From: Al Viro <[email protected]> Turn restart_block.nanosleep.{rmtp,compat_rmtp} into a tagged union (kind = 1 -> native, kind = 2 -> compat, kind = 0 -> nothing) and make the places doing actual copyout handle compat as well as native (that will become a helper in the next commit). Result: compat wrappers, messing with reassignments, etc. are gone.
Signed-off-by: Al Viro <[email protected]> --- include/linux/posix-timers.h | 2 - include/linux/restart_block.h | 7 ++- kernel/compat.c | 131 ----------------------------------------- kernel/time/alarmtimer.c | 16 +++-- kernel/time/hrtimer.c | 38 ++++++++++-- kernel/time/posix-cpu-timers.c | 18 ++++-- kernel/time/posix-stubs.c | 29 ++++++++- kernel/time/posix-timers.c | 32 +++++++--- 8 files changed, 115 insertions(+), 158 deletions(-) diff --git a/include/linux/posix-timers.h b/include/linux/posix-timers.h index 667095dbcd37..29f1b7f09ced 100644 --- a/include/linux/posix-timers.h +++ b/include/linux/posix-timers.h @@ -110,8 +110,6 @@ void posix_cpu_timers_exit_group(struct task_struct *task); void set_process_cpu_timer(struct task_struct *task, unsigned int clock_idx, u64 *newval, u64 *oldval); -long clock_nanosleep_restart(struct restart_block *restart_block); - void update_rlimit_cpu(struct task_struct *task, unsigned long rlim_new); void posixtimer_rearm(struct siginfo *info); diff --git a/include/linux/restart_block.h b/include/linux/restart_block.h index 0d905d8ec553..4509944bd953 100644 --- a/include/linux/restart_block.h +++ b/include/linux/restart_block.h @@ -29,10 +29,13 @@ struct restart_block { /* For nanosleep */ struct { clockid_t clockid; - struct timespec __user *rmtp; + int kind; + union { + struct timespec __user *rmtp; #ifdef CONFIG_COMPAT - struct compat_timespec __user *compat_rmtp; + struct compat_timespec __user *compat_rmtp; #endif + }; u64 expires; } nanosleep; /* For poll */ diff --git a/kernel/compat.c b/kernel/compat.c index cc9ba9d29b47..23afa26f574b 100644 --- a/kernel/compat.c +++ b/kernel/compat.c @@ -213,82 +213,6 @@ int compat_convert_timespec(struct timespec __user **kts, return 0; } -static long compat_nanosleep_restart(struct restart_block *restart) -{ - struct compat_timespec __user *rmtp; - struct timespec rmt; - mm_segment_t oldfs; - long ret; - - restart->nanosleep.rmtp = (struct timespec __user *) &rmt; - oldfs = get_fs(); - set_fs(KERNEL_DS); - ret = hrtimer_nanosleep_restart(restart); - set_fs(oldfs); - - if (ret == -ERESTART_RESTARTBLOCK) { - rmtp = restart->nanosleep.compat_rmtp; - - if (rmtp && compat_put_timespec(&rmt, rmtp)) - return -EFAULT; - } - - return ret; -} - -COMPAT_SYSCALL_DEFINE2(nanosleep, struct compat_timespec __user *, rqtp, - struct compat_timespec __user *, rmtp) -{ - struct timespec tu, rmt; - struct timespec64 tu64; - mm_segment_t oldfs; - long ret; - - if (compat_get_timespec(&tu, rqtp)) - return -EFAULT; - - tu64 = timespec_to_timespec64(tu); - if (!timespec64_valid(&tu64)) - return -EINVAL; - - oldfs = get_fs(); - set_fs(KERNEL_DS); - current->restart_block.nanosleep.rmtp = - rmtp ? (struct timespec __user *)&rmt : NULL; - ret = hrtimer_nanosleep(&tu64, HRTIMER_MODE_REL, CLOCK_MONOTONIC); - set_fs(oldfs); - - /* - * hrtimer_nanosleep() can only return 0 or - * -ERESTART_RESTARTBLOCK here because: - * - * - we call it with HRTIMER_MODE_REL and therefor exclude the - * -ERESTARTNOHAND return path. - * - * - we supply the rmtp argument from the task stack (due to - * the necessary compat conversion. So the update cannot - * fail, which excludes the -EFAULT return path as well. If - * it fails