x86/insn: Add an insn_decode() API
Users of the instruction decoder should use this to decode instruction bytes. For that, have insn*() helpers return an int value to denote success/failure. When there's an error fetching the next insn byte and the insn falls short, return -ENODATA to denote that. While at it, make insn_get_opcode() more stricter as to whether what has seen so far is a valid insn and if not. Copy linux/kconfig.h for the tools-version of the decoder so that it can use IS_ENABLED(). Also, cast the INSN_MODE_KERN dummy define value to (enum insn_mode) for tools use of the decoder because perf tool builds with -Werror and errors out with -Werror=sign-compare otherwise. Signed-off-by: Borislav Petkov <bp@suse.de> Acked-by: Masami Hiramatsu <mhiramat@kernel.org> Link: https://lkml.kernel.org/r/20210304174237.31945-5-bp@alien8.de
This commit is contained in:
Родитель
d30c7b820b
Коммит
93281c4a96
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@ -132,13 +132,23 @@ struct insn {
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#define X86_VEX_M_MAX 0x1f /* VEX3.M Maximum value */
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extern void insn_init(struct insn *insn, const void *kaddr, int buf_len, int x86_64);
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extern void insn_get_prefixes(struct insn *insn);
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extern void insn_get_opcode(struct insn *insn);
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extern void insn_get_modrm(struct insn *insn);
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extern void insn_get_sib(struct insn *insn);
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extern void insn_get_displacement(struct insn *insn);
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extern void insn_get_immediate(struct insn *insn);
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extern void insn_get_length(struct insn *insn);
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extern int insn_get_prefixes(struct insn *insn);
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extern int insn_get_opcode(struct insn *insn);
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extern int insn_get_modrm(struct insn *insn);
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extern int insn_get_sib(struct insn *insn);
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extern int insn_get_displacement(struct insn *insn);
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extern int insn_get_immediate(struct insn *insn);
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extern int insn_get_length(struct insn *insn);
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enum insn_mode {
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INSN_MODE_32,
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INSN_MODE_64,
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/* Mode is determined by the current kernel build. */
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INSN_MODE_KERN,
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INSN_NUM_MODES,
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};
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extern int insn_decode(struct insn *insn, const void *kaddr, int buf_len, enum insn_mode m);
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/* Attribute will be determined after getting ModRM (for opcode groups) */
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static inline void insn_get_attribute(struct insn *insn)
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@ -14,6 +14,9 @@
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#include <asm/inat.h> /*__ignore_sync_check__ */
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#include <asm/insn.h> /* __ignore_sync_check__ */
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#include <linux/errno.h>
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#include <linux/kconfig.h>
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#include <asm/emulate_prefix.h> /* __ignore_sync_check__ */
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#define leXX_to_cpu(t, r) \
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@ -112,8 +115,12 @@ static void insn_get_emulate_prefix(struct insn *insn)
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* Populates the @insn->prefixes bitmap, and updates @insn->next_byte
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* to point to the (first) opcode. No effect if @insn->prefixes.got
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* is already set.
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*
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* * Returns:
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* 0: on success
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* < 0: on error
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*/
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void insn_get_prefixes(struct insn *insn)
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int insn_get_prefixes(struct insn *insn)
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{
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struct insn_field *prefixes = &insn->prefixes;
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insn_attr_t attr;
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@ -121,7 +128,7 @@ void insn_get_prefixes(struct insn *insn)
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int i, nb;
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if (prefixes->got)
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return;
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return 0;
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insn_get_emulate_prefix(insn);
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@ -231,8 +238,10 @@ vex_end:
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prefixes->got = 1;
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return 0;
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err_out:
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return;
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return -ENODATA;
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}
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/**
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@ -244,16 +253,25 @@ err_out:
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* If necessary, first collects any preceding (prefix) bytes.
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* Sets @insn->opcode.value = opcode1. No effect if @insn->opcode.got
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* is already 1.
