This is a note to let you know that I've just added the patch titled
crypto: algif_aead - fix reference counting of null skcipher
to the 4.14-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git%3Ba=su...
The filename of the patch is: crypto-algif_aead-fix-reference-counting-of-null-skcipher.patch and it can be found in the queue-4.14 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree, please let stable@vger.kernel.org know about it.
From b32a7dc8aef1882fbf983eb354837488cc9d54dc Mon Sep 17 00:00:00 2001
From: Eric Biggers ebiggers@google.com Date: Mon, 27 Nov 2017 23:23:05 -0800 Subject: crypto: algif_aead - fix reference counting of null skcipher
From: Eric Biggers ebiggers@google.com
commit b32a7dc8aef1882fbf983eb354837488cc9d54dc upstream.
In the AEAD interface for AF_ALG, the reference to the "null skcipher" held by each tfm was being dropped in the wrong place -- when each af_alg_ctx was freed instead of when the aead_tfm was freed. As discovered by syzkaller, a specially crafted program could use this to cause the null skcipher to be freed while it is still in use.
Fix it by dropping the reference in the right place.
Fixes: 72548b093ee3 ("crypto: algif_aead - copy AAD from src to dst") Reported-by: syzbot syzkaller@googlegroups.com Signed-off-by: Eric Biggers ebiggers@google.com Reviewed-by: Stephan Mueller smueller@chronox.de Signed-off-by: Herbert Xu herbert@gondor.apana.org.au Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- crypto/algif_aead.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
--- a/crypto/algif_aead.c +++ b/crypto/algif_aead.c @@ -503,6 +503,7 @@ static void aead_release(void *private) struct aead_tfm *tfm = private;
crypto_free_aead(tfm->aead); + crypto_put_default_null_skcipher2(); kfree(tfm); }
@@ -535,7 +536,6 @@ static void aead_sock_destruct(struct so unsigned int ivlen = crypto_aead_ivsize(tfm);
af_alg_pull_tsgl(sk, ctx->used, NULL, 0); - crypto_put_default_null_skcipher2(); sock_kzfree_s(sk, ctx->iv, ivlen); sock_kfree_s(sk, ctx, ctx->len); af_alg_release_parent(sk);
Patches currently in stable-queue which might be from ebiggers@google.com are
queue-4.14/crypto-algif_aead-fix-reference-counting-of-null-skcipher.patch queue-4.14/crypto-salsa20-fix-blkcipher_walk-api-usage.patch queue-4.14/crypto-rsa-fix-buffer-overread-when-stripping-leading-zeroes.patch queue-4.14/crypto-hmac-require-that-the-underlying-hash-algorithm-is-unkeyed.patch queue-4.14/crypto-af_alg-fix-null-pointer-dereference-in.patch