a0ee2ac039
Although unbinding a pinctrl driver requires root privileges but it still might be used theoretically in certain attacks (by triggering NULL pointer exception or memory corruption). Samsung pincontrol drivers are essential for system operation so their removal is not expected. They do not implement remove() driver callback and they are not buildable as modules. Suppression of the unbinding will prevent triggering NULL pointer exception like this (Odroid XU3): $ echo 13400000.pinctrl > /sys/bus/platform/drivers/samsung-pinctrl/unbind $ cat /sys/kernel/debug/gpio Unable to handle kernel NULL pointer dereference at virtual address 00000c44 pgd = ec41c000 [00000c44] *pgd=6d448835, *pte=00000000, *ppte=00000000 Internal error: Oops: 17 [#1] PREEMPT SMP ARM (samsung_gpio_get) from [<c034f9a0>] (gpiolib_seq_show+0x1b0/0x26c) (gpiolib_seq_show) from [<c01fb8c0>] (seq_read+0x304/0x4b8) (seq_read) from [<c02dbc78>] (full_proxy_read+0x4c/0x64) (full_proxy_read) from [<c01d9fb0>] (__vfs_read+0x2c/0x110) (__vfs_read) from [<c01db400>] (vfs_read+0x8c/0x110) (vfs_read) from [<c01db4c4>] (SyS_read+0x40/0x8c) (SyS_read) from [<c01078c0>] (ret_fast_syscall+0x0/0x3c) Suggested-by: Marek Szyprowski <m.szyprowski@samsung.com> Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com> Reviewed-by: Javier Martinez Canillas <javier@osg.samsung.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org> |
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| .. | ||
| Kconfig | ||
| Makefile | ||
| pinctrl-exynos5440.c | ||
| pinctrl-exynos.c | ||
| pinctrl-exynos.h | ||
| pinctrl-s3c24xx.c | ||
| pinctrl-s3c64xx.c | ||
| pinctrl-samsung.c | ||
| pinctrl-samsung.h | ||