This is a note to let you know that I've just added the patch titled crypto: aesni - check walk.nbytes instead of err to the 5.14-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-aesni-check-walk.nbytes-instead-of-err.patch and it can be found in the queue-5.14 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit a12ab0c57a289686f46c9382df3b2702fade4b6a Author: Shreyansh Chouhan <chouhan.shreyansh630@xxxxxxxxx> Date: Sat Sep 11 16:37:59 2021 +0530 crypto: aesni - check walk.nbytes instead of err [ Upstream commit a2d3cbc80d2527b435154ff0f89b56ef4b84370f ] In the code for xts_crypt(), we check for the err value returned by skcipher_walk_virt() and return from the function if it is non zero. However, skcipher_walk_virt() can set walk.nbytes to 0, which would cause us to call kernel_fpu_begin(), and then skip the kernel_fpu_end() call. This patch checks for the walk.nbytes value instead, and returns if walk.nbytes is 0. This prevents us from calling kernel_fpu_begin() in the first place and also covers the case of having a non zero err value returned from skcipher_walk_virt(). Reported-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx> Signed-off-by: Shreyansh Chouhan <chouhan.shreyansh630@xxxxxxxxx> Signed-off-by: Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/arch/x86/crypto/aesni-intel_glue.c b/arch/x86/crypto/aesni-intel_glue.c index 0fc961bef299c..e09f4672dd382 100644 --- a/arch/x86/crypto/aesni-intel_glue.c +++ b/arch/x86/crypto/aesni-intel_glue.c @@ -866,7 +866,7 @@ static int xts_crypt(struct skcipher_request *req, bool encrypt) req = &subreq; err = skcipher_walk_virt(&walk, req, false); - if (err) + if (!walk.nbytes) return err; } else { tail = 0;