linux-stable/kernel/time/posix-timers.h
Thomas Gleixner 6fec64e1c9 posix-timers: Make forward callback return s64
The posix timer ti_overrun handling is broken because the forwarding
functions can return a huge number of overruns which does not fit in an
int. As a consequence timer_getoverrun(2) and siginfo::si_overrun can turn
into random number generators.

As a first step to address that let the timer_forward() callbacks return
the full 64 bit value.

Cast it to (int) temporarily until k_itimer::ti_overrun is converted to
64bit and the conversion to user space visible values is sanitized.

Reported-by: Team OWL337 <icytxw@gmail.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: John Stultz <john.stultz@linaro.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Michael Kerrisk <mtk.manpages@gmail.com>
Link: https://lkml.kernel.org/r/20180626132704.922098090@linutronix.de
2018-07-02 11:33:25 +02:00

41 lines
1.6 KiB
C

/* SPDX-License-Identifier: GPL-2.0 */
#define TIMER_RETRY 1
struct k_clock {
int (*clock_getres)(const clockid_t which_clock,
struct timespec64 *tp);
int (*clock_set)(const clockid_t which_clock,
const struct timespec64 *tp);
int (*clock_get)(const clockid_t which_clock,
struct timespec64 *tp);
int (*clock_adj)(const clockid_t which_clock, struct timex *tx);
int (*timer_create)(struct k_itimer *timer);
int (*nsleep)(const clockid_t which_clock, int flags,
const struct timespec64 *);
int (*timer_set)(struct k_itimer *timr, int flags,
struct itimerspec64 *new_setting,
struct itimerspec64 *old_setting);
int (*timer_del)(struct k_itimer *timr);
void (*timer_get)(struct k_itimer *timr,
struct itimerspec64 *cur_setting);
void (*timer_rearm)(struct k_itimer *timr);
s64 (*timer_forward)(struct k_itimer *timr, ktime_t now);
ktime_t (*timer_remaining)(struct k_itimer *timr, ktime_t now);
int (*timer_try_to_cancel)(struct k_itimer *timr);
void (*timer_arm)(struct k_itimer *timr, ktime_t expires,
bool absolute, bool sigev_none);
};
extern const struct k_clock clock_posix_cpu;
extern const struct k_clock clock_posix_dynamic;
extern const struct k_clock clock_process;
extern const struct k_clock clock_thread;
extern const struct k_clock alarm_clock;
int posix_timer_event(struct k_itimer *timr, int si_private);
void common_timer_get(struct k_itimer *timr, struct itimerspec64 *cur_setting);
int common_timer_set(struct k_itimer *timr, int flags,
struct itimerspec64 *new_setting,
struct itimerspec64 *old_setting);
int common_timer_del(struct k_itimer *timer);