
|
|
u32 meta_left)
|
|
{
|
|
const struct btf_enum *enums = btf_type_enum(t);
|
|
struct btf *btf = env->btf;
|
|
u16 i, nr_enums;
|
|
u32 meta_needed;
|
|
|
|
nr_enums = btf_type_vlen(t);
|
|
meta_needed = nr_enums * sizeof(*enums);
|
|
|
|
if (meta_left < meta_needed) {
|
|
btf_verifier_log_basic(env, t,
|
|
"meta_left:%u meta_needed:%u",
|
|
meta_left, meta_needed);
|
|
return -EINVAL;
|
|
}
|
|
|
|
if (btf_type_kflag(t)) {
|
|
btf_verifier_log_type(env, t, "Invalid btf_info kind_flag");
|
|
return -EINVAL;
|
|
}
|
|
|
|
if (t->size > 8 || !is_power_of_2(t->size)) {
|
|
btf_verifier_log_type(env, t, "Unexpected size");
|
|
return -EINVAL;
|
|
}
|
|
|
|
/* enum type either no name or a valid one */
|
|
if (t->name_off &&
|
|
!btf_name_valid_identifier(env->btf, t->name_off)) {
|
|
btf_verifier_log_type(env, t, "Invalid name");
|
|
return -EINVAL;
|
|
}
|
|
|
|
btf_verifier_log_type(env, t, NULL);
|
|
|
|
for (i = 0; i < nr_enums; i++) {
|
|
if (!btf_name_offset_valid(btf, enums[i].name_off)) {
|
|
btf_verifier_log(env, "\tInvalid name_offset:%u",
|
|
enums[i].name_off);
|
|
return -EINVAL;
|
|
}
|
|
|
|
/* enum member must have a valid name */
|
|
if (!enums[i].name_off ||
|
|
!btf_name_valid_identifier(btf, enums[i].name_off)) {
|
|
btf_verifier_log_type(env, t, "Invalid name");
|
|
return -EINVAL;
|
|
}
|
|
|
|
|
|
btf_verifier_log(env, "\t%s val=%d\n",
|
|
__btf_name_by_offset(btf, enums[i].name_off),
|
|
enums[i].val);
|
|
}
|
|
|
|
return meta_needed;
|
|
}
|
|
|
|
static void btf_enum_log(struct btf_verifier_env *env,
|
|
const struct btf_type *t)
|
|
{
|
|
btf_verifier_log(env, "size=%u vlen=%u", t->size, btf_type_vlen(t));
|
|
}
|
|
|
|
static void btf_enum_seq_show(const struct btf *btf, const struct btf_type *t,
|
|
u32 type_id, void *data, u8 bits_offset,
|
|
struct seq_file *m)
|
|
{
|
|
const struct btf_enum *enums = btf_type_enum(t);
|
|
u32 i, nr_enums = btf_type_vlen(t);
|
|
int v = *(int *)data;
|
|
|
|
for (i = 0; i < nr_enums; i++) {
|
|
if (v == enums[i].val) {
|
|
seq_printf(m, "%s",
|
|
__btf_name_by_offset(btf,
|
|
enums[i].name_off));
|
|
return;
|
|
}
|
|
}
|
|
|
|
seq_printf(m, "%d", v);
|
|
}
|
|
|
|
static struct btf_kind_operations enum_ops = {
|
|
.check_meta = btf_enum_check_meta,
|
|
.resolve = btf_df_resolve,
|
|
.check_member = btf_enum_check_member,
|
|
.check_kflag_member = btf_enum_check_kflag_member,
|
|
.log_details = btf_enum_log,
|
|
.seq_show = btf_enum_seq_show,
|
|
};
|
|
|
|
static s32 btf_func_proto_check_meta(struct btf_verifier_env *env,
|
|
const struct btf_type *t,
|
|
u32 meta_left)
|
|
{
|
|
u32 meta_needed = btf_type_vlen(t) * sizeof(struct btf_param);
|
|
|
|
if (meta_left < meta_needed) {
|
|
btf_verifier_log_basic(env, t,
|
|
"meta_left:%u meta_needed:%u",
|
|
meta_left, meta_needed);
|
|
return -EINVAL;
|
|
}
|
|
|
|
if (t->name_off) {
|
|
btf_verifier_log_type(env, t, "Invalid name");
|
|
return -EINVAL;
|
|
}
|
|
|
|
if (btf_type_kflag(t)) {
|
|
btf_verifier_log_type(env, t, "Invalid btf_info kind_flag");
|
|
return -EINVAL;
|
|
}
|
|
|
|
btf_verifier_log_type(env, t, NULL);
|
|
|
|
return meta_needed;
|
|
}
|
|
|
|
static void btf_func_proto_log(struct btf_verifier_env *env,
|
|
const struct btf_type *t)
|
|
{
|
|
const struct btf_param *args = (const struct btf_param *)(t + 1);
|
|
u16 nr_args = btf_type_vlen(t), i;
|
|
|
|
btf_verifier_log(env, "return=%u args=(", t->type);
|
|
if (!nr_args) {
|
|
btf_verifier_log(env, "void");
|
|
goto done;
|
|
}
|
|
|
|
if (nr_args == 1 && !args[0].type) {
|
|
/* Only one vararg */
|
|
btf_verifier_log(env, "vararg");
|
|
goto done;
|
|
}
|
|
|
|
btf_verifier_log(env, "%u %s", args[0].type,
|
|
__btf_name_by_offset(env->btf,
|
|
args[0].name_off));
|
|
for (i = 1; i < nr_args - 1; i++)
|
|
btf_verifier_log(env, ", %u %s", args[i].type,
|
|
__btf_name_by_offset(env->btf,
|
|
args[i].name_off));
|
|
|
|
if (nr_args > 1) {
|
|
const struct btf_param *last_arg = &args[nr_args - 1];
|
|
|
|
if (last_arg->type)
|
|
btf_verifier_log(env, ", %u %s", last_arg->type,
|
|
__btf_name_by_offset(env->btf,
|
|
last_arg->name_off));
|
|
else
|
|
btf_verifier_log(env, ", vararg");
|
|
}
|
|
|
|
done:
|
|
btf_verifier_log(env, ")");
|
|
}
|
|
|
|
static struct btf_kind_operations func_proto_ops = {
|
|
.check_meta = btf_func_proto_check_meta,
|
|
.resolve = btf_df_resolve,
|
|
/*
|
|
* BTF_KIND_FUNC_PROTO cannot be directly referred by
|
|
* a struct's member.
