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Commit 5aa1437d authored by Al Viro's avatar Al Viro
Browse files

ext2: fix a block leak 



open file, unlink it, then use ioctl(2) to make it immutable or
append only.  Now close it and watch the blocks *not* freed...

Immutable/append-only checks belong in ->setattr().
Note: the bug is old and backport to anything prior to 737f2e93
("ext2: convert to use the new truncate convention") will need
these checks lifted into ext2_setattr().

Cc: stable@kernel.org
Signed-off-by: default avatarAl Viro <viro@zeniv.linux.org.uk>
parent 3819bb0d

fs/ext2/inode.c

+0 −10
Original line number Diff line number Diff line
@@ -1264,21 +1264,11 @@ static void __ext2_truncate_blocks(struct inode *inode, loff_t offset) 


static void ext2_truncate_blocks(struct inode *inode, loff_t offset)

{

	/*

	 * XXX: it seems like a bug here that we don't allow

	 * IS_APPEND inode to have blocks-past-i_size trimmed off.

	 * review and fix this.

	 *

	 * Also would be nice to be able to handle IO errors and such,

	 * but that's probably too much to ask.

	 */

	if (!(S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode) ||

	    S_ISLNK(inode->i_mode)))

		return;

	if (ext2_inode_is_fast_symlink(inode))

		return;

	if (IS_APPEND(inode) || IS_IMMUTABLE(inode))

		return;



	dax_sem_down_write(EXT2_I(inode));

	__ext2_truncate_blocks(inode, offset);