Subject: linux-next: build warning after merge of the overlayfs tree

From: Stephen Rothwell <[email-masked]>
Date: Tue, 22 Nov 2016 11:19:39 +1100

Hi Miklos,

After merging the overlayfs tree, today's linux-next build (powerpc
ppc64_defconfig) produced this warning:

In file included from fs/overlayfs/dir.c:20:0:
fs/overlayfs/dir.c: In function 'ovl_set_redirect':
fs/overlayfs/overlayfs.h:92:6: warning: 'ret' may be used uninitialized in this function [-Wmaybe-uninitialized]
  int err = vfs_setxattr(dentry, name, value, size, flags);
      ^
fs/overlayfs/dir.c:788:14: note: 'ret' was declared here
  char *buf, *ret;
              ^

Introduced by commit

  496654b0792e ("ovl: redirect on rename-dir")

This is not necessarily a false positive (although is is a confusing
message): if the kmalloc of "buf" fails and samedir was not set in
ovl_get_redirect(), then "return ret" will be executed but "ret" has
not been set.

-- 
Cheers,
Stephen Rothwell