From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id EB44379DD; Sat, 30 Dec 2023 12:02:28 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="SBeg8SMg" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 73AAEC433C7; Sat, 30 Dec 2023 12:02:28 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1703937748; bh=94H8GIqt6TB+nnvTshVlUWE0sAAnDhzsPPUmUen6qrg=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=SBeg8SMgtGzds3etKLe9GHeCOl7Cs8gI5qOaSWi7fsqT59ZvvtU0+U4pkJDEpWepd 23DJYD2aSD/baMdxUItpEkVOdk5asLavhW+SLjKxrSakVptQH7QtsP10OD+C1xnu16 UaseStK4WMtaPVIOj8tihHGQuVr26tSepY8+6adQ= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Shigeru Yoshida , Kuniyuki Iwashima , syzbot+c71bc336c5061153b502@syzkaller.appspotmail.com, Eric Dumazet , syzbot , "David S. Miller" , Sasha Levin Subject: [PATCH 6.6 047/156] net: Return error from sk_stream_wait_connect() if sk_wait_event() fails Date: Sat, 30 Dec 2023 11:58:21 +0000 Message-ID: <20231230115813.887941227@linuxfoundation.org> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20231230115812.333117904@linuxfoundation.org> References: <20231230115812.333117904@linuxfoundation.org> User-Agent: quilt/0.67 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.6-stable review patch. If anyone has any objections, please let me know. ------------------ From: Shigeru Yoshida [ Upstream commit cac23b7d7627915d967ce25436d7aae26e88ed06 ] The following NULL pointer dereference issue occurred: BUG: kernel NULL pointer dereference, address: 0000000000000000 <...> RIP: 0010:ccid_hc_tx_send_packet net/dccp/ccid.h:166 [inline] RIP: 0010:dccp_write_xmit+0x49/0x140 net/dccp/output.c:356 <...> Call Trace: dccp_sendmsg+0x642/0x7e0 net/dccp/proto.c:801 inet_sendmsg+0x63/0x90 net/ipv4/af_inet.c:846 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg+0x83/0xe0 net/socket.c:745 ____sys_sendmsg+0x443/0x510 net/socket.c:2558 ___sys_sendmsg+0xe5/0x150 net/socket.c:2612 __sys_sendmsg+0xa6/0x120 net/socket.c:2641 __do_sys_sendmsg net/socket.c:2650 [inline] __se_sys_sendmsg net/socket.c:2648 [inline] __x64_sys_sendmsg+0x45/0x50 net/socket.c:2648 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x43/0x110 arch/x86/entry/common.c:82 entry_SYSCALL_64_after_hwframe+0x63/0x6b sk_wait_event() returns an error (-EPIPE) if disconnect() is called on the socket waiting for the event. However, sk_stream_wait_connect() returns success, i.e. zero, even if sk_wait_event() returns -EPIPE, so a function that waits for a connection with sk_stream_wait_connect() may misbehave. In the case of the above DCCP issue, dccp_sendmsg() is waiting for the connection. If disconnect() is called in concurrently, the above issue occurs. This patch fixes the issue by returning error from sk_stream_wait_connect() if sk_wait_event() fails. Fixes: 419ce133ab92 ("tcp: allow again tcp_disconnect() when threads are waiting") Signed-off-by: Shigeru Yoshida Reviewed-by: Kuniyuki Iwashima Reported-by: syzbot+c71bc336c5061153b502@syzkaller.appspotmail.com Reviewed-by: Eric Dumazet Reported-by: syzbot Reported-by: syzkaller Signed-off-by: David S. Miller Signed-off-by: Sasha Levin --- net/core/stream.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/net/core/stream.c b/net/core/stream.c index 96fbcb9bbb30a..b16dfa568a2d5 100644 --- a/net/core/stream.c +++ b/net/core/stream.c @@ -79,7 +79,7 @@ int sk_stream_wait_connect(struct sock *sk, long *timeo_p) remove_wait_queue(sk_sleep(sk), &wait); sk->sk_write_pending--; } while (!done); - return 0; + return done < 0 ? done : 0; } EXPORT_SYMBOL(sk_stream_wait_connect); -- 2.43.0