This is a note to let you know that I've just added the patch titled crypto: af_alg - whitelist mask and type to the 4.9-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-whitelist-mask-and-type.patch and it can be found in the queue-4.9 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From bb30b8848c85e18ca7e371d0a869e94b3e383bdf Mon Sep 17 00:00:00 2001 From: Stephan Mueller <smueller@xxxxxxxxxx> Date: Tue, 2 Jan 2018 08:55:25 +0100 Subject: crypto: af_alg - whitelist mask and type From: Stephan Mueller <smueller@xxxxxxxxxx> commit bb30b8848c85e18ca7e371d0a869e94b3e383bdf upstream. The user space interface allows specifying the type and mask field used to allocate the cipher. Only a subset of the possible flags are intended for user space. Therefore, white-list the allowed flags. In case the user space caller uses at least one non-allowed flag, EINVAL is returned. Reported-by: syzbot <syzkaller@xxxxxxxxxxxxxxxx> Signed-off-by: Stephan Mueller <smueller@xxxxxxxxxx> Signed-off-by: Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- crypto/af_alg.c | 10 ++++++---- 1 file changed, 6 insertions(+), 4 deletions(-) --- a/crypto/af_alg.c +++ b/crypto/af_alg.c @@ -149,7 +149,7 @@ EXPORT_SYMBOL_GPL(af_alg_release_parent) static int alg_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len) { - const u32 forbidden = CRYPTO_ALG_INTERNAL; + const u32 allowed = CRYPTO_ALG_KERN_DRIVER_ONLY; struct sock *sk = sock->sk; struct alg_sock *ask = alg_sk(sk); struct sockaddr_alg *sa = (void *)uaddr; @@ -157,6 +157,10 @@ static int alg_bind(struct socket *sock, void *private; int err; + /* If caller uses non-allowed flag, return error. */ + if ((sa->salg_feat & ~allowed) || (sa->salg_mask & ~allowed)) + return -EINVAL; + if (sock->state == SS_CONNECTED) return -EINVAL; @@ -175,9 +179,7 @@ static int alg_bind(struct socket *sock, if (IS_ERR(type)) return PTR_ERR(type); - private = type->bind(sa->salg_name, - sa->salg_feat & ~forbidden, - sa->salg_mask & ~forbidden); + private = type->bind(sa->salg_name, sa->salg_feat, sa->salg_mask); if (IS_ERR(private)) { module_put(type->owner); return PTR_ERR(private); Patches currently in stable-queue which might be from smueller@xxxxxxxxxx are queue-4.9/crypto-af_alg-whitelist-mask-and-type.patch queue-4.9/crypto-aesni-handle-zero-length-dst-buffer.patch