Current MIPS64r6 toolchains aren't able to generate efficient
DMULU/DMUHU based code for the C implementation of umul_ppmm(), which
performs an unsigned 64 x 64 bit multiply and returns the upper and
lower 64-bit halves of the 128-bit result. Instead it widens the 64-bit
inputs to 128-bits and emits a __multi3 intrinsic call to perform a 128
x 128 multiply. This is both inefficient, and it results in a link error
since we don't include __multi3 in MIPS linux.
For example commit 90a53e4432 ("cfg80211: implement regdb signature
checking") merged in v4.15-rc1 recently broke the 64r6_defconfig and
64r6el_defconfig builds by indirectly selecting MPILIB. The same build
errors can be reproduced on older kernels by enabling e.g. CRYPTO_RSA:
lib/mpi/generic_mpih-mul1.o: In function `mpihelp_mul_1':
lib/mpi/generic_mpih-mul1.c:50: undefined reference to `__multi3'
lib/mpi/generic_mpih-mul2.o: In function `mpihelp_addmul_1':
lib/mpi/generic_mpih-mul2.c:49: undefined reference to `__multi3'
lib/mpi/generic_mpih-mul3.o: In function `mpihelp_submul_1':
lib/mpi/generic_mpih-mul3.c:49: undefined reference to `__multi3'
lib/mpi/mpih-div.o In function `mpihelp_divrem':
lib/mpi/mpih-div.c:205: undefined reference to `__multi3'
lib/mpi/mpih-div.c:142: undefined reference to `__multi3'
Therefore add an efficient MIPS64r6 implementation of umul_ppmm() using
inline assembly and the DMULU/DMUHU instructions, to prevent __multi3
calls being emitted.
Fixes: 7fd08ca58a ("MIPS: Add build support for the MIPS R6 ISA")
Signed-off-by: James Hogan <jhogan@kernel.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: linux-mips@linux-mips.org
Cc: linux-crypto@vger.kernel.org
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Pull crypto updates from Herbert Xu:
"Here is the crypto update for 4.15:
API:
- Disambiguate EBUSY when queueing crypto request by adding ENOSPC.
This change touches code outside the crypto API.
- Reset settings when empty string is written to rng_current.
Algorithms:
- Add OSCCA SM3 secure hash.
Drivers:
- Remove old mv_cesa driver (replaced by marvell/cesa).
- Enable rfc3686/ecb/cfb/ofb AES in crypto4xx.
- Add ccm/gcm AES in crypto4xx.
- Add support for BCM7278 in iproc-rng200.
- Add hash support on Exynos in s5p-sss.
- Fix fallback-induced error in vmx.
- Fix output IV in atmel-aes.
- Fix empty GCM hash in mediatek.
Others:
- Fix DoS potential in lib/mpi.
- Fix potential out-of-order issues with padata"
* 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6: (162 commits)
lib/mpi: call cond_resched() from mpi_powm() loop
crypto: stm32/hash - Fix return issue on update
crypto: dh - Remove pointless checks for NULL 'p' and 'g'
crypto: qat - Clean up error handling in qat_dh_set_secret()
crypto: dh - Don't permit 'key' or 'g' size longer than 'p'
crypto: dh - Don't permit 'p' to be 0
crypto: dh - Fix double free of ctx->p
hwrng: iproc-rng200 - Add support for BCM7278
dt-bindings: rng: Document BCM7278 RNG200 compatible
crypto: chcr - Replace _manual_ swap with swap macro
crypto: marvell - Add a NULL entry at the end of mv_cesa_plat_id_table[]
hwrng: virtio - Virtio RNG devices need to be re-registered after suspend/resume
crypto: atmel - remove empty functions
crypto: ecdh - remove empty exit()
MAINTAINERS: update maintainer for qat
crypto: caam - remove unused param of ctx_map_to_sec4_sg()
crypto: caam - remove unneeded edesc zeroization
crypto: atmel-aes - Reset the controller before each use
crypto: atmel-aes - properly set IV after {en,de}crypt
hwrng: core - Reset user selected rng by writing "" to rng_current
...
On a non-preemptible kernel, if KEYCTL_DH_COMPUTE is called with the
largest permitted inputs (16384 bits), the kernel spends 10+ seconds
doing modular exponentiation in mpi_powm() without rescheduling. If all
threads do it, it locks up the system. Moreover, it can cause
rcu_sched-stall warnings.
Notwithstanding the insanity of doing this calculation in kernel mode
rather than in userspace, fix it by calling cond_resched() as each bit
from the exponent is processed. It's still noninterruptible, but at
least it's preemptible now.
Do the cond_resched() once per bit rather than once per MPI limb because
each limb might still easily take 100+ milliseconds on slow CPUs.
Cc: <stable@vger.kernel.org> # v4.12+
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Many source files in the tree are missing licensing information, which
makes it harder for compliance tools to determine the correct license.
By default all files without license information are under the default
license of the kernel, which is GPL version 2.
Update the files which contain no license information with the 'GPL-2.0'
SPDX license identifier. The SPDX identifier is a legally binding
shorthand, which can be used instead of the full boiler plate text.
