Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754851AbYLOKMq (ORCPT ); Mon, 15 Dec 2008 05:12:46 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1753009AbYLOKMg (ORCPT ); Mon, 15 Dec 2008 05:12:36 -0500 Received: from zeniv.linux.org.uk ([195.92.253.2]:56722 "EHLO ZenIV.linux.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752881AbYLOKMf (ORCPT ); Mon, 15 Dec 2008 05:12:35 -0500 Date: Mon, 15 Dec 2008 10:12:33 +0000 From: Al Viro To: Duane Griffin Cc: linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org, Boaz Harrosh , hch@infradead.org Subject: Re: [PATCH, v2] sysv: ensure link targets are NUL-terminated Message-ID: <20081215101233.GS28946@ZenIV.linux.org.uk> References: <1229022995-9898-3-git-send-email-duaneg@dghda.com> <1229022995-9898-4-git-send-email-duaneg@dghda.com> <1229022995-9898-5-git-send-email-duaneg@dghda.com> <1229022995-9898-6-git-send-email-duaneg@dghda.com> <1229022995-9898-7-git-send-email-duaneg@dghda.com> <1229022995-9898-8-git-send-email-duaneg@dghda.com> <1229022995-9898-9-git-send-email-duaneg@dghda.com> <1229022995-9898-10-git-send-email-duaneg@dghda.com> <1229022995-9898-11-git-send-email-duaneg@dghda.com> <20081211223532.GD18665@dastardly.home.dghda.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20081211223532.GD18665@dastardly.home.dghda.com> User-Agent: Mutt/1.5.17 (2007-11-01) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1157 Lines: 29 On Thu, Dec 11, 2008 at 10:35:32PM +0000, Duane Griffin wrote: > Ensure link targets are NUL-terminated, even if corrupted on-disk. > > Signed-off-by: Duane Griffin > --- > > V2: terminate when the link is read instead of every time it is > followed, as suggested by Dave Kleikamp. > > diff --git a/fs/sysv/inode.c b/fs/sysv/inode.c > index df0d435..1511228 100644 > --- a/fs/sysv/inode.c > +++ b/fs/sysv/inode.c > @@ -163,8 +163,10 @@ void sysv_set_inode(struct inode *inode, dev_t rdev) > if (inode->i_blocks) { > inode->i_op = &sysv_symlink_inode_operations; > inode->i_mapping->a_ops = &sysv_aops; > - } else > + } else { > inode->i_op = &sysv_fast_symlink_inode_operations; > + ((char *) SYSV_I(inode)->i_data)[inode->i_size] = '\0'; If you do it that way, you want to verify that i_size is bounded. Better yet, add a helper for that (taking void *, len, max_len) -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/