path: root/net/l2tp/l2tp_ip6.c
diff options
authorEric Dumazet <edumazet@google.com>2016-10-20 09:39:40 -0700
committerDavid S. Miller <davem@davemloft.net>2016-10-20 14:45:52 -0400
commit286c72deabaa240b7eebbd99496ed3324d69f3c0 (patch)
tree00a0b07bfc20b08a025720c4c1b3c724ed4eaf67 /net/l2tp/l2tp_ip6.c
parentnet: dsa: bcm_sf2: Prevent GPHY shutdown for kexec'd kernels (diff)
udp: must lock the socket in udp_disconnect()
Baozeng Ding reported KASAN traces showing uses after free in udp_lib_get_port() and other related UDP functions. A CONFIG_DEBUG_PAGEALLOC=y kernel would eventually crash. I could write a reproducer with two threads doing : static int sock_fd; static void *thr1(void *arg) { for (;;) { connect(sock_fd, (const struct sockaddr *)arg, sizeof(struct sockaddr_in)); } } static void *thr2(void *arg) { struct sockaddr_in unspec; for (;;) { memset(&unspec, 0, sizeof(unspec)); connect(sock_fd, (const struct sockaddr *)&unspec, sizeof(unspec)); } } Problem is that udp_disconnect() could run without holding socket lock, and this was causing list corruptions. Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: Baozeng Ding <sploving1@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/l2tp/l2tp_ip6.c')
1 files changed, 1 insertions, 1 deletions
diff --git a/net/l2tp/l2tp_ip6.c b/net/l2tp/l2tp_ip6.c
index ea2ae6664cc8..ad3468c32b53 100644
--- a/net/l2tp/l2tp_ip6.c
+++ b/net/l2tp/l2tp_ip6.c
@@ -410,7 +410,7 @@ static int l2tp_ip6_disconnect(struct sock *sk, int flags)
if (sock_flag(sk, SOCK_ZAPPED))
return 0;
- return udp_disconnect(sk, flags);
+ return __udp_disconnect(sk, flags);
static int l2tp_ip6_getname(struct socket *sock, struct sockaddr *uaddr,