lkml.org 
[lkml]   [2021]   [Dec]   [6]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCH mptcp] mptcp: remove tcp ulp setsockopt support
On Sun,  5 Dec 2021 20:27:00 +0100 Florian Westphal wrote:
> TCP_ULP setsockopt cannot be used for mptcp because its already
> used internally to plumb subflow (tcp) sockets to the mptcp layer.
>
> syzbot managed to trigger a crash for mptcp connections that are
> in fallback mode:

Fallback mode meaning ops are NULL? I'm slightly confused by this
report.

> KASAN: null-ptr-deref in range [0x0000000000000020-0x0000000000000027]
> CPU: 1 PID: 1083 Comm: syz-executor.3 Not tainted 5.16.0-rc2-syzkaller #0
> RIP: 0010:tls_build_proto net/tls/tls_main.c:776 [inline]
> [..]
> __tcp_set_ulp net/ipv4/tcp_ulp.c:139 [inline]
> tcp_set_ulp+0x428/0x4c0 net/ipv4/tcp_ulp.c:160
> do_tcp_setsockopt+0x455/0x37c0 net/ipv4/tcp.c:3391
> mptcp_setsockopt+0x1b47/0x2400 net/mptcp/sockopt.c:638
>
> Remove support for TCP_ULP setsockopt.
>
> Reported-by: syzbot+1fd9b69cde42967d1add@syzkaller.appspotmail.com
> Signed-off-by: Florian Westphal <fw@strlen.de>

\
 
 \ /
  Last update: 2021-12-06 17:02    [W:0.059 / U:0.492 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site