|
|
*
|
|
* It should be a funciton pointer instead.
|
|
* (i.e. struct's member -> BTF_KIND_PTR -> BTF_KIND_FUNC_PROTO)
|
|
*
|
|
* Hence, there is no btf_func_check_member().
|
|
*/
|
|
.check_member = btf_df_check_member,
|
|
.check_kflag_member = btf_df_check_kflag_member,
|
|
.log_details = btf_func_proto_log,
|
|
.seq_show = btf_df_seq_show,
|
|
};
|
|
|
|
static s32 btf_func_check_meta(struct btf_verifier_env *env,
|
|
const struct btf_type *t,
|
|
u32 meta_left)
|
|
{
|
|
if (!t->name_off ||
|
|
!btf_name_valid_identifier(env->btf, t->name_off)) {
|
|
btf_verifier_log_type(env, t, "Invalid name");
|
|
return -EINVAL;
|
|
}
|
|
|
|
if (btf_type_vlen(t)) {
|
|
btf_verifier_log_type(env, t, "vlen != 0");
|
|
return -EINVAL;
|
|
}
|
|
|
|
if (btf_type_kflag(t)) {
|
|
btf_verifier_log_type(env, t, "Invalid btf_info kind_flag");
|
|
return -EINVAL;
|
|
}
|
|
|
|
btf_verifier_log_type(env, t, NULL);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static struct btf_kind_operations func_ops = {
|
|
.check_meta = btf_func_check_meta,
|
|
.resolve = btf_df_resolve,
|
|
.check_member = btf_df_check_member,
|
|
.check_kflag_member = btf_df_check_kflag_member,
|
|
.log_details = btf_ref_type_log,
|
|
.seq_show = btf_df_seq_show,
|
|
};
|
|
|
|
static s32 btf_var_check_meta(struct btf_verifier_env *env,
|
|
const struct btf_type *t,
|
|
u32 meta_left)
|
|
{
|
|
const struct btf_var *var;
|
|
u32 meta_needed = sizeof(*var);
|
|
|
|
if (meta_left < meta_needed) {
|
|
btf_verifier_log_basic(env, t,
|
|
"meta_left:%u meta_needed:%u",
|
|
meta_left, meta_needed);
|
|
return -EINVAL;
|
|
}
|
|
|
|
if (btf_type_vlen(t)) {
|
|
btf_verifier_log_type(env, t, "vlen != 0");
|
|
return -EINVAL;
|
|
}
|
|
|
|
if (btf_type_kflag(t)) {
|
|
btf_verifier_log_type(env, t, "Invalid btf_info kind_flag");
|
|
return -EINVAL;
|
|
}
|
|
|
|
if (!t->name_off ||
|
|
!__btf_name_valid(env->btf, t->name_off, true)) {
|
|
btf_verifier_log_type(env, t, "Invalid name");
|
|
return -EINVAL;
|
|
}
|
|
|
|
/* A var cannot be in type void */
|
|
if (!t->type || !BTF_TYPE_ID_VALID(t->type)) {
|
|
btf_verifier_log_type(env, t, "Invalid type_id");
|
|
return -EINVAL;
|
|
}
|
|
|
|
var = btf_type_var(t);
|
|
if (var->linkage != BTF_VAR_STATIC &&
|
|
var->linkage != BTF_VAR_GLOBAL_ALLOCATED) {
|
|
btf_verifier_log_type(env, t, "Linkage not supported");
|
|
return -EINVAL;
|
|
}
|
|
|
|
btf_verifier_log_type(env, t, NULL);
|
|
|
|
return meta_needed;
|
|
}
|
|
|
|
static void btf_var_log(struct btf_verifier_env *env, const struct btf_type *t)
|
|
{
|
|
const struct btf_var *var = btf_type_var(t);
|
|
|
|
btf_verifier_log(env, "type_id=%u linkage=%u", t->type, var->linkage);
|
|
}
|
|
|
|
static const struct btf_kind_operations var_ops = {
|
|
.check_meta = btf_var_check_meta,
|
|
.resolve = btf_var_resolve,
|
|
.check_member = btf_df_check_member,
|
|
.check_kflag_member = btf_df_check_kflag_member,
|
|
.log_details = btf_var_log,
|
|
.seq_show = btf_var_seq_show,
|
|
};
|
|
|
|
static s32 btf_datasec_check_meta(struct btf_verifier_env *env,
|
|
const struct btf_type *t,
|
|
u32 meta_left)
|
|
{
|
|
const struct btf_var_secinfo *vsi;
|
|
u64 last_vsi_end_off = 0, sum = 0;
|
|
u32 i, meta_needed;
|
|
|
|
meta_needed = btf_type_vlen(t) * sizeof(*vsi);
|
|
if (meta_left < meta_needed) {
|
|
btf_verifier_log_basic(env, t,
|
|
"meta_left:%u meta_needed:%u",
|
|
meta_left, meta_needed);
|
|
return -EINVAL;
|
|
}
|
|
|
|
if (!btf_type_vlen(t)) {
|
|
btf_verifier_log_type(env, t, "vlen == 0");
|
|
return -EINVAL;
|
|
}
|
|
|
|
if (!t->size) {
