From: Trond Myklebust trond.myklebust@hammerspace.com
commit ac795161c93699d600db16c1a8cc23a65a1eceaf upstream.
If the application sets the O_DIRECTORY flag, and tries to open a regular file, nfs_atomic_open() will punt to doing a regular lookup. If the server then returns a regular file, we will happily return a file descriptor with uninitialised open state.
The fix is to return the expected ENOTDIR error in these cases.
Reported-by: Lyu Tao tao.lyu@epfl.ch Fixes: 0dd2b474d0b6 ("nfs: implement i_op->atomic_open()") Signed-off-by: Trond Myklebust trond.myklebust@hammerspace.com Signed-off-by: Anna Schumaker Anna.Schumaker@Netapp.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- fs/nfs/dir.c | 13 +++++++++++++ 1 file changed, 13 insertions(+)
--- a/fs/nfs/dir.c +++ b/fs/nfs/dir.c @@ -1777,6 +1777,19 @@ out:
no_open: res = nfs_lookup(dir, dentry, lookup_flags); + if (!res) { + inode = d_inode(dentry); + if ((lookup_flags & LOOKUP_DIRECTORY) && inode && + !S_ISDIR(inode->i_mode)) + res = ERR_PTR(-ENOTDIR); + } else if (!IS_ERR(res)) { + inode = d_inode(res); + if ((lookup_flags & LOOKUP_DIRECTORY) && inode && + !S_ISDIR(inode->i_mode)) { + dput(res); + res = ERR_PTR(-ENOTDIR); + } + } if (switched) { d_lookup_done(dentry); if (!res)