sock_init_data() attaches the allocated sk pointer to the provided sock
object. If inet6_create() fails later, the sk object is released, but the
sock object retains the dangling sk pointer, which may cause use-after-free
later.
Clear the sock sk pointer on error.
Signed-off-by: Ignat Korchagin <ignat@cloudflare.com>
---
net/ipv6/af_inet6.c | 22 ++++++++++------------
1 file changed, 10 insertions(+), 12 deletions(-)
diff --git a/net/ipv6/af_inet6.c b/net/ipv6/af_inet6.c
index ba69b86f1c7d..f60ec8b0f8ea 100644
--- a/net/ipv6/af_inet6.c
+++ b/net/ipv6/af_inet6.c
@@ -252,31 +252,29 @@ static int inet6_create(struct net *net, struct socket *sock, int protocol,
*/
inet->inet_sport = htons(inet->inet_num);
err = sk->sk_prot->hash(sk);
- if (err) {
- sk_common_release(sk);
- goto out;
- }
+ if (err)
+ goto out_sk_release;
}
if (sk->sk_prot->init) {
err = sk->sk_prot->init(sk);
- if (err) {
- sk_common_release(sk);
- goto out;
- }
+ if (err)
+ goto out_sk_release;
}
if (!kern) {
err = BPF_CGROUP_RUN_PROG_INET_SOCK(sk);
- if (err) {
- sk_common_release(sk);
- goto out;
- }
+ if (err)
+ goto out_sk_release;
}
out:
return err;
out_rcu_unlock:
rcu_read_unlock();
goto out;
+out_sk_release:
+ sk_common_release(sk);
+ sock->sk = NULL;
+ goto out;
}
static int __inet6_bind(struct sock *sk, struct sockaddr *uaddr, int addr_len,
--
2.39.5