linux/drivers
Stephen Boyd baef1c90aa soc: qcom: rpmh: Avoid accessing freed memory from batch API
Using the batch API from the interconnect driver sometimes leads to a
KASAN error due to an access to freed memory. This is easier to trigger
with threadirqs on the kernel commandline.

 BUG: KASAN: use-after-free in rpmh_tx_done+0x114/0x12c
 Read of size 1 at addr fffffff51414ad84 by task irq/110-apps_rs/57

 CPU: 0 PID: 57 Comm: irq/110-apps_rs Tainted: G        W         4.19.10 #72
 Call trace:
  dump_backtrace+0x0/0x2f8
  show_stack+0x20/0x2c
  __dump_stack+0x20/0x28
  dump_stack+0xcc/0x10c
  print_address_description+0x74/0x240
  kasan_report+0x250/0x26c
  __asan_report_load1_noabort+0x20/0x2c
  rpmh_tx_done+0x114/0x12c
  tcs_tx_done+0x450/0x768
  irq_forced_thread_fn+0x58/0x9c
  irq_thread+0x120/0x1dc
  kthread+0x248/0x260
  ret_from_fork+0x10/0x18

 Allocated by task 385:
  kasan_kmalloc+0xac/0x148
  __kmalloc+0x170/0x1e4
  rpmh_write_batch+0x174/0x540
  qcom_icc_set+0x8dc/0x9ac
  icc_set+0x288/0x2e8
  a6xx_gmu_stop+0x320/0x3c0
  a6xx_pm_suspend+0x108/0x124
  adreno_suspend+0x50/0x60
  pm_generic_runtime_suspend+0x60/0x78
  __rpm_callback+0x214/0x32c
  rpm_callback+0x54/0x184
  rpm_suspend+0x3f8/0xa90
  pm_runtime_work+0xb4/0x178
  process_one_work+0x544/0xbc0
  worker_thread+0x514/0x7d0
  kthread+0x248/0x260
  ret_from_fork+0x10/0x18

 Freed by task 385:
  __kasan_slab_free+0x12c/0x1e0
  kasan_slab_free+0x10/0x1c
  kfree+0x134/0x588
  rpmh_write_batch+0x49c/0x540
  qcom_icc_set+0x8dc/0x9ac
  icc_set+0x288/0x2e8
  a6xx_gmu_stop+0x320/0x3c0
  a6xx_pm_suspend+0x108/0x124
  adreno_suspend+0x50/0x60
 cr50_spi spi5.0: SPI transfer timed out
  pm_generic_runtime_suspend+0x60/0x78
  __rpm_callback+0x214/0x32c
  rpm_callback+0x54/0x184
  rpm_suspend+0x3f8/0xa90
  pm_runtime_work+0xb4/0x178
  process_one_work+0x544/0xbc0
  worker_thread+0x514/0x7d0
  kthread+0x248/0x260
  ret_from_fork+0x10/0x18

 The buggy address belongs to the object at fffffff51414ac80
  which belongs to the cache kmalloc-512 of size 512
 The buggy address is located 260 bytes inside of
  512-byte region [fffffff51414ac80, fffffff51414ae80)
 The buggy address belongs to the page:
 page:ffffffbfd4505200 count:1 mapcount:0 mapping:fffffff51e00c680 index:0x0 compound_mapcount: 0
 flags: 0x4000000000008100(slab|head)
 raw: 4000000000008100 ffffffbfd4529008 ffffffbfd44f9208 fffffff51e00c680
 raw: 0000000000000000 0000000000200020 00000001ffffffff 0000000000000000
 page dumped because: kasan: bad access detected

 Memory state around the buggy address:
  fffffff51414ac80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
  fffffff51414ad00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 >fffffff51414ad80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                    ^
  fffffff51414ae00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
  fffffff51414ae80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc

The batch API sets the same completion for each rpmh message that's sent
and then loops through all the messages and waits for that single
completion declared on the stack to be completed before returning from
the function and freeing the message structures. Unfortunately, some
messages may still be in process and 'stuck' in the TCS. At some later
point, the tcs_tx_done() interrupt will run and try to process messages
that have already been freed at the end of rpmh_write_batch(). This will
in turn access the 'needs_free' member of the rpmh_request structure and
cause KASAN to complain. Furthermore, if there's a message that's
completed in rpmh_tx_done() and freed immediately after the complete()
call is made we'll be racing with potentially freed memory when
accessing the 'needs_free' member:

	CPU0                         CPU1
	----                         ----
	rpmh_tx_done()
	 complete(&compl)
	                             wait_for_completion(&compl)
	                             kfree(rpm_msg)
	 if (rpm_msg->needs_free)
	 <KASAN warning splat>

Let's fix this by allocating a chunk of completions for each message and
waiting for all of them to be completed before returning from the batch
API. Alternatively, we could wait for the last message in the batch, but
that may be a more complicated change because it looks like
tcs_tx_done() just iterates through the indices of the queue and
completes each message instead of tracking the last inserted message and
completing that first.

