iv/linux
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

vfs: fix deadlock in file_remove_privs() on overlayfs

Browse Source 
file_remove_privs() is called with inode lock on file_inode(), which
proceeds to calling notify_change() on file->f_path.dentry.  Which triggers
the WARN_ON_ONCE(!inode_is_locked(inode)) in addition to deadlocking later
when ovl_setattr tries to lock the underlying inode again.

Fix this mess by not mixing the layers, but doing everything on underlying
dentry/inode.

Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Fixes: 07a2daab49 ("ovl: Copy up underlying inode's ->i_mode to overlay inode")
Cc: <stable@vger.kernel.org>
This commit is contained in:
Miklos Szeredi 2016-08-03 13:44:27 +02:00
parent 523d939ef9
commit c1892c3776
1 changed files with 3 additions and 3 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

6
fs/inode.c
View File

@ -1740,8 +1740,8 @@ static int __remove_privs(struct dentry *dentry, int kill)
*/
int file_remove_privs(struct file *file)
{
struct dentry *dentry = file->f_path.dentry;
struct inode *inode = d_inode(dentry);
struct dentry *dentry = file_dentry(file);
struct inode *inode = file_inode(file);
int kill;
int error = 0;
@ -1749,7 +1749,7 @@ int file_remove_privs(struct file *file)
if (IS_NOSEC(inode))
return 0;
kill = file_needs_remove_privs(file);
kill = dentry_needs_remove_privs(dentry);
if (kill < 0)
return kill;
if (kill)