|
|
btf_verifier_log_type(env, t, "size == 0");
|
|
return -EINVAL;
|
|
}
|
|
|
|
if (btf_type_kflag(t)) {
|
|
btf_verifier_log_type(env, t, "Invalid btf_info kind_flag");
|
|
return -EINVAL;
|
|
}
|
|
|
|
if (!t->name_off ||
|
|
!btf_name_valid_section(env->btf, t->name_off)) {
|
|
btf_verifier_log_type(env, t, "Invalid name");
|
|
return -EINVAL;
|
|
}
|
|
|
|
btf_verifier_log_type(env, t, NULL);
|
|
|
|
for_each_vsi(i, t, vsi) {
|
|
/* A var cannot be in type void */
|
|
if (!vsi->type || !BTF_TYPE_ID_VALID(vsi->type)) {
|
|
btf_verifier_log_vsi(env, t, vsi,
|
|
"Invalid type_id");
|
|
return -EINVAL;
|
|
}
|
|
|
|
if (vsi->offset < last_vsi_end_off || vsi->offset >= t->size) {
|
|
btf_verifier_log_vsi(env, t, vsi,
|
|
"Invalid offset");
|
|
return -EINVAL;
|
|
}
|
|
|
|
if (!vsi->size || vsi->size > t->size) {
|
|
btf_verifier_log_vsi(env, t, vsi,
|
|
"Invalid size");
|
|
return -EINVAL;
|
|
}
|
|
|
|
last_vsi_end_off = vsi->offset + vsi->size;
|
|
if (last_vsi_end_off > t->size) {
|
|
btf_verifier_log_vsi(env, t, vsi,
|
|
"Invalid offset+size");
|
|
return -EINVAL;
|
|
}
|
|
|
|
btf_verifier_log_vsi(env, t, vsi, NULL);
|
|
sum += vsi->size;
|
|
}
|
|
|
|
if (t->size < sum) {
|
|
btf_verifier_log_type(env, t, "Invalid btf_info size");
|
|
return -EINVAL;
|
|
}
|
|
|
|
return meta_needed;
|
|
}
|
|
|
|
static int btf_datasec_resolve(struct btf_verifier_env *env,
|
|
const struct resolve_vertex *v)
|
|
{
|
|
const struct btf_var_secinfo *vsi;
|
|
struct btf *btf = env->btf;
|
|
u16 i;
|
|
|
|
for_each_vsi_from(i, v->next_member, v->t, vsi) {
|
|
u32 var_type_id = vsi->type, type_id, type_size = 0;
|
|
const struct btf_type *var_type = btf_type_by_id(env->btf,
|
|
var_type_id);
|
|
if (!var_type || !btf_type_is_var(var_type)) {
|
|
btf_verifier_log_vsi(env, v->t, vsi,
|
|
"Not a VAR kind member");
|
|
return -EINVAL;
|
|
}
|
|
|
|
if (!env_type_is_resolve_sink(env, var_type) &&
|
|
!env_type_is_resolved(env, var_type_id)) {
|
|
env_stack_set_next_member(env, i + 1);
|
|
return env_stack_push(env, var_type, var_type_id);
|
|
}
|
|
|
|
type_id = var_type->type;
|
|
if (!btf_type_id_size(btf, &type_id, &type_size)) {
|
|
btf_verifier_log_vsi(env, v->t, vsi, "Invalid type");
|
|
return -EINVAL;
|
|
}
|
|
|
|
if (vsi->size < type_size) {
|
|
btf_verifier_log_vsi(env, v->t, vsi, "Invalid size");
|
|
return -EINVAL;
|
|
}
|
|
}
|
|
|
|
env_stack_pop_resolved(env, 0, 0);
|
|
return 0;
|
|
}
|
|
|
|
static void btf_datasec_log(struct btf_verifier_env *env,
|
|
const struct btf_type *t)
|
|
{
|
|
btf_verifier_log(env, "size=%u vlen=%u", t->size, btf_type_vlen(t));
|
|
}
|
|
|
|
static void btf_datasec_seq_show(const struct btf *btf,
|
|
const struct btf_type *t, u32 type_id,
|
|
void *data, u8 bits_offset,
|
|
struct seq_file *m)
|
|
{
|
|
const struct btf_var_secinfo *vsi;
|
|
const struct btf_type *var;
|
|
u32 i;
|
|
|
|
seq_printf(m, "section (\"%s\") = {", __btf_name_by_offset(btf, t->name_off));
|
|
for_each_vsi(i, t, vsi) {
|
|
var = btf_type_by_id(btf, vsi->type);
|
|
if (i)
|
|
seq_puts(m, ",");
|
|
btf_type_ops(var)->seq_show(btf, var, vsi->type,
|
|
data + vsi->offset, bits_offset, m);
|
|
}
|
|
seq_puts(m, "}");
|
|
}
|
|
|
|
static const struct btf_kind_operations datasec_ops = {
|
|
.check_meta = btf_datasec_check_meta,
|
|
.resolve = btf_datasec_resolve,
|
|
.check_member = btf_df_check_member,
|
|
.check_kflag_member = btf_df_check_kflag_member,
|
|
.log_details = btf_datasec_log,
|
|
.seq_show = btf_datasec_seq_show,
|
|
};
|
|
|
|
static int btf_func_proto_check(struct btf_verifier_env *env,
