pwm: Fix double shift bug
authorDan Carpenter <dan.carpenter@linaro.org>
Wed, 25 Oct 2023 11:58:18 +0000 (14:58 +0300)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Tue, 28 Nov 2023 17:19:48 +0000 (17:19 +0000)
[ Upstream commit d27abbfd4888d79dd24baf50e774631046ac4732 ]

These enums are passed to set/test_bit().  The set/test_bit() functions
take a bit number instead of a shifted value.  Passing a shifted value
is a double shift bug like doing BIT(BIT(1)).  The double shift bug
doesn't cause a problem here because we are only checking 0 and 1 but
if the value was 5 or above then it can lead to a buffer overflow.

Signed-off-by: Dan Carpenter <dan.carpenter@linaro.org>
Reviewed-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Reviewed-by: Sam Protsenko <semen.protsenko@linaro.org>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
include/linux/pwm.h

index d2f9f69..fe0f38c 100644 (file)
@@ -41,8 +41,8 @@ struct pwm_args {
 };
 
 enum {
-       PWMF_REQUESTED = 1 << 0,
-       PWMF_EXPORTED = 1 << 1,
+       PWMF_REQUESTED = 0,
+       PWMF_EXPORTED = 1,
 };
 
 /*