ceph: fix recursion between ceph_set_acl() and __ceph_setattr()
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.
Cc: stable@vger.kernel.org # needs backporting for < 4.9
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>
diff --git a/fs/ceph/inode.c b/fs/ceph/inode.c
index d449e1c..d3119fe 100644
--- a/fs/ceph/inode.c
+++ b/fs/ceph/inode.c
@@ -2071,11 +2071,6 @@
if (inode_dirty_flags)
__mark_inode_dirty(inode, inode_dirty_flags);
- if (ia_valid & ATTR_MODE) {
- err = posix_acl_chmod(inode, attr->ia_mode);
- if (err)
- goto out_put;
- }
if (mask) {
req->r_inode = inode;
@@ -2089,13 +2084,11 @@
ceph_cap_string(dirtied), mask);
ceph_mdsc_put_request(req);
- if (mask & CEPH_SETATTR_SIZE)
+ ceph_free_cap_flush(prealloc_cf);
+
+ if (err >= 0 && (mask & CEPH_SETATTR_SIZE))
__ceph_do_pending_vmtruncate(inode);
- ceph_free_cap_flush(prealloc_cf);
- return err;
-out_put:
- ceph_mdsc_put_request(req);
- ceph_free_cap_flush(prealloc_cf);
+
return err;
}
@@ -2114,7 +2107,12 @@
if (err != 0)
return err;
- return __ceph_setattr(inode, attr);
+ err = __ceph_setattr(inode, attr);
+
+ if (err >= 0 && (attr->ia_valid & ATTR_MODE))
+ err = posix_acl_chmod(inode, attr->ia_mode);
+
+ return err;
}
/*