This is a note to let you know that I've just added the patch titled
tcp: Fix use-after-free of nreq in reqsk_timer_handler().
to the 5.15-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:
tcp-fix-use-after-free-of-nreq-in-reqsk_timer_handle.patch
and it can be found in the queue-5.15 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit e97767f81ce70f2fd92c93c175016a5e3855d062
Author: Kuniyuki Iwashima <kuniyu@xxxxxxxxxx>
Date: Sat Nov 23 09:42:36 2024 -0800
tcp: Fix use-after-free of nreq in reqsk_timer_handler().
[ Upstream commit c31e72d021db2714df03df6c42855a1db592716c ]
The cited commit replaced inet_csk_reqsk_queue_drop_and_put() with
__inet_csk_reqsk_queue_drop() and reqsk_put() in reqsk_timer_handler().
Then, oreq should be passed to reqsk_put() instead of req; otherwise
use-after-free of nreq could happen when reqsk is migrated but the
retry attempt failed (e.g. due to timeout).
Let's pass oreq to reqsk_put().
Fixes: e8c526f2bdf1 ("tcp/dccp: Don't use timer_pending() in reqsk_queue_unlink().")
Reported-by: Liu Jian <liujian56@xxxxxxxxxx>
Closes: https://lore.kernel.org/netdev/1284490f-9525-42ee-b7b8-ccadf6606f6d@xxxxxxxxxx/
Signed-off-by: Kuniyuki Iwashima <kuniyu@xxxxxxxxxx>
Reviewed-by: Vadim Fedorenko <vadim.fedorenko@xxxxxxxxx>
Reviewed-by: Liu Jian <liujian56@xxxxxxxxxx>
Reviewed-by: Eric Dumazet <edumazet@xxxxxxxxxx>
Reviewed-by: Martin KaFai Lau <martin.lau@xxxxxxxxxx>
Link: https://patch.msgid.link/20241123174236.62438-1-kuniyu@xxxxxxxxxx
Signed-off-by: Paolo Abeni <pabeni@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/net/ipv4/inet_connection_sock.c b/net/ipv4/inet_connection_sock.c
index 63e5aa6d4b0bc..73ef8b4f57049 100644
--- a/net/ipv4/inet_connection_sock.c
+++ b/net/ipv4/inet_connection_sock.c
@@ -935,7 +935,7 @@ static void reqsk_timer_handler(struct timer_list *t)
drop:
__inet_csk_reqsk_queue_drop(sk_listener, oreq, true);
- reqsk_put(req);
+ reqsk_put(oreq);
}
static bool reqsk_queue_hash_req(struct request_sock *req,
