38 lines
1.3 KiB
Diff
38 lines
1.3 KiB
Diff
From: Eric Dumazet <edumazet@google.com>
|
|
Date: Tue, 9 May 2017 06:29:19 -0700
|
|
Subject: dccp/tcp: do not inherit mc_list from parent
|
|
Origin: https://git.kernel.org/linus/657831ffc38e30092a2d5f03d385d710eb88b09a
|
|
Bug-Debian-Security: https://security-tracker.debian.org/tracker/CVE-2017-8890
|
|
|
|
syzkaller found a way to trigger double frees from ip_mc_drop_socket()
|
|
|
|
It turns out that leave a copy of parent mc_list at accept() time,
|
|
which is very bad.
|
|
|
|
Very similar to commit 8b485ce69876 ("tcp: do not inherit
|
|
fastopen_req from parent")
|
|
|
|
Initial report from Pray3r, completed by Andrey one.
|
|
Thanks a lot to them !
|
|
|
|
Signed-off-by: Eric Dumazet <edumazet@google.com>
|
|
Reported-by: Pray3r <pray3r.z@gmail.com>
|
|
Reported-by: Andrey Konovalov <andreyknvl@google.com>
|
|
Tested-by: Andrey Konovalov <andreyknvl@google.com>
|
|
Signed-off-by: David S. Miller <davem@davemloft.net>
|
|
---
|
|
net/ipv4/inet_connection_sock.c | 2 ++
|
|
1 file changed, 2 insertions(+)
|
|
|
|
--- a/net/ipv4/inet_connection_sock.c
|
|
+++ b/net/ipv4/inet_connection_sock.c
|
|
@@ -665,6 +665,8 @@ struct sock *inet_csk_clone_lock(const s
|
|
/* listeners have SOCK_RCU_FREE, not the children */
|
|
sock_reset_flag(newsk, SOCK_RCU_FREE);
|
|
|
|
+ inet_sk(newsk)->mc_list = NULL;
|
|
+
|
|
newsk->sk_mark = inet_rsk(req)->ir_mark;
|
|
atomic64_set(&newsk->sk_cookie,
|
|
atomic64_read(&inet_rsk(req)->ir_cookie));
|