This is a note to let you know that I've just added the patch titled crypto: algif_hash - Fix race condition in hash_check_key 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_hash-fix-race-condition-in-hash_check_key.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 ad46d7e33219218605ea619e32553daf4f346b9f Mon Sep 17 00:00:00 2001 From: Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxx> Date: Fri, 15 Jan 2016 22:01:08 +0800 Subject: crypto: algif_hash - Fix race condition in hash_check_key From: Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxx> commit ad46d7e33219218605ea619e32553daf4f346b9f upstream. We need to lock the child socket in hash_check_key as otherwise two simultaneous calls can cause the parent socket to be freed. Signed-off-by: Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- crypto/algif_hash.c | 9 ++++++--- 1 file changed, 6 insertions(+), 3 deletions(-) --- a/crypto/algif_hash.c +++ b/crypto/algif_hash.c @@ -242,22 +242,23 @@ static struct proto_ops algif_hash_ops = static int hash_check_key(struct socket *sock) { - int err; + int err = 0; struct sock *psk; struct alg_sock *pask; struct algif_hash_tfm *tfm; struct sock *sk = sock->sk; struct alg_sock *ask = alg_sk(sk); + lock_sock(sk); if (ask->refcnt) - return 0; + goto unlock_child; psk = ask->parent; pask = alg_sk(ask->parent); tfm = pask->private; err = -ENOKEY; - lock_sock(psk); + lock_sock_nested(psk, SINGLE_DEPTH_NESTING); if (!tfm->has_key) goto unlock; @@ -271,6 +272,8 @@ static int hash_check_key(struct socket unlock: release_sock(psk); +unlock_child: + release_sock(sk); return err; } 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-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_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-algif_skcipher-add-nokey-compatibility-path.patch queue-4.4/crypto-shash-fix-has_key-setting.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-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-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