Eric W. Biederman 6db0e28b89 signal: Allow cifs and drbd to receive their terminating signals ... [ Upstream commit 33da8e7c81 ] My recent to change to only use force_sig for a synchronous events wound up breaking signal reception cifs and drbd. I had overlooked the fact that by default kthreads start out with all signals set to SIG_IGN. So a change I thought was safe turned out to have made it impossible for those kernel thread to catch their signals. Reverting the work on force_sig is a bad idea because what the code was doing was very much a misuse of force_sig. As the way force_sig ultimately allowed the signal to happen was to change the signal handler to SIG_DFL. Which after the first signal will allow userspace to send signals to these kernel threads. At least for wake_ack_receiver in drbd that does not appear actively wrong. So correct this problem by adding allow_kernel_signal that will allow signals whose siginfo reports they were sent by the kernel through, but will not allow userspace generated signals, and update cifs and drbd to call allow_kernel_signal in an appropriate place so that their thread can receive this signal. Fixing things this way ensures that userspace won't be able to send signals and cause problems, that it is clear which signals the threads are expecting to receive, and it guarantees that nothing else in the system will be affected. This change was partly inspired by similar cifs and drbd patches that added allow_signal. Reported-by: ronnie sahlberg <ronniesahlberg@gmail.com> Reported-by: Christoph Böhmwalder <christoph.boehmwalder@linbit.com> Tested-by: Christoph Böhmwalder <christoph.boehmwalder@linbit.com> Cc: Steve French <smfrench@gmail.com> Cc: Philipp Reisner <philipp.reisner@linbit.com> Cc: David Laight <David.Laight@ACULAB.COM> Fixes: 247bc9470b ("cifs: fix rmmod regression in cifs.ko caused by force_sig changes") Fixes: 72abe3bcf0 ("signal/cifs: Fix cifs_put_tcp_session to call send_sig instead of force_sig") Fixes: fee109901f ("signal/drbd: Use send_sig not force_sig") Fixes: 3cf5d076fb ("signal: Remove task parameter from force_sig") Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Sasha Levin <sashal@kernel.org>		2020-01-27 14:51:05 +01:00
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aoe
drbd	signal: Allow cifs and drbd to receive their terminating signals	2020-01-27 14:51:05 +01:00
mtip32xx
paride
rsxx	rsxx: add missed destroy_workqueue calls in remove	2019-12-13 08:51:06 +01:00
xen-blkback	xen/blkback: Avoid unmapping unmapped grant pages	2020-01-09 10:19:09 +01:00
zram	zram: fix race between backing_dev_show and backing_dev_store	2019-11-06 13:05:10 +01:00
amiflop.c	amiflop: clean up on errors during setup	2019-12-01 09:16:25 +01:00
ataflop.c
brd.c
cryptoloop.c
DAC960.c
DAC960.h
floppy.c	floppy: fix usercopy direction	2019-09-21 07:17:14 +02:00
Kconfig
loop.c	loop: fix no-unmap write-zeroes request behavior	2019-12-31 16:35:32 +01:00
loop.h
Makefile
nbd.c	nbd: fix shutdown and recv work deadlock v2	2019-12-31 16:36:36 +01:00
null_blk_main.c
null_blk_zoned.c
null_blk.h
pktcdvd.c	pktcdvd: remove warning on attempting to register non-passthrough dev	2019-10-07 18:57:15 +02:00
ps3disk.c
ps3vram.c
rbd_types.h
rbd.c	rbd: clear ->xferred on error from rbd_obj_issue_copyup()	2020-01-27 14:50:30 +01:00
skd_main.c	skd: fixup usage of legacy IO API	2019-12-01 09:16:20 +01:00
skd_s1120.h
sunvdc.c
swim_asm.S
swim.c
swim3.c
sx8.c
umem.c
umem.h
virtio_blk.c
xen-blkfront.c	xen/blkfront: Adjust indentation in xlvbd_alloc_gendisk	2020-01-23 08:21:36 +01:00
xsysace.c
z2ram.c