This patch is based on work done by Thomas Gleixner and Kate Stewart and
Philippe Ombredanne.
How this work was done:
Patches were generated and checked against linux-4.14-rc6 for a subset of
the use cases:
- file had no licensing information it it.
- file was a */uapi/* one with no licensing information in it,
- file was a */uapi/* one with existing licensing information,
Further patches will be generated in subsequent months to fix up cases
where non-standard license headers were used, and references to license
had to be inferred by heuristics based on keywords.
The analysis to determine which SPDX License Identifier to be applied to
a file was done in a spreadsheet of side by side results from of the
output of two independent scanners (ScanCode & Windriver) producing SPDX
tag:value files created by Philippe Ombredanne. Philippe prepared the
base worksheet, and did an initial spot review of a few 1000 files.
The 4.13 kernel was the starting point of the analysis with 60,537 files
assessed. Kate Stewart did a file by file comparison of the scanner
results in the spreadsheet to determine which SPDX license identifier(s)
to be applied to the file. She confirmed any determination that was not
immediately clear with lawyers working with the Linux Foundation.
Criteria used to select files for SPDX license identifier tagging was:
- Files considered eligible had to be source code files.
- Make and config files were included as candidates if they contained >5
lines of source
- File already had some variant of a license header in it (even if <5
lines).
All documentation files were explicitly excluded.
The following heuristics were used to determine which SPDX license
identifiers to apply.
- when both scanners couldn't find any license traces, file was
considered to have no license information in it, and the top level
COPYING file license applied.
For non */uapi/* files that summary was:
SPDX license identifier # files
---------------------------------------------------|-------
GPL-2.0 11139
and resulted in the first patch in this series.
If that file was a */uapi/* path one, it was "GPL-2.0 WITH
Linux-syscall-note" otherwise it was "GPL-2.0". Results of that was:
SPDX license identifier # files
---------------------------------------------------|-------
GPL-2.0 WITH Linux-syscall-note 930
and resulted in the second patch in this series.
- if a file had some form of licensing information in it, and was one
of the */uapi/* ones, it was denoted with the Linux-syscall-note if
any GPL family license was found in the file or had no licensing in
it (per prior point). Results summary:
SPDX license identifier # files
---------------------------------------------------|------
GPL-2.0 WITH Linux-syscall-note 270
GPL-2.0+ WITH Linux-syscall-note 169
((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause) 21
((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) 17
LGPL-2.1+ WITH Linux-syscall-note 15
GPL-1.0+ WITH Linux-syscall-note 14
((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause) 5
LGPL-2.0+ WITH Linux-syscall-note 4
LGPL-2.1 WITH Linux-syscall-note 3
((GPL-2.0 WITH Linux-syscall-note) OR MIT) 3
((GPL-2.0 WITH Linux-syscall-note) AND MIT) 1
and that resulted in the third patch in this series.
- when the two scanners agreed on the detected license(s), that became
the concluded license(s).
- when there was disagreement between the two scanners (one detected a
license but the other didn't, or they both detected different
licenses) a manual inspection of the file occurred.
- In most cases a manual inspection of the information in the file
resulted in a clear resolution of the license that should apply (and
which scanner probably needed to revisit its heuristics).
- When it was not immediately clear, the license identifier was
confirmed with lawyers working with the Linux Foundation.
- If there was any question as to the appropriate license identifier,
the file was flagged for further research and to be revisited later
in time.
In total, over 70 hours of logged manual review was done on the
spreadsheet to determine the SPDX license identifiers to apply to the
source files by Kate, Philippe, Thomas and, in some cases, confirmation
by lawyers working with the Linux Foundation.
Kate also obtained a third independent scan of the 4.13 code base from
FOSSology, and compared selected files where the other two scanners
disagreed against that SPDX file, to see if there was new insights. The
Windriver scanner is based on an older version of FOSSology in part, so
they are related.
Thomas did random spot checks in about 500 files from the spreadsheets
for the uapi headers and agreed with SPDX license identifier in the
files he inspected. For the non-uapi files Thomas did random spot checks
in about 15000 files.
In initial set of patches against 4.14-rc6, 3 files were found to have
copy/paste license identifier errors, and have been fixed to reflect the
correct identifier.
Additionally Philippe spent 10 hours this week doing a detailed manual
inspection and review of the 12,461 patched files from the initial patch
version early this week with:
- a full scancode scan run, collecting the matched texts, detected
license ids and scores
- reviewing anything where there was a license detected (about 500+
files) to ensure that the applied SPDX license was correct
- reviewing anything where there was no detection but the patch license
was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied
SPDX license was correct
This produced a worksheet with 20 files needing minor correction. This
worksheet was then exported into 3 different .csv files for the
different types of files to be modified.
These .csv files were then reviewed by Greg. Thomas wrote a script to
parse the csv files and add the proper SPDX tag to the file, in the
format that the file expected. This script was further refined by Greg
based on the output to detect more types of files automatically and to
distinguish between header and source .c files (which need different
comment types.) Finally Greg ran the script using the .csv files to
generate the patches.
