path: root/crypto
diff options
authorStephan Mueller <smueller@chronox.de>2018-01-02 08:55:25 +0100
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2018-02-03 17:58:33 +0100
commitcc5daa4b691b70b2e2f1e815926196449435273a (patch)
tree3e6bea09afe441c28f6c8c88d4d2057d3805bd92 /crypto
parent66ae99ca89cb3f22ffff81084ce5446d0122abdb (diff)
crypto: af_alg - whitelist mask and type
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@googlegroups.com> Signed-off-by: Stephan Mueller <smueller@chronox.de> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'crypto')
1 files changed, 6 insertions, 4 deletions
diff --git a/crypto/af_alg.c b/crypto/af_alg.c
index 35d4dcea381f..5231f421ad00 100644
--- a/crypto/af_alg.c
+++ b/crypto/af_alg.c
@@ -150,7 +150,7 @@ 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;
@@ -158,6 +158,10 @@ static int alg_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len)
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;
@@ -176,9 +180,7 @@ static int alg_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len)
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)) {
return PTR_ERR(private);