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*
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* Returns:
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* 0: on success
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* < 0: on error
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*/
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void insn_get_opcode(struct insn *insn)
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int insn_get_opcode(struct insn *insn)
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{
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struct insn_field *opcode = &insn->opcode;
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int pfx_id, ret;
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insn_byte_t op;
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int pfx_id;
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if (opcode->got)
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return;
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if (!insn->prefixes.got)
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insn_get_prefixes(insn);
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return 0;
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if (!insn->prefixes.got) {
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ret = insn_get_prefixes(insn);
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if (ret)
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return ret;
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}
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/* Get first opcode */
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op = get_next(insn_byte_t, insn);
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@ -268,9 +286,13 @@ void insn_get_opcode(struct insn *insn)
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insn->attr = inat_get_avx_attribute(op, m, p);
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if ((inat_must_evex(insn->attr) && !insn_is_evex(insn)) ||
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(!inat_accept_vex(insn->attr) &&
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!inat_is_group(insn->attr)))
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insn->attr = 0; /* This instruction is bad */
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goto end; /* VEX has only 1 byte for opcode */
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!inat_is_group(insn->attr))) {
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/* This instruction is bad */
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insn->attr = 0;
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return -EINVAL;
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}
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/* VEX has only 1 byte for opcode */
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goto end;
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}
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insn->attr = inat_get_opcode_attribute(op);
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@ -281,13 +303,18 @@ void insn_get_opcode(struct insn *insn)
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pfx_id = insn_last_prefix_id(insn);
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insn->attr = inat_get_escape_attribute(op, pfx_id, insn->attr);
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}
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if (inat_must_vex(insn->attr))
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insn->attr = 0; /* This instruction is bad */
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if (inat_must_vex(insn->attr)) {
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/* This instruction is bad */
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insn->attr = 0;
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return -EINVAL;
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}
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end:
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opcode->got = 1;
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return 0;
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err_out:
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return;
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return -ENODATA;
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}
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/**
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@ -297,15 +324,25 @@ err_out:
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* Populates @insn->modrm and updates @insn->next_byte to point past the
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* ModRM byte, if any. If necessary, first collects the preceding bytes
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* (prefixes and opcode(s)). No effect if @insn->modrm.got is already 1.
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*
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* Returns:
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* 0: on success
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* < 0: on error
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*/
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void insn_get_modrm(struct insn *insn)
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int insn_get_modrm(struct insn *insn)
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{
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struct insn_field *modrm = &insn->modrm;
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insn_byte_t pfx_id, mod;
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int ret;
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if (modrm->got)
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return;
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if (!insn->opcode.got)
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insn_get_opcode(insn);
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return 0;
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if (!insn->opcode.got) {
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ret = insn_get_opcode(insn);
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if (ret)
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return ret;
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}
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if (inat_has_modrm(insn->attr)) {
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mod = get_next(insn_byte_t, insn);
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@ -314,17 +351,22 @@ void insn_get_modrm(struct insn *insn)
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pfx_id = insn_last_prefix_id(insn);
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insn->attr = inat_get_group_attribute(mod, pfx_id,
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insn->attr);
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if (insn_is_avx(insn) && !inat_accept_vex(insn->attr))
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insn->attr = 0; /* This is bad */
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if (insn_is_avx(insn) && !inat_accept_vex(insn->attr)) {
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/* Bad insn */
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insn->attr = 0;
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return -EINVAL;
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}
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}
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}
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if (insn->x86_64 && inat_is_force64(insn->attr))
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insn->opnd_bytes = 8;
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modrm->got = 1;
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return 0;
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err_out:
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return;
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return -ENODATA;
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}
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@ -338,11 +380,16 @@ err_out:
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int insn_rip_relative(struct insn *insn)
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{
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struct insn_field *modrm = &insn->modrm;
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int ret;
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if (!insn->x86_64)
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return 0;
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if (!modrm->got)
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insn_get_modrm(insn);
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if (!modrm->got) {
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ret = insn_get_modrm(insn);
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if (ret)
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return 0;
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}
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/*
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* For rip-relative instructions, the mod field (top 2 bits)
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* is zero and the r/m field (bottom 3 bits) is 0x5.
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@ -356,15 +403,25 @@ int insn_rip_relative(struct insn *insn)
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*
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* If necessary, first collects the instruction up to and including the
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* ModRM byte.
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*
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* Returns:
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* 0: if decoding succeeded
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* < 0: otherwise.
