linux-kernel - [PATCH 1/2] soundwire: bus: Prevent infinite loop in sdw_ch_mask_to

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite for Android: free password hash cracker in your pocket

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:   Thu, 2 Feb 2023 15:42:11 +0000
From:   Richard Fitzgerald <rf@...nsource.cirrus.com>
To:     <vkoul@...nel.org>, <yung-chuan.liao@...ux.intel.com>,
        <pierre-louis.bossart@...ux.intel.com>, <sanyog.r.kale@...el.com>
CC:     <alsa-devel@...a-project.org>, <linux-kernel@...r.kernel.org>,
        <patches@...nsource.cirrus.com>,
        Richard Fitzgerald <rf@...nsource.cirrus.com>
Subject: [PATCH 1/2] soundwire: bus: Prevent infinite loop in sdw_ch_mask_to_ch()

Define the ch_mask argument of sdw_ch_mask_to_ch() as an unsigned
so that the shift right is guaranteed to eventually make the
value of ch_mask==0.

Previously ch_mask was defined as a signed int, but a right
shift of a signed value preserves the sign bit. So if the sign
bit was 1, ch_mask would never become 0 and the for loop would
be infinite.

Signed-off-by: Richard Fitzgerald <rf@...nsource.cirrus.com>
---
 drivers/soundwire/bus.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/soundwire/bus.h b/drivers/soundwire/bus.h
index 7631ef5e71fb..28bedc919b78 100644
--- a/drivers/soundwire/bus.h
+++ b/drivers/soundwire/bus.h
@@ -160,7 +160,7 @@ int sdw_fill_msg(struct sdw_msg *msg, struct sdw_slave *slave,
 		 u32 addr, size_t count, u16 dev_num, u8 flags, u8 *buf);
 
 /* Retrieve and return channel count from channel mask */
-static inline int sdw_ch_mask_to_ch(int ch_mask)
+static inline int sdw_ch_mask_to_ch(unsigned int ch_mask)
 {
 	int c = 0;
 
-- 
2.30.2