2022-08-25 11:38:07

by Xiaolei Wang

[permalink] [raw]
Subject: [v2][PATCH] regulator: pfuze100: Fix the global-out-of-bounds access in pfuze100_regulator_probe()

The pfuze_chip::regulator_descs is an array of size
PFUZE100_MAX_REGULATOR, the pfuze_chip::pfuze_regulators
is the pointer to the real regulators of a specific device.
The number of real regulator is supposed to be less than
the PFUZE100_MAX_REGULATOR, so we should use the size of
'regulator_num * sizeof(struct pfuze_regulator)' in memcpy().
This fixes the out of bounds access bug reported by KASAN.
BUG: KASAN: global-out-of-bounds in pfuze100_regulator_probe+0x380/0x8b8
Read of size 3968 at addr c3390640 by task swapper/0/1

CPU: 0 PID: 1 Comm: swapper/0 Not tainted 6.0.0-rc1-yocto-standard+ #2
Hardware name: Freescale i.MX6 SoloX (Device Tree)
unwind_backtrace from show_stack+0x18/0x1c
show_stack from dump_stack_lvl+0x68/0x90
dump_stack_lvl from print_report+0x58/0x4c8
print_report from kasan_report+0x7c/0x98
kasan_report from kasan_check_range+0x20/0x170
kasan_check_range from memcpy+0x28/0x68
memcpy from pfuze100_regulator_probe+0x380/0x8b8
pfuze100_regulator_probe from i2c_device_probe+0x37c/0x39c
i2c_device_probe from really_probe+0x1cc/0x398
really_probe from __driver_probe_device+0x118/0x124
__driver_probe_device from driver_probe_device+0x5c/0xf0
driver_probe_device from __driver_attach+0x144/0x160
__driver_attach from bus_for_each_dev+0xf4/0x12c
bus_for_each_dev from bus_add_driver+0x124/0x264
bus_add_driver from driver_register+0x130/0x188
driver_register from i2c_register_driver+0x80/0xa8
i2c_register_driver from do_one_initcall+0x180/0x39c
do_one_initcall from kernel_init_freeable+0x374/0x3cc
kernel_init_freeable from kernel_init+0x1c/0x150
kernel_init from ret_from_fork+0x14/0x2c

Signed-off-by: Xiaolei Wang <[email protected]>
---
drivers/regulator/pfuze100-regulator.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/regulator/pfuze100-regulator.c b/drivers/regulator/pfuze100-regulator.c
index 6b617024a67d..d899d6e98fb8 100644
--- a/drivers/regulator/pfuze100-regulator.c
+++ b/drivers/regulator/pfuze100-regulator.c
@@ -766,7 +766,7 @@ static int pfuze100_regulator_probe(struct i2c_client *client,
((pfuze_chip->chip_id == PFUZE3000) ? "3000" : "3001"))));

memcpy(pfuze_chip->regulator_descs, pfuze_chip->pfuze_regulators,
- sizeof(pfuze_chip->regulator_descs));
+ regulator_num * sizeof(struct pfuze_regulator));

ret = pfuze_parse_regulators_dt(pfuze_chip);
if (ret)
--
2.25.1


2022-08-25 13:38:51

by Mark Brown

[permalink] [raw]
Subject: Re: [v2][PATCH] regulator: pfuze100: Fix the global-out-of-bounds access in pfuze100_regulator_probe()

On Thu, 25 Aug 2022 19:19:22 +0800, Xiaolei Wang wrote:
> The pfuze_chip::regulator_descs is an array of size
> PFUZE100_MAX_REGULATOR, the pfuze_chip::pfuze_regulators
> is the pointer to the real regulators of a specific device.
> The number of real regulator is supposed to be less than
> the PFUZE100_MAX_REGULATOR, so we should use the size of
> 'regulator_num * sizeof(struct pfuze_regulator)' in memcpy().
> This fixes the out of bounds access bug reported by KASAN.
> BUG: KASAN: global-out-of-bounds in pfuze100_regulator_probe+0x380/0x8b8
> Read of size 3968 at addr c3390640 by task swapper/0/1
>
> [...]

Applied to

https://git.kernel.org/pub/scm/linux/kernel/git/broonie/regulator.git for-next

Thanks!

[1/1] regulator: pfuze100: Fix the global-out-of-bounds access in pfuze100_regulator_probe()
commit: 78e1e867f44e6bdc72c0e6a2609a3407642fb30b

All being well this means that it will be integrated into the linux-next
tree (usually sometime in the next 24 hours) and sent to Linus during
the next merge window (or sooner if it is a bug fix), however if
problems are discovered then the patch may be dropped or reverted.

You may get further e-mails resulting from automated or manual testing
and review of the tree, please engage with people reporting problems and
send followup patches addressing any issues that are reported if needed.

If any updates are required or you are submitting further changes they
should be sent as incremental updates against current git, existing
patches will not be replaced.

Please add any relevant lists and maintainers to the CCs when replying
to this mail.

Thanks,
Mark