nevertheless we have a bigger problem and wont - * reach this place anymore. - * - * - if the return value is 0, we do not have to update rmtp - * because there is no remaining time. - * - * We check for -ERESTART_RESTARTBLOCK nevertheless if the - * core implementation decides to return random nonsense. - */ - if (ret == -ERESTART_RESTARTBLOCK) { - struct restart_block *restart = ¤t->restart_block; - - restart->fn = compat_nanosleep_restart; - restart->nanosleep.compat_rmtp = rmtp; - - if (rmtp && compat_put_timespec(&rmt, rmtp)) - return -EFAULT; - } - return ret; -} - static inline long get_compat_itimerval(struct itimerval *o, struct compat_itimerval __user *i) { @@ -821,61 +745,6 @@ COMPAT_SYSCALL_DEFINE2(clock_getres, clockid_t, which_clock, return err; } -static long compat_clock_nanosleep_restart(struct restart_block *restart) -{ - long err; - mm_segment_t oldfs; - struct timespec tu; - struct compat_timespec __user *rmtp = restart->nanosleep.compat_rmtp; - - restart->nanosleep.rmtp = (struct timespec __user *) &tu; - oldfs = get_fs(); - set_fs(KERNEL_DS); - err = clock_nanosleep_restart(restart); - set_fs(oldfs); - - if ((err == -ERESTART_RESTARTBLOCK) && rmtp && - compat_put_timespec(&tu, rmtp)) - return -EFAULT; - - if (err == -ERESTART_RESTARTBLOCK) { - restart->fn = compat_clock_nanosleep_restart; - restart->nanosleep.compat_rmtp = rmtp; - } - return err; -} - -COMPAT_SYSCALL_DEFINE4(clock_nanosleep, clockid_t, which_clock, int, flags, - struct compat_timespec __user *, rqtp, - struct compat_timespec __user *, rmtp) -{ - long err; - mm_segment_t oldfs; - struct timespec in, out; - struct restart_block *restart; - - if (compat_get_timespec(&in, rqtp)) - return -EFAULT; - - oldfs = get_fs(); - set_fs(KERNEL_DS); - err = sys_clock_nanosleep(which_clock, flags, - (struct timespec __user *) &in, - (struct timespec __user *) &out); - set_fs(oldfs); - - if ((err == -ERESTART_RESTARTBLOCK) && rmtp && - compat_put_timespec(&out, rmtp)) - return -EFAULT; - - if (err == -ERESTART_RESTARTBLOCK) { - restart = ¤t->restart_block; - restart->fn = compat_clock_nanosleep_restart; - restart->nanosleep.compat_rmtp = rmtp; - } - return err; -} - /* * We currently only need the following fields from the sigevent * structure: sigev_value, sigev_signo, sig_notify and (sometimes diff --git a/kernel/time/alarmtimer.c b/kernel/time/alarmtimer.c index d859a3601ddd..868083ae7434 100644 --- a/kernel/time/alarmtimer.c +++ b/kernel/time/alarmtimer.c @@ -27,6 +27,7 @@ #include <linux/posix-timers.h> #include <linux/workqueue.h> #include <linux/freezer.h> +#include <linux/compat.h> #include "posix-timers.h" @@ -691,7 +692,7 @@ static enum alarmtimer_restart alarmtimer_nsleep_wakeup(struct alarm *alarm, static int alarmtimer_do_nsleep(struct alarm *alarm, ktime_t absexp, enum alarmtimer_type type) { - struct timespec __user *rmtp; + struct restart_block *restart; alarm->data = (void *)current; do { set_current_state(TASK_INTERRUPTIBLE); @@ -709,8 +710,8 @@ static int alarmtimer_do_nsleep(struct alarm *alarm, ktime_t absexp, if (freezing(current)) alarmtimer_freezerset(absexp, type); - rmtp = current->restart_block.nanosleep.rmtp; - if (rmtp) { + restart = ¤t->restart_block; + if (restart->nanosleep.kind) { struct timespec rmt; ktime_t rem; @@ -720,7 +721,14 @@ static int alarmtimer_do_nsleep(struct alarm *alarm, ktime_t absexp, return 0; rmt = ktime_to_timespec(rem); - if (copy_to_user(rmtp, &rmt, sizeof(*rmtp))) +#ifdef CONFIG_COMPAT + if (restart->nanosleep.kind == 2) { + if (compat_put_timespec(&rmt, + restart->nanosleep.compat_rmtp)) + return -EFAULT; + } else +#endif + if (copy_to_user(restart->nanosleep.rmtp, &rmt, sizeof(rmt))) return -EFAULT; } return -ERESTART_RESTARTBLOCK; diff --git a/kernel/time/hrtimer.c b/kernel/time/hrtimer.c index baa7b846b6e3..5534606e3985 100644 --- a/kernel/time/hrtimer.c +++ b/kernel/time/hrtimer.c @@ -51,6 +51,7 @@ #include <linux/sched/debug.h> #include <linux/timer.h> #include <linux/freezer.h> +#include <linux/compat.h> #include <linux/uaccess.h> @@ -1441,7 +1442,7 @@ EXPORT_SYMBOL_GPL(hrtimer_init_sleeper); static int __sched do_nanosleep(struct hrtimer_sleeper *t, enum hrtimer_mode mode) { - struct timespec __user *rmtp; + struct restart_block *restart; hrtimer_init_sleeper(t, current); do { @@ -1461,15 +1462,22 @@ static int __sched do_nanosleep(struct hrtimer_sleeper *t, enum hrtimer_mode mod if (!t->task) return 0; - rmtp = current->restart_block.nanosleep.rmtp; - if (rmtp) { + restart = ¤t->restart_block; + if (restart->nanosleep.kind) { struct timespec rmt; ktime_t rem = hrtimer_expires_remaining(&t->timer); if (rem <= 0) return 0; rmt = ktime_to_timespec(rem); - if (copy_to_user(rmtp, &rmt, sizeof(*rmtp))) +#ifdef CONFIG_COMPAT + if (restart->nanosleep.kind == 2) { + if (compat_put_timespec(&rmt, + restart->nanosleep.compat_rmtp)) + return -EFAULT; + } else +#endif + if (copy_to_user(restart->nanosleep.rmtp, &rmt, sizeof(rmt))) return -EFAULT; } return -ERESTART_RESTARTBLOCK; @@ -1535,10 +1543,32 @@ SYSCALL_DEFINE2(nanosleep, struct timespec __user *, rqtp, if (!timespec64_valid(&tu64)) return -EINVAL; + current->restart_block.nanosleep.kind = rmtp ? 1 : 0; current->restart_block.nanosleep.rmtp = rmtp; return hrtimer_nanosleep(&tu64, HRTIMER_MODE_REL, CLOCK_MONOTONIC); } +#ifdef CONFIG_COMPAT + +COMPAT_SYSCALL_DEFINE2(nanosleep, struct compat_timespec __user *, rqtp, + struct compat_timespec __user *, rmtp) +{ + struct timespec tu; + struct timespec64 tu64; + + if (compat_get_timespec(&tu, rqtp)) + return -EFAULT; + + tu64 = timespec_to_timespec64(tu); + if (!timespec64_valid(&tu64)) + return -EINVAL; + + current->restart_block.nanosleep.kind = rmtp ? 2 : 0; + current->restart_block.nanosleep.compat_rmtp = rmtp; + return hrtimer_nanosleep(&tu64, HRTIMER_MODE_REL, CLOCK_MONOTONIC); +} +#endif + /* * Functions related to boot-time initialization: */ diff --git a/kernel/time/posix-cpu-timers.c b/kernel/time/posix-cpu-timers.c index f999b3ebba7e..b88bc3fc56c5 100644 --- a/kernel/time/posix-cpu-timers.c +++ b/kernel/time/posix-cpu-timers.c @@ -12,6 +12,7 @@ #include <trace/events/timer.h> #include <linux/tick.h> #include <linux/workqueue.h> +#include <linux/compat.h> #include "posix-timers.h" @@ -1243,8 +1244,7 @@ static int do_cpu_nanosleep(const clockid_t which_clock, int flags, timer.it_process = current; if (!error) { static struct itimerspec64 zero_it; - struct restart_block *restart = ¤t->restart_block; - struct timespec __user *rmtp; + struct restart_block *restart; memset(&it, 0, sizeof it); it.it_value = *rqtp; @@ -1311,11 +1311,19 @@ static int do_cpu_nanosleep(const clockid_t which_clock, int flags, /* * Report back to the user the time still remaining. */ - rmtp = restart->nanosleep.rmtp; - if (rmtp) { + restart = ¤t->restart_block; + if (restart->nanosleep.kind) { struct timespec ts; ts = timespec64_to_timespec(it.it_value); - if (copy_to_user(rmtp, &ts, sizeof(*rmtp))) +#ifdef CONFIG_COMPAT + if (restart->nanosleep.kind == 2) { + if (compat_put_timespec(&ts, + restart->nanosleep.compat_rmtp)) + return -EFAULT; + } else +#endif + if (copy_to_user(restart->nanosleep.rmtp, &ts, + sizeof(ts))) return -EFAULT; } restart->nanosleep.expires = timespec64_to_ns(rqtp); diff --git a/kernel/time/posix-stubs.c b/kernel/time/posix-stubs.c index 156a5e6f3bd2..2fe2322d1243 100644 --- a/kernel/time/posix-stubs.c +++ b/kernel/time/posix-stubs.c @@ -17,6 +17,7 @@ #include <linux/ktime.h> #include <linux/timekeeping.h> #include <linux/posix-timers.h> +#include <linux/compat.h> asmlinkage long sys_ni_posix_timers(void) { @@ -117,6 +118,7 @@ SYSCALL_DEFINE4(clock_nanosleep, const clockid_t, which_clock, int, flags, return -EINVAL; if (flags & TIMER_ABSTIME) rmtp = NULL; + current->restart_block.nanosleep.kind = rmtp ? 1 : 0; current->restart_block.nanosleep.rmtp = rmtp; return hrtimer_nanosleep(&t64, flags & TIMER_ABSTIME ? HRTIMER_MODE_ABS : HRTIMER_MODE_REL, @@ -127,8 +129,31 @@ SYSCALL_DEFINE4(clock_nanosleep, const clockid_t, which_clock, int, flags, } #ifdef CONFIG_COMPAT -long clock_nanosleep_restart(struct restart_block *restart_block) +COMPAT_SYSCALL_DEFINE4(clock_nanosleep, clockid_t, which_clock, int, flags, + struct compat_timespec __user *, rqtp, + struct compat_timespec __user *, rmtp) { - return hrtimer_nanosleep_restart(restart_block); + struct timespec64 t64; + struct timespec t; + + switch (which_clock) { + case CLOCK_REALTIME: + case CLOCK_MONOTONIC: + case CLOCK_BOOTTIME: + if (compat_get_timespec(&t, rqtp)) + return -EFAULT; + t64 = timespec_to_timespec64(t); + if (!timespec64_valid(&t64)) + return -EINVAL; + if (flags & TIMER_ABSTIME) + rmtp = NULL; + current->restart_block.nanosleep.kind = rmtp ? 2 : 0; + current->restart_block.nanosleep.compat_rmtp = rmtp; + return hrtimer_nanosleep(&t64, flags & TIMER_ABSTIME ? + HRTIMER_MODE_ABS : HRTIMER_MODE_REL, + which_clock); + default: + return -EINVAL; + } } #endif diff --git a/kernel/time/posix-timers.c b/kernel/time/posix-timers.c index f39ed4bdcc5a..b729e1c0b57d 100644 --- a/kernel/time/posix-timers.c +++ b/kernel/time/posix-timers.c @@ -49,6 +49,7 @@ #include <linux/workqueue.h> #include <linux/export.h> #include <linux/hashtable.h> +#include <linux/compat.h> #include "timekeeping.h" #include "posix-timers.h" @@ -1054,25 +1055,40 @@ SYSCALL_DEFINE4(clock_nanosleep, const clockid_t, which_clock, int, flags, return -EINVAL; if (flags & TIMER_ABSTIME) rmtp = NULL; + current->restart_block.nanosleep.kind = rmtp ? 1 : 0; current->restart_block.nanosleep.rmtp = rmtp; return kc->nsleep(which_clock, flags, &t64); } -/* - * This will restart clock_nanosleep. This is required only by - * compat_clock_nanosleep_restart for now. - */ -long clock_nanosleep_restart(struct restart_block *restart_block) +#ifdef CONFIG_COMPAT +COMPAT_SYSCALL_DEFINE4(clock_nanosleep, clockid_t, which_clock, int, flags, + struct compat_timespec __user *, rqtp, + struct compat_timespec __user *, rmtp) { - clockid_t which_clock = restart_block->nanosleep.clockid; const struct k_clock *kc = clockid_to_kclock(which_clock); + struct timespec64 t64; + struct timespec t; - if (WARN_ON_ONCE(!kc || !kc->nsleep_restart)) + if (!kc) return -EINVAL; + if (!kc->nsleep) + return -ENANOSLEEP_NOTSUP; + + if (compat_get_timespec(&t, rqtp)) + return -EFAULT; - return kc->nsleep_restart(restart_block); + t64 = timespec_to_timespec64(t); + if (!timespec64_valid(&t64)) + return -EINVAL; + if (flags & TIMER_ABSTIME) + rmtp = NULL; + current->restart_block.nanosleep.kind = rmtp ? 2 : 0; + current->restart_block.nanosleep.compat_rmtp = rmtp; + + return kc->nsleep(which_clock, flags, &t64); } +#endif static const struct k_clock clock_realtime = { .clock_getres = posix_get_hrtimer_res, -- 2.11.0
