path: root/fs
diff options
authorDaniel Borkmann <daniel@iogearbox.net>2015-11-05 00:01:51 +0100
committerAl Viro <viro@zeniv.linux.org.uk>2015-11-11 02:04:44 -0500
commit0ee9608c89e81a1ccee52ecb58a7ff040e2522d9 (patch)
tree97cf1ee6fd2d9e07839529c4fb2befc926ad93f7 /fs
parentarm64: fixup for mm renames (diff)
debugfs: fix refcount imbalance in start_creating
In debugfs' start_creating(), we pin the file system to safely access its root. When we failed to create a file, we unpin the file system via failed_creating() to release the mount count and eventually the reference of the vfsmount. However, when we run into an error during lookup_one_len() when still in start_creating(), we only release the parent's mutex but not so the reference on the mount. Looks like it was done in the past, but after splitting portions of __create_file() into start_creating() and end_creating() via 190afd81e4a5 ("debugfs: split the beginning and the end of __create_file() off"), this seemed missed. Noticed during code review. Fixes: 190afd81e4a5 ("debugfs: split the beginning and the end of __create_file() off") Cc: stable@vger.kernel.org # v4.0+ Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Diffstat (limited to 'fs')
1 files changed, 5 insertions, 1 deletions
diff --git a/fs/debugfs/inode.c b/fs/debugfs/inode.c
index 5d8f35f1382a..b7fcc0de0b2f 100644
--- a/fs/debugfs/inode.c
+++ b/fs/debugfs/inode.c
@@ -271,8 +271,12 @@ static struct dentry *start_creating(const char *name, struct dentry *parent)
dentry = ERR_PTR(-EEXIST);
- if (IS_ERR(dentry))
+ if (IS_ERR(dentry)) {
+ simple_release_fs(&debugfs_mount, &debugfs_mount_count);
+ }
return dentry;