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Using sg_miter_start and sg_miter_next, the buffer of an SG is kmap'ed
to *buff. The current code calls sg_miter_stop (and thus kunmap) on the
SG entry before the last access of *buff.
The patch moves the sg_miter_stop call after the last access to *buff to
ensure that the memory pointed to by *buff is still mapped.
Fixes: 4816c94064 ("lib/mpi: Fix SG miter leak")
Cc: <stable@vger.kernel.org>
Signed-off-by: Stephan Mueller <smueller@chronox.de>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Use just @ to denote comments which works with gcc and clang.
Otherwise clang reports an escape sequence error:
error: invalid % escape in inline assembly string
Use %0-%3 as operand references, this avoids:
error: invalid operand in inline asm: 'umull ${1:r}, ${0:r}, ${2:r}, ${3:r}'
Also remove superfluous casts on output operands to avoid warnings
such as:
warning: invalid use of a cast in an inline asm context requiring an l-value
Signed-off-by: Stefan Agner <stefan@agner.ch>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
In mpi_read_raw_from_sgl we may leak the SG miter resouces after
reading the leading zeroes. This patch fixes this by stopping the
iteration once the leading zeroes have been read.
Fixes: 127827b9c2 ("lib/mpi: Do not do sg_virt")
Reported-by: Nicolai Stange <nicstange@gmail.com>
Tested-by: Nicolai Stange <nicstange@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Currently the mpi SG helpers use sg_virt which is completely
broken. It happens to work with normal kernel memory but will
fail with anything that is not linearly mapped.
This patch fixes this by using the SG iterator helpers.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Every implementation of RSA that we have naturally generates
output with leading zeroes. The one and only user of RSA,
pkcs1pad wants to have those leading zeroes in place, in fact
because they are currently absent it has to write those zeroes
itself.
So we shouldn't be stripping leading zeroes in the first place.
In fact this patch makes rsa-generic produce output with fixed
length so that pkcs1pad does not need to do any extra work.
This patch also changes DH to use the new interface.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
mpi_read_from_buffer() and mpi_read_raw_data() do basically the same thing
except that the former extracts the number of payload bits from the first
two bytes of the input buffer.
Besides that, the data copying logic is exactly the same.
Replace the open coded buffer to MPI instance conversion by a call to
mpi_read_raw_data().
Signed-off-by: Nicolai Stange <nicstange@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
The first two bytes of the input buffer encode its expected length and
mpi_read_from_buffer() prints a console message if the given buffer is too
short.
However, there are some oddities with how this message is printed:
- It is printed at the default loglevel. This is different from the
one used in the case that the first two bytes' value is unsupportedly
large, i.e. KERN_INFO.
- The format specifier '%d' is used for unsigned ints.
- It prints the values of nread and *ret_nread. This is redundant since
the former is always the latter + 1.
Clean this up as follows:
- Use pr_info() rather than printk() with no loglevel.
- Use the format specifiers '%u' in place if '%d'.
- Do not print the redundant 'nread' but the more helpful 'nbytes' value.
Signed-off-by: Nicolai Stange <nicstange@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Currently, if the input buffer is shorter than the expected length as
indicated by its first two bytes, an MPI instance of this expected length
will be allocated and filled with as much data as is available. The rest
will remain uninitialized.
Instead of leaving this condition undetected, an error code should be
reported to the caller.
Since this situation indicates that the input buffer's first two bytes,
encoding the number of expected bits, are garbled, -EINVAL is appropriate
here.
If the input buffer is shorter than indicated by its first two bytes,
make mpi_read_from_buffer() return -EINVAL.
Get rid of the 'nread' variable: with the new semantics, the total number
of bytes read from the input buffer is known in advance.
Signed-off-by: Nicolai Stange <nicstange@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
mpi_read_from_buffer() reads a MPI from a buffer into a newly allocated
MPI instance. It expects the buffer's leading two bytes to contain the
number of bits, followed by the actual payload.
On failure, it returns NULL and updates the in/out argument ret_nread
somewhat inconsistently:
- If the given buffer is too short to contain the leading two bytes
encoding the number of bits or their value is unsupported, then
ret_nread will be cleared.
- If the allocation of the resulting MPI instance fails, ret_nread is left
as is.
The only user of mpi_read_from_buffer(), digsig_verify_rsa(), simply checks
for a return value of NULL and returns -ENOMEM if that happens.
While this is all of cosmetic nature only, there is another error condition
which currently isn't detectable by the caller of mpi_read_from_buffer():
if the given buffer is too small to hold the number of bits as encoded in
its first two bytes, the return value will be non-NULL and *ret_nread > 0.
In preparation of communicating this condition to the caller, let
mpi_read_from_buffer() return error values by means of the ERR_PTR()
mechanism.
Make the sole caller of mpi_read_from_buffer(), digsig_verify_rsa(),
check the return value for IS_ERR() rather than == NULL. If IS_ERR() is
true, return the associated error value rather than the fixed -ENOMEM.
