gfs2: Get rid of potential double-freeing in gfs2_create_inode
authorAndreas Gruenbacher <agruenba@redhat.com>
Mon, 26 Nov 2018 17:45:35 +0000 (18:45 +0100)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Sun, 13 Jan 2019 09:01:05 +0000 (10:01 +0100)
commit26538d51467f9255be56a354f103928d2acf5590
tree775632c89e677efe7e7d5adae3ebb94e89caf1fc
parentf69ed08c4197a131949c1ac4ec067ef7d8104bc5
gfs2: Get rid of potential double-freeing in gfs2_create_inode

commit 6ff9b09e00a441599f3aacdf577254455a048bc9 upstream.

In gfs2_create_inode, after setting and releasing the acl / default_acl, the
acl / default_acl pointers are not set to NULL as they should be.  In that
state, when the function reaches label fail_free_acls, gfs2_create_inode will
try to release the same acls again.

Fix that by setting the pointers to NULL after releasing the acls.  Slightly
simplify the logic.  Also, posix_acl_release checks for NULL already, so
there is no need to duplicate those checks here.

Fixes: e01580bf9e4d ("gfs2: use generic posix ACL infrastructure")
Reported-by: Pan Bian <bianpan2016@163.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: stable@vger.kernel.org # v4.9+
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
fs/gfs2/inode.c