path_openat(): fix double fput()

commit f15133df088ecadd141ea1907f2c96df67c729f0 upstream.

path_openat() jumps to the wrong place after do_tmpfile() - it has
already done path_cleanup() (as part of path_lookupat() called by
do_tmpfile()), so doing that again can lead to double fput().

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
[ luis: backported to 3.16:
  - adjusted context as 3.16 doesn't have path_cleanup() helper,
    introduced by 893b7775a70e ("fs/namei.c: new helper (path_cleanup())") ]
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>

diff --git a/fs/namei.c b/fs/namei.c
index 19ac9c89dbabd19110ea7cca2c1e9b5a737a30a9..15fc3f5a5007f9cfcccac167e2520b472d380d95 100644 (file)
--- a/fs/namei.c
+++ b/fs/namei.c
@@ -3194,7 +3194,7 @@ static struct file *path_openat(int dfd, struct filename *pathname,
 
        if (unlikely(file->f_flags & __O_TMPFILE)) {
                error = do_tmpfile(dfd, pathname, nd, flags, op, file, &opened);
-               goto out;
+               goto out2;
        }
 
        error = path_init(dfd, pathname->name, flags | LOOKUP_PARENT, nd, &base);
@@ -3232,6 +3232,7 @@ out:
                path_put(&nd->root);
        if (base)
                fput(base);
+out2:
        if (!(opened & FILE_OPENED)) {
                BUG_ON(!error);
                put_filp(file);