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Message-ID: <tencent_4D921A8D1F69E70C85C28875DC829E28EC09@qq.com>
From:   Linke Li <lilinke99@foxmail.com>
To:     linux-fsdevel@vger.kernel.org
Cc:     linux-kernel@vger.kernel.org, Jan Kara <jack@suse.cz>,
        Linke Li <lilinke99@gmail.com>
Subject: [PATCH] isofs: fix undefined behavior in iso_date()
Date:   Sun,  9 Jul 2023 14:42:55 +0800
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From: Linke Li <lilinke99@gmail.com>

Fix undefined behavior in the code by properly handling the left shift operaion.
Instead of left-shifting a negative value, explicitly cast -1 to an unsigned int
before the shift. This ensures well defined behavior and resolves any potential
issues.

Signed-off-by: Linke Li <lilinke99@gmail.com>
---
 fs/isofs/util.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/fs/isofs/util.c b/fs/isofs/util.c
index e88dba721661..4c902901401a 100644
--- a/fs/isofs/util.c
+++ b/fs/isofs/util.c
@@ -37,7 +37,7 @@ int iso_date(u8 *p, int flag)
 
 		/* sign extend */
 		if (tz & 0x80)
-			tz |= (-1 << 8);
+			tz |= ((unsigned int)-1 << 8);
 		
 		/* 
 		 * The timezone offset is unreliable on some disks,
-- 
2.25.1