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*/
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void insn_get_sib(struct insn *insn)
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int insn_get_sib(struct insn *insn)
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{
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insn_byte_t modrm;
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int ret;
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if (insn->sib.got)
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return;
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if (!insn->modrm.got)
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insn_get_modrm(insn);
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return 0;
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if (!insn->modrm.got) {
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ret = insn_get_modrm(insn);
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if (ret)
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return ret;
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}
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if (insn->modrm.nbytes) {
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modrm = insn->modrm.bytes[0];
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if (insn->addr_bytes != 2 &&
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@ -375,8 +432,10 @@ void insn_get_sib(struct insn *insn)
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}
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insn->sib.got = 1;
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return 0;
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err_out:
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return;
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return -ENODATA;
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}
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@ -387,15 +446,25 @@ err_out:
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* If necessary, first collects the instruction up to and including the
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* SIB byte.
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* Displacement value is sign-expanded.
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*
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* * Returns:
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* 0: if decoding succeeded
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* < 0: otherwise.
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*/
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void insn_get_displacement(struct insn *insn)
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int insn_get_displacement(struct insn *insn)
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{
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insn_byte_t mod, rm, base;
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int ret;
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if (insn->displacement.got)
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return;
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if (!insn->sib.got)
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insn_get_sib(insn);
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return 0;
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if (!insn->sib.got) {
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ret = insn_get_sib(insn);
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if (ret)
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return ret;
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}
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if (insn->modrm.nbytes) {
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/*
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* Interpreting the modrm byte:
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@ -437,9 +506,10 @@ void insn_get_displacement(struct insn *insn)
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}
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out:
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insn->displacement.got = 1;
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return 0;
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err_out:
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return;
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return -ENODATA;
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}
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/* Decode moffset16/32/64. Return 0 if failed */
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@ -538,20 +608,30 @@ err_out:
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}
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/**
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* insn_get_immediate() - Get the immediates of instruction
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* insn_get_immediate() - Get the immediate in an instruction
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* @insn: &struct insn containing instruction
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*
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* If necessary, first collects the instruction up to and including the
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* displacement bytes.
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* Basically, most of immediates are sign-expanded. Unsigned-value can be
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* get by bit masking with ((1 << (nbytes * 8)) - 1)
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* computed by bit masking with ((1 << (nbytes * 8)) - 1)
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*
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* Returns:
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* 0: on success
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* < 0: on error
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*/
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void insn_get_immediate(struct insn *insn)
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int insn_get_immediate(struct insn *insn)
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{
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int ret;
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if (insn->immediate.got)
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return;
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if (!insn->displacement.got)
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insn_get_displacement(insn);
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return 0;
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if (!insn->displacement.got) {
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ret = insn_get_displacement(insn);
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if (ret)
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return ret;
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}
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if (inat_has_moffset(insn->attr)) {
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if (!__get_moffset(insn))
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@ -598,9 +678,10 @@ void insn_get_immediate(struct insn *insn)
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}
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done:
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insn->immediate.got = 1;
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return 0;
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err_out:
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return;
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return -ENODATA;
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}
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/**
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@ -609,13 +690,58 @@ err_out:
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*
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* If necessary, first collects the instruction up to and including the
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* immediates bytes.
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*/
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void insn_get_length(struct insn *insn)
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*
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* Returns:
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* - 0 on success
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* - < 0 on error
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*/
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int insn_get_length(struct insn *insn)
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{
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int ret;
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if (insn->length)
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return;
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if (!insn->immediate.got)
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insn_get_immediate(insn);
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return 0;
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if (!insn->immediate.got) {
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ret = insn_get_immediate(insn);
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if (ret)
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return ret;
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}
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insn->length = (unsigned char)((unsigned long)insn->next_byte
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- (unsigned long)insn->kaddr);
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return 0;
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}
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/**
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* insn_decode() - Decode an x86 instruction
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* @insn: &struct insn to be initialized
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* @kaddr: address (in kernel memory) of instruction (or copy thereof)
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* @buf_len: length of the insn buffer at @kaddr
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* @m: insn mode, see enum insn_mode
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*
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* Returns:
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* 0: if decoding succeeded
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* < 0: otherwise.
