github-mirror/linux
1
0
Fork 0
mirror of https://github.com/torvalds/linux.git synced 2026-06-07 22:14:04 +02:00
Code Issues Actions Packages Projects Releases Wiki Activity Graph

hfsplus: prevent btree data loss on root split

Browse Source 
[ Upstream commit 0a3021d4f5 ]

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>
Signed-off-by: Sasha Levin <sashal@kernel.org>
This commit is contained in:
Ernesto A. Fernández 2018-10-30 15:06:00 -07:00 committed by Greg Kroah-Hartman
parent b4cb4ecd6a
commit 5f427ca479
1 changed files with 4 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

4
fs/hfsplus/brec.c
View File

@ -427,6 +427,10 @@ static int hfs_brec_update_parent(struct hfs_find_data *fd)
if (new_node) {
__be32 cnid;
if (!new_node->parent) {
hfs_btree_inc_height(tree);
new_node->parent = tree->root;
}
fd->bnode = hfs_bnode_find(tree, new_node->parent);
/* create index key and entry */
hfs_bnode_read_key(new_node, fd->search_key, 14);