ocfs2: fix ocfs2_init_security_and_acl() to initialize acl correctly
authorJeff Liu <jeff.liu@oracle.com>
Thu, 28 Feb 2013 01:02:48 +0000 (17:02 -0800)
committerLinus Torvalds <torvalds@linux-foundation.org>
Thu, 28 Feb 2013 03:10:09 +0000 (19:10 -0800)
commit32918dd9f19e5960af4cdfa41190bb843fb2247b
tree5f9e131e83017f3854a3435ec618773a328415a4
parent9dc30918b23f4b0d7f7f81be5bda023aea3f6627
ocfs2: fix ocfs2_init_security_and_acl() to initialize acl correctly

We need to re-initialize the security for a new reflinked inode with its
parent dirs if it isn't specified to be preserved for ocfs2_reflink().
However, the code logic is broken at ocfs2_init_security_and_acl()
although ocfs2_init_security_get() succeed.  As a result,
ocfs2_acl_init() does not involked and therefore the default ACL of
parent dir was missing on the new inode.

Note this was introduced by 9d8f13ba3 ("security: new
security_inode_init_security API adds function callback")

To reproduce:

    set default ACL for the parent dir(ocfs2 in this case):
    $ setfacl -m default:user:jeff:rwx ../ocfs2/
    $ getfacl ../ocfs2/
    # file: ../ocfs2/
    # owner: jeff
    # group: jeff
    user::rwx
    group::r-x
    other::r-x
    default:user::rwx
    default:user:jeff:rwx
    default:group::r-x
    default:mask::rwx
    default:other::r-x

    $ touch a
    $ getfacl a
    # file: a
    # owner: jeff
    # group: jeff
    user::rw-
    group::rw-
    other::r--

Before patching, create reflink file b from a, the user
default ACL entry(user:jeff:rwx)was missing:

    $ ./ocfs2_reflink a b
    $ getfacl b
    # file: b
    # owner: jeff
    # group: jeff
    user::rw-
    group::rw-
    other::r--

In this case, the end user can also observed an error message at syslog:

  (ocfs2_reflink,3229,2):ocfs2_init_security_and_acl:7193 ERROR: status = 0

After applying this patch, create reflink file c from a:

    $ ./ocfs2_reflink a c
    $ getfacl c
    # file: c
    # owner: jeff
    # group: jeff
    user::rw-
    user:jeff:rwx #effective:rw-
    group::r-x #effective:r--
    mask::rw-
    other::r--

Test program:
/* Usage: reflink <source> <dest> */
#include <stdio.h>
#include <stdint.h>
#include <stdbool.h>
#include <string.h>
#include <errno.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <sys/ioctl.h>

static int
reflink_file(char const *src_name, char const *dst_name,
     bool preserve_attrs)
{
int fd;

#ifndef REFLINK_ATTR_NONE
#  define REFLINK_ATTR_NONE 0
#endif
#ifndef REFLINK_ATTR_PRESERVE
#  define REFLINK_ATTR_PRESERVE 1
#endif
#ifndef OCFS2_IOC_REFLINK
struct reflink_arguments {
uint64_t old_path;
uint64_t new_path;
uint64_t preserve;
};

#  define OCFS2_IOC_REFLINK _IOW ('o', 4, struct reflink_arguments)
#endif
struct reflink_arguments args = {
.old_path = (unsigned long) src_name,
.new_path = (unsigned long) dst_name,
.preserve = preserve_attrs ? REFLINK_ATTR_PRESERVE :
     REFLINK_ATTR_NONE,
};

fd = open(src_name, O_RDONLY);
if (fd < 0) {
fprintf(stderr, "Failed to open %s: %s\n",
src_name, strerror(errno));
return -1;
}

if (ioctl(fd, OCFS2_IOC_REFLINK, &args) < 0) {
fprintf(stderr, "Failed to reflink %s to %s: %s\n",
src_name, dst_name, strerror(errno));
return -1;
}
}

int
main(int argc, char *argv[])
{
if (argc != 3) {
fprintf(stdout, "Usage: %s source dest\n", argv[0]);
return 1;
}

return reflink_file(argv[1], argv[2], 0);
}

Signed-off-by: Jie Liu <jeff.liu@oracle.com>
Reviewed-by: Tao Ma <boyu.mt@taobao.com>
Cc: Mimi Zohar <zohar@linux.vnet.ibm.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Mark Fasheh <mfasheh@suse.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
fs/ocfs2/xattr.c