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*/
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int insn_decode(struct insn *insn, const void *kaddr, int buf_len, enum insn_mode m)
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{
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int ret;
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/* #define INSN_MODE_KERN -1 __ignore_sync_check__ mode is only valid in the kernel */
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if (m == INSN_MODE_KERN)
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insn_init(insn, kaddr, buf_len, IS_ENABLED(CONFIG_X86_64));
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else
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insn_init(insn, kaddr, buf_len, m == INSN_MODE_64);
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ret = insn_get_length(insn);
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if (ret)
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return ret;
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if (insn_complete(insn))
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return 0;
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return -EINVAL;
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}
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|
|
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@ -132,13 +132,23 @@ struct insn {
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#define X86_VEX_M_MAX 0x1f /* VEX3.M Maximum value */
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extern void insn_init(struct insn *insn, const void *kaddr, int buf_len, int x86_64);
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extern void insn_get_prefixes(struct insn *insn);
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extern void insn_get_opcode(struct insn *insn);
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extern void insn_get_modrm(struct insn *insn);
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extern void insn_get_sib(struct insn *insn);
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extern void insn_get_displacement(struct insn *insn);
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extern void insn_get_immediate(struct insn *insn);
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extern void insn_get_length(struct insn *insn);
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extern int insn_get_prefixes(struct insn *insn);
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extern int insn_get_opcode(struct insn *insn);
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extern int insn_get_modrm(struct insn *insn);
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extern int insn_get_sib(struct insn *insn);
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extern int insn_get_displacement(struct insn *insn);
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extern int insn_get_immediate(struct insn *insn);
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extern int insn_get_length(struct insn *insn);
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enum insn_mode {
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INSN_MODE_32,
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INSN_MODE_64,
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/* Mode is determined by the current kernel build. */
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INSN_MODE_KERN,
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INSN_NUM_MODES,
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};
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extern int insn_decode(struct insn *insn, const void *kaddr, int buf_len, enum insn_mode m);
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/* Attribute will be determined after getting ModRM (for opcode groups) */
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static inline void insn_get_attribute(struct insn *insn)
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|
|
|
@ -11,10 +11,13 @@
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#else
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#include <string.h>
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#endif
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#include "../include/asm/inat.h" /* __ignore_sync_check__ */
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#include "../include/asm/insn.h" /* __ignore_sync_check__ */
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#include <asm/inat.h> /*__ignore_sync_check__ */
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#include <asm/insn.h> /* __ignore_sync_check__ */
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#include "../include/asm/emulate_prefix.h" /* __ignore_sync_check__ */
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||||
#include <linux/errno.h>
|
||||
#include <linux/kconfig.h>
|
||||
|
||||
#include <asm/emulate_prefix.h> /* __ignore_sync_check__ */
|
||||
|
||||
#define leXX_to_cpu(t, r) \
|
||||
({ \
|
||||
|
@ -112,8 +115,12 @@ static void insn_get_emulate_prefix(struct insn *insn)
|
|||
* Populates the @insn->prefixes bitmap, and updates @insn->next_byte
|
||||
* to point to the (first) opcode. No effect if @insn->prefixes.got
|
||||
* is already set.
|
||||
*
|
||||
* * Returns:
|
||||
* 0: on success
|
||||
* < 0: on error
|
||||
*/
|
||||
void insn_get_prefixes(struct insn *insn)
|
||||
int insn_get_prefixes(struct insn *insn)
|
||||
{
|
||||
struct insn_field *prefixes = &insn->prefixes;
|
||||
insn_attr_t attr;
|
||||
|
@ -121,7 +128,7 @@ void insn_get_prefixes(struct insn *insn)
|
|||
int i, nb;
|
||||
|
||||
if (prefixes->got)
|
||||
return;
|
||||
return 0;
|
||||
|
||||
insn_get_emulate_prefix(insn);
|
||||
|
||||
|
@ -231,8 +238,10 @@ vex_end:
|
|||
|
||||
prefixes->got = 1;
|
||||
|
||||
return 0;
|
||||
|
||||
err_out:
|
||||
return;
|
||||
return -ENODATA;
|
||||
}
|
||||
|
||||
/**
|
||||
|
@ -244,16 +253,25 @@ err_out:
|
|||
* If necessary, first collects any preceding (prefix) bytes.
|
||||
* Sets @insn->opcode.value = opcode1. No effect if @insn->opcode.got
|
||||
* is already 1.
