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authorLinus Torvalds <torvalds@linux-foundation.org>2017-07-06 20:57:13 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2017-07-06 20:57:13 -0700
commitc856863988ebf612d159e55eeddbcd27de63b40d (patch)
tree88ce68d58f66679aabe029a93230280191b58d32 /kernel/compat.c
parent771d3feb4b79f8569bf0033b9075a434d0365fa2 (diff)
parent0d0606060baefdb13d3d80dba1b4c816b0676e16 (diff)
downloadlinux-c856863988ebf612d159e55eeddbcd27de63b40d.tar.gz
Merge branch 'misc.compat' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull misc compat stuff updates from Al Viro:
 "This part is basically untangling various compat stuff. Compat
  syscalls moved to their native counterparts, getting rid of quite a
  bit of double-copying and/or set_fs() uses. A lot of field-by-field
  copyin/copyout killed off.

   - kernel/compat.c is much closer to containing just the
     copyin/copyout of compat structs. Not all compat syscalls are gone
     from it yet, but it's getting there.

   - ipc/compat_mq.c killed off completely.

   - block/compat_ioctl.c cleaned up; floppy compat ioctls moved to
     drivers/block/floppy.c where they belong. Yes, there are several
     drivers that implement some of the same ioctls. Some are m68k and
     one is 32bit-only pmac. drivers/block/floppy.c is the only one in
     that bunch that can be built on biarch"

* 'misc.compat' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  mqueue: move compat syscalls to native ones
  usbdevfs: get rid of field-by-field copyin
  compat_hdio_ioctl: get rid of set_fs()
  take floppy compat ioctls to sodding floppy.c
  ipmi: get rid of field-by-field __get_user()
  ipmi: get COMPAT_IPMICTL_RECEIVE_MSG in sync with the native one
  rt_sigtimedwait(): move compat to native
  select: switch compat_{get,put}_fd_set() to compat_{get,put}_bitmap()
  put_compat_rusage(): switch to copy_to_user()
  sigpending(): move compat to native
  getrlimit()/setrlimit(): move compat to native
  times(2): move compat to native
  compat_{get,put}_bitmap(): use unsafe_{get,put}_user()
  fb_get_fscreeninfo(): don't bother with do_fb_ioctl()
  do_sigaltstack(): lift copying to/from userland into callers
  take compat_sys_old_getrlimit() to native syscall
  trim __ARCH_WANT_SYS_OLD_GETRLIMIT
Diffstat (limited to 'kernel/compat.c')
-rw-r--r--kernel/compat.c267
1 files changed, 49 insertions, 218 deletions
diff --git a/kernel/compat.c b/kernel/compat.c
index 0621c8e1ab72..6f0a0e723a06 100644
--- a/kernel/compat.c
+++ b/kernel/compat.c
@@ -247,53 +247,6 @@ int put_compat_itimerval(struct compat_itimerval __user *o, const struct itimerv
 	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)
-{
-	return compat_jiffies_to_clock_t(clock_t_to_jiffies(x));
-}
-
-COMPAT_SYSCALL_DEFINE1(times, struct compat_tms __user *, tbuf)
-{
-	if (tbuf) {
-		struct tms tms;
-		struct compat_tms tmp;
-
-		do_sys_times(&tms);
-		/* Convert our struct tms to the compat version. */
-		tmp.tms_utime = clock_t_to_compat_clock_t(tms.tms_utime);
-		tmp.tms_stime = clock_t_to_compat_clock_t(tms.tms_stime);
-		tmp.tms_cutime = clock_t_to_compat_clock_t(tms.tms_cutime);
-		tmp.tms_cstime = clock_t_to_compat_clock_t(tms.tms_cstime);
-		if (copy_to_user(tbuf, &tmp, sizeof(tmp)))
-			return -EFAULT;
-	}
-	force_successful_syscall_return();
-	return compat_jiffies_to_clock_t(jiffies);
-}
-
-#ifdef __ARCH_WANT_SYS_SIGPENDING
-
-/*
- * Assumption: old_sigset_t and compat_old_sigset_t are both
- * types that can be passed to put_user()/get_user().
- */
-
-COMPAT_SYSCALL_DEFINE1(sigpending, compat_old_sigset_t __user *, set)
-{
-	old_sigset_t s;
-	long ret;
-	mm_segment_t old_fs = get_fs();
-
-	set_fs(KERNEL_DS);
-	ret = sys_sigpending((old_sigset_t __user *) &s);
-	set_fs(old_fs);
-	if (ret == 0)
-		ret = put_user(s, set);
-	return ret;
-}
-
-#endif
-
 #ifdef __ARCH_WANT_SYS_SIGPROCMASK
 
