Commit df4e7ac0 authored Dec 03, 2013 by Jan Kara

ext2: Fix oops in ext2_get_block() called from ext2_quota_write()



ext2_quota_write() doesn't properly setup bh it passes to
ext2_get_block() and thus we hit assertion BUG_ON(maxblocks == 0) in
ext2_get_blocks() (or we could actually ask for mapping arbitrary number
of blocks depending on whatever value was on stack).

Fix ext2_quota_write() to properly fill in number of blocks to map.

CC: stable@vger.kernel.org # >= 2.6.12
Reviewed-by: "Theodore Ts'o" <tytso@mit.edu>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reported-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Jan Kara <jack@suse.cz>

parent dea4f48a

fs/ext2/super.c

+1 −0

Original line number	Diff line number	Diff line
		@@ -1493,6 +1493,7 @@ static ssize_t ext2_quota_write(struct super_block *sb, int type,
		sb->s_blocksize - offset : towrite;

		tmp_bh.b_state = 0;
		tmp_bh.b_size = sb->s_blocksize;
		err = ext2_get_block(inode, blk, &tmp_bh, 1);
		if (err < 0)
		goto out;