Fixes: c8790cb6da ("drivers: qcom: rpmh: add support for batch RPMH request")
Cc: Lina Iyer <ilina@codeaurora.org>
Cc: "Raju P.L.S.S.S.N" <rplsssn@codeaurora.org>
Cc: Matthias Kaehlcke <mka@chromium.org>
Cc: Evan Green <evgreen@chromium.org>
Cc: stable@vger.kernel.org
Reviewed-by: Lina Iyer <ilina@codeaurora.org>
Reviewed-by: Evan Green <evgreen@chromium.org>
Signed-off-by: Stephen Boyd <swboyd@chromium.org>
Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Signed-off-by: Andy Gross <andy.gross@linaro.org>
2019-02-01 16:08:45 -06:00
..
accessibility
acpi Remove 'type' argument from access_ok() function 2019-01-03 18:57:57 -08:00
amba
android binder: implement binderfs 2018-12-19 09:40:13 +01:00
ata for-4.21/libata-20190102 2019-01-02 18:47:56 -08:00
atm
auxdisplay auxdisplay: charlcd: fix x/y command parsing 2018-12-21 21:27:21 +01:00
base Merge branch 'mount.part1' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2019-01-05 13:25:58 -08:00
bcma
block block: sunvdc: don't run hw queue synchronously from irq context 2019-01-03 08:21:47 -07:00
bluetooth Bluetooth: hci_bcm: Handle specific unknown packets after firmware loading 2018-12-19 13:43:42 +01:00
bus ARM: SoC driver updates 2018-12-31 17:32:35 -08:00
cdrom gdrom: fix a memory leak bug 2018-12-29 08:20:44 -07:00
char Remove 'type' argument from access_ok() function 2019-01-03 18:57:57 -08:00
clk Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input 2019-01-02 18:56:59 -08:00
clocksource arch/csky patches for 4.21-rc1 2019-01-05 09:50:07 -08:00
connector
cpufreq powerpc updates for 4.21 2018-12-27 10:43:24 -08:00
cpuidle powerpc updates for 4.21 2018-12-27 10:43:24 -08:00
crypto Remove 'type' argument from access_ok() function 2019-01-03 18:57:57 -08:00
dax mm, devm_memremap_pages: fix shutdown handling 2018-12-28 12:11:47 -08:00
dca
devfreq
dio
dma Merge branch 'next/drivers' into next/late 2019-01-04 14:31:38 -08:00
dma-buf drivers/dma-buf/udmabuf.c: convert to use vm_fault_t 2019-01-04 13:13:46 -08:00
edac EDAC, fsl_ddr: Add LS1021A to the list of supported hardware 2018-12-19 11:57:45 +01:00
eisa
extcon
firewire FireWire (IEEE 1394) subsystem patch: 2019-01-05 18:33:21 -08:00
firmware arm64 fixes for -rc1 2019-01-05 11:28:39 -08:00
fmc
fpga Remove 'type' argument from access_ok() function 2019-01-03 18:57:57 -08:00
fsi
gnss
gpio This is the bulk of GPIO changes for the v4.21 kernel series: 2018-12-28 20:00:21 -08:00
gpu drm i915 gvt, amdgpu, core fixes 2019-01-05 18:25:19 -08:00
hid Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/hid/hid 2019-01-05 17:53:40 -08:00
hsi
hv Char/Misc driver patches for 4.21-rc1 2018-12-28 20:54:57 -08:00
hwmon Kconfig updates for v4.21 2018-12-29 13:03:29 -08:00
hwspinlock hwspinlock: fix return value check in stm32_hwspinlock_probe() 2019-01-03 11:42:10 -08:00
hwtracing intel_th: msu: Fix an off-by-one in attribute store 2018-12-19 20:21:06 +01:00
i2c Merge branch 'i2c/for-5.0' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux 2019-01-05 18:13:35 -08:00
i3c
ide for-4.21/block-20181221 2018-12-28 13:19:59 -08:00
idle
iio Staging/IIO driver patches for 4.21-rc1 2018-12-28 20:39:58 -08:00
infiniband 4.21 merge window 2nd pull request 2019-01-05 18:20:51 -08:00
input Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input 2019-01-02 18:56:59 -08:00
iommu IOMMU Updates for Linux v4.21 2019-01-01 15:55:29 -08:00
ipack
irqchip Xtensa updates for v4.21: 2018-12-29 09:40:40 -08:00
isdn isdn: fix kernel-infoleak in capi_unlocked_ioctl 2019-01-02 10:31:39 -08:00
leds LEDs for 4.21-rc1 2018-12-25 14:52:50 -08:00
lightnvm lightnvm: pblk: fix use-after-free bug 2018-12-22 14:45:35 -07:00
macintosh Remove 'type' argument from access_ok() function 2019-01-03 18:57:57 -08:00
