From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-wr1-f67.google.com ([209.85.221.67]:36378 "EHLO mail-wr1-f67.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727510AbeJKWFu (ORCPT ); Thu, 11 Oct 2018 18:05:50 -0400 From: Amir Goldstein To: Miklos Szeredi Cc: Al Viro , linux-unionfs@vger.kernel.org, linux-fsdevel@vger.kernel.org Subject: [PATCH v2] vfs: fix FIGETBSZ ioctl on an overlayfs file Date: Thu, 11 Oct 2018 17:38:14 +0300 Message-Id: <20181011143814.14296-1-amir73il@gmail.com> Sender: linux-fsdevel-owner@vger.kernel.org List-ID: Some anon_bdev filesystems (e.g. overlayfs, ceph) don't have s_blocksize set. Returning zero from FIGETBSZ ioctl results in a Floating point exception from the e2fsprogs utility filefrag, which divides the size of the file with the value returned by FIGETBSZ. Fix the interface by returning -EINVAL for these filesystems. Fixes: d1d04ef8572b ("ovl: stack file ops") Signed-off-by: Amir Goldstein --- fs/ioctl.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/fs/ioctl.c b/fs/ioctl.c index 2005529af560..0400297c8d72 100644 --- a/fs/ioctl.c +++ b/fs/ioctl.c @@ -669,6 +669,9 @@ int do_vfs_ioctl(struct file *filp, unsigned int fd, unsigned int cmd, return ioctl_fiemap(filp, arg); case FIGETBSZ: + /* anon_bdev filesystems may not have a block size */ + if (!inode->i_sb->s_blocksize) + return -EINVAL; return put_user(inode->i_sb->s_blocksize, argp); case FICLONE: -- 2.17.1