Commit f7a4463d authored May 17, 2018 by Al Viro Committed by Greg Kroah-Hartman May 25, 2018

ext2: fix a block leak



commit 5aa1437d2d9a068c0334bd7c9dafa8ec4f97f13b upstream.

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: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

parent 85611642

fs/ext2/inode.c

+0 −10

Original line number	Diff line number	Diff line
		@@ -1169,21 +1169,11 @@ do_indirects:

		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;
		__ext2_truncate_blocks(inode, offset);
		}