|
|
const struct btf_type *t)
|
|
{
|
|
const struct btf_type *ret_type;
|
|
const struct btf_param *args;
|
|
const struct btf *btf;
|
|
u16 nr_args, i;
|
|
int err;
|
|
|
|
btf = env->btf;
|
|
args = (const struct btf_param *)(t + 1);
|
|
nr_args = btf_type_vlen(t);
|
|
|
|
/* Check func return type which could be "void" (t->type == 0) */
|
|
if (t->type) {
|
|
u32 ret_type_id = t->type;
|
|
|
|
ret_type = btf_type_by_id(btf, ret_type_id);
|
|
if (!ret_type) {
|
|
btf_verifier_log_type(env, t, "Invalid return type");
|
|
return -EINVAL;
|
|
}
|
|
|
|
if (btf_type_needs_resolve(ret_type) &&
|
|
!env_type_is_resolved(env, ret_type_id)) {
|
|
err = btf_resolve(env, ret_type, ret_type_id);
|
|
if (err)
|
|
return err;
|
|
}
|
|
|
|
/* Ensure the return type is a type that has a size */
|
|
if (!btf_type_id_size(btf, &ret_type_id, NULL)) {
|
|
btf_verifier_log_type(env, t, "Invalid return type");
|
|
return -EINVAL;
|
|
}
|
|
}
|
|
|
|
if (!nr_args)
|
|
return 0;
|
|
|
|
/* Last func arg type_id could be 0 if it is a vararg */
|
|
if (!args[nr_args - 1].type) {
|
|
if (args[nr_args - 1].name_off) {
|
|
btf_verifier_log_type(env, t, "Invalid arg#%u",
|
|
nr_args);
|
|
return -EINVAL;
|
|
}
|
|
nr_args--;
|
|
}
|
|
|
|
err = 0;
|
|
for (i = 0; i < nr_args; i++) {
|
|
const struct btf_type *arg_type;
|
|
u32 arg_type_id;
|
|
|
|
arg_type_id = args[i].type;
|
|
arg_type = btf_type_by_id(btf, arg_type_id);
|
|
if (!arg_type) {
|
|
btf_verifier_log_type(env, t, "Invalid arg#%u", i + 1);
|
|
err = -EINVAL;
|
|
break;
|
|
}
|
|
|
|
if (args[i].name_off &&
|
|
(!btf_name_offset_valid(btf, args[i].name_off) ||
|
|
!btf_name_valid_identifier(btf, args[i].name_off))) {
|
|
btf_verifier_log_type(env, t,
|
|
"Invalid arg#%u", i + 1);
|
|
err = -EINVAL;
|
|
break;
|
|
}
|
|
|
|
if (btf_type_needs_resolve(arg_type) &&
|
|
!env_type_is_resolved(env, arg_type_id)) {
|
|
err = btf_resolve(env, arg_type, arg_type_id);
|
|
if (err)
|
|
break;
|
|
}
|
|
|
|
if (!btf_type_id_size(btf, &arg_type_id, NULL)) {
|
|
btf_verifier_log_type(env, t, "Invalid arg#%u", i + 1);
|
|
err = -EINVAL;
|
|
break;
|
|
}
|
|
}
|
|
|
|
return err;
|
|
}
|
|
|
|
static int btf_func_check(struct btf_verifier_env *env,
|
|
const struct btf_type *t)
|
|
{
|
|
const struct btf_type *proto_type;
|
|
const struct btf_param *args;
|
|
const struct btf *btf;
|
|
u16 nr_args, i;
|
|
|
|
btf = env->btf;
|
|
proto_type = btf_type_by_id(btf, t->type);
|
|
|
|
if (!proto_type || !btf_type_is_func_proto(proto_type)) {
|
|
btf_verifier_log_type(env, t, "Invalid type_id");
|
|
return -EINVAL;
|
|
}
|
|
|
|
args = (const struct btf_param *)(proto_type + 1);
|
|
nr_args = btf_type_vlen(proto_type);
|
|
for (i = 0; i < nr_args; i++) {
|
|
if (!args[i].name_off && args[i].type) {
|
|
btf_verifier_log_type(env, t, "Invalid arg#%u", i + 1);
|
|
return -EINVAL;
|
|
}
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
static const struct btf_kind_operations * const kind_ops[NR_BTF_KINDS] = {
|
|
[BTF_KIND_INT] = &int_ops,
|
|
[BTF_KIND_PTR] = &ptr_ops,
|
|
[BTF_KIND_ARRAY] = &array_ops,
|
|
[BTF_KIND_STRUCT] = &struct_ops,
|
|
[BTF_KIND_UNION] = &struct_ops,
|
|
[BTF_KIND_ENUM] = &enum_ops,
|
|
[BTF_KIND_FWD] = &fwd_ops,
|
|
[BTF_KIND_TYPEDEF] = &modifier_ops,
|
|
[BTF_KIND_VOLATILE] = &modifier_ops,
|
|
[BTF_KIND_CONST] = &modifier_ops,
|
|
[BTF_KIND_RESTRICT] = &modifier_ops,
|
|
[BTF_KIND_FUNC] = &func_ops,
|
|
[BTF_KIND_FUNC_PROTO] = &func_proto_ops,
|
|
[BTF_KIND_VAR] = &var_ops,
|
|
[BTF_KIND_DATASEC] = &datasec_ops,
|
|
};
|
|
|
|
