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| author | zengtao <prime.zeng@huawei.com> | 2016-02-02 11:38:34 +0800 |
|---|---|---|
| committer | Thomas Gleixner <tglx@linutronix.de> | 2016-02-02 15:24:38 +0100 |
| commit | 0f26922fe5dc5724b1adbbd54b21bad03590b4f3 (patch) | |
| tree | 334714e7872924ab59fe5783d9e6805eb8db9c82 /include/asm-generic/cputime_nsecs.h | |
| parent | 36f90b0a2ddd60823fe193a85e60ff1906c2a9b3 (diff) | |
| download | linux-0f26922fe5dc5724b1adbbd54b21bad03590b4f3.tar.bz2 | |
cputime: Prevent 32bit overflow in time[val|spec]_to_cputime()
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 <prime.zeng@huawei.com>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Cc: <fweisbec@gmail.com>
Cc: stable@vger.kernel.org
Link: http://lkml.kernel.org/r/1454384314-154784-1-git-send-email-prime.zeng@huawei.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Diffstat (limited to 'include/asm-generic/cputime_nsecs.h')
| -rw-r--r-- | include/asm-generic/cputime_nsecs.h | 5 |
1 files changed, 3 insertions, 2 deletions
diff --git a/include/asm-generic/cputime_nsecs.h b/include/asm-generic/cputime_nsecs.h index 0419485891f2..0f1c6f315cdc 100644 --- a/include/asm-generic/cputime_nsecs.h +++ b/include/asm-generic/cputime_nsecs.h @@ -75,7 +75,7 @@ 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) @@ -91,7 +91,8 @@ 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) |