From: Josh Poimboeuf jpoimboe@kernel.org
[ Upstream commit 060aed9c0093b341480770457093449771cf1496 ]
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
Reported-by: kernel test robot lkp@intel.com Signed-off-by: Josh Poimboeuf jpoimboe@kernel.org Signed-off-by: Ingo Molnar mingo@kernel.org Acked-by: Mark Brown broonie@kernel.org Cc: Srinivas Kandagatla srinivas.kandagatla@linaro.org Cc: Liam Girdwood lgirdwood@gmail.com Cc: Jaroslav Kysela perex@perex.cz Cc: Takashi Iwai tiwai@suse.com Cc: Linus Torvalds torvalds@linux-foundation.org Link: https://lore.kernel.org/r/7e863839ec7301bf9c0f429a03873d44e484c31c.174285284... Closes: https://lore.kernel.org/oe-kbuild-all/202503180044.oH9gyPeg-lkp@intel.com/ Signed-off-by: Sasha Levin sashal@kernel.org --- 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 0b5999c819db9..04c50f9acda18 100644 --- a/sound/soc/codecs/wcd934x.c +++ b/sound/soc/codecs/wcd934x.c @@ -2281,7 +2281,7 @@ 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;