static s32 btf_check_meta(struct btf_verifier_env *env,
|
|
const struct btf_type *t,
|
|
u32 meta_left)
|
|
{
|
|
u32 saved_meta_left = meta_left;
|
|
s32 var_meta_size;
|
|
|
|
if (meta_left < sizeof(*t)) {
|
|
btf_verifier_log(env, "[%u] meta_left:%u meta_needed:%zu",
|
|
env->log_type_id, meta_left, sizeof(*t));
|
|
return -EINVAL;
|
|
}
|
|
meta_left -= sizeof(*t);
|
|
|
|
if (t->info & ~BTF_INFO_MASK) {
|
|
btf_verifier_log(env, "[%u] Invalid btf_info:%x",
|
|
env->log_type_id, t->info);
|
|
return -EINVAL;
|
|
}
|
|
|
|
if (BTF_INFO_KIND(t->info) > BTF_KIND_MAX ||
|
|
BTF_INFO_KIND(t->info) == BTF_KIND_UNKN) {
|
|
btf_verifier_log(env, "[%u] Invalid kind:%u",
|
|
env->log_type_id, BTF_INFO_KIND(t->info));
|
|
return -EINVAL;
|
|
}
|
|
|
|
if (!btf_name_offset_valid(env->btf, t->name_off)) {
|
|
btf_verifier_log(env, "[%u] Invalid name_offset:%u",
|
|
env->log_type_id, t->name_off);
|
|
return -EINVAL;
|
|
}
|
|
|
|
var_meta_size = btf_type_ops(t)->check_meta(env, t, meta_left);
|
|
if (var_meta_size < 0)
|
|
return var_meta_size;
|
|
|
|
meta_left -= var_meta_size;
|
|
|
|
return saved_meta_left - meta_left;
|
|
}
|
|
|
|
static int btf_check_all_metas(struct btf_verifier_env *env)
|
|
{
|
|
struct btf *btf = env->btf;
|
|
struct btf_header *hdr;
|
|
void *cur, *end;
|
|
|
|
hdr = &btf->hdr;
|
|
cur = btf->nohdr_data + hdr->type_off;
|
|
end = cur + hdr->type_len;
|
|
|
|
env->log_type_id = 1;
|
|
while (cur < end) {
|
|
struct btf_type *t = cur;
|
|
s32 meta_size;
|
|
|
|
meta_size = btf_check_meta(env, t, end - cur);
|
|
if (meta_size < 0)
|
|
return meta_size;
|
|
|
|
btf_add_type(env, t);
|
|
cur += meta_size;
|
|
env->log_type_id++;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
static bool btf_resolve_valid(struct btf_verifier_env *env,
|
|
const struct btf_type *t,
|
|
u32 type_id)
|
|
{
|
|
struct btf *btf = env->btf;
|
|
|
|
if (!env_type_is_resolved(env, type_id))
|
|
return false;
|
|
|
|
if (btf_type_is_struct(t) || btf_type_is_datasec(t))
|
|
return !btf->resolved_ids[type_id] &&
|
|
!btf->resolved_sizes[type_id];
|
|
|
|
if (btf_type_is_modifier(t) || btf_type_is_ptr(t) ||
|
|
btf_type_is_var(t)) {
|
|
t = btf_type_id_resolve(btf, &type_id);
|
|
return t &&
|
|
!btf_type_is_modifier(t) &&
|
|
!btf_type_is_var(t) &&
|
|
!btf_type_is_datasec(t);
|
|
}
|
|
|
|
if (btf_type_is_array(t)) {
|
|
const struct btf_array *array = btf_type_array(t);
|
|
const struct btf_type *elem_type;
|
|
u32 elem_type_id = array->type;
|
|
u32 elem_size;
|
|
|
|
elem_type = btf_type_id_size(btf, &elem_type_id, &elem_size);
|
|
return elem_type && !btf_type_is_modifier(elem_type) &&
|
|
(array->nelems * elem_size ==
|
|
btf->resolved_sizes[type_id]);
|
|
}
|
|
|
|
return false;
|
|
}
|
|
|
|
static int btf_resolve(struct btf_verifier_env *env,
|
|
const struct btf_type *t, u32 type_id)
|
|
{
|
|
u32 save_log_type_id = env->log_type_id;
|
|
const struct resolve_vertex *v;
|
|
int err = 0;
|
|
|
|
env->resolve_mode = RESOLVE_TBD;
|
|
env_stack_push(env, t, type_id);
|
|
while (!err && (v = env_stack_peak(env))) {
|
|
env->log_type_id = v->type_id;
|
|
err = btf_type_ops(v->t)->resolve(env, v);
|
|
}
|
|
|
|
env->log_type_id = type_id;
|
|
if (err == -E2BIG) {
|
|
btf_verifier_log_type(env, t,
|
|
"Exceeded max resolving depth:%u",
|
|
MAX_RESOLVE_DEPTH);
|
|
} else if (err == -EEXIST) {
|
|
btf_verifier_log_type(env, t, "Loop detected");
|
|
}
|
|
|
|
/* Final sanity check */
|
|
if (!err && !btf_resolve_valid(env, t, type_id)) {
|
|
btf_verifier_log_type(env, t, "Invalid resolve state");
|
|
