From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from icp-osb-irony-out1.external.iinet.net.au ([203.59.1.210]:38239 "EHLO icp-osb-irony-out1.external.iinet.net.au" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725948AbeHTMBR (ORCPT ); Mon, 20 Aug 2018 08:01:17 -0400 Subject: [PATCH] autofs - fix autofs_sbi() does not check super block type From: Ian Kent To: Andrew Morton Cc: linux-fsdevel , autofs mailing list , Kernel Mailing List Date: Mon, 20 Aug 2018 16:37:09 +0800 Message-ID: <153475422934.17131.7563724552005298277.stgit@pluto.themaw.net> MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Sender: linux-fsdevel-owner@vger.kernel.org List-ID: The autofs_sbi() inline function does not check the super block magic number to verify it has been given an autofs super block. Reported-by: syzbot+87c3c541582e56943277@syzkaller.appspotmail.com Signed-off-by: Ian Kent --- fs/autofs/autofs_i.h | 4 +++- fs/autofs/inode.c | 1 - 2 files changed, 3 insertions(+), 2 deletions(-) diff --git a/fs/autofs/autofs_i.h b/fs/autofs/autofs_i.h index 9400a9f6318a..5057b9f0f846 100644 --- a/fs/autofs/autofs_i.h +++ b/fs/autofs/autofs_i.h @@ -26,6 +26,7 @@ #include #include #include +#include /* This is the range of ioctl() numbers we claim as ours */ #define AUTOFS_IOC_FIRST AUTOFS_IOC_READY @@ -124,7 +125,8 @@ struct autofs_sb_info { static inline struct autofs_sb_info *autofs_sbi(struct super_block *sb) { - return (struct autofs_sb_info *)(sb->s_fs_info); + return sb->s_magic != AUTOFS_SUPER_MAGIC ? + NULL : (struct autofs_sb_info *)(sb->s_fs_info); } static inline struct autofs_info *autofs_dentry_ino(struct dentry *dentry) diff --git a/fs/autofs/inode.c b/fs/autofs/inode.c index b51980fc274e..846c052569dd 100644 --- a/fs/autofs/inode.c +++ b/fs/autofs/inode.c @@ -10,7 +10,6 @@ #include #include #include -#include #include "autofs_i.h"