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| author | Horia Geanta <horia.geanta@freescale.com> | 2013-11-28 15:11:15 +0200 |
|---|---|---|
| committer | Herbert Xu <herbert@gondor.apana.org.au> | 2013-11-28 22:25:17 +0800 |
| commit | 5638cabf3e4883f38dfb246c30980cebf694fbda (patch) | |
| tree | d0764b8966704d6d0455d2a9d22de611dfaa812a /crypto/ccm.c | |
| parent | 9dda2769af4f3f3093434648c409bb351120d9e8 (diff) | |
| download | linux-5638cabf3e4883f38dfb246c30980cebf694fbda.tar.gz linux-5638cabf3e4883f38dfb246c30980cebf694fbda.tar.bz2 linux-5638cabf3e4883f38dfb246c30980cebf694fbda.zip | |
crypto: ccm - Fix handling of zero plaintext when computing mac
There are cases when cryptlen can be zero in crypto_ccm_auth():
-encryptiom: input scatterlist length is zero (no plaintext)
-decryption: input scatterlist contains only the mac
plus the condition of having different source and destination buffers
(or else scatterlist length = max(plaintext_len, ciphertext_len)).
These are not handled correctly, leading to crashes like:
root@p4080ds:~/crypto# insmod tcrypt.ko mode=45
------------[ cut here ]------------
kernel BUG at crypto/scatterwalk.c:37!
Oops: Exception in kernel mode, sig: 5 [#1]
SMP NR_CPUS=8 P4080 DS
Modules linked in: tcrypt(+) crc32c xts xcbc vmac pcbc ecb gcm ghash_generic gf128mul ccm ctr seqiv
CPU: 3 PID: 1082 Comm: cryptomgr_test Not tainted 3.11.0 #14
task: ee12c5b0 ti: eecd0000 task.ti: eecd0000
NIP: c0204d98 LR: f9225848 CTR: c0204d80
REGS: eecd1b70 TRAP: 0700 Not tainted (3.11.0)
MSR: 00029002 <CE,EE,ME> CR: 22044022 XER: 20000000
GPR00: f9225c94 eecd1c20 ee12c5b0 eecd1c28 ee879400 ee879400 00000000 ee607464
GPR08: 00000001 00000001 00000000 006b0000 c0204d80 00000000 00000002 c0698e20
GPR16: ee987000 ee895000 fffffff4 ee879500 00000100 eecd1d58 00000001 00000000
GPR24: ee879400 00000020 00000000 00000000 ee5b2800 ee607430 00000004 ee607460
NIP [c0204d98] scatterwalk_start+0x18/0x30
LR [f9225848] get_data_to_compute+0x28/0x2f0 [ccm]
Call Trace:
[eecd1c20] [f9225974] get_data_to_compute+0x154/0x2f0 [ccm] (unreliable)
[eecd1c70] [f9225c94] crypto_ccm_auth+0x184/0x1d0 [ccm]
[eecd1cb0] [f9225d40] crypto_ccm_encrypt+0x60/0x2d0 [ccm]
[eecd1cf0] [c020d77c] __test_aead+0x3ec/0xe20
[eecd1e20] [c020f35c] test_aead+0x6c/0xe0
[eecd1e40] [c020f420] alg_test_aead+0x50/0xd0
[eecd1e60] [c020e5e4] alg_test+0x114/0x2e0
[eecd1ee0] [c020bd1c] cryptomgr_test+0x4c/0x60
[eecd1ef0] [c0047058] kthread+0xa8/0xb0
[eecd1f40] [c000eb0c] ret_from_kernel_thread+0x5c/0x64
Instruction dump:
0f080000 81290024 552807fe 0f080000 5529003a 4bffffb4 90830000 39400000
39000001 8124000c 2f890000 7d28579e <0f090000> 81240008 91230004 4e800020
---[ end trace 6d652dfcd1be37bd ]---
Cc: <stable@vger.kernel.org>
Cc: Jussi Kivilinna <jussi.kivilinna@mbnet.fi>
Signed-off-by: Horia Geanta <horia.geanta@freescale.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Diffstat (limited to 'crypto/ccm.c')
| -rw-r--r-- | crypto/ccm.c | 3 |
1 files changed, 2 insertions, 1 deletions
diff --git a/crypto/ccm.c b/crypto/ccm.c index 3e05499d183a..1df84217f7c9 100644 --- a/crypto/ccm.c +++ b/crypto/ccm.c @@ -271,7 +271,8 @@ static int crypto_ccm_auth(struct aead_request *req, struct scatterlist *plain, } /* compute plaintext into mac */ - get_data_to_compute(cipher, pctx, plain, cryptlen); + if (cryptlen) + get_data_to_compute(cipher, pctx, plain, cryptlen); out: return err; |