Commit 7138ef74 authored Nov 21, 2022 by Jan Kara Committed by Greg Kroah-Hartman Jan 18, 2023

ext4: avoid BUG_ON when creating xattrs



commit b40ebaf63851b3a401b0dc9263843538f64f5ce6 upstream.

Commit fb0a387d ("ext4: limit block allocations for indirect-block
files to < 2^32") added code to try to allocate xattr block with 32-bit
block number for indirect block based files on the grounds that these
files cannot use larger block numbers. It also added BUG_ON when
allocated block could not fit into 32 bits. This is however bogus
reasoning because xattr block is stored in inode->i_file_acl and
inode->i_file_acl_hi and as such even indirect block based files can
happily use full 48 bits for xattr block number. The proper handling
seems to be there basically since 64-bit block number support was added.
So remove the bogus limitation and BUG_ON.

Cc: Eric Sandeen <sandeen@redhat.com>
Fixes: fb0a387d ("ext4: limit block allocations for indirect-block files to < 2^32")
Signed-off-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20221121130929.32031-1-jack@suse.cz


Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: stable@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

parent 4d84ec8e

fs/ext4/xattr.c

+0 −8

Original line number	Diff line number	Diff line
		@@ -2066,19 +2066,11 @@ ext4_xattr_block_set(handle_t handle, struct inode inode,

		goal = ext4_group_first_block_no(sb,
		EXT4_I(inode)->i_block_group);

		/* non-extent files can't have physical blocks past 2^32 */
		if (!(ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS)))
		goal = goal & EXT4_MAX_BLOCK_FILE_PHYS;

		block = ext4_new_meta_blocks(handle, inode, goal, 0,
		NULL, &error);
		if (error)
		goto cleanup;

		if (!(ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS)))
		BUG_ON(block > EXT4_MAX_BLOCK_FILE_PHYS);

		ea_idebug(inode, "creating block %llu",
		(unsigned long long)block);