Re: [PATCH v3 1/1] gpiolib: acpi: Fix potential out-of-boundary left shift

From: Bartosz Golaszewski

Date: Wed Jan 28 2026 - 09:28:43 EST



On Wed, 28 Jan 2026 10:58:54 +0100, Andy Shevchenko wrote:
> GPIO Address Space handler gets a pointer to the in or out value.
> This value is supposed to be at least 64-bit, but it's not limited
> to be exactly 64-bit. When ACPI tables are being parsed, for
> the bigger Connection():s ACPICA creates a Buffer instead of regular
> Integer object. The Buffer exists as long as Namespace holds
> the certain Connection(). Hence we can access the necessary bits
> without worrying. On the other hand, the left shift, used in
> the code, is limited by 31 (on 32-bit platforms) and otherwise
> considered to be Undefined Behaviour. Also the code uses only
> the first 64-bit word for the value, and anything bigger than 63
> will be also subject to UB. Fix all this by modifying the code
> to correctly set or clear the respective bit in the bitmap constructed
> of 64-bit words.
>
> [...]

Applied, thanks!

[1/1] gpiolib: acpi: Fix potential out-of-boundary left shift
https://git.kernel.org/brgl/c/e64d1cb21a1c6ecd51bc1c94c83f6fc656f7c94d

Best regards,
--
Bartosz Golaszewski <bartosz.golaszewski@xxxxxxxxxxxxxxxx>