Minki/linux
1
0
Fork 1
mirror of https://github.com/torvalds/linux.git synced 2024-11-11 06:31:49 +00:00
Code Issues Packages Projects Releases Wiki Activity

crypto: x86/aesni-gcm - fix crash on empty plaintext

Browse Source 
gcmaes_crypt_by_sg() dereferences the NULL pointer returned by
scatterwalk_ffwd() when encrypting an empty plaintext and the source
scatterlist ends immediately after the associated data.

Fix it by only fast-forwarding to the src/dst data scatterlists if the
data length is nonzero.

This bug is reproduced by the "rfc4543(gcm(aes))" test vectors when run
with the new AEAD test manager.

Fixes: e845520707 ("crypto: aesni - Update aesni-intel_glue to use scatter/gather")
Cc: <stable@vger.kernel.org> # v4.17+
Cc: Dave Watson <davejwatson@fb.com>
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This commit is contained in:
Eric Biggers 2019-01-31 23:51:40 -08:00 committed by Herbert Xu
parent 2060e284e9
commit 3af3496395
1 changed files with 8 additions and 5 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

5
arch/x86/crypto/aesni-intel_glue.c
View File

@ -813,12 +813,15 @@ static int gcmaes_crypt_by_sg(bool enc, struct aead_request *req,
scatterwalk_map_and_copy(assoc, req->src, 0, assoclen, 0);
}
if (left) {
src_sg = scatterwalk_ffwd(src_start, req->src, req->assoclen);
scatterwalk_start(&src_sg_walk, src_sg);
if (req->src != req->dst) {
dst_sg = scatterwalk_ffwd(dst_start, req->dst, req->assoclen);
dst_sg = scatterwalk_ffwd(dst_start, req->dst,
req->assoclen);
scatterwalk_start(&dst_sg_walk, dst_sg);
}
}
kernel_fpu_begin();
gcm_tfm->init(aes_ctx, &data, iv,