crypto: af_alg - Forbid bind(2) when nokey child sockets are present

commit a6a48c565f6f112c6983e2a02b1602189ed6e26e upstream.

This patch forbids the calling of bind(2) when there are child
sockets created by accept(2) in existence, even if they are created
on the nokey path.

This is needed as those child sockets have references to the tfm
object which bind(2) will destroy.

Cc: stable@vger.kernel.org
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Andrey Ryabinin <aryabinin@virtuozzo.com>
Signed-off-by: Willy Tarreau <w@1wt.eu>
This commit is contained in:
Herbert Xu 2016-10-27 17:29:45 +03:00 committed by syphyr
parent 5adc99b9b6
commit 806541f7ba
1 changed files with 7 additions and 9 deletions

View File

@ -130,19 +130,16 @@ EXPORT_SYMBOL_GPL(af_alg_release);
void af_alg_release_parent(struct sock *sk)
{
struct alg_sock *ask = alg_sk(sk);
bool last;
unsigned int nokey = ask->nokey_refcnt;
bool last = nokey && !ask->refcnt;
sk = ask->parent;
if (ask->nokey_refcnt && !ask->refcnt) {
sock_put(sk);
return;
}
ask = alg_sk(sk);
lock_sock(sk);
last = !--ask->refcnt;
ask->nokey_refcnt -= nokey;
if (!last)
last = !--ask->refcnt;
release_sock(sk);
if (last)
@ -185,7 +182,7 @@ static int alg_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len)
err = -EBUSY;
lock_sock(sk);
if (ask->refcnt)
if (ask->refcnt | ask->nokey_refcnt)
goto unlock;
swap(ask->type, type);
@ -296,6 +293,7 @@ int af_alg_accept(struct sock *sk, struct socket *newsock)
if (nokey || !ask->refcnt++)
sock_hold(sk);
ask->nokey_refcnt += nokey;
alg_sk(sk2)->parent = sk;
alg_sk(sk2)->type = type;
alg_sk(sk2)->nokey_refcnt = nokey;