From: Dan Carpenter <dan.carpenter@linaro.org>
Date: Wed, 25 Oct 2023 11:58:18 +0000 (+0300)
Subject: pwm: Fix double shift bug
X-Git-Tag: v4.14.331~28
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=bce1f7c7e9812da57de1dda293cba87c693e9958;p=thirdparty%2Fkernel%2Fstable.git

pwm: Fix double shift bug

[ 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>
---

diff --git a/include/linux/pwm.h b/include/linux/pwm.h
index bd7d611d63e91..c6e981035c3fd 100644
--- a/include/linux/pwm.h
+++ b/include/linux/pwm.h
@@ -44,8 +44,8 @@ struct pwm_args {
 };
 
 enum {
-	PWMF_REQUESTED = 1 << 0,
-	PWMF_EXPORTED = 1 << 1,
+	PWMF_REQUESTED = 0,
+	PWMF_EXPORTED = 1,
 };
 
 /*