From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from zeniv.linux.org.uk ([195.92.253.2]:58904 "EHLO ZenIV.linux.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752613AbdJSLvI (ORCPT ); Thu, 19 Oct 2017 07:51:08 -0400 Date: Thu, 19 Oct 2017 12:51:05 +0100 From: Al Viro To: Arnd Bergmann Cc: Jan Kara , Deepa Dinamani , linux-fsdevel@vger.kernel.org, stable@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] isofs: fix timestamps beyond 2027 Message-ID: <20171019115104.GR21978@ZenIV.linux.org.uk> References: <20171019095027.588816-1-arnd@arndb.de> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20171019095027.588816-1-arnd@arndb.de> Sender: linux-fsdevel-owner@vger.kernel.org List-ID: On Thu, Oct 19, 2017 at 11:50:18AM +0200, Arnd Bergmann wrote: > isofs uses a 'char' variable to load the number of years since > 1900 for an inode timestamp. On architectures that use a signed > char type by default, this results in an invalid date for > anything beyond 2027. > > This adds a cast to 'u8' for the year number, which should extend > the shelf life of the file system until 2155. > > This should be backported to all kernels that might still be > in use by that date. > > Cc: stable@vger.kernel.org > Signed-off-by: Arnd Bergmann > --- > fs/isofs/util.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/fs/isofs/util.c b/fs/isofs/util.c > index 005a15cfd30a..f40796c4c6c2 100644 > --- a/fs/isofs/util.c > +++ b/fs/isofs/util.c > @@ -20,7 +20,7 @@ int iso_date(char * p, int flag) > int year, month, day, hour, minute, second, tz; > int crtime; > > - year = p[0]; > + year = (int)(u8)p[0]; This is BS; just turn that char time[7]; in struct stamp into unsigned char time[7]; and adjust iso_date() accordingly. Or make that sucker actually take struct stamp *, while we are at it. And I'd suggest going through the rest of on-disk structures in rock.h and looking for other trouble of that sort.