From mboxrd@z Thu Jan 1 00:00:00 1970 From: Michael Kerrisk Subject: Re: [patch 3/4 v2] vfs: utimensat(): fix error checking for {UTIME_NOW,UTIME_OMIT} case Date: Wed, 04 Jun 2008 16:50:59 +0200 Message-ID: <4846ABD3.4000600@gmail.com> References: <484694E7.3080405@gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Cc: lkml , Christoph Hellwig , Miklos Szeredi , viro@zeniv.linux.org.uk, jamie@shareable.org, Ulrich Drepper , linux-fsdevel@vger.kernel.org, Subrata Modak To: Andrew Morton Return-path: Received: from qb-out-0506.google.com ([72.14.204.231]:61828 "EHLO qb-out-0506.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753337AbYFDOvd (ORCPT ); Wed, 4 Jun 2008 10:51:33 -0400 Received: by qb-out-0506.google.com with SMTP id q10so152039qbq.15 for ; Wed, 04 Jun 2008 07:51:30 -0700 (PDT) In-Reply-To: <484694E7.3080405@gmail.com> Sender: linux-fsdevel-owner@vger.kernel.org List-ID: Andrew, This patch improves the indentation of the previous patch. (No other changes). Cheers, Michael --- linux-2.6.26-rc4/fs/utimes.c 2008-06-04 13:36:33.000000000 +0200 +++ linux-2.6.26-rc4-utimensat-fix-v4/fs/utimes.c 2008-06-04 13:35:14.000000000 +0200 @@ -40,14 +40,9 @@ #endif -static bool nsec_special(long nsec) -{ - return nsec == UTIME_OMIT || nsec == UTIME_NOW; -} - static bool nsec_valid(long nsec) { - if (nsec_special(nsec)) + if (nsec == UTIME_OMIT || nsec == UTIME_NOW) return true; return nsec >= 0 && nsec <= 999999999; @@ -106,7 +101,7 @@ times[1].tv_nsec == UTIME_NOW) times = NULL; - /* Don't worry, the checks are done in inode_change_ok() */ + /* In most cases, the checks are done in inode_change_ok() */ newattrs.ia_valid = ATTR_CTIME | ATTR_MTIME | ATTR_ATIME; if (times) { error = -EPERM; @@ -128,15 +123,26 @@ newattrs.ia_mtime.tv_nsec = times[1].tv_nsec; newattrs.ia_valid |= ATTR_MTIME_SET; } - } - /* - * If times is NULL or both times are either UTIME_OMIT or - * UTIME_NOW, then need to check permissions, because - * inode_change_ok() won't do it. - */ - if (!times || (nsec_special(times[0].tv_nsec) && - nsec_special(times[1].tv_nsec))) { + /* + * For the UTIME_OMIT/UTIME_NOW and UTIME_NOW/UTIME_OMIT + * cases, we need to make an extra check that is not done by + * inode_change_ok(). + */ + if (((times[0].tv_nsec == UTIME_NOW && + times[1].tv_nsec == UTIME_OMIT) + || + (times[0].tv_nsec == UTIME_OMIT && + times[1].tv_nsec == UTIME_NOW)) + && !is_owner_or_cap(inode)) + goto mnt_drop_write_and_out; + } else { + + /* + * If times is NULL (or both times are UTIME_NOW), + * then we need to check permissions, because + * inode_change_ok() won't do it. + */ error = -EACCES; if (IS_IMMUTABLE(inode)) goto mnt_drop_write_and_out;