diff options
| author | Miklos Szeredi <mszeredi@redhat.com> | 2020-12-10 15:33:14 +0100 |
|---|---|---|
| committer | Miklos Szeredi <mszeredi@redhat.com> | 2020-12-10 15:33:14 +0100 |
| commit | 5d069dbe8aaf2a197142558b6fb2978189ba3454 (patch) | |
| tree | 4c9ddb84e8fde7b3120e76c733fca542a5ff7ca2 /fs/fuse/readdir.c | |
| parent | 9d769e6aa2524e1762e3b8681e0ed78f8acf6cad (diff) | |
fuse: fix bad inode
Jan Kara's analysis of the syzbot report (edited):
The reproducer opens a directory on FUSE filesystem, it then attaches
dnotify mark to the open directory. After that a fuse_do_getattr() call
finds that attributes returned by the server are inconsistent, and calls
make_bad_inode() which, among other things does:
inode->i_mode = S_IFREG;
This then confuses dnotify which doesn't tear down its structures
properly and eventually crashes.
Avoid calling make_bad_inode() on a live inode: switch to a private flag on
the fuse inode. Also add the test to ops which the bad_inode_ops would
have caught.
This bug goes back to the initial merge of fuse in 2.6.14...
Reported-by: syzbot+f427adf9324b92652ccc@syzkaller.appspotmail.com
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Tested-by: Jan Kara <jack@suse.cz>
Cc: <stable@vger.kernel.org>
Diffstat (limited to 'fs/fuse/readdir.c')
| -rw-r--r-- | fs/fuse/readdir.c | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/fs/fuse/readdir.c b/fs/fuse/readdir.c index 3b5e91045871..3441ffa740f3 100644 --- a/fs/fuse/readdir.c +++ b/fs/fuse/readdir.c @@ -207,7 +207,7 @@ retry: dput(dentry); goto retry; } - if (is_bad_inode(inode)) { + if (fuse_is_bad(inode)) { dput(dentry); return -EIO; } @@ -568,7 +568,7 @@ int fuse_readdir(struct file *file, struct dir_context *ctx) struct inode *inode = file_inode(file); int err; - if (is_bad_inode(inode)) + if (fuse_is_bad(inode)) return -EIO; mutex_lock(&ff->readdir.lock); |