Yan, Zheng 36e0be3187 ceph: fix recursion between ceph_set_acl() and __ceph_setattr()
commit 8179a101eb5f4ef0ac9a915fcea9a9d3109efa90 upstream.

ceph_set_acl() calls __ceph_setattr() if the setacl operation needs
to modify inode's i_mode. __ceph_setattr() updates inode's i_mode,
then calls posix_acl_chmod().

The problem is that __ceph_setattr() calls posix_acl_chmod() before
sending the setattr request. The get_acl() call in posix_acl_chmod()
can trigger a getxattr request. The reply of the getxattr request
can restore inode's i_mode to its old value. The set_acl() call in
posix_acl_chmod() sees old value of inode's i_mode, so it calls
__ceph_setattr() again.

Link: http://tracker.ceph.com/issues/19688
Reported-by: Jerry Lee <leisurelysw24@gmail.com>
Signed-off-by: "Yan, Zheng" <zyan@redhat.com>
Reviewed-by: Jeff Layton <jlayton@redhat.com>
Tested-by: Luis Henriques <lhenriques@suse.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-05-03 08:36:39 -07:00
..
2016-10-15 12:09:13 -07:00
2017-04-27 09:10:37 +02:00
2017-03-12 06:41:47 +01:00
2016-10-30 13:09:42 -04:00
2016-09-27 21:20:53 -04:00
2016-09-27 18:47:38 -04:00
2016-10-13 20:28:22 -07:00
2016-07-26 16:19:19 -07:00