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| author | Weiming Shi <bestswngs@gmail.com> | 2026-04-30 10:36:34 -0700 |
|---|---|---|
| committer | Herbert Xu <herbert@gondor.apana.org.au> | 2026-05-07 16:10:03 +0800 |
| commit | f7dd32c5179d7755de18e21d5674b08f9e5cb180 (patch) | |
| tree | da5e7507df20c60558acec251476ba0a9c97a22b /crypto | |
| parent | 2d7b2cfc59998baf5e8622a24dc28f69a5212e06 (diff) | |
| download | linux-next-history-f7dd32c5179d7755de18e21d5674b08f9e5cb180.tar.gz | |
crypto: asymmetric_keys - fix OOB read in pefile_digest_pe_contents
pefile_digest_pe_contents() computes the trailing-data hash length as
pelen - (hashed_bytes + certs_size). A crafted PE can make the addition
exceed pelen, causing the unsigned subtraction to underflow to ~4 GiB.
This is passed to crypto_shash_update() which reads out of bounds and
panics on unmapped vmalloc guard pages.
BUG: unable to handle page fault for address: ffffc900038d8000
Oops: Oops: 0000 [#1] SMP KASAN NOPTI
RIP: 0010:sha256_blocks_generic (lib/crypto/sha256.c:152)
Call Trace:
<TASK>
__sha256_update (lib/crypto/sha256.c:208)
crypto_sha256_update (crypto/sha256.c:142)
verify_pefile_signature (crypto/asymmetric_keys/verify_pefile.c:436)
kexec_kernel_verify_pe_sig (kernel/kexec_file.c:151)
__do_sys_kexec_file_load (kernel/kexec_file.c:406)
do_syscall_64 (arch/x86/entry/syscall_64.c:94)
entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:121)
</TASK>
Kernel panic - not syncing: Fatal exception
Validate that the addition does not overflow and the result does not
exceed pelen before the subtraction. Return -ELIBBAD on failure.
Fixes: af316fc442ef ("pefile: Digest the PE binary and compare to the PKCS#7 data")
Reported-by: Xiang Mei <xmei5@asu.edu>
Signed-off-by: Weiming Shi <bestswngs@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Diffstat (limited to 'crypto')
| -rw-r--r-- | crypto/asymmetric_keys/verify_pefile.c | 2 |
1 files changed, 2 insertions, 0 deletions
diff --git a/crypto/asymmetric_keys/verify_pefile.c b/crypto/asymmetric_keys/verify_pefile.c index 1f3b227ba7f22..cec99db14129a 100644 --- a/crypto/asymmetric_keys/verify_pefile.c +++ b/crypto/asymmetric_keys/verify_pefile.c @@ -305,6 +305,8 @@ static int pefile_digest_pe_contents(const void *pebuf, unsigned int pelen, if (pelen > hashed_bytes) { tmp = hashed_bytes + ctx->certs_size; + if (tmp <= hashed_bytes || pelen < tmp) + return -ELIBBAD; ret = crypto_shash_update(desc, pebuf + hashed_bytes, pelen - tmp); |