@@ -1109,7 +1109,7 @@ static int __driver_rfc4106_decrypt(struct aead_request *req)
src = kmalloc(req->cryptlen + req->assoclen, GFP_ATOMIC);
if (!src)
return -ENOMEM;
- assoc = (src + req->cryptlen + auth_tag_len);
+ assoc = (src + req->cryptlen);
scatterwalk_map_and_copy(src, req->src, 0, req->cryptlen, 0);
scatterwalk_map_and_copy(assoc, req->assoc, 0,
req->assoclen, 0);
@@ -1134,7 +1134,7 @@ static int __driver_rfc4106_decrypt(struct aead_request *req)
scatterwalk_done(&src_sg_walk, 0, 0);
scatterwalk_done(&assoc_sg_walk, 0, 0);
} else {
- scatterwalk_map_and_copy(dst, req->dst, 0, req->cryptlen, 1);
+ scatterwalk_map_and_copy(dst, req->dst, 0, tempCipherLen, 1);
kfree(src);
}
return retval;
This is a note to let you know that I have just added a patch titled crypto: aesni - fix memory usage in GCM decryption to the linux-3.16.y-queue branch of the 3.16.y-ckt extended stable tree which can be found at: http://kernel.ubuntu.com/git?p=ubuntu/linux.git;a=shortlog;h=refs/heads/linux-3.16.y-queue This patch is scheduled to be released in version 3.16.7-ckt10. If you, or anyone else, feels it should not be added to this tree, please reply to this email. For more information about the 3.16.y-ckt tree, see https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable Thanks. -Luis ------ From da3d3856b47cddbdc6b4d676bfaadd91c7571993 Mon Sep 17 00:00:00 2001 From: Stephan Mueller <smueller@chronox.de> Date: Thu, 12 Mar 2015 09:17:51 +0100 Subject: crypto: aesni - fix memory usage in GCM decryption commit ccfe8c3f7e52ae83155cb038753f4c75b774ca8a upstream. The kernel crypto API logic requires the caller to provide the length of (ciphertext || authentication tag) as cryptlen for the AEAD decryption operation. Thus, the cipher implementation must calculate the size of the plaintext output itself and cannot simply use cryptlen. The RFC4106 GCM decryption operation tries to overwrite cryptlen memory in req->dst. As the destination buffer for decryption only needs to hold the plaintext memory but cryptlen references the input buffer holding (ciphertext || authentication tag), the assumption of the destination buffer length in RFC4106 GCM operation leads to a too large size. This patch simply uses the already calculated plaintext size. In addition, this patch fixes the offset calculation of the AAD buffer pointer: as mentioned before, cryptlen already includes the size of the tag. Thus, the tag does not need to be added. With the addition, the AAD will be written beyond the already allocated buffer. Note, this fixes a kernel crash that can be triggered from user space via AF_ALG(aead) -- simply use the libkcapi test application from [1] and update it to use rfc4106-gcm-aes. Using [1], the changes were tested using CAVS vectors to demonstrate that the crypto operation still delivers the right results. [1] http://www.chronox.de/libkcapi.html CC: Tadeusz Struk <tadeusz.struk@intel.com> Signed-off-by: Stephan Mueller <smueller@chronox.de> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: Luis Henriques <luis.henriques@canonical.com> --- arch/x86/crypto/aesni-intel_glue.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)