diff options
| author | Herbert Xu <herbert@gondor.apana.org.au> | 2016-01-15 17:01:08 +0300 |
|---|---|---|
| committer | Sasha Levin <sasha.levin@oracle.com> | 2016-02-10 06:57:34 +0300 |
| commit | 2b12ef1b9ee70d1764532455ff85ca7f041e31c3 (patch) | |
| tree | 189ad0868a917659d653c426808ae5517903a6f6 /crypto | |
| parent | bcfa84116d4c1baa69f961d5e107849217868e31 (diff) | |
| download | linux-2b12ef1b9ee70d1764532455ff85ca7f041e31c3.tar.xz | |
crypto: algif_hash - Fix race condition in hash_check_key
[ Upstream commit ad46d7e33219218605ea619e32553daf4f346b9f ]
We need to lock the child socket in hash_check_key as otherwise
two simultaneous calls can cause the parent socket to be freed.
Cc: stable@vger.kernel.org
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
Diffstat (limited to 'crypto')
| -rw-r--r-- | crypto/algif_hash.c | 9 |
1 files changed, 6 insertions, 3 deletions
diff --git a/crypto/algif_hash.c b/crypto/algif_hash.c index 20550b1b4fef..c92b7f67f377 100644 --- a/crypto/algif_hash.c +++ b/crypto/algif_hash.c @@ -245,22 +245,23 @@ 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; @@ -274,6 +275,8 @@ static int hash_check_key(struct socket *sock) unlock: release_sock(psk); +unlock_child: + release_sock(sk); return err; } |