|
||||
*
|
||||
* Returns:
|
||||
* 0: on success
|
||||
* < 0: on error
|
||||
*/
|
||||
void insn_get_opcode(struct insn *insn)
|
||||
int insn_get_opcode(struct insn *insn)
|
||||
{
|
||||
struct insn_field *opcode = &insn->opcode;
|
||||
int pfx_id, ret;
|
||||
insn_byte_t op;
|
||||
int pfx_id;
|
||||
|
||||
if (opcode->got)
|
||||
return;
|
||||
if (!insn->prefixes.got)
|
||||
insn_get_prefixes(insn);
|
||||
return 0;
|
||||
|
||||
if (!insn->prefixes.got) {
|
||||
ret = insn_get_prefixes(insn);
|
||||
if (ret)
|
||||
return ret;
|
||||
}
|
||||
|
||||
/* Get first opcode */
|
||||
op = get_next(insn_byte_t, insn);
|
||||
|
@ -268,9 +286,13 @@ void insn_get_opcode(struct insn *insn)
|
|||
insn->attr = inat_get_avx_attribute(op, m, p);
|
||||
if ((inat_must_evex(insn->attr) && !insn_is_evex(insn)) ||
|
||||
(!inat_accept_vex(insn->attr) &&
|
||||
!inat_is_group(insn->attr)))
|
||||
insn->attr = 0; /* This instruction is bad */
|
||||
goto end; /* VEX has only 1 byte for opcode */
|
||||
!inat_is_group(insn->attr))) {
|
||||
/* This instruction is bad */
|
||||
insn->attr = 0;
|
||||
return -EINVAL;
|
||||
}
|
||||
/* VEX has only 1 byte for opcode */
|
||||
goto end;
|
||||
}
|
||||
|
||||
insn->attr = inat_get_opcode_attribute(op);
|
||||
|
@ -281,13 +303,18 @@ void insn_get_opcode(struct insn *insn)
|
|||
pfx_id = insn_last_prefix_id(insn);
|
||||
insn->attr = inat_get_escape_attribute(op, pfx_id, insn->attr);
|
||||
}
|
||||
if (inat_must_vex(insn->attr))
|
||||
insn->attr = 0; /* This instruction is bad */
|
||||
|
||||
if (inat_must_vex(insn->attr)) {
|
||||
/* This instruction is bad */
|
||||
insn->attr = 0;
|
||||
return -EINVAL;
|
||||
}
|
||||
end:
|
||||
opcode->got = 1;
|
||||
return 0;
|
||||
|
||||
err_out:
|
||||
return;
|
||||
return -ENODATA;
|
||||
}
|
||||
|
||||
/**
|
||||
|
@ -297,15 +324,25 @@ err_out:
|
|||
* Populates @insn->modrm and updates @insn->next_byte to point past the
|
||||
* ModRM byte, if any. If necessary, first collects the preceding bytes
|
||||
* (prefixes and opcode(s)). No effect if @insn->modrm.got is already 1.
|
||||
*
|
||||
* Returns:
|
||||
* 0: on success
|
||||
* < 0: on error
|
||||
*/
|
||||
void insn_get_modrm(struct insn *insn)
|
||||
int insn_get_modrm(struct insn *insn)
|
||||
{
|
||||
struct insn_field *modrm = &insn->modrm;
|
||||
insn_byte_t pfx_id, mod;
|
||||
int ret;
|
||||
|
||||
if (modrm->got)
|
||||
return;
|
||||
if (!insn->opcode.got)
|
||||
insn_get_opcode(insn);
|
||||
return 0;
|
||||
|
||||
if (!insn->opcode.got) {
|
||||
ret = insn_get_opcode(insn);
|
||||
if (ret)
|
||||
return ret;
|
||||
}
|
||||
|
||||
if (inat_has_modrm(insn->attr)) {
|
||||
mod = get_next(insn_byte_t, insn);
|
||||
|
@ -314,17 +351,22 @@ void insn_get_modrm(struct insn *insn)
|
|||
pfx_id = insn_last_prefix_id(insn);
|
||||
insn->attr = inat_get_group_attribute(mod, pfx_id,
|
||||
insn->attr);
|
||||
if (insn_is_avx(insn) && !inat_accept_vex(insn->attr))
|
||||
insn->attr = 0; /* This is bad */
|
||||
if (insn_is_avx(insn) && !inat_accept_vex(insn->attr)) {
|
||||
/* Bad insn */
|
||||
insn->attr = 0;
|
||||
return -EINVAL;
