Re: [PATCH] pinctrl: stmfx: Fix hazardous u8[] to unsigned long cast
From: Linus Walleij <hidden>
Date: 2021-08-10 12:48:41
Also in:
lkml, stable
On Sun, Jul 25, 2021 at 8:08 PM Marc Zyngier [off-list ref] wrote:
Casting a small array of u8 to an unsigned long is *never* OK:
- it does funny thing when the array size is less than that of a long,
as it accesses random places in the stack
- it makes everything even more fun with a BE kernel
Fix this by building the unsigned long used as a bitmap byte by byte,
in a way that works across endianess and has no undefined behaviours.
An extra BUILD_BUG_ON() catches the unlikely case where the array
would be larger than a single unsigned long.
Fixes: 1490d9f841b1 ("pinctrl: Add STMFX GPIO expander Pinctrl/GPIO driver")
Signed-off-by: Marc Zyngier <maz@kernel.org>
Cc: stable@vger.kernel.org
Cc: Amelie Delaunay <amelie.delaunay@foss.st.com>
Cc: Linus Walleij <redacted>
Cc: Maxime Coquelin <mcoquelin.stm32@gmail.com>
Cc: Alexandre Torgue <alexandre.torgue@foss.st.com>Patch applied! Yours, Linus Walleij _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel