From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754060AbZBHXiV (ORCPT ); Sun, 8 Feb 2009 18:38:21 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751391AbZBHXiN (ORCPT ); Sun, 8 Feb 2009 18:38:13 -0500 Received: from wa-out-1112.google.com ([209.85.146.183]:17032 "EHLO wa-out-1112.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751319AbZBHXiM (ORCPT ); Sun, 8 Feb 2009 18:38:12 -0500 DomainKey-Signature: a=rsa-sha1; c=nofws; d=googlemail.com; s=gamma; h=mime-version:reply-to:in-reply-to:references:date:message-id :subject:from:to:cc:content-type:content-transfer-encoding; b=fF7+9IrFe/3Oj/Ydcg0C9JeY3dFNQ2hW3NL3SJ07yZoXXJKTyfUa55Bn15/e/+EK/y Gv86fRghzPe356ZbfQzrIN9In+9urOYCbjdZQc1pSXhXHBlmK7qicxezuZNBMni4GHpq 4D0BsKYriR4iBO/krFzdlgvvx+mymQ9vLDpFA= MIME-Version: 1.0 Reply-To: mtk.manpages@gmail.com In-Reply-To: References: Date: Mon, 9 Feb 2009 12:38:10 +1300 Message-ID: Subject: Re: [patch 1/2] timerfd add flags check From: Michael Kerrisk To: Davide Libenzi Cc: Linux Kernel Mailing List , Greg KH , Thomas Gleixner , Andrew Morton Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Feb 9, 2009 at 12:23 PM, Davide Libenzi wrote: > Like Michael requested, this patch adds a missing check for valid flags in > timerfd_settime(), and make it return EINVAL in case some extra bits are > set. If this is or not a -stable thing, it Greg decision. > Should be queued by Andrew for .30, unless -stable and Linus decide to > get it before, like Michael suggested. If this is to be any use to userland apps that want to check flag support (perhaps it is too late already), then the sooner we get it into the kernel the better: 2.6.29 would be good; earlier stables as well would be even better. Acked-by: Michael Kerrisk > - Davide > > > --- > fs/timerfd.c | 12 ++++++------ > include/linux/timerfd.h | 17 ++++++++++++++--- > 2 files changed, 20 insertions(+), 9 deletions(-) > > Index: linux-2.6.mod/fs/timerfd.c > =================================================================== > --- linux-2.6.mod.orig/fs/timerfd.c 2009-02-08 14:51:12.000000000 -0800 > +++ linux-2.6.mod/fs/timerfd.c 2009-02-08 14:55:32.000000000 -0800 > @@ -186,10 +186,9 @@ SYSCALL_DEFINE2(timerfd_create, int, clo > BUILD_BUG_ON(TFD_CLOEXEC != O_CLOEXEC); > BUILD_BUG_ON(TFD_NONBLOCK != O_NONBLOCK); > > - if (flags & ~(TFD_CLOEXEC | TFD_NONBLOCK)) > - return -EINVAL; > - if (clockid != CLOCK_MONOTONIC && > - clockid != CLOCK_REALTIME) > + if ((flags & ~TFD_CREATE_FLAGS) || > + (clockid != CLOCK_MONOTONIC && > + clockid != CLOCK_REALTIME)) > return -EINVAL; > > ctx = kzalloc(sizeof(*ctx), GFP_KERNEL); > @@ -201,7 +200,7 @@ SYSCALL_DEFINE2(timerfd_create, int, clo > hrtimer_init(&ctx->tmr, clockid, HRTIMER_MODE_ABS); > > ufd = anon_inode_getfd("[timerfd]", &timerfd_fops, ctx, > - flags & (O_CLOEXEC | O_NONBLOCK)); > + flags & TFD_SHARED_FCNTL_FLAGS); > if (ufd < 0) > kfree(ctx); > > @@ -219,7 +218,8 @@ SYSCALL_DEFINE4(timerfd_settime, int, uf > if (copy_from_user(&ktmr, utmr, sizeof(ktmr))) > return -EFAULT; > > - if (!timespec_valid(&ktmr.it_value) || > + if ((flags & ~TFD_SETTIME_FLAGS) || > + !timespec_valid(&ktmr.it_value) || > !timespec_valid(&ktmr.it_interval)) > return -EINVAL; > > Index: linux-2.6.mod/include/linux/timerfd.h > =================================================================== > --- linux-2.6.mod.orig/include/linux/timerfd.h 2009-02-08 14:51:12.000000000 -0800 > +++ linux-2.6.mod/include/linux/timerfd.h 2009-02-08 14:53:00.000000000 -0800 > @@ -11,13 +11,24 @@ > /* For O_CLOEXEC and O_NONBLOCK */ > #include > > -/* Flags for timerfd_settime. */ > +/* > + * CAREFUL: Check include/asm-generic/fcntl.h when defining > + * new flags, since they might collide with O_* ones. We want > + * to re-use O_* flags that couldn't possibly have a meaning > + * from eventfd, in order to leave a free define-space for > + * shared O_* flags. > + */ > #define TFD_TIMER_ABSTIME (1 << 0) > - > -/* Flags for timerfd_create. */ > #define TFD_CLOEXEC O_CLOEXEC > #define TFD_NONBLOCK O_NONBLOCK > > +#define TFD_SHARED_FCNTL_FLAGS (TFD_CLOEXEC | TFD_NONBLOCK) > +/* Flags for timerfd_create. */ > +#define TFD_CREATE_FLAGS TFD_SHARED_FCNTL_FLAGS > +/* Flags for timerfd_settime. */ > +#define TFD_SETTIME_FLAGS TFD_TIMER_ABSTIME > +#define TFD_FLAGS_SET (TFD_SHARED_FCNTL_FLAGS | TFD_TIMER_ABSTIME) > + > > #endif /* _LINUX_TIMERFD_H */ > > -- Michael Kerrisk Linux man-pages maintainer; http://www.kernel.org/doc/man-pages/ git://git.kernel.org/pub/scm/docs/man-pages/man-pages.git man-pages online: http://www.kernel.org/doc/man-pages/online_pages.html Found a bug? http://www.kernel.org/doc/man-pages/reporting_bugs.html