diff options
| author | Joy Latten <latten@austin.ibm.com> | 2008-03-12 12:17:45 +0800 |
|---|---|---|
| committer | Chris Wright <chrisw@sous-sol.org> | 2008-03-24 11:47:12 -0700 |
| commit | 0c7ac6f8e603b7e33c7ee268c30f2de59111951c (patch) | |
| tree | 6f778315df85f98135e4d53dcbc25a8098d8a559 /crypto | |
| parent | 0ad5232c1ccba61437676cdb88d030b1c369dec7 (diff) | |
CRYPTO xcbc: Fix crash with IPsec
[ Upstream commit: 2f40a178e70030c4712fe63807c883f34c3645eb ]
When using aes-xcbc-mac for authentication in IPsec,
the kernel crashes. It seems this algorithm doesn't
account for the space IPsec may make in scatterlist for authtag.
Thus when crypto_xcbc_digest_update2() gets called,
nbytes may be less than sg[i].length.
Since nbytes is an unsigned number, it wraps
at the end of the loop allowing us to go back
into loop and causing crash in memcpy.
I used update function in digest.c to model this fix.
Please let me know if it looks ok.
Signed-off-by: Joy Latten <latten@austin.ibm.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Chris Wright <chrisw@sous-sol.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Diffstat (limited to 'crypto')
| -rw-r--r-- | crypto/xcbc.c | 6 |
1 files changed, 5 insertions, 1 deletions
diff --git a/crypto/xcbc.c b/crypto/xcbc.c index ac68f3b62fde..a957373832b3 100644 --- a/crypto/xcbc.c +++ b/crypto/xcbc.c @@ -124,6 +124,11 @@ static int crypto_xcbc_digest_update2(struct hash_desc *pdesc, unsigned int offset = sg[i].offset; unsigned int slen = sg[i].length; + if (unlikely(slen > nbytes)) + slen = nbytes; + + nbytes -= slen; + while (slen > 0) { unsigned int len = min(slen, ((unsigned int)(PAGE_SIZE)) - offset); char *p = crypto_kmap(pg, 0) + offset; @@ -177,7 +182,6 @@ static int crypto_xcbc_digest_update2(struct hash_desc *pdesc, offset = 0; pg++; } - nbytes-=sg[i].length; i++; } while (nbytes>0); |