diff mbox series

[v2,4/8] Bluetooth: RFCOMM: avoid leaving dangling sk pointer in rfcomm_sock_alloc()

Message ID 20241007213502.28183-5-ignat@cloudflare.com
State Accepted
Commit 3945c799f12b8d1f49a3b48369ca494d981ac465
Headers show
Series do not leave dangling sk pointers in pf->create functions | expand

Commit Message

Ignat Korchagin Oct. 7, 2024, 9:34 p.m. UTC 
bt_sock_alloc() attaches allocated sk object to the provided sock object.
If rfcomm_dlc_alloc() fails, we release the sk object, but leave the
dangling pointer in the sock object, which may cause use-after-free.

Fix this by swapping calls to bt_sock_alloc() and rfcomm_dlc_alloc().

Signed-off-by: Ignat Korchagin <ignat@cloudflare.com>
---
 net/bluetooth/rfcomm/sock.c | 10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)
diff mbox series

Patch

diff --git a/net/bluetooth/rfcomm/sock.c b/net/bluetooth/rfcomm/sock.c
index 37d63d768afb..0d0c4311da57 100644
--- a/net/bluetooth/rfcomm/sock.c
+++ b/net/bluetooth/rfcomm/sock.c
@@ -274,13 +274,13 @@  static struct sock *rfcomm_sock_alloc(struct net *net, struct socket *sock,
 	struct rfcomm_dlc *d;
 	struct sock *sk;
 
-	sk = bt_sock_alloc(net, sock, &rfcomm_proto, proto, prio, kern);
-	if (!sk)
+	d = rfcomm_dlc_alloc(prio);
+	if (!d)
 		return NULL;
 
-	d = rfcomm_dlc_alloc(prio);
-	if (!d) {
-		sk_free(sk);
+	sk = bt_sock_alloc(net, sock, &rfcomm_proto, proto, prio, kern);
+	if (!sk) {
+		rfcomm_dlc_free(d);
 		return NULL;
 	}