fuse: fix READDIRPLUS skipping an entry

BugLink: http://bugs.launchpad.net/bugs/1731961
commit c6cdd51404b7ac12dd95173ddfc548c59ecf037f upstream.

Marios Titas running a Haskell program noticed a problem with fuse's
readdirplus: when it is interrupted by a signal, it skips one directory
entry.

The reason is that fuse erronously updates ctx->pos after a failed
dir_emit().

The issue originates from the patch adding readdirplus support.

Reported-by: Jakob Unterwurzacher <jakobunt@gmail.com>
Tested-by: Marios Titas <redneb@gmx.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Fixes: 0b05b18381ee ("fuse: implement NFS-like readdirplus support")
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Stefan Bader <stefan.bader@canonical.com>
Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@canonical.com>

diff --git a/fs/fuse/dir.c b/fs/fuse/dir.c
index 8c4d3a48d77d23c8e913d5f4e47412693b2493d7..510241eed919d9c179fb5657d47255c778e38242 100644 (file)
--- a/fs/fuse/dir.c
+++ b/fs/fuse/dir.c
@@ -1312,7 +1312,8 @@ static int parse_dirplusfile(char *buf, size_t nbytes, struct file *file,
                        */
                        over = !dir_emit(ctx, dirent->name, dirent->namelen,
                                       dirent->ino, dirent->type);
-                       ctx->pos = dirent->off;
+                       if (!over)
+                               ctx->pos = dirent->off;
                }
 
                buf += reclen;