[PATCH 4.17 40/63] net: diag: Dont double-free TCP_NEW_SYN_RECV sockets in tcp_abort
From: Greg Kroah-Hartman
Date: Mon Jul 23 2018 - 08:27:06 EST
4.17-stable review patch. If anyone has any objections, please let me know.
------------------
From: Lorenzo Colitti <lorenzo@xxxxxxxxxx>
[ Upstream commit acc2cf4e37174646a24cba42fa53c668b2338d4e ]
When tcp_diag_destroy closes a TCP_NEW_SYN_RECV socket, it first
frees it by calling inet_csk_reqsk_queue_drop_and_and_put in
tcp_abort, and then frees it again by calling sock_gen_put.
Since tcp_abort only has one caller, and all the other codepaths
in tcp_abort don't free the socket, just remove the free in that
function.
Cc: David Ahern <dsa@xxxxxxxxxxxxxxxxxxx>
Tested: passes Android sock_diag_test.py, which exercises this codepath
Fixes: d7226c7a4dd1 ("net: diag: Fix refcnt leak in error path destroying socket")
Signed-off-by: Lorenzo Colitti <lorenzo@xxxxxxxxxx>
Signed-off-by: Eric Dumazet <edumazet@xxxxxxxxxx>
Reviewed-by: David Ahern <dsa@xxxxxxxxxxxxxxxxxxx>
Tested-by: David Ahern <dsa@xxxxxxxxxxxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
net/ipv4/tcp.c | 3 +--
1 file changed, 1 insertion(+), 2 deletions(-)
--- a/net/ipv4/tcp.c
+++ b/net/ipv4/tcp.c
@@ -3524,8 +3524,7 @@ int tcp_abort(struct sock *sk, int err)
struct request_sock *req = inet_reqsk(sk);
local_bh_disable();
- inet_csk_reqsk_queue_drop_and_put(req->rsk_listener,
- req);
+ inet_csk_reqsk_queue_drop(req->rsk_listener, req);
local_bh_enable();
return 0;
}