Signed-off-by: Nicolai Stange <nicstange@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
The number of bits, nbits, is calculated in mpi_read_raw_data() as follows:
nbits = nbytes * 8;
Afterwards, the number of leading zero bits of the first byte get
subtracted:
nbits -= count_leading_zeros(buffer[0]);
However, count_leading_zeros() takes an unsigned long and thus,
the u8 gets promoted to an unsigned long.
Thus, the above doesn't subtract the number of leading zeros in the most
significant nonzero input byte from nbits, but the number of leading
zeros of the most significant nonzero input byte promoted to unsigned long,
i.e. BITS_PER_LONG - 8 too many.
Fix this by subtracting
count_leading_zeros(...) - (BITS_PER_LONG - 8)
from nbits only.
Fixes: e104599294 ("MPILIB: Provide a function to read raw data into an
MPI")
Signed-off-by: Nicolai Stange <nicstange@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
In mpi_read_raw_data(), unsigned nbits is calculated as follows:
nbits = nbytes * 8;
and redundantly cleared later on if nbytes == 0:
if (nbytes > 0)
...
else
nbits = 0;
Purge this redundant clearing for the sake of clarity.
Signed-off-by: Nicolai Stange <nicstange@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
mpi_set_buffer() has no in-tree users and similar functionality is provided
by mpi_read_raw_data().
Remove mpi_set_buffer().
Signed-off-by: Nicolai Stange <nicstange@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Within the copying loop in mpi_read_raw_from_sgl(), the last input SGE's
byte count gets artificially extended as follows:
if (sg_is_last(sg) && (len % BYTES_PER_MPI_LIMB))
len += BYTES_PER_MPI_LIMB - (len % BYTES_PER_MPI_LIMB);
Within the following byte copying loop, this causes reads beyond that
SGE's allocated buffer:
BUG: KASAN: slab-out-of-bounds in mpi_read_raw_from_sgl+0x331/0x650
at addr ffff8801e168d4d8
Read of size 1 by task systemd-udevd/721
[...]
Call Trace:
[<ffffffff818c4d35>] dump_stack+0xbc/0x117
[<ffffffff818c4c79>] ? _atomic_dec_and_lock+0x169/0x169
[<ffffffff814af5d1>] ? print_section+0x61/0xb0
[<ffffffff814b1109>] print_trailer+0x179/0x2c0
[<ffffffff814bc524>] object_err+0x34/0x40
[<ffffffff814bfdc7>] kasan_report_error+0x307/0x8c0
[<ffffffff814bf315>] ? kasan_unpoison_shadow+0x35/0x50
[<ffffffff814bf38e>] ? kasan_kmalloc+0x5e/0x70
[<ffffffff814c0ad1>] kasan_report+0x71/0xa0
[<ffffffff81938171>] ? mpi_read_raw_from_sgl+0x331/0x650
[<ffffffff814bf1a6>] __asan_load1+0x46/0x50
[<ffffffff81938171>] mpi_read_raw_from_sgl+0x331/0x650
[<ffffffff817f41b6>] rsa_verify+0x106/0x260
[<ffffffff817f40b0>] ? rsa_set_pub_key+0xf0/0xf0
[<ffffffff818edc79>] ? sg_init_table+0x29/0x50
[<ffffffff817f4d22>] ? pkcs1pad_sg_set_buf+0xb2/0x2e0
[<ffffffff817f5b74>] pkcs1pad_verify+0x1f4/0x2b0
[<ffffffff81831057>] public_key_verify_signature+0x3a7/0x5e0
[<ffffffff81830cb0>] ? public_key_describe+0x80/0x80
[<ffffffff817830f0>] ? keyring_search_aux+0x150/0x150
[<ffffffff818334a4>] ? x509_request_asymmetric_key+0x114/0x370
[<ffffffff814b83f0>] ? kfree+0x220/0x370
[<ffffffff818312c2>] public_key_verify_signature_2+0x32/0x50
[<ffffffff81830b5c>] verify_signature+0x7c/0xb0
[<ffffffff81835d0c>] pkcs7_validate_trust+0x42c/0x5f0
[<ffffffff813c391a>] system_verify_data+0xca/0x170
[<ffffffff813c3850>] ? top_trace_array+0x9b/0x9b
[<ffffffff81510b29>] ? __vfs_read+0x279/0x3d0
[<ffffffff8129372f>] mod_verify_sig+0x1ff/0x290
[...]
The exact purpose of the len extension isn't clear to me, but due to
its form, I suspect that it's a leftover somehow accounting for leading
zero bytes within the most significant output limb.
Note however that without that len adjustement, the total number of bytes
ever processed by the inner loop equals nbytes and thus, the last output
limb gets written at this point. Thus the net effect of the len adjustement
cited above is just to keep the inner loop running for some more
iterations, namely < BYTES_PER_MPI_LIMB ones, reading some extra bytes from
beyond the last SGE's buffer and discarding them afterwards.
Fix this issue by purging the extension of len beyond the last input SGE's
buffer length.
Fixes: 2d4d1eea54 ("lib/mpi: Add mpi sgl helpers")
Signed-off-by: Nicolai Stange <nicstange@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Within the byte reading loop in mpi_read_raw_sgl(), there are two
housekeeping indices used, z and x.