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
if (insn->x86_64 && inat_is_force64(insn->attr))
|
||||
insn->opnd_bytes = 8;
|
||||
|
||||
modrm->got = 1;
|
||||
return 0;
|
||||
|
||||
err_out:
|
||||
return;
|
||||
return -ENODATA;
|
||||
}
|
||||
|
||||
|
||||
|
@ -338,11 +380,16 @@ err_out:
|
|||
int insn_rip_relative(struct insn *insn)
|
||||
{
|
||||
struct insn_field *modrm = &insn->modrm;
|
||||
int ret;
|
||||
|
||||
if (!insn->x86_64)
|
||||
return 0;
|
||||
if (!modrm->got)
|
||||
insn_get_modrm(insn);
|
||||
|
||||
if (!modrm->got) {
|
||||
ret = insn_get_modrm(insn);
|
||||
if (ret)
|
||||
return 0;
|
||||
}
|
||||
/*
|
||||
* For rip-relative instructions, the mod field (top 2 bits)
|
||||
* is zero and the r/m field (bottom 3 bits) is 0x5.
|
||||
|
@ -356,15 +403,25 @@ int insn_rip_relative(struct insn *insn)
|
|||
*
|
||||
* If necessary, first collects the instruction up to and including the
|
||||
* ModRM byte.
|
||||
*
|
||||
* Returns:
|
||||
* 0: if decoding succeeded
|
||||
* < 0: otherwise.
|
||||
*/
|
||||
void insn_get_sib(struct insn *insn)
|
||||
int insn_get_sib(struct insn *insn)
|
||||
{
|
||||
insn_byte_t modrm;
|
||||
int ret;
|
||||
|
||||
if (insn->sib.got)
|
||||
return;
|
||||
if (!insn->modrm.got)
|
||||
insn_get_modrm(insn);
|
||||
return 0;
|
||||
|
||||
if (!insn->modrm.got) {
|
||||
ret = insn_get_modrm(insn);
|
||||
if (ret)
|
||||
return ret;
|
||||
}
|
||||
|
||||
if (insn->modrm.nbytes) {
|
||||
modrm = insn->modrm.bytes[0];
|
||||
if (insn->addr_bytes != 2 &&
|
||||
|
@ -375,8 +432,10 @@ void insn_get_sib(struct insn *insn)
|
|||
}
|
||||
insn->sib.got = 1;
|
||||
|
||||
return 0;
|
||||
|
||||
err_out:
|
||||
return;
|
||||
return -ENODATA;
|
||||
}
|
||||
|
||||
|
||||
|
@ -387,15 +446,25 @@ err_out:
|
|||
* If necessary, first collects the instruction up to and including the
|
||||
* SIB byte.
|
||||
* Displacement value is sign-expanded.
|
||||
*
|
||||
* * Returns:
|
||||
* 0: if decoding succeeded
|
||||
* < 0: otherwise.
|
||||
*/
|
||||
void insn_get_displacement(struct insn *insn)
|
||||
int insn_get_displacement(struct insn *insn)
|
||||
{
|
||||
insn_byte_t mod, rm, base;
|
||||
int ret;
|
||||
|
||||
if (insn->displacement.got)
|
||||
return;
|
||||
if (!insn->sib.got)
|
||||
insn_get_sib(insn);
|
||||
return 0;
|
||||
|
||||
if (!insn->sib.got) {
|
||||
ret = insn_get_sib(insn);
|
||||
if (ret)
|
||||
return ret;
|
||||
}
|
||||
|
||||
if (insn->modrm.nbytes) {
|
||||
/*
|
||||
* Interpreting the modrm byte:
|
||||
|
@ -437,9 +506,10 @@ void insn_get_displacement(struct insn *insn)
|
|||
}
|
||||
out:
|
||||
insn->displacement.got = 1;
|
||||
return 0;
|
||||
|
||||
err_out:
|
||||
return;
|
||||
return -ENODATA;
|
||||
}
|
||||
|
||||
/* Decode moffset16/32/64. Return 0 if failed */
|
||||
|
@ -538,20 +608,30 @@ err_out:
|
|||
}
|
||||
|
||||
/**
|
||||
* insn_get_immediate() - Get the immediates of instruction
|
||||
* insn_get_immediate() - Get the immediate in an instruction
|
||||
* @insn: &struct insn containing instruction
|
||||
*
|
||||
* If necessary, first collects the instruction up to and including the
|
||||
* displacement bytes.
