fs/posix_acl.c: make posix_acl_create() safer and cleaner
authorDan Carpenter <dan.carpenter@oracle.com>
Thu, 18 Jun 2015 23:00:55 +0000 (09:00 +1000)
committerAl Viro <viro@zeniv.linux.org.uk>
Tue, 23 Jun 2015 22:01:07 +0000 (18:01 -0400)
commitc0c3a718e3ab2430a52a60d614b109e5e48e83e2
treed4341a60d055e21310a16bcef68f4c8319f224c7
parent6b6dabc8dcefaf9997ce037c70b32d570ced9d3e
fs/posix_acl.c: make posix_acl_create() safer and cleaner

If posix_acl_create() returns an error code then "*acl" and "*default_acl"
can be uninitialized or point to freed memory.  This is a dangerous thing
to do.  For example, it causes a problem in ocfs2_reflink():

fs/ocfs2/refcounttree.c:4327 ocfs2_reflink()
error: potentially using uninitialized 'default_acl'.

I've re-written this so we set the pointers to NULL at the start.  I've
added a temporary "clone" variable to hold the value of "*acl" until end.
Setting them to NULL means means we don't need the "no_acl" label.  We may
as well remove the "apply_umask" stuff forward and remove that label as
well.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Mark Fasheh <mfasheh@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
fs/posix_acl.c