Commit 64c15033 authored by Maxim Korotkov's avatar Maxim Korotkov Committed by Linus Walleij
Browse files

pinctrl: single: Fix potential division by zero 



There is a possibility of dividing by zero due to the pcs->bits_per_pin
if pcs->fmask() also has a value of zero and called fls
from asm-generic/bitops/builtin-fls.h or arch/x86/include/asm/bitops.h.
The function pcs_probe() has the branch that assigned to fmask 0 before
pcs_allocate_pin_table() was called

Found by Linux Verification Center (linuxtesting.org) with SVACE.

Fixes: 4e7e8017 ("pinctrl: pinctrl-single: enhance to configure multiple pins of different modules")
Signed-off-by: default avatarMaxim Korotkov <korotkov.maxim.s@gmail.com>
Reviewed-by: default avatarTony Lindgren <tony@atomide.com>
Link: https://lore.kernel.org/r/20221117123034.27383-1-korotkov.maxim.s@gmail.com


Signed-off-by: default avatarLinus Walleij <linus.walleij@linaro.org>
parent eb708140

drivers/pinctrl/pinctrl-single.c

+1 −1
Original line number Diff line number Diff line
@@ -727,7 +727,7 @@ static int pcs_allocate_pin_table(struct pcs_device *pcs) 


	mux_bytes = pcs->width / BITS_PER_BYTE;



	if (pcs->bits_per_mux) {

	if (pcs->bits_per_mux && pcs->fmask) {

		pcs->bits_per_pin = fls(pcs->fmask);

		nr_pins = (pcs->size * BITS_PER_BYTE) / pcs->bits_per_pin;

	} else {