|
||||
* Basically, most of immediates are sign-expanded. Unsigned-value can be
|
||||
* get by bit masking with ((1 << (nbytes * 8)) - 1)
|
||||
* computed by bit masking with ((1 << (nbytes * 8)) - 1)
|
||||
*
|
||||
* Returns:
|
||||
* 0: on success
|
||||
* < 0: on error
|
||||
*/
|
||||
void insn_get_immediate(struct insn *insn)
|
||||
int insn_get_immediate(struct insn *insn)
|
||||
{
|
||||
int ret;
|
||||
|
||||
if (insn->immediate.got)
|
||||
return;
|
||||
if (!insn->displacement.got)
|
||||
insn_get_displacement(insn);
|
||||
return 0;
|
||||
|
||||
if (!insn->displacement.got) {
|
||||
ret = insn_get_displacement(insn);
|
||||
if (ret)
|
||||
return ret;
|
||||
}
|
||||
|
||||
if (inat_has_moffset(insn->attr)) {
|
||||
if (!__get_moffset(insn))
|
||||
|
@ -598,9 +678,10 @@ void insn_get_immediate(struct insn *insn)
|
|||
}
|
||||
done:
|
||||
insn->immediate.got = 1;
|
||||
return 0;
|
||||
|
||||
err_out:
|
||||
return;
|
||||
return -ENODATA;
|
||||
}
|
||||
|
||||
/**
|
||||
|
@ -609,13 +690,58 @@ err_out:
|
|||
*
|
||||
* If necessary, first collects the instruction up to and including the
|
||||
* immediates bytes.
|
||||
*/
|
||||
void insn_get_length(struct insn *insn)
|
||||
*
|
||||
* Returns:
|
||||
* - 0 on success
|
||||
* - < 0 on error
|
||||
*/
|
||||
int insn_get_length(struct insn *insn)
|
||||
{
|
||||
int ret;
|
||||
|
||||
if (insn->length)
|
||||
return;
|
||||
if (!insn->immediate.got)
|
||||
insn_get_immediate(insn);
|
||||
return 0;
|
||||
|
||||
if (!insn->immediate.got) {
|
||||
ret = insn_get_immediate(insn);
|
||||
if (ret)
|
||||
return ret;
|
||||
}
|
||||
|
||||
insn->length = (unsigned char)((unsigned long)insn->next_byte
|
||||
- (unsigned long)insn->kaddr);
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
/**
|
||||
* insn_decode() - Decode an x86 instruction
|
||||
* @insn: &struct insn to be initialized
|
||||
* @kaddr: address (in kernel memory) of instruction (or copy thereof)
|
||||
* @buf_len: length of the insn buffer at @kaddr
|
||||
* @m: insn mode, see enum insn_mode
|
||||
*
|
||||
* Returns:
|
||||
* 0: if decoding succeeded
|
||||
* < 0: otherwise.
|
||||
*/
|
||||
int insn_decode(struct insn *insn, const void *kaddr, int buf_len, enum insn_mode m)
|
||||
{
|
||||
int ret;
|
||||
|
||||
#define INSN_MODE_KERN (enum insn_mode)-1 /* __ignore_sync_check__ mode is only valid in the kernel */
|
||||
|
||||
if (m == INSN_MODE_KERN)
|
||||
insn_init(insn, kaddr, buf_len, IS_ENABLED(CONFIG_X86_64));
|
||||
else
|
||||
insn_init(insn, kaddr, buf_len, m == INSN_MODE_64);
|
||||
|
||||
ret = insn_get_length(insn);
|
||||
if (ret)
|
||||
return ret;
|
||||
|
||||
if (insn_complete(insn))
|
||||
return 0;
|
||||
|
||||
return -EINVAL;
|
||||
}
|
||||
|
|
|
@ -0,0 +1,73 @@
|
|||
/* SPDX-License-Identifier: GPL-2.0 */
|
||||
#ifndef _TOOLS_LINUX_KCONFIG_H
|
||||
#define _TOOLS_LINUX_KCONFIG_H
|
||||
|
||||
/* CONFIG_CC_VERSION_TEXT (Do not delete this comment. See help in Kconfig) */
|
||||
|
||||
#ifdef CONFIG_CPU_BIG_ENDIAN
|
||||
#define __BIG_ENDIAN 4321
|
||||
#else
|
||||
#define __LITTLE_ENDIAN 1234
|
||||
#endif
|
||||
|
||||
#define __ARG_PLACEHOLDER_1 0,
|
||||
#define __take_second_arg(__ignored, val, ...) val
|
||||
|
||||
/*
|
||||
* The use of "&&" / "||" is limited in certain expressions.
|
||||
* The following enable to calculate "and" / "or" with macro expansion only.
|
||||
*/
|
||||
#define __and(x, y) ___and(x, y)
|
||||
#define ___and(x, y) ____and(__ARG_PLACEHOLDER_##x, y)
|
||||
#define ____and(arg1_or_junk, y) __take_second_arg(arg1_or_junk y, 0)
|
||||
|
||||
#define __or(x, y) ___or(x, y)
|
||||
#define ___or(x, y) ____or(__ARG_PLACEHOLDER_##x, y)
|
||||
#define ____or(arg1_or_junk, y) __take_second_arg(arg1_or_junk 1, y)
|
||||
|
||||
/*
|
||||
* Helper macros to use CONFIG_ options in C/CPP expressions. Note that
|
||||
* these only work with boolean and tristate options.
|
||||
*/
|
||||
|
||||
/*
|
||||
* Getting something that works in C and CPP for an arg that may or may
|
||||
* not be defined is tricky. Here, if we have "#define CONFIG_BOOGER 1"
|
||||
* we match on the placeholder define, insert the "0," for arg1 and generate
|
||||
* the triplet (0, 1, 0). Then the last step cherry picks the 2nd arg (a one).
|
||||
* When CONFIG_BOOGER is not defined, we generate a (... 1, 0) pair, and when
|
||||
* the last step cherry picks the 2nd arg, we get a zero.
|
||||
*/
|
||||
#define __is_defined(x) ___is_defined(x)
|
||||
#define ___is_defined(val) ____is_defined(__ARG_PLACEHOLDER_##val)
|
||||
#define ____is_defined(arg1_or_junk) __take_second_arg(arg1_or_junk 1, 0)
|
||||
|
||||
/*
|
||||
* IS_BUILTIN(CONFIG_FOO) evaluates to 1 if CONFIG_FOO is set to 'y', 0
|
||||
* otherwise. For boolean options, this is equivalent to
|
||||
* IS_ENABLED(CONFIG_FOO).
|
||||
*/
|
||||
#define IS_BUILTIN(option) __is_defined(option)
|
||||
|
||||
/*
|
||||
* IS_MODULE(CONFIG_FOO) evaluates to 1 if CONFIG_FOO is set to 'm', 0
|
||||
* otherwise.
|
||||
*/
|
||||
#define IS_MODULE(option) __is_defined(option##_MODULE)
|
||||
|
||||
/*
|
||||
* IS_REACHABLE(CONFIG_FOO) evaluates to 1 if the currently compiled
|
||||
* code can call a function defined in code compiled based on CONFIG_FOO.
|
||||
* This is similar to IS_ENABLED(), but returns false when invoked from
|
||||
* built-in code when CONFIG_FOO is set to 'm'.
|
||||
*/
|
||||
#define IS_REACHABLE(option) __or(IS_BUILTIN(option), \
|
||||
__and(IS_MODULE(option), __is_defined(MODULE)))
|
||||
|
||||
/*
|
||||
* IS_ENABLED(CONFIG_FOO) evaluates to 1 if CONFIG_FOO is set to 'y' or 'm',
|
||||
* 0 otherwise.
|
||||
*/
|
||||
#define IS_ENABLED(option) __or(IS_BUILTIN(option), IS_MODULE(option))
|
||||
|
||||
#endif /* _TOOLS_LINUX_KCONFIG_H */
|
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