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From: Baokun Li <libaokun1@huawei.com>
To: <linux-ext4@vger.kernel.org>
CC: <tytso@mit.edu>, <adilger.kernel@dilger.ca>, <jack@suse.cz>,
	<ritesh.list@gmail.com>, <ojaswin@linux.ibm.com>, <adobriyan@gmail.com>,
	<linux-kernel@vger.kernel.org>, <yi.zhang@huawei.com>,
	<yangerkun@huawei.com>, <libaokun1@huawei.com>
Subject: [PATCH v3 8/9] ext4: set the type of max_zeroout to unsigned int to avoid overflow
Date: Thu, 14 Mar 2024 22:09:05 +0800
Message-ID: <20240314140906.3064072-9-libaokun1@huawei.com>
In-Reply-To: <20240314140906.3064072-1-libaokun1@huawei.com>
References: <20240314140906.3064072-1-libaokun1@huawei.com>
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The max_zeroout is of type int and the s_extent_max_zeroout_kb is of
type uint, and the s_extent_max_zeroout_kb can be freely modified via
the sysfs interface. When the block size is 1024, max_zeroout may
overflow, so declare it as unsigned int to avoid overflow.

Signed-off-by: Baokun Li <libaokun1@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
---
 fs/ext4/extents.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/fs/ext4/extents.c b/fs/ext4/extents.c
index e57054bdc5fd..e067f2dd0335 100644
--- a/fs/ext4/extents.c
+++ b/fs/ext4/extents.c
@@ -3402,9 +3402,10 @@ static int ext4_ext_convert_to_initialized(handle_t *handle,
 	struct ext4_extent *ex, *abut_ex;
 	ext4_lblk_t ee_block, eof_block;
 	unsigned int ee_len, depth, map_len = map->m_len;
-	int allocated = 0, max_zeroout = 0;
 	int err = 0;
 	int split_flag = EXT4_EXT_DATA_VALID2;
+	int allocated = 0;
+	unsigned int max_zeroout = 0;
 
 	ext_debug(inode, "logical block %llu, max_blocks %u\n",
 		  (unsigned long long)map->m_lblk, map_len);
-- 
2.31.1