From: Jan Kara <jack@xxxxxxx>
commit 85a37983ec69cc9fcd188bc37c4de15ee326355a upstream.
When UDF filesystem is corrupted, hidden system inodes can be linked
into directory hierarchy which is an avenue for further serious
corruption of the filesystem and kernel confusion as noticed by syzbot
fuzzed images. Refuse to access system inodes linked into directory
hierarchy and vice versa.
CC: stable@xxxxxxxxxxxxxxx
Reported-by: syzbot+38695a20b8addcbc1084@xxxxxxxxxxxxxxxxxxxxxxxxx
Signed-off-by: Jan Kara <jack@xxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
fs/udf/inode.c | 7 ++++++-
1 file changed, 6 insertions(+), 1 deletion(-)
--- a/fs/udf/inode.c
+++ b/fs/udf/inode.c
@@ -1897,8 +1897,13 @@ struct inode *__udf_iget(struct super_bl
if (!inode)
return ERR_PTR(-ENOMEM);
- if (!(inode->i_state & I_NEW))
+ if (!(inode->i_state & I_NEW)) {
+ if (UDF_I(inode)->i_hidden != hidden_inode) {
+ iput(inode);
+ return ERR_PTR(-EFSCORRUPTED);
+ }
return inode;
+ }
memcpy(&UDF_I(inode)->i_location, ino, sizeof(struct kernel_lb_addr));
err = udf_read_inode(inode, hidden_inode);