err = -EINVAL;
|
|
}
|
|
|
|
env->log_type_id = save_log_type_id;
|
|
return err;
|
|
}
|
|
|
|
static int btf_check_all_types(struct btf_verifier_env *env)
|
|
{
|
|
struct btf *btf = env->btf;
|
|
u32 type_id;
|
|
int err;
|
|
|
|
err = env_resolve_init(env);
|
|
if (err)
|
|
return err;
|
|
|
|
env->phase++;
|
|
for (type_id = 1; type_id <= btf->nr_types; type_id++) {
|
|
const struct btf_type *t = btf_type_by_id(btf, type_id);
|
|
|
|
env->log_type_id = type_id;
|
|
if (btf_type_needs_resolve(t) &&
|
|
!env_type_is_resolved(env, type_id)) {
|
|
err = btf_resolve(env, t, type_id);
|
|
if (err)
|
|
return err;
|
|
}
|
|
|
|
if (btf_type_is_func_proto(t)) {
|
|
err = btf_func_proto_check(env, t);
|
|
if (err)
|
|
return err;
|
|
}
|
|
|
|
if (btf_type_is_func(t)) {
|
|
err = btf_func_check(env, t);
|
|
if (err)
|
|
return err;
|
|
}
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int btf_parse_type_sec(struct btf_verifier_env *env)
|
|
{
|
|
const struct btf_header *hdr = &env->btf->hdr;
|
|
int err;
|
|
|
|
/* Type section must align to 4 bytes */
|
|
if (hdr->type_off & (sizeof(u32) - 1)) {
|
|
btf_verifier_log(env, "Unaligned type_off");
|
|
return -EINVAL;
|
|
}
|
|
|
|
if (!hdr->type_len) {
|
|
btf_verifier_log(env, "No type found");
|
|
return -EINVAL;
|
|
}
|
|
|
|
err = btf_check_all_metas(env);
|
|
if (err)
|
|
return err;
|
|
|
|
return btf_check_all_types(env);
|
|
}
|
|
|
|
static int btf_parse_str_sec(struct btf_verifier_env *env)
|
|
{
|
|
const struct btf_header *hdr;
|
|
struct btf *btf = env->btf;
|
|
const char *start, *end;
|
|
|
|
hdr = &btf->hdr;
|
|
start = btf->nohdr_data + hdr->str_off;
|
|
end = start + hdr->str_len;
|
|
|
|
if (end != btf->data + btf->data_size) {
|
|
btf_verifier_log(env, "String section is not at the end");
|
|
return -EINVAL;
|
|
}
|
|
|
|
if (!hdr->str_len || hdr->str_len - 1 > BTF_MAX_NAME_OFFSET ||
|
|
start[0] || end[-1]) {
|
|
btf_verifier_log(env, "Invalid string section");
|
|
return -EINVAL;
|
|
}
|
|
|
|
btf->strings = start;
|
|
|
|
return 0;
|
|
}
|
|
|
|
static const size_t btf_sec_info_offset[] = {
|
|
offsetof(struct btf_header, type_off),
|
|
offsetof(struct btf_header, str_off),
|
|
};
|
|
|
|
static int btf_sec_info_cmp(const void *a, const void *b)
|
|
{
|
|
const struct btf_sec_info *x = a;
|
|
const struct btf_sec_info *y = b;
|
|
|
|
return (int)(x->off - y->off) ? : (int)(x->len - y->len);
|
|
}
|
|
|
|
static int btf_check_sec_info(struct btf_verifier_env *env,
|
|
u32 btf_data_size)
|
|
{
|
|
struct btf_sec_info secs[ARRAY_SIZE(btf_sec_info_offset)];
|
|
u32 total, expected_total, i;
|
|
const struct btf_header *hdr;
|
|
const struct btf *btf;
|
|
|
|
btf = env->btf;
|
|
hdr = &btf->hdr;
|
|
|
|
/* Populate the secs from hdr */
|
|
for (i = 0; i < ARRAY_SIZE(btf_sec_info_offset); i++)
|
|
secs[i] = *(struct btf_sec_info *)((void *)hdr +
|
|
btf_sec_info_offset[i]);
|
|
|
|
sort(secs, ARRAY_SIZE(btf_sec_info_offset),
|
|
sizeof(struct btf_sec_info), btf_sec_info_cmp, NULL);
|
|
|
|
/* Check for gaps and overlap among sections */
|
|
total = 0;
|
|
expected_total = btf_data_size - hdr->hdr_len;
|
|
for (i = 0; i < ARRAY_SIZE(btf_sec_info_offset); i++) {
|
|
if (expected_total < secs[i].off) {
|
|
btf_verifier_log(env, "Invalid section offset");
|
|
return -EINVAL;
|
|
}
|
|
if (total < secs[i].off) {
|
|
/* gap */
|
|
btf_verifier_log(env, "Unsupported section found");
|
|
return -EINVAL;
|
|
}
|
|
if (total > secs[i].off) {
|
|
btf_verifier_log(env, "Section overlap found");
|
|
return -EINVAL;
|
|
}
|
|
