This is a note to let you know that I've just added the patch titled
Bluetooth: RFCOMM: avoid leaving dangling sk pointer in rfcomm_sock_alloc()
to the 6.1-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
bluetooth-rfcomm-avoid-leaving-dangling-sk-pointer-i.patch
and it can be found in the queue-6.1 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit 2c15b739ef48c89ebdfe226a625781409f36a5d4
Author: Ignat Korchagin <ignat@xxxxxxxxxxxxxx>
Date: Mon Oct 14 16:38:02 2024 +0100
Bluetooth: RFCOMM: avoid leaving dangling sk pointer in rfcomm_sock_alloc()
[ Upstream commit 3945c799f12b8d1f49a3b48369ca494d981ac465 ]
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@xxxxxxxxxxxxxx>
Reviewed-by: Kuniyuki Iwashima <kuniyu@xxxxxxxxxx>
Reviewed-by: Eric Dumazet <edumazet@xxxxxxxxxx>
Link: https://patch.msgid.link/20241014153808.51894-4-ignat@xxxxxxxxxxxxxx
Signed-off-by: Jakub Kicinski <kuba@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/net/bluetooth/rfcomm/sock.c b/net/bluetooth/rfcomm/sock.c
index 4fae82fedccaf..1cf6543bdec55 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;
}
