Commit 29ec9bed authored by Zhang Yi's avatar Zhang Yi Committed by Theodore Ts'o
Browse files

ext4: fix incorrect punch max_end 



For the extents based inodes, the maxbytes should be sb->s_maxbytes
instead of sbi->s_bitmap_maxbytes. Additionally, for the calculation of
max_end, the -sb->s_blocksize operation is necessary only for
indirect-block based inodes. Correct the maxbytes and max_end value to
correct the behavior of punch hole.

Fixes: 2da37622 ("ext4: limit length to bitmap_maxbytes - blocksize in punch_hole")
Signed-off-by: default avatarZhang Yi <yi.zhang@huawei.com>
Reviewed-by: default avatarJan Kara <jack@suse.cz>
Reviewed-by: default avatarBaokun Li <libaokun1@huawei.com>
Link: https://patch.msgid.link/20250506012009.3896990-2-yi.zhang@huaweicloud.com


Signed-off-by: default avatarTheodore Ts'o <tytso@mit.edu>
Cc: stable@kernel.org
parent b5e58bcd

fs/ext4/inode.c

+9 −3
Original line number Diff line number Diff line
@@ -4051,7 +4051,7 @@ int ext4_punch_hole(struct file *file, loff_t offset, loff_t length) 
	struct inode *inode = file_inode(file);

	struct super_block *sb = inode->i_sb;

	ext4_lblk_t start_lblk, end_lblk;

	loff_t max_end = EXT4_SB(sb)->s_bitmap_maxbytes - sb->s_blocksize;

	loff_t max_end = sb->s_maxbytes;

	loff_t end = offset + length;

	handle_t *handle;

	unsigned int credits;
@@ -4060,14 +4060,20 @@ int ext4_punch_hole(struct file *file, loff_t offset, loff_t length) 
	trace_ext4_punch_hole(inode, offset, length, 0);

	WARN_ON_ONCE(!inode_is_locked(inode));



	/*

	 * For indirect-block based inodes, make sure that the hole within

	 * one block before last range.

	 */

	if (!ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS))

		max_end = EXT4_SB(sb)->s_bitmap_maxbytes - sb->s_blocksize;



	/* No need to punch hole beyond i_size */

	if (offset >= inode->i_size || offset >= max_end)

		return 0;



	/*

	 * If the hole extends beyond i_size, set the hole to end after

	 * the page that contains i_size, and also make sure that the hole

	 * within one block before last range.

	 * the page that contains i_size.

	 */

	if (end > inode->i_size)

		end = round_up(inode->i_size, PAGE_SIZE);