Commit 3a4d44b6 authored by Al Viro's avatar Al Viro Committed by Thomas Gleixner
Browse files

ntp: Move adjtimex related compat syscalls to native counterparts 



Get rid of set_fs() mess and sanitize compat_{get,put}_timex(),
while we are at it.

Signed-off-by: default avatarAl Viro <viro@zeniv.linux.org.uk>
Signed-off-by: default avatarThomas Gleixner <tglx@linutronix.de>
Cc: John Stultz <john.stultz@linaro.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20170607084241.28657-9-viro@ZenIV.linux.org.uk
parent fb923c4a

include/linux/compat.h

+4 −0
Original line number Diff line number Diff line
@@ -128,6 +128,10 @@ struct compat_timex { 
	compat_int_t:32; compat_int_t:32; compat_int_t:32;

};



struct timex;

int compat_get_timex(struct timex *, const struct compat_timex __user *);

int compat_put_timex(struct compat_timex __user *, const struct timex *);



#define _COMPAT_NSIG_WORDS	(_COMPAT_NSIG / _COMPAT_NSIG_BPW)



typedef struct {

kernel/compat.c

+52 −89
Original line number Diff line number Diff line
@@ -30,60 +30,64 @@ 


#include <linux/uaccess.h>



static int compat_get_timex(struct timex *txc, struct compat_timex __user *utp)

{

	memset(txc, 0, sizeof(struct timex));



	if (!access_ok(VERIFY_READ, utp, sizeof(struct compat_timex)) ||

			__get_user(txc->modes, &utp->modes) ||

			__get_user(txc->offset, &utp->offset) ||

			__get_user(txc->freq, &utp->freq) ||

			__get_user(txc->maxerror, &utp->maxerror) ||

			__get_user(txc->esterror, &utp->esterror) ||

			__get_user(txc->status, &utp->status) ||

			__get_user(txc->constant, &utp->constant) ||

			__get_user(txc->precision, &utp->precision) ||

			__get_user(txc->tolerance, &utp->tolerance) ||

			__get_user(txc->time.tv_sec, &utp->time.tv_sec) ||

			__get_user(txc->time.tv_usec, &utp->time.tv_usec) ||

			__get_user(txc->tick, &utp->tick) ||

			__get_user(txc->ppsfreq, &utp->ppsfreq) ||

			__get_user(txc->jitter, &utp->jitter) ||

			__get_user(txc->shift, &utp->shift) ||

			__get_user(txc->stabil, &utp->stabil) ||

			__get_user(txc->jitcnt, &utp->jitcnt) ||

			__get_user(txc->calcnt, &utp->calcnt) ||

			__get_user(txc->errcnt, &utp->errcnt) ||

			__get_user(txc->stbcnt, &utp->stbcnt))

		return -EFAULT;

int compat_get_timex(struct timex *txc, const struct compat_timex __user *utp)

{

	struct compat_timex tx32;



	if (copy_from_user(&tx32, utp, sizeof(struct compat_timex)))

		return -EFAULT;



	txc->modes = tx32.modes;

	txc->offset = tx32.offset;

	txc->freq = tx32.freq;

	txc->maxerror = tx32.maxerror;

	txc->esterror = tx32.esterror;

	txc->status = tx32.status;

	txc->constant = tx32.constant;

	txc->precision = tx32.precision;

	txc->tolerance = tx32.tolerance;

	txc->time.tv_sec = tx32.time.tv_sec;

	txc->time.tv_usec = tx32.time.tv_usec;

	txc->tick = tx32.tick;

	txc->ppsfreq = tx32.ppsfreq;

	txc->jitter = tx32.jitter;

	txc->shift = tx32.shift;

	txc->stabil = tx32.stabil;

	txc->jitcnt = tx32.jitcnt;

	txc->calcnt = tx32.calcnt;

	txc->errcnt = tx32.errcnt;

	txc->stbcnt = tx32.stbcnt;



	return 0;

}



static int compat_put_timex(struct compat_timex __user *utp, struct timex *txc)

{

	if (!access_ok(VERIFY_WRITE, utp, sizeof(struct compat_timex)) ||

			__put_user(txc->modes, &utp->modes) ||

			__put_user(txc->offset, &utp->offset) ||

			__put_user(txc->freq, &utp->freq) ||

			__put_user(txc->maxerror, &utp->maxerror) ||

			__put_user(txc->esterror, &utp->esterror) ||

			__put_user(txc->status, &utp->status) ||

			__put_user(txc->constant, &utp->constant) ||

			__put_user(txc->precision, &utp->precision) ||

			__put_user(txc->tolerance, &utp->tolerance) ||

			__put_user(txc->time.tv_sec, &utp->time.tv_sec) ||

			__put_user(txc->time.tv_usec, &utp->time.tv_usec) ||

			__put_user(txc->tick, &utp->tick) ||

			__put_user(txc->ppsfreq, &utp->ppsfreq) ||

			__put_user(txc->jitter, &utp->jitter) ||

			__put_user(txc->shift, &utp->shift) ||

			__put_user(txc->stabil, &utp->stabil) ||

			__put_user(txc->jitcnt, &utp->jitcnt) ||

			__put_user(txc->calcnt, &utp->calcnt) ||

			__put_user(txc->errcnt, &utp->errcnt) ||

			__put_user(txc->stbcnt, &utp->stbcnt) ||

			__put_user(txc->tai, &utp->tai))

int compat_put_timex(struct compat_timex __user *utp, const struct timex *txc)

