Zhenzhong Duan fb56687038 ttyprintk: fix a potential deadlock in interrupt context issue ... commit 9a655c77ff upstream. tpk_write()/tpk_close() could be interrupted when holding a mutex, then in timer handler tpk_write() may be called again trying to acquire same mutex, lead to deadlock. Google syzbot reported this issue with CONFIG_DEBUG_ATOMIC_SLEEP enabled: BUG: sleeping function called from invalid context at kernel/locking/mutex.c:938 in_atomic(): 1, irqs_disabled(): 0, non_block: 0, pid: 0, name: swapper/1 1 lock held by swapper/1/0: ... Call Trace: <IRQ> dump_stack+0x197/0x210 ___might_sleep.cold+0x1fb/0x23e __might_sleep+0x95/0x190 __mutex_lock+0xc5/0x13c0 mutex_lock_nested+0x16/0x20 tpk_write+0x5d/0x340 resync_tnc+0x1b6/0x320 call_timer_fn+0x1ac/0x780 run_timer_softirq+0x6c3/0x1790 __do_softirq+0x262/0x98c irq_exit+0x19b/0x1e0 smp_apic_timer_interrupt+0x1a3/0x610 apic_timer_interrupt+0xf/0x20 </IRQ> See link https://syzkaller.appspot.com/bug?extid=2eeef62ee31f9460ad65 for more details. Fix it by using spinlock in process context instead of mutex and having interrupt disabled in critical section. Reported-by: syzbot+2eeef62ee31f9460ad65@syzkaller.appspotmail.com Signed-off-by: Zhenzhong Duan <zhenzhong.duan@gmail.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Link: https://lore.kernel.org/r/20200113034842.435-1-zhenzhong.duan@gmail.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>		2020-02-05 14:43:39 +00:00
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agp
hw_random	hwrng: omap3-rom - Fix missing clock by probing with device tree	2020-01-27 14:51:20 +01:00
ipmi	ipmi: kcs_bmc: handle devm_kasprintf() failure case	2020-01-27 14:50:21 +01:00
mwave
pcmcia
tpm	tpm: add check after commands attribs tab allocation	2019-12-17 20:34:42 +01:00
xilinx_hwicap
xillybus
adi.c
apm-emulation.c
applicom.c
applicom.h
bsr.c
ds1620.c
dsp56k.c
dtlk.c
efirtc.c
generic_nvram.c
hangcheck-timer.c
hpet.c
Kconfig
lp.c	lp: fix sparc64 LPSETTIMEOUT ioctl	2019-12-13 08:50:58 +01:00
Makefile
mbcs.c
mbcs.h
mem.c
misc.c
mspec.c
nsc_gpio.c
nvram.c
nwbutton.c
nwbutton.h
nwflash.c
pc8736x_gpio.c
powernv-op-panel.c
ppdev.c	ppdev: fix PPGETTIME/PPSETTIME ioctls	2019-12-17 20:35:13 +01:00
ps3flash.c
random.c	random: try to actively add entropy rather than passively wait for it	2020-02-01 09:37:11 +00:00
raw.c
rtc.c
scx200_gpio.c
snsc_event.c
snsc.c
snsc.h
sonypi.c
tb0219.c
tlclk.c
toshiba.c
ttyprintk.c	ttyprintk: fix a potential deadlock in interrupt context issue	2020-02-05 14:43:39 +00:00
uv_mmtimer.c
virtio_console.c