Commit 77ea2a4b authored Jun 26, 2014 by Jan Kara Committed by Theodore Ts'o Jun 26, 2014

ext4: Fix block zeroing when punching holes in indirect block files



free_holes_block() passed local variable as a block pointer
to ext4_clear_blocks(). Thus ext4_clear_blocks() zeroed out this local
variable instead of proper place in inode / indirect block. We later
zero out proper place in inode / indirect block but don't dirty the
inode / buffer again which can lead to subtle issues (some changes e.g.
to inode can be lost).

Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>

parent e43bb4e6

fs/ext4/indirect.c

+2 −2

Original line number	Diff line number	Diff line
		@@ -1335,8 +1335,8 @@ static int free_hole_blocks(handle_t handle, struct inode inode,
		if (level == 0 \|\|
		(bh && all_zeroes((__le32 *)bh->b_data,
		(__le32 *)bh->b_data + addr_per_block))) {
		ext4_free_data(handle, inode, parent_bh, &blk, &blk+1);
		*i_data = 0;
		ext4_free_data(handle, inode, parent_bh,
		i_data, i_data + 1);
		}
		brelse(bh);
		bh = NULL;

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