{

	struct compat_timex tx32;



	memset(&tx32, 0, sizeof(struct compat_timex));

	tx32.modes = txc->modes;

	tx32.offset = txc->offset;

	tx32.freq = txc->freq;

	tx32.maxerror = txc->maxerror;

	tx32.esterror = txc->esterror;

	tx32.status = txc->status;

	tx32.constant = txc->constant;

	tx32.precision = txc->precision;

	tx32.tolerance = txc->tolerance;

	tx32.time.tv_sec = txc->time.tv_sec;

	tx32.time.tv_usec = txc->time.tv_usec;

	tx32.tick = txc->tick;

	tx32.ppsfreq = txc->ppsfreq;

	tx32.jitter = txc->jitter;

	tx32.shift = txc->shift;

	tx32.stabil = txc->stabil;

	tx32.jitcnt = txc->jitcnt;

	tx32.calcnt = txc->calcnt;

	tx32.errcnt = txc->errcnt;

	tx32.stbcnt = txc->stbcnt;

	tx32.tai = txc->tai;

	if (copy_to_user(utp, &tx32, sizeof(struct compat_timex)))

		return -EFAULT;

	return 0;

}
@@ -705,29 +709,6 @@ COMPAT_SYSCALL_DEFINE2(clock_gettime, clockid_t, which_clock, 
	return err;

}



COMPAT_SYSCALL_DEFINE2(clock_adjtime, clockid_t, which_clock,

		       struct compat_timex __user *, utp)

{

	struct timex txc;

	mm_segment_t oldfs;

	int err, ret;



	err = compat_get_timex(&txc, utp);

	if (err)

		return err;



	oldfs = get_fs();

	set_fs(KERNEL_DS);

	ret = sys_clock_adjtime(which_clock, (struct timex __user *) &txc);

	set_fs(oldfs);



	err = compat_put_timex(utp, &txc);

	if (err)

		return err;



	return ret;

}



COMPAT_SYSCALL_DEFINE2(clock_getres, clockid_t, which_clock,

		       struct compat_timespec __user *, tp)

{
@@ -944,24 +925,6 @@ COMPAT_SYSCALL_DEFINE1(stime, compat_time_t __user *, tptr) 


#endif /* __ARCH_WANT_COMPAT_SYS_TIME */



COMPAT_SYSCALL_DEFINE1(adjtimex, struct compat_timex __user *, utp)

{

	struct timex txc;

	int err, ret;



	err = compat_get_timex(&txc, utp);

	if (err)

		return err;



	ret = do_adjtimex(&txc);



	err = compat_put_timex(utp, &txc);

	if (err)

		return err;



	return ret;

}



#ifdef CONFIG_NUMA

COMPAT_SYSCALL_DEFINE6(move_pages, pid_t, pid, compat_ulong_t, nr_pages,

		       compat_uptr_t __user *, pages32,

kernel/time/posix-stubs.c

+2 −0
Original line number Diff line number Diff line
@@ -28,6 +28,7 @@ asmlinkage long sys_ni_posix_timers(void) 
}



#define SYS_NI(name)  SYSCALL_ALIAS(sys_##name, sys_ni_posix_timers)

#define COMPAT_SYS_NI(name)  SYSCALL_ALIAS(compat_sys_##name, sys_ni_posix_timers)



SYS_NI(timer_create);

SYS_NI(timer_gettime);
@@ -40,6 +41,7 @@ SYS_NI(setitimer); 
#ifdef __ARCH_WANT_SYS_ALARM

SYS_NI(alarm);

#endif

COMPAT_SYS_NI(clock_adjtime);



/*

 * We preserve minimal support for CLOCK_REALTIME and CLOCK_MONOTONIC

kernel/time/posix-timers.c

+27 −0
Original line number Diff line number Diff line
@@ -1018,6 +1018,33 @@ SYSCALL_DEFINE2(clock_adjtime, const clockid_t, which_clock, 
	return err;

}



#ifdef CONFIG_COMPAT



COMPAT_SYSCALL_DEFINE2(clock_adjtime, clockid_t, which_clock,

		       struct compat_timex __user *, utp)

{

	const struct k_clock *kc = clockid_to_kclock(which_clock);

	struct timex ktx;

	int err;



	if (!kc)

		return -EINVAL;

	if (!kc->clock_adj)

		return -EOPNOTSUPP;



	err = compat_get_timex(&ktx, utp);

	if (err)

		return err;



	err = kc->clock_adj(which_clock, &ktx);



	if (err >= 0)

		err = compat_put_timex(utp, &ktx);



	return err;

}

#endif



SYSCALL_DEFINE2(clock_getres, const clockid_t, which_clock,

		struct timespec __user *, tp)

{

kernel/time/time.c

+23 −1
Original line number Diff line number Diff line
@@ -39,6 +39,7 @@ 
#include <linux/ptrace.h>



#include <linux/uaccess.h>

#include <linux/compat.h>

#include <asm/unistd.h>



#include <generated/timeconst.h>
@@ -230,6 +231,27 @@ SYSCALL_DEFINE1(adjtimex, struct timex __user *, txc_p) 
	return copy_to_user(txc_p, &txc, sizeof(struct timex)) ? -EFAULT : ret;

}



#ifdef CONFIG_COMPAT



COMPAT_SYSCALL_DEFINE1(adjtimex, struct compat_timex __user *, utp)

{

	struct timex txc;

	int err, ret;



	err = compat_get_timex(&txc, utp);

	if (err)

		return err;



	ret = do_adjtimex(&txc);



	err = compat_put_timex(utp, &txc);

	if (err)

		return err;



	return ret;

}

#endif



/*

 * Convert jiffies to milliseconds and back.

 *

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