4.9-stable review patch. If anyone has any objections, please let me know.
------------------ From: Yan, Zheng <z...@redhat.com> 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 <leisurelys...@gmail.com> Signed-off-by: "Yan, Zheng" <z...@redhat.com> Reviewed-by: Jeff Layton <jlay...@redhat.com> Tested-by: Luis Henriques <lhenriq...@suse.com> Signed-off-by: Ilya Dryomov <idryo...@gmail.com> Signed-off-by: Greg Kroah-Hartman <gre...@linuxfoundation.org> --- fs/ceph/inode.c | 22 ++++++++++------------ 1 file changed, 10 insertions(+), 12 deletions(-) --- a/fs/ceph/inode.c +++ b/fs/ceph/inode.c @@ -2080,11 +2080,6 @@ int __ceph_setattr(struct inode *inode, 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; @@ -2098,13 +2093,11 @@ int __ceph_setattr(struct inode *inode, ceph_cap_string(dirtied), mask); ceph_mdsc_put_request(req); - if (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); + + if (err >= 0 && (mask & CEPH_SETATTR_SIZE)) + __ceph_do_pending_vmtruncate(inode); + return err; } @@ -2123,7 +2116,12 @@ int ceph_setattr(struct dentry *dentry, 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; } /*
