Duoming Zhou 5c9422e2d8 mISDN: fix use-after-free bugs in l1oip timer handlers ... [ Upstream commit 2568a7e083 ] The l1oip_cleanup() traverses the l1oip_ilist and calls release_card() to cleanup module and stack. However, release_card() calls del_timer() to delete the timers such as keep_tl and timeout_tl. If the timer handler is running, the del_timer() will not stop it and result in UAF bugs. One of the processes is shown below: (cleanup routine) | (timer handler) release_card() | l1oip_timeout() ... | del_timer() | ... ... | kfree(hc) //FREE | | hc->timeout_on = 0 //USE Fix by calling del_timer_sync() in release_card(), which makes sure the timer handlers have finished before the resources, such as l1oip and so on, have been deallocated. What's more, the hc->workq and hc->socket_thread can kick those timers right back in. We add a bool flag to show if card is released. Then, check this flag in hc->workq and hc->socket_thread. Fixes: 3712b42d4b ("Add layer1 over IP support") Signed-off-by: Duoming Zhou <duoming@zju.edu.cn> Reviewed-by: Leon Romanovsky <leonro@nvidia.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Sasha Levin <sashal@kernel.org>		2022-10-21 12:38:19 +02:00
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capi	isdn: cpai: no need to initialise statics to 0	2021-12-13 14:05:00 +00:00
hardware	isdn: mISDN: hfcsusb: drop unexpected word "the" in the comments	2022-06-22 18:20:46 -07:00
mISDN	mISDN: fix use-after-free bugs in l1oip timer handlers	2022-10-21 12:38:19 +02:00
Kconfig	treewide: replace '---help---' in Kconfig files with 'help'	2020-06-14 01:57:21 +09:00
Makefile	isdn: capi: dead code removal	2019-12-11 09:12:38 +01:00