hfsplus: prevent btree data loss on root split
Creating, renaming or deleting a file may cause catalog corruption and
data loss. This bug is randomly triggered by xfstests generic/027, but
here is a faster reproducer:
truncate -s 50M fs.iso
mkfs.hfsplus fs.iso
mount fs.iso /mnt
i=100
while [ $i -le 150 ]; do
touch /mnt/$i &>/dev/null
((++i))
done
i=100
while [ $i -le 150 ]; do
mv /mnt/$i /mnt/$(perl -e "print $i x82") &>/dev/null
((++i))
done
umount /mnt
fsck.hfsplus -n fs.iso
The bug is triggered whenever hfs_brec_update_parent() needs to split the
root node. The height of the btree is not increased, which leaves the new
node orphaned and its records lost.
Link: http://lkml.kernel.org/r/26d882184fc43043a810114258f45277752186c7.1535682461.git.ernesto.mnd.fernandez@gmail.com
Signed-off-by: Ernesto A. Fernández <ernesto.mnd.fernandez@gmail.com>
Cc: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
1 file changed
