From: Eric Biggers <ebiggers@kernel.org>
To: linux-crypto@vger.kernel.org, Herbert Xu <herbert@gondor.apana.org.au>
Cc: linux-kernel@vger.kernel.org,
"Jason A . Donenfeld" <Jason@zx2c4.com>,
stable@vger.kernel.org, Dave Watson <davejwatson@fb.com>
Subject: [RFC/RFT PATCH 05/15] crypto: x86/aesni-gcm - fix crash on empty plaintext
Date: Wed, 23 Jan 2019 14:49:16 -0800 [thread overview]
Message-ID: <20190123224926.250525-6-ebiggers@kernel.org> (raw)
In-Reply-To: <20190123224926.250525-1-ebiggers@kernel.org>
From: Eric Biggers <ebiggers@google.com>
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: e845520707f8 ("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>
---
arch/x86/crypto/aesni-intel_glue.c | 13 ++++++++-----
1 file changed, 8 insertions(+), 5 deletions(-)
diff --git a/arch/x86/crypto/aesni-intel_glue.c b/arch/x86/crypto/aesni-intel_glue.c
index 9b5ccde3ef31..1e3d2102033a 100644
--- a/arch/x86/crypto/aesni-intel_glue.c
+++ b/arch/x86/crypto/aesni-intel_glue.c
@@ -813,11 +813,14 @@ static int gcmaes_crypt_by_sg(bool enc, struct aead_request *req,
scatterwalk_map_and_copy(assoc, req->src, 0, assoclen, 0);
}
- 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);
- scatterwalk_start(&dst_sg_walk, dst_sg);
+ 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);
+ scatterwalk_start(&dst_sg_walk, dst_sg);
+ }
}
kernel_fpu_begin();
--
2.20.1.321.g9e740568ce-goog
next prev parent reply other threads:[~2019-01-23 22:54 UTC|newest]
Thread overview: 10+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <20190123224926.250525-1-ebiggers@kernel.org>
2019-01-23 22:49 ` [RFC/RFT PATCH 01/15] crypto: aegis - fix handling chunked inputs Eric Biggers
2019-01-23 22:49 ` [RFC/RFT PATCH 02/15] crypto: morus " Eric Biggers
2019-01-31 9:05 ` Ondrej Mosnacek
2019-02-01 5:25 ` Eric Biggers
2019-01-23 22:49 ` [RFC/RFT PATCH 03/15] crypto: x86/aegis - fix handling chunked inputs and MAY_SLEEP Eric Biggers
2019-01-23 22:49 ` [RFC/RFT PATCH 04/15] crypto: x86/morus " Eric Biggers
2019-01-23 22:49 ` Eric Biggers [this message]
2019-01-23 22:49 ` [RFC/RFT PATCH 06/15] crypto: ahash - fix another early termination in hash walk Eric Biggers
2019-01-23 22:49 ` [RFC/RFT PATCH 07/15] crypto: arm64/aes-neonbs - fix returning final keystream block Eric Biggers
2019-01-24 12:11 ` Ard Biesheuvel
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20190123224926.250525-6-ebiggers@kernel.org \
--to=ebiggers@kernel.org \
--cc=Jason@zx2c4.com \
--cc=davejwatson@fb.com \
--cc=herbert@gondor.apana.org.au \
--cc=linux-crypto@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=stable@vger.kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).