Maxim Galaganov 23311b9275 mptcp: fix deadlock in __mptcp_push_pending() ... [ Upstream commit 3d79e3756c ] __mptcp_push_pending() may call mptcp_flush_join_list() with subflow socket lock held. If such call hits mptcp_sockopt_sync_all() then subsequently __mptcp_sockopt_sync() could try to lock the subflow socket for itself, causing a deadlock. sysrq: Show Blocked State task:ss-server state:D stack: 0 pid: 938 ppid: 1 flags:0x00000000 Call Trace: <TASK> __schedule+0x2d6/0x10c0 ? __mod_memcg_state+0x4d/0x70 ? csum_partial+0xd/0x20 ? _raw_spin_lock_irqsave+0x26/0x50 schedule+0x4e/0xc0 __lock_sock+0x69/0x90 ? do_wait_intr_irq+0xa0/0xa0 __lock_sock_fast+0x35/0x50 mptcp_sockopt_sync_all+0x38/0xc0 __mptcp_push_pending+0x105/0x200 mptcp_sendmsg+0x466/0x490 sock_sendmsg+0x57/0x60 __sys_sendto+0xf0/0x160 ? do_wait_intr_irq+0xa0/0xa0 ? fpregs_restore_userregs+0x12/0xd0 __x64_sys_sendto+0x20/0x30 do_syscall_64+0x38/0x90 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7f9ba546c2d0 RSP: 002b:00007ffdc3b762d8 EFLAGS: 00000246 ORIG_RAX: 000000000000002c RAX: ffffffffffffffda RBX: 00007f9ba56c8060 RCX: 00007f9ba546c2d0 RDX: 000000000000077a RSI: 0000000000e5e180 RDI: 0000000000000234 RBP: 0000000000cc57f0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f9ba56c8060 R13: 0000000000b6ba60 R14: 0000000000cc7840 R15: 41d8685b1d7901b8 </TASK> Fix the issue by using __mptcp_flush_join_list() instead of plain mptcp_flush_join_list() inside __mptcp_push_pending(), as suggested by Florian. The sockopt sync will be deferred to the workqueue. Fixes: 1b3e7ede13 ("mptcp: setsockopt: handle SO_KEEPALIVE and SO_PRIORITY") Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/244 Suggested-by: Florian Westphal <fw@strlen.de> Reviewed-by: Florian Westphal <fw@strlen.de> Signed-off-by: Maxim Galaganov <max@internet.ru> Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>		2021-12-22 09:32:43 +01:00
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Kconfig	kunit: mptcp: adhere to KUNIT formatting standard	2021-04-16 17:10:40 -07:00
Makefile	kunit: mptcp: adhere to KUNIT formatting standard	2021-04-16 17:10:40 -07:00
crypto.c	kunit: mptcp: adhere to KUNIT formatting standard	2021-04-16 17:10:40 -07:00
crypto_test.c	mptcp: move crypto test to KUNIT	2020-06-26 16:21:39 -07:00
ctrl.c	mptcp: faster active backup recovery	2021-08-14 11:37:25 +01:00
diag.c	mptcp: allow dumping subflow context to userspace	2020-03-29 22:14:48 -07:00
mib.c	mptcp: add the mibs for MP_FAIL	2021-08-25 11:02:35 +01:00
mib.h	mptcp: add the mibs for MP_FAIL	2021-08-25 11:02:35 +01:00
mptcp_diag.c	mptcp: don't return sockets in foreign netns	2021-09-24 10:51:36 +01:00
options.c	mptcp: use delegate action to schedule 3rd ack retrans	2021-12-01 09:04:49 +01:00
pm.c	mptcp: MP_FAIL suboption receiving	2021-08-25 11:02:34 +01:00
pm_netlink.c	mptcp: never allow the PM to close a listener subflow	2021-12-22 09:32:41 +01:00
protocol.c	mptcp: fix deadlock in __mptcp_push_pending()	2021-12-22 09:32:43 +01:00
protocol.h	mptcp: use delegate action to schedule 3rd ack retrans	2021-12-01 09:04:49 +01:00
sockopt.c	mptcp: remove tcp ulp setsockopt support	2021-12-22 09:32:43 +01:00
subflow.c	mptcp: don't return sockets in foreign netns	2021-09-24 10:51:36 +01:00
syncookies.c	mptcp: don't return sockets in foreign netns	2021-09-24 10:51:36 +01:00
token.c	mptcp: don't return sockets in foreign netns	2021-09-24 10:51:36 +01:00
token_test.c	mptcp: don't return sockets in foreign netns	2021-09-24 10:51:36 +01:00