At all times, the index z represents the number of output bytes covered
by the input SGEs for which processing has completed so far. This includes
any leading zero bytes within the most significant limb.
The index x changes its meaning after the first outer loop's iteration
though: while processing the first input SGE, it represents
"number of leading zero bytes in most significant output limb" +
"current position within current SGE"
For the remaining SGEs OTOH, x corresponds just to
"current position within current SGE"
After all, it is only the sum of z and x that has any meaning for the
output buffer and thus, the
"number of leading zero bytes in most significant output limb"
part can be moved away from x into z from the beginning, opening up the
opportunity for cleaner code.
Before the outer loop iterating over the SGEs, don't initialize z with
zero, but with the number of leading zero bytes in the most significant
output limb. For the inner loop iterating over a single SGE's bytes,
get rid of the buf_shift offset to x' bounds and let x run from zero to
sg->length - 1.
Signed-off-by: Nicolai Stange <nicstange@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
The number of bits, nbits, is calculated in mpi_read_raw_from_sgl() as
follows:
nbits = nbytes * 8;
Afterwards, the number of leading zero bits of the first byte get
subtracted:
nbits -= count_leading_zeros(*(u8 *)(sg_virt(sgl) + lzeros));
However, count_leading_zeros() takes an unsigned long and thus,
the u8 gets promoted to an unsigned long.
Thus, the above doesn't subtract the number of leading zeros in the most
significant nonzero input byte from nbits, but the number of leading
zeros of the most significant nonzero input byte promoted to unsigned long,
i.e. BITS_PER_LONG - 8 too many.
Fix this by subtracting
count_leading_zeros(...) - (BITS_PER_LONG - 8)
from nbits only.
Fixes: 2d4d1eea54 ("lib/mpi: Add mpi sgl helpers")
Signed-off-by: Nicolai Stange <nicstange@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
In mpi_read_raw_from_sgl(), unsigned nbits is calculated as follows:
nbits = nbytes * 8;
and redundantly cleared later on if nbytes == 0:
if (nbytes > 0)
...
else
nbits = 0;
Purge this redundant clearing for the sake of clarity.
Signed-off-by: Nicolai Stange <nicstange@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
At the very beginning of mpi_read_raw_from_sgl(), the leading zeros of
the input scatterlist are counted:
lzeros = 0;
for_each_sg(sgl, sg, ents, i) {
...
if (/* sg contains nonzero bytes */)
break;
/* sg contains nothing but zeros here */
ents--;
lzeros = 0;
}
Later on, the total number of trailing nonzero bytes is calculated by
subtracting the number of leading zero bytes from the total number of input
bytes:
nbytes -= lzeros;
However, since lzeros gets reset to zero for each completely zero leading
sg in the loop above, it doesn't include those.
Besides wasting resources by allocating a too large output buffer,
this mistake propagates into the calculation of x, the number of
leading zeros within the most significant output limb:
x = BYTES_PER_MPI_LIMB - nbytes % BYTES_PER_MPI_LIMB;
What's more, the low order bytes of the output, equal in number to the
extra bytes in nbytes, are left uninitialized.
Fix this by adjusting nbytes for each completely zero leading scatterlist
entry.
Fixes: 2d4d1eea54 ("lib/mpi: Add mpi sgl helpers")
Signed-off-by: Nicolai Stange <nicstange@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Currently, the nbytes local variable is calculated from the len argument
as follows:
... mpi_read_raw_from_sgl(..., unsigned int len)
{
unsigned nbytes;
...
if (!ents)
nbytes = 0;
else
nbytes = len - lzeros;
...
}
Given that nbytes is derived from len in a trivial way and that the len
argument is shadowed by a local len variable in several loops, this is just
confusing.
Rename the len argument to nbytes and get rid of the nbytes local variable.
Do the nbytes calculation in place.
Signed-off-by: Nicolai Stange <nicstange@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Currently, mpi_read_buffer() writes full limbs to the output buffer
and moves memory around to purge leading zero limbs afterwards.
However, with
commit 9cbe21d8f8 ("lib/mpi: only require buffers as big as needed for
the integer")
the caller is only required to provide a buffer large enough to hold the
result without the leading zeros.
This might result in a buffer overflow for small MP numbers with leading
zeros.
Fix this by coping the result to its final destination within the output
buffer and not copying the leading zeros at all.
Fixes: 9cbe21d8f8 ("lib/mpi: only require buffers as big as needed for
the integer")
Signed-off-by: Nicolai Stange <nicstange@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Currently, the endian conversion from CPU order to BE is open coded in
mpi_read_buffer().
Replace this by the centrally provided cpu_to_be*() macros.
Copy from the temporary storage on stack to the destination buffer
by means of memcpy().
Signed-off-by: Nicolai Stange <nicstange@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Currently, if the number of leading zeros is greater than fits into a
complete limb, mpi_read_buffer() skips them by iterating over them
limb-wise.
Instead of skipping the high order zero limbs within the loop as shown
above, adjust the copying loop's bounds.
