From: Al Viro <[email protected]> get rid of set_fs(), sanitize compat copyin/copyout.
Signed-off-by: Al Viro <[email protected]> --- include/linux/compat.h | 4 +++ kernel/compat.c | 71 +++++++++++------------------------------------ kernel/time/itimer.c | 36 ++++++++++++++++++++++++ kernel/time/posix-stubs.c | 2 ++ 4 files changed, 58 insertions(+), 55 deletions(-) diff --git a/include/linux/compat.h b/include/linux/compat.h index ecb8dd261d36..425563c7647b 100644 --- a/include/linux/compat.h +++ b/include/linux/compat.h @@ -94,6 +94,10 @@ struct compat_itimerval { struct compat_timeval it_value; }; +struct itimerval; +int get_compat_itimerval(struct itimerval *, const struct compat_itimerval __user *); +int put_compat_itimerval(struct compat_itimerval __user *, const struct itimerval *); + struct compat_tms { compat_clock_t tms_utime; compat_clock_t tms_stime; diff --git a/kernel/compat.c b/kernel/compat.c index 1fb8cf7e691e..61e3be4cbd2a 100644 --- a/kernel/compat.c +++ b/kernel/compat.c @@ -217,65 +217,26 @@ int compat_convert_timespec(struct timespec __user **kts, return 0; } -static inline long get_compat_itimerval(struct itimerval *o, - struct compat_itimerval __user *i) +int get_compat_itimerval(struct itimerval *o, const struct compat_itimerval __user *i) { - return (!access_ok(VERIFY_READ, i, sizeof(*i)) || - (__get_user(o->it_interval.tv_sec, &i->it_interval.tv_sec) | - __get_user(o->it_interval.tv_usec, &i->it_interval.tv_usec) | - __get_user(o->it_value.tv_sec, &i->it_value.tv_sec) | - __get_user(o->it_value.tv_usec, &i->it_value.tv_usec))); -} - -static inline long put_compat_itimerval(struct compat_itimerval __user *o, - struct itimerval *i) -{ - return (!access_ok(VERIFY_WRITE, o, sizeof(*o)) || - (__put_user(i->it_interval.tv_sec, &o->it_interval.tv_sec) | - __put_user(i->it_interval.tv_usec, &o->it_interval.tv_usec) | - __put_user(i->it_value.tv_sec, &o->it_value.tv_sec) | - __put_user(i->it_value.tv_usec, &o->it_value.tv_usec))); -} - -asmlinkage long sys_ni_posix_timers(void); - -COMPAT_SYSCALL_DEFINE2(getitimer, int, which, - struct compat_itimerval __user *, it) -{ - struct itimerval kit; - int error; - - if (!IS_ENABLED(CONFIG_POSIX_TIMERS)) - return sys_ni_posix_timers(); - - error = do_getitimer(which, &kit); - if (!error && put_compat_itimerval(it, &kit)) - error = -EFAULT; - return error; + struct compat_itimerval v32; + if (copy_from_user(&v32, i, sizeof(struct compat_itimerval))) + return -EFAULT; + o->it_interval.tv_sec = v32.it_interval.tv_sec; + o->it_interval.tv_usec = v32.it_interval.tv_usec; + o->it_value.tv_sec = v32.it_value.tv_sec; + o->it_value.tv_usec = v32.it_value.tv_usec; + return 0; } -COMPAT_SYSCALL_DEFINE3(setitimer, int, which, - struct compat_itimerval __user *, in, - struct compat_itimerval __user *, out) +int put_compat_itimerval(struct compat_itimerval __user *o, const struct itimerval *i) { - struct itimerval kin, kout; - int error; - - if (!IS_ENABLED(CONFIG_POSIX_TIMERS)) - return sys_ni_posix_timers(); - - if (in) { - if (get_compat_itimerval(&kin, in)) - return -EFAULT; - } else - memset(&kin, 0, sizeof(kin)); - - error = do_setitimer(which, &kin, out ? &kout : NULL); - if (error || !out) - return error; - if (put_compat_itimerval(out, &kout)) - return -EFAULT; - return 0; + struct compat_itimerval v32; + v32.it_interval.tv_sec = i->it_interval.tv_sec; + v32.it_interval.tv_usec = i->it_interval.tv_usec; + v32.it_value.tv_sec = i->it_value.tv_sec; + v32.it_value.tv_usec = i->it_value.tv_usec; + return copy_to_user(o, &v32, sizeof(struct compat_itimerval)) ? -EFAULT : 0; } static compat_clock_t clock_t_to_compat_clock_t(clock_t x) diff --git a/kernel/time/itimer.c b/kernel/time/itimer.c index 087d6a1279b8..b23c48dde3da 100644 --- a/kernel/time/itimer.c +++ b/kernel/time/itimer.c @@ -15,6 +15,7 @@ #include <linux/posix-timers.h> #include <linux/hrtimer.h> #include <trace/events/timer.h> +#include <linux/compat.h> #include <linux/uaccess.h> @@ -116,6 +117,18 @@ SYSCALL_DEFINE2(getitimer, int, which, struct itimerval __user *, value) return error; } +#ifdef CONFIG_COMPAT +COMPAT_SYSCALL_DEFINE2(getitimer, int, which, + struct compat_itimerval __user *, it) +{ + struct itimerval kit; + int error = do_getitimer(which, &kit); + if (!error && put_compat_itimerval(it, &kit)) + error = -EFAULT; + return error; +} +#endif + /* * The timer is automagically restarted, when interval != 0 @@ -294,3 +307,26 @@ SYSCALL_DEFINE3(setitimer, int, which, struct itimerval __user *, value, return -EFAULT; return 0; } + +#ifdef CONFIG_COMPAT +COMPAT_SYSCALL_DEFINE3(setitimer, int, which, + struct compat_itimerval __user *, in, + struct compat_itimerval __user *, out) +{ + struct itimerval kin, kout; + int error; + + if (in) { + if (get_compat_itimerval(&kin, in)) + return -EFAULT; + } else + memset(&kin, 0, sizeof(kin)); + + error = do_setitimer(which, &kin, out ? &kout : NULL); + if (error || !out) + return error; + if (put_compat_itimerval(out, &kout)) + return -EFAULT; + return 0; +} +#endif diff --git a/kernel/time/posix-stubs.c b/kernel/time/posix-stubs.c index c6d3cde2edc6..369df2f9a9ff 100644 --- a/kernel/time/posix-stubs.c +++ b/kernel/time/posix-stubs.c @@ -44,6 +44,8 @@ SYS_NI(alarm); COMPAT_SYS_NI(clock_adjtime); COMPAT_SYS_NI(timer_settime); COMPAT_SYS_NI(timer_gettime); +COMPAT_SYS_NI(getitimer); +COMPAT_SYS_NI(setitimer); /* * We preserve minimal support for CLOCK_REALTIME and CLOCK_MONOTONIC -- 2.11.0
