This is a note to let you know that I've just added the patch titled crypto: algif_skcipher - Do not dereference ctx without socket lock to the 4.4-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-algif_skcipher-do-not-dereference-ctx-without-socket-lock.patch and it can be found in the queue-4.4 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From 6454c2b83f719057069777132b13949e4c6b6350 Mon Sep 17 00:00:00 2001 From: Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxx> Date: Wed, 3 Feb 2016 21:39:26 +0800 Subject: crypto: algif_skcipher - Do not dereference ctx without socket lock From: Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxx> commit 6454c2b83f719057069777132b13949e4c6b6350 upstream. Any access to non-constant bits of the private context must be done under the socket lock, in particular, this includes ctx->req. This patch moves such accesses under the lock, and fetches the tfm from the parent socket which is guaranteed to be constant, rather than from ctx->req. Signed-off-by: Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- crypto/algif_skcipher.c | 15 +++++++++++---- 1 file changed, 11 insertions(+), 4 deletions(-) --- a/crypto/algif_skcipher.c +++ b/crypto/algif_skcipher.c @@ -295,8 +295,11 @@ static int skcipher_sendmsg(struct socke { struct sock *sk = sock->sk; struct alg_sock *ask = alg_sk(sk); + struct sock *psk = ask->parent; + struct alg_sock *pask = alg_sk(psk); struct skcipher_ctx *ctx = ask->private; - struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(&ctx->req); + struct skcipher_tfm *skc = pask->private; + struct crypto_skcipher *tfm = skc->skcipher; unsigned ivsize = crypto_skcipher_ivsize(tfm); struct skcipher_sg_list *sgl; struct af_alg_control con = {}; @@ -508,7 +511,7 @@ static int skcipher_recvmsg_async(struct struct skcipher_async_req *sreq; struct skcipher_request *req; struct skcipher_async_rsgl *last_rsgl = NULL; - unsigned int txbufs = 0, len = 0, tx_nents = skcipher_all_sg_nents(ctx); + unsigned int txbufs = 0, len = 0, tx_nents; unsigned int reqsize = crypto_skcipher_reqsize(tfm); unsigned int ivsize = crypto_skcipher_ivsize(tfm); int err = -ENOMEM; @@ -526,6 +529,7 @@ static int skcipher_recvmsg_async(struct sreq->inflight = &ctx->inflight; lock_sock(sk); + tx_nents = skcipher_all_sg_nents(ctx); sreq->tsg = kcalloc(tx_nents, sizeof(*sg), GFP_KERNEL); if (unlikely(!sreq->tsg)) goto unlock; @@ -633,9 +637,12 @@ static int skcipher_recvmsg_sync(struct { struct sock *sk = sock->sk; struct alg_sock *ask = alg_sk(sk); + struct sock *psk = ask->parent; + struct alg_sock *pask = alg_sk(psk); struct skcipher_ctx *ctx = ask->private; - unsigned bs = crypto_skcipher_blocksize(crypto_skcipher_reqtfm( - &ctx->req)); + struct skcipher_tfm *skc = pask->private; + struct crypto_skcipher *tfm = skc->skcipher; + unsigned bs = crypto_skcipher_blocksize(tfm); struct skcipher_sg_list *sgl; struct scatterlist *sg; int err = -EAGAIN; Patches currently in stable-queue which might be from herbert@xxxxxxxxxxxxxxxxxxx are queue-4.4/crypto-af_alg-disallow-bind-setkey-...-after-accept-2.patch queue-4.4/crypto-crc32c-fix-crc32c-soft-dependency.patch queue-4.4/crypto-af_alg-forbid-bind-2-when-nokey-child-sockets-are-present.patch queue-4.4/crypto-algif_hash-fix-race-condition-in-hash_check_key.patch queue-4.4/crypto-skcipher-add-crypto_skcipher_has_setkey.patch queue-4.4/crypto-atmel-sha-remove-calls-of-clk_prepare-from-atomic-contexts.patch queue-4.4/crypto-chacha20-ssse3-align-stack-pointer-to-64-bytes.patch queue-4.4/crypto-algif_skcipher-add-key-check-exception-for-cipher_null.patch queue-4.4/crypto-algif_skcipher-do-not-assume-that-req-is-unchanged.patch queue-4.4/crypto-algif_hash-remove-custom-release-parent-function.patch queue-4.4/crypto-algif_skcipher-load-tx-sg-list-after-waiting.patch queue-4.4/crypto-algif_skcipher-require-setkey-before-accept-2.patch queue-4.4/crypto-user-lock-crypto_alg_list-on-alg-dump.patch queue-4.4/crypto-atmel-sha-fix-atmel_sha_remove.patch queue-4.4/crypto-marvell-cesa-fix-test-in-mv_cesa_dev_dma_init.patch queue-4.4/crypto-algif_skcipher-add-nokey-compatibility-path.patch queue-4.4/crypto-shash-fix-has_key-setting.patch queue-4.4/crypto-algif_skcipher-do-not-dereference-ctx-without-socket-lock.patch queue-4.4/crypto-algif_skcipher-remove-custom-release-parent-function.patch queue-4.4/crypto-af_alg-allow-af_af_alg_release_parent-to-be-called-on-nokey-path.patch queue-4.4/crypto-hash-add-crypto_ahash_has_setkey.patch queue-4.4/crypto-af_alg-add-nokey-compatibility-path.patch queue-4.4/crypto-algif_skcipher-do-not-set-may_backlog-on-the-async-path.patch queue-4.4/crypto-sun4i-ss-add-missing-statesize.patch queue-4.4/crypto-algif_hash-require-setkey-before-accept-2.patch queue-4.4/crypto-algif_skcipher-sendmsg-sg-marking-is-off-by-one.patch queue-4.4/crypto-algif_skcipher-fix-race-condition-in-skcipher_check_key.patch queue-4.4/crypto-algif_hash-wait-for-crypto_ahash_init-to-complete.patch queue-4.4/crypto-caam-make-write-transactions-bufferable-on-ppc-platforms.patch queue-4.4/crypto-af_alg-fix-socket-double-free-when-accept-fails.patch -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html