This is a note to let you know that I've just added the patch titled crypto: af_alg - fix NULL pointer dereference in to the 4.14-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: crypto-af_alg-fix-null-pointer-dereference-in.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@xxxxxxxxxxxxxxx> know about it. >From 887207ed9e5812ed9239b6d07185a2d35dda91db Mon Sep 17 00:00:00 2001 From: Eric Biggers <ebiggers@xxxxxxxxxx> Date: Tue, 28 Nov 2017 00:46:24 -0800 Subject: crypto: af_alg - fix NULL pointer dereference in From: Eric Biggers <ebiggers@xxxxxxxxxx> commit 887207ed9e5812ed9239b6d07185a2d35dda91db upstream. af_alg_free_areq_sgls() If allocating the ->tsgl member of 'struct af_alg_async_req' failed, during cleanup we dereferenced the NULL ->tsgl pointer in af_alg_free_areq_sgls(), because ->tsgl_entries was nonzero. Fix it by only freeing the ->tsgl list if it is non-NULL. This affected both algif_skcipher and algif_aead. Fixes: e870456d8e7c ("crypto: algif_skcipher - overhaul memory management") Fixes: d887c52d6ae4 ("crypto: algif_aead - overhaul memory management") Reported-by: syzbot <syzkaller@xxxxxxxxxxxxxxxx> Signed-off-by: Eric Biggers <ebiggers@xxxxxxxxxx> Reviewed-by: Stephan Mueller <smueller@xxxxxxxxxx> Signed-off-by: Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- crypto/af_alg.c | 13 +++++++------ 1 file changed, 7 insertions(+), 6 deletions(-) --- a/crypto/af_alg.c +++ b/crypto/af_alg.c @@ -699,14 +699,15 @@ void af_alg_free_areq_sgls(struct af_alg } tsgl = areq->tsgl; - for_each_sg(tsgl, sg, areq->tsgl_entries, i) { - if (!sg_page(sg)) - continue; - put_page(sg_page(sg)); - } + if (tsgl) { + for_each_sg(tsgl, sg, areq->tsgl_entries, i) { + if (!sg_page(sg)) + continue; + put_page(sg_page(sg)); + } - if (areq->tsgl && areq->tsgl_entries) sock_kfree_s(sk, tsgl, areq->tsgl_entries * sizeof(*tsgl)); + } } EXPORT_SYMBOL_GPL(af_alg_free_areq_sgls); Patches currently in stable-queue which might be from ebiggers@xxxxxxxxxx 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