linux/drivers/char
Jan Dabros 23393c6461 char: tpm: Protect tpm_pm_suspend with locks
Currently tpm transactions are executed unconditionally in
tpm_pm_suspend() function, which may lead to races with other tpm
accessors in the system.

Specifically, the hw_random tpm driver makes use of tpm_get_random(),
and this function is called in a loop from a kthread, which means it's
not frozen alongside userspace, and so can race with the work done
during system suspend:

  tpm tpm0: tpm_transmit: tpm_recv: error -52
  tpm tpm0: invalid TPM_STS.x 0xff, dumping stack for forensics
  CPU: 0 PID: 1 Comm: init Not tainted 6.1.0-rc5+ #135
  Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.0-20220807_005459-localhost 04/01/2014
  Call Trace:
   tpm_tis_status.cold+0x19/0x20
   tpm_transmit+0x13b/0x390
   tpm_transmit_cmd+0x20/0x80
   tpm1_pm_suspend+0xa6/0x110
   tpm_pm_suspend+0x53/0x80
   __pnp_bus_suspend+0x35/0xe0
   __device_suspend+0x10f/0x350

Fix this by calling tpm_try_get_ops(), which itself is a wrapper around
tpm_chip_start(), but takes the appropriate mutex.

Signed-off-by: Jan Dabros <jsd@semihalf.com>
Reported-by: Vlastimil Babka <vbabka@suse.cz>
Tested-by: Jason A. Donenfeld <Jason@zx2c4.com>
Tested-by: Vlastimil Babka <vbabka@suse.cz>
Link: https://lore.kernel.org/all/c5ba47ef-393f-1fba-30bd-1230d1b4b592@suse.cz/
Cc: stable@vger.kernel.org
Fixes: e891db1a18 ("tpm: turn on TPM on suspend for TPM 1.x")
[Jason: reworked commit message, added metadata]
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2022-12-04 12:49:13 -08:00
..
agp IOMMU Updates for Linux v5.20/v6.0: 2022-08-06 10:42:38 -07:00
hw_random hwrng: bcm2835 - use hwrng_msleep() instead of cpu_relax() 2022-10-14 19:03:09 +08:00
ipmi Fix a bunch of little problems in IPMI 2022-10-11 10:42:25 -07:00
mwave char/mwave: Adjust io port register size 2021-12-03 14:27:06 +01:00
pcmcia tty: Make ->set_termios() old ktermios const 2022-08-30 14:22:35 +02:00
tpm char: tpm: Protect tpm_pm_suspend with locks 2022-12-04 12:49:13 -08:00
xilinx_hwicap xilinx_hwicap: cleanup comments 2022-02-25 12:08:57 +01:00
xillybus char: xillybus: fix a refcount leak in cleanup_dev() 2022-04-24 17:30:45 +02:00
adi.c
apm-emulation.c apm-emulation: drop unexpected word "the" in the comments 2022-06-27 16:15:27 +02:00
applicom.c applicom: unneed to initialise statics to 0 2021-12-21 10:14:08 +01:00
applicom.h
bsr.c powerpc/BSR: Make use of the helper macro LIST_HEAD() 2022-02-25 12:10:15 +01:00
ds1620.c
dsp56k.c
dtlk.c
hangcheck-timer.c
hpet.c hpet: remove unused writeq/readq function definitions 2022-02-04 16:45:39 +01:00
Kconfig Char / Misc driver changes for 6.0-rc1 2022-08-04 11:05:48 -07:00
lp.c char: lp: remove redundant initialization of err 2022-06-10 15:29:50 +02:00
Makefile char: remove VR41XX related char driver 2022-07-28 16:12:33 +02:00
mem.c random: restore O_NONBLOCK support 2022-09-23 12:27:57 +02:00
misc.c char: misc: remove usage of list iterator past the loop body 2022-04-24 17:15:12 +02:00
mspec.c
nsc_gpio.c
nvram.c
nwbutton.c
nwbutton.h
nwflash.c
pc8736x_gpio.c
powernv-op-panel.c
ppdev.c
ps3flash.c
random.c random: use arch_get_random*_early() in random_init() 2022-10-29 00:24:03 +02:00
scx200_gpio.c
sonypi.c
tlclk.c
toshiba.c
ttyprintk.c char: ttyprintk: register console 2022-04-22 16:24:47 +02:00
uv_mmtimer.c
virtio_console.c Char/Misc and other driver updates for 5.18-rc1 2022-03-28 12:27:35 -07:00