crypto: af_alg - Forbid bind(2) when nokey child sockets are present
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>
diff --git a/crypto/af_alg.c b/crypto/af_alg.c
index e7cb836..f5e18c2 100644
--- a/crypto/af_alg.c
+++ b/crypto/af_alg.c
@@ -130,19 +130,16 @@
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)
@@ -188,7 +185,7 @@
err = -EBUSY;
lock_sock(sk);
- if (ask->refcnt)
+ if (ask->refcnt | ask->nokey_refcnt)
goto unlock;
swap(ask->type, type);
@@ -306,6 +303,7 @@
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;