This is a note to let you know that I've just added the patch titled
pinctrl: single: Fix potential division by zero
to the 6.0-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
pinctrl-single-fix-potential-division-by-zero.patch
and it can be found in the queue-6.0 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit e88a843fbe8f4c931ad7056d55a8f30d628af911
Author: Maxim Korotkov <korotkov.maxim.s@xxxxxxxxx>
Date: Thu Nov 17 15:30:34 2022 +0300
pinctrl: single: Fix potential division by zero
[ Upstream commit 64c150339e7f6c5cbbe8c17a56ef2b3902612798 ]
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: 4e7e8017a80e ("pinctrl: pinctrl-single: enhance to configure multiple pins of different modules")
Signed-off-by: Maxim Korotkov <korotkov.maxim.s@xxxxxxxxx>
Reviewed-by: Tony Lindgren <tony@xxxxxxxxxxx>
Link: https://lore.kernel.org/r/20221117123034.27383-1-korotkov.maxim.s@xxxxxxxxx
Signed-off-by: Linus Walleij <linus.walleij@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/drivers/pinctrl/pinctrl-single.c b/drivers/pinctrl/pinctrl-single.c
index 67bec7ea0f8b..414ee6bb8ac9 100644
--- a/drivers/pinctrl/pinctrl-single.c
+++ b/drivers/pinctrl/pinctrl-single.c
@@ -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 {