Signed-off-by: Nicolai Stange <nicstange@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Currently, the endian conversion from CPU order to BE is open coded in
mpi_write_sgl().
Replace this by the centrally provided cpu_to_be*() macros.
Signed-off-by: Nicolai Stange <nicstange@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Within the copying loop in mpi_write_sgl(), we have
if (lzeros) {
mpi_limb_t *limb1 = (void *)p - sizeof(alimb);
mpi_limb_t *limb2 = (void *)p - sizeof(alimb)
+ lzeros;
*limb1 = *limb2;
...
}
where p points past the end of alimb2 which lives on the stack and contains
the current limb in BE order.
The purpose of the above is to shift the non-zero bytes of alimb2 to its
beginning in memory, i.e. to skip its leading zero bytes.
However, limb2 points somewhere into the middle of alimb2 and thus, reading
*limb2 pulls in lzero bytes from somewhere.
Indeed, KASAN splats:
BUG: KASAN: stack-out-of-bounds in mpi_write_to_sgl+0x4e3/0x6f0
at addr ffff8800cb04f601
Read of size 8 by task systemd-udevd/391
page:ffffea00032c13c0 count:0 mapcount:0 mapping: (null) index:0x0
flags: 0x3fff8000000000()
page dumped because: kasan: bad access detected
CPU: 3 PID: 391 Comm: systemd-udevd Tainted: G B L
4.5.0-next-20160316+ #12
[...]
Call Trace:
[<ffffffff8194889e>] dump_stack+0xdc/0x15e
[<ffffffff819487c2>] ? _atomic_dec_and_lock+0xa2/0xa2
[<ffffffff814892b5>] ? __dump_page+0x185/0x330
[<ffffffff8150ffd6>] kasan_report_error+0x5e6/0x8b0
[<ffffffff814724cd>] ? kzfree+0x2d/0x40
[<ffffffff819c5bce>] ? mpi_free_limb_space+0xe/0x20
[<ffffffff819c469e>] ? mpi_powm+0x37e/0x16f0
[<ffffffff815109f1>] kasan_report+0x71/0xa0
[<ffffffff819c0353>] ? mpi_write_to_sgl+0x4e3/0x6f0
[<ffffffff8150ed34>] __asan_load8+0x64/0x70
[<ffffffff819c0353>] mpi_write_to_sgl+0x4e3/0x6f0
[<ffffffff819bfe70>] ? mpi_set_buffer+0x620/0x620
[<ffffffff819c0e6f>] ? mpi_cmp+0xbf/0x180
[<ffffffff8186e282>] rsa_verify+0x202/0x260
What's more, since lzeros can be anything from 1 to sizeof(mpi_limb_t)-1,
the above will cause unaligned accesses which is bad on non-x86 archs.
Fix the issue, by preparing the starting point p for the upcoming copy
operation instead of shifting the source memory, i.e. alimb2.
Fixes: 2d4d1eea54 ("lib/mpi: Add mpi sgl helpers")
Signed-off-by: Nicolai Stange <nicstange@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Within the copying loop in mpi_write_sgl(), we have
if (lzeros) {
...
p -= lzeros;
y = lzeros;
}
p = p - (sizeof(alimb) - y);
If lzeros == 0, then y == 0, too. Thus, lzeros gets subtracted and added
back again to p.
Purge this redundancy.
Signed-off-by: Nicolai Stange <nicstange@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Within the copying loop in mpi_write_sgl(), we have
if (lzeros > 0) {
...
lzeros -= sizeof(alimb);
}
However, at this point, lzeros < sizeof(alimb) holds. Make this fact
explicit by rewriting the above to
if (lzeros) {
...
lzeros = 0;
}
Signed-off-by: Nicolai Stange <nicstange@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Currently, if the number of leading zeros is greater than fits into a
complete limb, mpi_write_sgl() skips them by iterating over them limb-wise.
However, it fails to adjust its internal leading zeros tracking variable,
lzeros, accordingly: it does a
p -= sizeof(alimb);
continue;
which should really have been a
lzeros -= sizeof(alimb);
continue;
Since lzeros never decreases if its initial value >= sizeof(alimb), nothing
gets copied by mpi_write_sgl() in that case.
Instead of skipping the high order zero limbs within the loop as shown
above, fix the issue by adjusting the copying loop's bounds.
Fixes: 2d4d1eea54 ("lib/mpi: Add mpi sgl helpers")
Signed-off-by: Nicolai Stange <nicstange@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
When we use CONFIG_PROFILE_ALL_BRANCHES, every 'if()' introduces
a static variable, but that is not allowed in 'extern inline'
functions:
mpi-inline.h:116:204: warning: '______f' is static but declared in inline function 'mpihelp_sub' which is not static
mpi-inline.h:113:184: warning: '______f' is static but declared in inline function 'mpihelp_sub' which is not static
mpi-inline.h:70:184: warning: '______f' is static but declared in inline function 'mpihelp_add' which is not static
mpi-inline.h:56:204: warning: '______f' is static but declared in inline function 'mpihelp_add_1' which is not static
This changes the MPI code to use 'static inline' instead, to get
rid of hundreds of warnings.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
A wrapper around the umull assembly instruction might reuse
the input register as an output, which is undefined on
some ARM machines, as pointed out by this assembler warning:
CC lib/mpi/generic_mpih-mul1.o
/tmp/ccxJuxIy.s: Assembler messages:
/tmp/ccxJuxIy.s:53: rdhi, rdlo and rm must all be different
CC lib/mpi/generic_mpih-mul2.o
/tmp/ccI0scAD.s: Assembler messages:
/tmp/ccI0scAD.s:53: rdhi, rdlo and rm must all be different
CC lib/mpi/generic_mpih-mul3.o
/tmp/ccMvVQcp.s: Assembler messages:
/tmp/ccMvVQcp.s:53: rdhi, rdlo and rm must all be different
This changes the constraints to force different registers to
be used as output.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
The limbs are integers in the host endianness, so we can't simply
iterate over the individual bytes. The current code happens to work on
little-endian, because the order of the limbs in the MPI array is the
same as the order of the bytes in each limb, but it breaks on
big-endian.
Fixes: 0f74fbf77d ("MPI: Fix mpi_read_buffer")
Signed-off-by: Michal Marek <mmarek@suse.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Since mpi_write_to_sgl and mpi_read_buffer explicitly left-align the
integers being written it makes no sense to require a buffer big enough for
the number + the leading zero bytes which are not written. The error
returned also doesn't convey any information. So instead require only the
size needed and return -EOVERFLOW to signal when buffer too short.
Signed-off-by: Andrew Zaborowski <andrew.zaborowski@intel.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
The asm-generic changes for 4.4 are mostly a series from Christoph Hellwig
to clean up various abuses of headers in there. The patch to rename the
io-64-nonatomic-*.h headers caused some conflicts with new users, so I
added a workaround that we can remove in the next merge window.
The only other patch is a warning fix from Marek Vasut
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1
iQIVAwUAVjzaf2CrR//JCVInAQImmhAA20fZ91sUlnA5skKNPT1phhF6Z7UF2Sx5
nPKcHQD3HA3lT1OKfPBYvCo+loYflvXFLaQThVylVcnE/8ecAEMtft4nnGW2nXvh
sZqHIZ8fszTB53cynAZKTjdobD1wu33Rq7XRzg0ugn1mdxFkOzCHW/xDRvWRR5TL
rdQjzzgvn2PNlqFfHlh6cZ5ykShM36AIKs3WGA0H0Y/aYsE9GmDOAUp41q1mLXnA
4lKQaIxoeOa+kmlsUB0wEHUecWWWJH4GAP+CtdKzTX9v12bGNhmiKUMCETG78BT3
uL8irSqaViNwSAS9tBxSpqvmVUsa5aCA5M3MYiO+fH9ifd7wbR65g/wq39D3Pc01
KnZ3BNVRW5XSA3c86pr8vbg/HOynUXK8TN0lzt6rEk8bjoPBNEDy5YWzy0t6reVe
wX65F+ver8upjOKe9yl2Jsg+5Kcmy79GyYjLUY3TU2mZ+dIdScy/jIWatXe/OTKZ
iB4Ctc4MDe9GDECmlPOWf98AXqsBUuKQiWKCN/OPxLtFOeWBvi4IzvFuO8QvnL9p
jZcRDmIlIWAcDX/2wMnLjV+Hqi3EeReIrYznxTGnO7HHVInF555GP51vFaG5k+SN
smJQAB0/sostmC1OCCqBKq5b6/li95/No7+0v0SUhJJ5o76AR5CcNsnolXesw1fu
vTUkB/I66Hk=
=dQKG
-----END PGP SIGNATURE-----
Merge tag 'asm-generic-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/asm-generic
Pull asm-generic cleanups from Arnd Bergmann:
"The asm-generic changes for 4.4 are mostly a series from Christoph
Hellwig to clean up various abuses of headers in there. The patch to
rename the io-64-nonatomic-*.h headers caused some conflicts with new
users, so I added a workaround that we can remove in the next merge
window.
The only other patch is a warning fix from Marek Vasut"
* tag 'asm-generic-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/asm-generic:
asm-generic: temporarily add back asm-generic/io-64-nonatomic*.h
asm-generic: cmpxchg: avoid warnings from macro-ized cmpxchg() implementations
gpio-mxc: stop including <asm-generic/bug>
n_tracesink: stop including <asm-generic/bug>
n_tracerouter: stop including <asm-generic/bug>
mlx5: stop including <asm-generic/kmap_types.h>
hifn_795x: stop including <asm-generic/kmap_types.h>
drbd: stop including <asm-generic/kmap_types.h>
move count_zeroes.h out of asm-generic
move io-64-nonatomic*.h out of asm-generic
The patch fixes the analysis of the input data which contains an off
by one.
The issue is visible when the SGL contains one byte per SG entry.
The code for checking for zero bytes does not operate on the data byte.
Signed-off-by: Stephan Mueller <smueller@chronox.de>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This header contains a few helpers currenly only used by the mpi
implementation, and not default implementation of architecture code.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Add mpi_read_raw_from_sgl and mpi_write_to_sgl helpers.
