Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S934619AbcCIXQk (ORCPT ); Wed, 9 Mar 2016 18:16:40 -0500 Received: from youngberry.canonical.com ([91.189.89.112]:40650 "EHLO youngberry.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S934571AbcCIXQE (ORCPT ); Wed, 9 Mar 2016 18:16:04 -0500 From: Kamal Mostafa To: linux-kernel@vger.kernel.org, stable@vger.kernel.org, kernel-team@lists.ubuntu.com Cc: zengtao , fweisbec@gmail.com, Thomas Gleixner , Kamal Mostafa Subject: [PATCH 3.13.y-ckt 028/138] cputime: Prevent 32bit overflow in time[val|spec]_to_cputime() Date: Wed, 9 Mar 2016 15:12:35 -0800 Message-Id: <1457565265-15195-29-git-send-email-kamal@canonical.com> X-Mailer: git-send-email 2.7.0 In-Reply-To: <1457565265-15195-1-git-send-email-kamal@canonical.com> References: <1457565265-15195-1-git-send-email-kamal@canonical.com> X-Extended-Stable: 3.13 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2180 Lines: 57 3.13.11-ckt36 -stable review patch. If anyone has any objections, please let me know. ---8<------------------------------------------------------------ From: zengtao commit 0f26922fe5dc5724b1adbbd54b21bad03590b4f3 upstream. The datatype __kernel_time_t is u32 on 32bit platform, so its subject to overflows in the timeval/timespec to cputime conversion. Currently the following functions are affected: 1. setitimer() 2. timer_create/timer_settime() 3. sys_clock_nanosleep This can happen on MIPS32 and ARM32 with "Full dynticks CPU time accounting" enabled, which is required for CONFIG_NO_HZ_FULL. Enforce u64 conversion to prevent the overflow. Fixes: 31c1fc818715 ("ARM: Kconfig: allow full nohz CPU accounting") Signed-off-by: zengtao Reviewed-by: Arnd Bergmann Cc: Link: http://lkml.kernel.org/r/1454384314-154784-1-git-send-email-prime.zeng@huawei.com Signed-off-by: Thomas Gleixner Signed-off-by: Kamal Mostafa --- include/asm-generic/cputime_nsecs.h | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/include/asm-generic/cputime_nsecs.h b/include/asm-generic/cputime_nsecs.h index 2c9e62c..f55fb04 100644 --- a/include/asm-generic/cputime_nsecs.h +++ b/include/asm-generic/cputime_nsecs.h @@ -70,7 +70,7 @@ typedef u64 __nocast cputime64_t; */ static inline cputime_t timespec_to_cputime(const struct timespec *val) { - u64 ret = val->tv_sec * NSEC_PER_SEC + val->tv_nsec; + u64 ret = (u64)val->tv_sec * NSEC_PER_SEC + val->tv_nsec; return (__force cputime_t) ret; } static inline void cputime_to_timespec(const cputime_t ct, struct timespec *val) @@ -86,7 +86,8 @@ static inline void cputime_to_timespec(const cputime_t ct, struct timespec *val) */ static inline cputime_t timeval_to_cputime(const struct timeval *val) { - u64 ret = val->tv_sec * NSEC_PER_SEC + val->tv_usec * NSEC_PER_USEC; + u64 ret = (u64)val->tv_sec * NSEC_PER_SEC + + val->tv_usec * NSEC_PER_USEC; return (__force cputime_t) ret; } static inline void cputime_to_timeval(const cputime_t ct, struct timeval *val) -- 2.7.0