From 54ad9c46c262ce4a603dc7887e37956896a0211d Mon Sep 17 00:00:00 2001 From: Al Viro Date: Wed, 7 Jun 2017 09:42:37 +0100 Subject: itimers: Move compat itimer syscalls to native ones get rid of set_fs(), sanitize compat copyin/copyout. Signed-off-by: Al Viro Signed-off-by: Thomas Gleixner Cc: John Stultz Cc: Peter Zijlstra Link: http://lkml.kernel.org/r/20170607084241.28657-12-viro@ZenIV.linux.org.uk --- kernel/compat.c | 69 +++++++++++++-------------------------------------------- 1 file changed, 16 insertions(+), 53 deletions(-) (limited to 'kernel/compat.c') diff --git a/kernel/compat.c b/kernel/compat.c index 1fb8cf7e691e..c349417d2c40 100644 --- a/kernel/compat.c +++ b/kernel/compat.c @@ -217,65 +217,28 @@ 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(); + struct compat_itimerval v32; - error = do_getitimer(which, &kit); - if (!error && put_compat_itimerval(it, &kit)) - error = -EFAULT; - return error; + 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; + struct compat_itimerval v32; - 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; + 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) -- cgit v1.2.3