mailbox mailbox: tegra-hsp: Use device-managed registration API 2018-12-21 22:31:26 -06:00
mcb
md Merge branch 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/shli/md into for-linus 2019-01-03 08:21:02 -07:00
media Remove 'type' argument from access_ok() function 2019-01-03 18:57:57 -08:00
memory ARM: SoC: late updates 2019-01-05 11:30:37 -08:00
memstick MMC core: 2018-12-28 16:52:18 -08:00
message scsi: flip the default on use_clustering 2018-12-18 23:13:12 -05:00
mfd
misc Merge branch 'i2c/for-5.0' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux 2019-01-05 18:13:35 -08:00
mmc MMC core: 2018-12-28 16:52:18 -08:00
mtd Kbuild updates for v4.21 2018-12-29 12:03:17 -08:00
mux
net Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2019-01-03 12:53:47 -08:00
nfc
ntb
nubus
nvdimm Merge branch 'akpm' (patches from Andrew) 2018-12-28 16:55:46 -08:00
nvme nvme-pci: trace SQ status on completions 2018-12-19 08:35:36 +01:00
nvmem
of Merge tag 'devicetree-for-4.21' of git://git.kernel.org/pub/scm/linux/kernel/git/robh/linux 2018-12-28 20:08:34 -08:00
opp OPP: Add support for parsing the 'opp-level' property 2019-01-22 15:06:11 -06:00
oprofile
parisc Kconfig file consolidation for v4.21 2018-12-29 13:40:29 -08:00
parport
pci pci-v4.21-changes 2019-01-05 17:57:34 -08:00
pcmcia Included in this update: 2019-01-05 11:23:17 -08:00
perf drivers/perf: hisi: Fixup one DDRC PMU register offset 2019-01-04 10:13:27 +00:00
phy
pinctrl Pin control bulk changes for the v4.21 kernel cycle: 2019-01-01 13:19:16 -08:00
platform chrome platform changes for v4.21 2019-01-06 11:40:06 -08:00
pnp Remove 'type' argument from access_ok() function 2019-01-03 18:57:57 -08:00
power power supply and reset changes for the v4.21 series 2018-12-28 20:22:45 -08:00
powercap
pps Kconfig updates for v4.21 2018-12-29 13:03:29 -08:00
ps3
ptp Char/Misc driver patches for 4.21-rc1 2018-12-28 20:54:57 -08:00
pwm pwm: imx: Add ipg clock operation 2018-12-24 12:06:56 +01:00
rapidio
ras treewide: surround Kconfig file paths with double quotes 2018-12-22 00:25:54 +09:00
regulator Merge remote-tracking branch 'regulator/topic/coupled' into regulator-next 2018-12-21 13:43:35 +00:00
remoteproc
reset
rpmsg
rtc RTC for 4.21 2019-01-01 13:24:31 -08:00
s390 s390 updates for the 4.21 merge window 2019-01-02 18:37:01 -08:00
sbus Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc-next 2018-12-26 10:32:18 -08:00
scsi Remove 'type' argument from access_ok() function 2019-01-03 18:57:57 -08:00
sfi
sh
siox
slimbus
sn
soc soc: qcom: rpmh: Avoid accessing freed memory from batch API 2019-02-01 16:08:45 -06:00
soundwire
spi spi: Updates for v4.21 2018-12-25 14:43:54 -08:00
spmi
ssb
staging Remove 'type' argument from access_ok() function 2019-01-03 18:57:57 -08:00
target SCSI misc on 20181224 2018-12-28 14:48:06 -08:00
tc
tee OP-TEE dynamic shm log message 2018-12-31 13:06:30 -08:00
thermal Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/rzhang/linux 2019-01-05 16:07:28 -08:00
thunderbolt
tty ARM: SoC: late updates 2019-01-05 11:30:37 -08:00
uio Char/Misc driver patches for 4.21-rc1 2018-12-28 20:54:57 -08:00
usb pci-v4.21-changes 2019-01-05 17:57:34 -08:00
uwb
vfio IOMMU Updates for Linux v4.21 2019-01-01 15:55:29 -08:00
vhost Remove 'type' argument from access_ok() function 2019-01-03 18:57:57 -08:00
video fbdev changes for v4.21: 2019-01-05 18:15:37 -08:00
virt
virtio virtio, vhost: features, fixes, cleanups 2019-01-02 18:54:45 -08:00
visorbus
vlynq
vme
w1 treewide: surround Kconfig file paths with double quotes 2018-12-22 00:25:54 +09:00
watchdog linux-watchdog 4.21-rc1 tag 2019-01-01 13:16:45 -08:00
xen Remove 'type' argument from access_ok() function 2019-01-03 18:57:57 -08:00
zorro
Kconfig Kconfig file consolidation for v4.21 2018-12-29 13:40:29 -08:00
Makefile