linux/net/smc
D. Wythe 9f1c50cf39 net/smc: fix connection leak
There's a potential leak issue under following execution sequence :

smc_release  				smc_connect_work
if (sk->sk_state == SMC_INIT)
					send_clc_confirim
	tcp_abort();
					...
					sk.sk_state = SMC_ACTIVE
smc_close_active
switch(sk->sk_state) {
...
case SMC_ACTIVE:
	smc_close_final()
	// then wait peer closed

Unfortunately, tcp_abort() may discard CLC CONFIRM messages that are
still in the tcp send buffer, in which case our connection token cannot
be delivered to the server side, which means that we cannot get a
passive close message at all. Therefore, it is impossible for the to be
disconnected at all.

This patch tries a very simple way to avoid this issue, once the state
has changed to SMC_ACTIVE after tcp_abort(), we can actively abort the
smc connection, considering that the state is SMC_INIT before
tcp_abort(), abandoning the complete disconnection process should not
cause too much problem.

In fact, this problem may exist as long as the CLC CONFIRM message is
not received by the server. Whether a timer should be added after
smc_close_final() needs to be discussed in the future. But even so, this
patch provides a faster release for connection in above case, it should
also be valuable.

Fixes: 39f41f367b ("net/smc: common release code for non-accepted sockets")
Signed-off-by: D. Wythe <alibuda@linux.alibaba.com>
Acked-by: Karsten Graul <kgraul@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-02-25 10:40:21 +00:00
..
af_smc.c net/smc: fix connection leak 2022-02-25 10:40:21 +00:00
Kconfig treewide: replace '---help---' in Kconfig files with 'help' 2020-06-14 01:57:21 +09:00
Makefile net/smc: Introduce tracepoint for fallback 2021-11-01 13:39:14 +00:00
smc_cdc.c net/smc: Introduce a new conn->lgr validity check helper 2022-01-13 13:14:53 +00:00
smc_cdc.h net/smc: fix kernel panic caused by race of smc_sock 2021-12-28 12:42:45 +00:00
smc_clc.c net/smc: Introduce a new conn->lgr validity check helper 2022-01-13 13:14:53 +00:00
smc_clc.h net/smc: add v2 format of CLC decline message 2021-10-16 14:58:13 +01:00
smc_close.c net/smc: Keep smc_close_final rc during active close 2021-12-02 12:14:36 +00:00
smc_close.h net/smc: remove close abort worker 2019-10-22 11:23:44 -07:00
smc_core.c net/smc: Fix hung_task when removing SMC-R devices 2022-01-16 12:30:28 +00:00
smc_core.h net/smc: Resolve the race between SMC-R link access and clear 2022-01-13 13:14:53 +00:00
smc_diag.c Partially revert "net/smc: Add netlink net namespace support" 2022-02-02 07:42:41 -08:00
smc_ib.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next 2021-12-31 14:35:40 +00:00
smc_ib.h net/smc: Introduce net namespace support for linkgroup 2022-01-02 12:07:39 +00:00
smc_ism.c net: Don't include filter.h from net/sock.h 2021-12-29 08:48:14 -08:00
smc_ism.h net/smc: keep static copy of system EID 2021-09-14 12:49:10 +01:00
smc_llc.c net/smc: Print net namespace in log 2022-01-02 12:07:39 +00:00
smc_llc.h net/smc: extend LLC layer for SMC-Rv2 2021-10-16 14:58:13 +01:00
smc_netlink.c net/smc: add generic netlink support for system EID 2021-09-14 12:49:10 +01:00
smc_netlink.h net/smc: add support for user defined EIDs 2021-09-14 12:49:10 +01:00
smc_netns.h net/smc: introduce list of pnetids for Ethernet devices 2020-09-28 15:19:03 -07:00
smc_pnet.c net/smc: Use a mutex for locking "struct smc_pnettable" 2022-02-24 09:09:33 -08:00
smc_pnet.h net/smc: Use a mutex for locking "struct smc_pnettable" 2022-02-24 09:09:33 -08:00
smc_rx.c net/smc: Introduce tracepoints for tx and rx msg 2021-11-01 13:39:14 +00:00
smc_rx.h smc: add support for splice() 2018-05-04 11:45:06 -04:00
smc_stats.c net/smc: Fix ENODATA tests in smc_nl_get_fback_stats() 2021-06-21 12:16:58 -07:00
smc_stats.h net/smc: Make SMC statistics network namespace aware 2021-06-16 12:54:02 -07:00
smc_tracepoint.c net/smc: Introduce tracepoint for smcr link down 2021-11-01 13:39:14 +00:00
smc_tracepoint.h net/smc: Add net namespace for tracepoints 2022-01-02 12:07:39 +00:00
smc_tx.c net/smc: Introduce tracepoints for tx and rx msg 2021-11-01 13:39:14 +00:00
smc_tx.h net/smc: eliminate cursor read and write calls 2018-07-23 10:57:14 -07:00
smc_wr.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2021-12-30 12:12:12 -08:00
smc_wr.h net/smc: Remove unused function declaration 2022-01-15 22:57:21 +00:00
smc.h net/smc: Forward wakeup to smc socket waitqueue after fallback 2022-01-31 11:07:13 +00:00