Signed-off-by: Tadeusz Struk <tadeusz.struk@intel.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Change mpi_read_buffer to return a number without leading zeros
so that mpi_read_buffer and mpi_get_buffer return the same thing.
Signed-off-by: Tadeusz Struk <tadeusz.struk@intel.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Pull crypto update from Herbert Xu:
"Here is the crypto update for 4.2:
API:
- Convert RNG interface to new style.
- New AEAD interface with one SG list for AD and plain/cipher text.
All external AEAD users have been converted.
- New asymmetric key interface (akcipher).
Algorithms:
- Chacha20, Poly1305 and RFC7539 support.
- New RSA implementation.
- Jitter RNG.
- DRBG is now seeded with both /dev/random and Jitter RNG. If kernel
pool isn't ready then DRBG will be reseeded when it is.
- DRBG is now the default crypto API RNG, replacing krng.
- 842 compression (previously part of powerpc nx driver).
Drivers:
- Accelerated SHA-512 for arm64.
- New Marvell CESA driver that supports DMA and more algorithms.
- Updated powerpc nx 842 support.
- Added support for SEC1 hardware to talitos"
* git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6: (292 commits)
crypto: marvell/cesa - remove COMPILE_TEST dependency
crypto: algif_aead - Temporarily disable all AEAD algorithms
crypto: af_alg - Forbid the use internal algorithms
crypto: echainiv - Only hold RNG during initialisation
crypto: seqiv - Add compatibility support without RNG
crypto: eseqiv - Offer normal cipher functionality without RNG
crypto: chainiv - Offer normal cipher functionality without RNG
crypto: user - Add CRYPTO_MSG_DELRNG
crypto: user - Move cryptouser.h to uapi
crypto: rng - Do not free default RNG when it becomes unused
crypto: skcipher - Allow givencrypt to be NULL
crypto: sahara - propagate the error on clk_disable_unprepare() failure
crypto: rsa - fix invalid select for AKCIPHER
crypto: picoxcell - Update to the current clk API
crypto: nx - Check for bogus firmware properties
crypto: marvell/cesa - add DT bindings documentation
crypto: marvell/cesa - add support for Kirkwood and Dove SoCs
crypto: marvell/cesa - add support for Orion SoCs
crypto: marvell/cesa - add allhwsupport module parameter
crypto: marvell/cesa - add support for all armada SoCs
...
Added a mpi_read_buf() helper function to export MPI to a buf provided by
the user, and a mpi_get_size() helper, that tells the user how big the buf is.
Changed mpi_free to use kzfree instead of kfree because it is used to free
crypto keys.
Signed-off-by: Tadeusz Struk <tadeusz.struk@intel.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
If u and v both represent negative integers and their limb counts
happen to differ, mpi_cmp will always return a positive value - this
is obviously bogus. u is smaller than v if and only if it is larger in
absolute value.
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Dmitry Kasatkin <dmitry.kasatkin@gmail.com>
The macro MPN_COPY_INCR this occurs in isn't used anywhere.
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: David Howells <dhowells@redhat.com>
The condition preceding 'return 1;' makes my head hurt. At this point,
we know that u and v have the same sign; if they are negative, they
compare opposite to how their absolute values compare (which
mpihelp_cmp found for us), otherwise cmp itself is the
answer. Negating cmp is ok since mpihelp_cmp returns {-1,0,1};
-INT_MIN==INT_MIN won't bite us.
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Dmitry Kasatkin <dmitry.kasatkin@gmail.com>
This patch fixes lack of license, otherwise mpi.ko taints kernel.
Signed-off-by: Konstantin Khlebnikov <khlebnikov@openvz.org>
Signed-off-by: David Howells <dhowells@redhat.com>
Remove the compile warning for __udiv_qrnnd not having a prototype.
Use the __builtin_alpha_umulh introduced in gcc 4.0.
Reviewed-and-Tested-by: Matt Turner <mattst88@gmail.com>
Signed-off-by: Matt Turner <mattst88@gmail.com>
Signed-off-by: Richard Henderson <rth@twiddle.net>
For 'while' looping, need stop when 'nbytes == 0', or will cause issue.
('nbytes' is size_t which is always bigger or equal than zero).
The related warning: (with EXTRA_CFLAGS=-W)
lib/mpi/mpicoder.c:40:2: warning: comparison of unsigned expression >= 0 is always true [-Wtype-limits]
Signed-off-by: Chen Gang <gang.chen@asianux.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: David Howells <dhowells@redhat.com>
Cc: James Morris <james.l.morris@oracle.com>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: David Howells <dhowells@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
James Hogan
Linus Torvalds
Eric Biggers
Greg Kroah-Hartman
Herbert Xu
Stephan Mueller
Stefan Agner
Andrey Ryabinin
Nicolai Stange
Arnd Bergmann
Michal Marek
Andrzej Zaborowski
Christoph Hellwig
Tadeusz Struk
Jaedon Shin
Rasmus Villemoes
Konstantin Khlebnikov
Richard Henderson
Chen Gang