[PATCH 19/22] ASoC: codecs: wcd934x: Remove undefined behavior in wcd934x_slim_irq_handler()

From: Josh Poimboeuf
Date: Mon Mar 24 2025 - 18:00:55 EST


If port_id is negative, the shift counts in wcd934x_slim_irq_handler()
also become negative, resulting in undefined behavior due to shift out
of bounds.

If I'm reading the code correctly, that appears to be not possible, but
with KCOV enabled, Clang's range analysis isn't always able to determine
that and generates undefined behavior.

As a result the code generation isn't optimal, and undefined behavior
should be avoided regardless. Improve code generation and remove the
undefined behavior by converting the signed variables to unsigned.

Fixes the following warning with UBSAN:

sound/soc/codecs/snd-soc-wcd934x.o: warning: objtool: .text.wcd934x_slim_irq_handler: unexpected end of section

Cc: Srinivas Kandagatla <srinivas.kandagatla@xxxxxxxxxx>
Reported-by: kernel test robot <lkp@xxxxxxxxx>
Closes: https://lore.kernel.org/oe-kbuild-all/202503180044.oH9gyPeg-lkp@xxxxxxxxx/
Signed-off-by: Josh Poimboeuf <jpoimboe@xxxxxxxxxx>
---
sound/soc/codecs/wcd934x.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/sound/soc/codecs/wcd934x.c b/sound/soc/codecs/wcd934x.c
index 910852eb9698..c7f1b28f3b23 100644
--- a/sound/soc/codecs/wcd934x.c
+++ b/sound/soc/codecs/wcd934x.c
@@ -2273,7 +2273,7 @@ static irqreturn_t wcd934x_slim_irq_handler(int irq, void *data)
{
struct wcd934x_codec *wcd = data;
unsigned long status = 0;
- int i, j, port_id;
+ unsigned int i, j, port_id;
unsigned int val, int_val = 0;
irqreturn_t ret = IRQ_NONE;
bool tx;
--
2.48.1