if (expected_total - total < secs[i].len) {
|
|
btf_verifier_log(env,
|
|
"Total section length too long");
|
|
return -EINVAL;
|
|
}
|
|
total += secs[i].len;
|
|
}
|
|
|
|
/* There is data other than hdr and known sections */
|
|
if (expected_total != total) {
|
|
btf_verifier_log(env, "Unsupported section found");
|
|
return -EINVAL;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int btf_parse_hdr(struct btf_verifier_env *env)
|
|
{
|
|
u32 hdr_len, hdr_copy, btf_data_size;
|
|
const struct btf_header *hdr;
|
|
struct btf *btf;
|
|
int err;
|
|
|
|
btf = env->btf;
|
|
btf_data_size = btf->data_size;
|
|
|
|
if (btf_data_size <
|
|
offsetof(struct btf_header, hdr_len) + sizeof(hdr->hdr_len)) {
|
|
btf_verifier_log(env, "hdr_len not found");
|
|
return -EINVAL;
|
|
}
|
|
|
|
hdr = btf->data;
|
|
hdr_len = hdr->hdr_len;
|
|
if (btf_data_size < hdr_len) {
|
|
btf_verifier_log(env, "btf_header not found");
|
|
return -EINVAL;
|
|
}
|
|
|
|
/* Ensure the unsupported header fields are zero */
|
|
if (hdr_len > sizeof(btf->hdr)) {
|
|
u8 *expected_zero = btf->data + sizeof(btf->hdr);
|
|
u8 *end = btf->data + hdr_len;
|
|
|
|
for (; expected_zero < end; expected_zero++) {
|
|
if (*expected_zero) {
|
|
btf_verifier_log(env, "Unsupported btf_header");
|
|
return -E2BIG;
|
|
}
|
|
}
|
|
}
|
|
|
|
hdr_copy = min_t(u32, hdr_len, sizeof(btf->hdr));
|
|
memcpy(&btf->hdr, btf->data, hdr_copy);
|
|
|
|
hdr = &btf->hdr;
|
|
|
|
btf_verifier_log_hdr(env, btf_data_size);
|
|
|
|
if (hdr->magic != BTF_MAGIC) {
|
|
btf_verifier_log(env, "Invalid magic");
|
|
return -EINVAL;
|
|
}
|
|
|
|
if (hdr->version != BTF_VERSION) {
|
|
btf_verifier_log(env, "Unsupported version");
|
|
return -ENOTSUPP;
|
|
}
|
|
|
|
if (hdr->flags) {
|
|
btf_verifier_log(env, "Unsupported flags");
|
|
return -ENOTSUPP;
|
|
}
|
|
|
|
if (btf_data_size == hdr->hdr_len) {
|
|
btf_verifier_log(env, "No data");
|
|
return -EINVAL;
|
|
}
|
|
|
|
err = btf_check_sec_info(env, btf_data_size);
|
|
if (err)
|
|
return err;
|
|
|
|
return 0;
|
|
}
|
|
|
|
static struct btf *btf_parse(void __user *btf_data, u32 btf_data_size,
|
|
u32 log_level, char __user *log_ubuf, u32 log_size)
|
|
{
|
|
struct btf_verifier_env *env = NULL;
|
|
struct bpf_verifier_log *log;
|
|
struct btf *btf = NULL;
|
|
u8 *data;
|
|
int err;
|
|
|
|
if (btf_data_size > BTF_MAX_SIZE)
|
|
return ERR_PTR(-E2BIG);
|
|
|
|
env = kzalloc(sizeof(*env), GFP_KERNEL | __GFP_NOWARN);
|
|
if (!env)
|
|
return ERR_PTR(-ENOMEM);
|
|
|
|
log = &env->log;
|
|
if (log_level || log_ubuf || log_size) {
|
|
/* user requested verbose verifier output
|
|
* and supplied buffer to store the verification trace
|
|
*/
|
|
log->level = log_level;
|
|
log->ubuf = log_ubuf;
|
|
log->len_total = log_size;
|
|
|
|
/* log attributes have to be sane */
|
|
if (log->len_total < 128 || log->len_total > UINT_MAX >> 8 ||
|
|
!log->level || !log->ubuf) {
|
|
err = -EINVAL;
|
|
goto errout;
|
|
}
|
|
}
|
|
|
|
btf = kzalloc(sizeof(*btf), GFP_KERNEL | __GFP_NOWARN);
|
|
if (!btf) {
|
|
err = -ENOMEM;
|
|
goto errout;
|
|
}
|
|
env->btf = btf;
|
|
|
|
data = kvmalloc(btf_data_size, GFP_KERNEL | __GFP_NOWARN);
|
|
if (!data) {
|
|
err = -ENOMEM;
|
|
goto errout;
|
|
}
|
|
|
|
btf->data = data;
|
|
btf->data_size = btf_data_size;
|
|
|
|
if (copy_from_user(data, btf_data, btf_data_size)) {
|
|
err = -EFAULT;
|
|
goto errout;
|
|
}
|
|
|
|
err = btf_parse_hdr(env);
|
|
if (err)
|
|
goto errout;
|
|
|
|
btf->nohdr_data = btf->data + btf->hdr.hdr_len;
|
|
|
|
err = btf_parse_str_sec(env);
|
|
if (err)
|
|
goto errout;
|
|
|
|
