From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753917AbZBHXXV (ORCPT ); Sun, 8 Feb 2009 18:23:21 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751819AbZBHXXN (ORCPT ); Sun, 8 Feb 2009 18:23:13 -0500 Received: from x35.xmailserver.org ([64.71.152.41]:42493 "EHLO x35.xmailserver.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751319AbZBHXXN (ORCPT ); Sun, 8 Feb 2009 18:23:13 -0500 X-AuthUser: davidel@xmailserver.org Date: Sun, 8 Feb 2009 15:23:11 -0800 (PST) From: Davide Libenzi X-X-Sender: davide@alien.or.mcafeemobile.com To: Linux Kernel Mailing List cc: Michael Kerrisk , Greg KH , Thomas Gleixner , Andrew Morton Subject: [patch 1/2] timerfd add flags check Message-ID: User-Agent: Alpine 1.10 (DEB 962 2008-03-14) X-GPG-FINGRPRINT: CFAE 5BEE FD36 F65E E640 56FE 0974 BF23 270F 474E X-GPG-PUBLIC_KEY: http://www.xmailserver.org/davidel.asc MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 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. Signed-off-by: Davide Libenzi - 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 */