From: Linus Torvalds torvalds@linux-foundation.org
[ Upstream commit fc68f42aa737dc15e7665a4101d4168aadb8e4c4 ]
Commit 71f642833284 ("ACPI: utils: Fix reference counting in for_each_acpi_dev_match()") started doing "acpi_dev_put()" on a pointer that was possibly NULL. That fails miserably, because that helper inline function is not set up to handle that case.
Just make acpi_dev_put() silently accept a NULL pointer, rather than calling down to put_device() with an invalid offset off that NULL pointer.
Link: https://lore.kernel.org/lkml/a607c149-6bf6-0fd0-0e31-100378504da2@kernel.dk/ Reported-and-tested-by: Jens Axboe axboe@kernel.dk Tested-by: Daniel Scally djrscally@gmail.com Cc: Andy Shevchenko andy.shevchenko@gmail.com Signed-off-by: Linus Torvalds torvalds@linux-foundation.org Signed-off-by: Sasha Levin sashal@kernel.org --- include/acpi/acpi_bus.h | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/include/acpi/acpi_bus.h b/include/acpi/acpi_bus.h index 3a82faac5767..cd98af6ba155 100644 --- a/include/acpi/acpi_bus.h +++ b/include/acpi/acpi_bus.h @@ -716,7 +716,8 @@ static inline struct acpi_device *acpi_dev_get(struct acpi_device *adev)
static inline void acpi_dev_put(struct acpi_device *adev) { - put_device(&adev->dev); + if (adev) + put_device(&adev->dev); } #else /* CONFIG_ACPI */