err = btf_parse_type_sec(env);
|
|
if (err)
|
|
goto errout;
|
|
|
|
if (log->level && bpf_verifier_log_full(log)) {
|
|
err = -ENOSPC;
|
|
goto errout;
|
|
}
|
|
|
|
btf_verifier_env_free(env);
|
|
refcount_set(&btf->refcnt, 1);
|
|
return btf;
|
|
|
|
errout:
|
|
btf_verifier_env_free(env);
|
|
if (btf)
|
|
btf_free(btf);
|
|
return ERR_PTR(err);
|
|
}
|
|
|
|
void btf_type_seq_show(const struct btf *btf, u32 type_id, void *obj,
|
|
struct seq_file *m)
|
|
{
|
|
const struct btf_type *t = btf_type_by_id(btf, type_id);
|
|
|
|
btf_type_ops(t)->seq_show(btf, t, type_id, obj, 0, m);
|
|
}
|
|
|
|
#ifdef CONFIG_PROC_FS
|
|
static void bpf_btf_show_fdinfo(struct seq_file *m, struct file *filp)
|
|
{
|
|
const struct btf *btf = filp->private_data;
|
|
|
|
seq_printf(m, "btf_id:\t%u\n", btf->id);
|
|
}
|
|
#endif
|
|
|
|
static int btf_release(struct inode *inode, struct file *filp)
|
|
{
|
|
btf_put(filp->private_data);
|
|
return 0;
|
|
}
|
|
|
|
const struct file_operations btf_fops = {
|
|
#ifdef CONFIG_PROC_FS
|
|
.show_fdinfo = bpf_btf_show_fdinfo,
|
|
#endif
|
|
.release = btf_release,
|
|
};
|
|
|
|
static int __btf_new_fd(struct btf *btf)
|
|
{
|
|
return anon_inode_getfd("btf", &btf_fops, btf, O_RDONLY | O_CLOEXEC);
|
|
}
|
|
|
|
int btf_new_fd(const union bpf_attr *attr)
|
|
{
|
|
struct btf *btf;
|
|
int ret;
|
|
|
|
btf = btf_parse(u64_to_user_ptr(attr->btf),
|
|
attr->btf_size, attr->btf_log_level,
|
|
u64_to_user_ptr(attr->btf_log_buf),
|
|
attr->btf_log_size);
|
|
if (IS_ERR(btf))
|
|
return PTR_ERR(btf);
|
|
|
|
ret = btf_alloc_id(btf);
|
|
if (ret) {
|
|
btf_free(btf);
|
|
return ret;
|
|
}
|
|
|
|
/*
|
|
* The BTF ID is published to the userspace.
|
|
* All BTF free must go through call_rcu() from
|
|
* now on (i.e. free by calling btf_put()).
|
|
*/
|
|
|
|
ret = __btf_new_fd(btf);
|
|
if (ret < 0)
|
|
btf_put(btf);
|
|
|
|
return ret;
|
|
}
|
|
|
|
struct btf *btf_get_by_fd(int fd)
|
|
{
|
|
struct btf *btf;
|
|
struct fd f;
|
|
|
|
f = fdget(fd);
|
|
|
|
if (!f.file)
|
|
return ERR_PTR(-EBADF);
|
|
|
|
if (f.file->f_op != &btf_fops) {
|
|
fdput(f);
|
|
return ERR_PTR(-EINVAL);
|
|
}
|
|
|
|
btf = f.file->private_data;
|
|
refcount_inc(&btf->refcnt);
|
|
fdput(f);
|
|
|
|
return btf;
|
|
}
|
|
|
|
int btf_get_info_by_fd(const struct btf *btf,
|
|
const union bpf_attr *attr,
|
|
union bpf_attr __user *uattr)
|
|
{
|
|
struct bpf_btf_info __user *uinfo;
|
|
struct bpf_btf_info info = {};
|
|
u32 info_copy, btf_copy;
|
|
void __user *ubtf;
|
|
u32 uinfo_len;
|
|
|
|
uinfo = u64_to_user_ptr(attr->info.info);
|
|
uinfo_len = attr->info.info_len;
|
|
|
|
info_copy = min_t(u32, uinfo_len, sizeof(info));
|
|
if (copy_from_user(&info, uinfo, info_copy))
|
|
return -EFAULT;
|
|
|
|
info.id = btf->id;
|
|
ubtf = u64_to_user_ptr(info.btf);
|
|
btf_copy = min_t(u32, btf->data_size, info.btf_size);
|
|
if (copy_to_user(ubtf, btf->data, btf_copy))
|
|
return -EFAULT;
|
|
info.btf_size = btf->data_size;
|
|
|
|
if (copy_to_user(uinfo, &info, info_copy) ||
|
|
put_user(info_copy, &uattr->info.info_len))
|
|
return -EFAULT;
|
|
|
|
return 0;
|
|
}
|
|
|
|
int btf_get_fd_by_id(u32 id)
|
|
{
|
|
struct btf *btf;
|
|
int fd;
|
|
|
|
rcu_read_lock();
|
|
btf = idr_find(&btf_idr, id);
|
|
if (!btf || !refcount_inc_not_zero(&btf->refcnt))
|
|
btf = ERR_PTR(-ENOENT);
|
|
rcu_read_unlock();
|
|
|
|
if (IS_ERR(btf))
|
|
return PTR_ERR(btf);
|
|
|
|
fd = __btf_new_fd(btf);
|
|
if (fd < 0)
|
|
btf_put(btf);
|
|
|
|
return fd;
|
|
}
|
|
|
|
u32 btf_id(const struct btf *btf)
|
|
{
|
|
return btf->id;
|
|
}
|