 /*
@@ -348,94 +301,29 @@ COMPAT_SYSCALL_DEFINE3(sigprocmask, int, how,
 
 #endif
 
-COMPAT_SYSCALL_DEFINE2(setrlimit, unsigned int, resource,
-		       struct compat_rlimit __user *, rlim)
-{
-	struct rlimit r;
-
-	if (!access_ok(VERIFY_READ, rlim, sizeof(*rlim)) ||
-	    __get_user(r.rlim_cur, &rlim->rlim_cur) ||
-	    __get_user(r.rlim_max, &rlim->rlim_max))
-		return -EFAULT;
-
-	if (r.rlim_cur == COMPAT_RLIM_INFINITY)
-		r.rlim_cur = RLIM_INFINITY;
-	if (r.rlim_max == COMPAT_RLIM_INFINITY)
-		r.rlim_max = RLIM_INFINITY;
-	return do_prlimit(current, resource, &r, NULL);
-}
-
-#ifdef COMPAT_RLIM_OLD_INFINITY
-
-COMPAT_SYSCALL_DEFINE2(old_getrlimit, unsigned int, resource,
-		       struct compat_rlimit __user *, rlim)
-{
-	struct rlimit r;
-	int ret;
-	mm_segment_t old_fs = get_fs();
-
-	set_fs(KERNEL_DS);
-	ret = sys_old_getrlimit(resource, (struct rlimit __user *)&r);
-	set_fs(old_fs);
-
-	if (!ret) {
-		if (r.rlim_cur > COMPAT_RLIM_OLD_INFINITY)
-			r.rlim_cur = COMPAT_RLIM_INFINITY;
-		if (r.rlim_max > COMPAT_RLIM_OLD_INFINITY)
-			r.rlim_max = COMPAT_RLIM_INFINITY;
-
-		if (!access_ok(VERIFY_WRITE, rlim, sizeof(*rlim)) ||
-		    __put_user(r.rlim_cur, &rlim->rlim_cur) ||
-		    __put_user(r.rlim_max, &rlim->rlim_max))
-			return -EFAULT;
-	}
-	return ret;
-}
-
-#endif
-
-COMPAT_SYSCALL_DEFINE2(getrlimit, unsigned int, resource,
-		       struct compat_rlimit __user *, rlim)
-{
-	struct rlimit r;
-	int ret;
-
-	ret = do_prlimit(current, resource, NULL, &r);
-	if (!ret) {
-		if (r.rlim_cur > COMPAT_RLIM_INFINITY)
-			r.rlim_cur = COMPAT_RLIM_INFINITY;
-		if (r.rlim_max > COMPAT_RLIM_INFINITY)
-			r.rlim_max = COMPAT_RLIM_INFINITY;
-
-		if (!access_ok(VERIFY_WRITE, rlim, sizeof(*rlim)) ||
-		    __put_user(r.rlim_cur, &rlim->rlim_cur) ||
-		    __put_user(r.rlim_max, &rlim->rlim_max))
-			return -EFAULT;
-	}
-	return ret;
-}
-
 int put_compat_rusage(const struct rusage *r, struct compat_rusage __user *ru)
 {
-	if (!access_ok(VERIFY_WRITE, ru, sizeof(*ru)) ||
-	    __put_user(r->ru_utime.tv_sec, &ru->ru_utime.tv_sec) ||
-	    __put_user(r->ru_utime.tv_usec, &ru->ru_utime.tv_usec) ||
-	    __put_user(r->ru_stime.tv_sec, &ru->ru_stime.tv_sec) ||
-	    __put_user(r->ru_stime.tv_usec, &ru->ru_stime.tv_usec) ||
-	    __put_user(r->ru_maxrss, &ru->ru_maxrss) ||
-	    __put_user(r->ru_ixrss, &ru->ru_ixrss) ||
-	    __put_user(r->ru_idrss, &ru->ru_idrss) ||
-	    __put_user(r->ru_isrss, &ru->ru_isrss) ||
-	    __put_user(r->ru_minflt, &ru->ru_minflt) ||
-	    __put_user(r->ru_majflt, &ru->ru_majflt) ||
-	    __put_user(r->ru_nswap, &ru->ru_nswap) ||
-	    __put_user(r->ru_inblock, &ru->ru_inblock) ||
-	    __put_user(r->ru_oublock, &ru->ru_oublock) ||
-	    __put_user(r->ru_msgsnd, &ru->ru_msgsnd) ||
-	    __put_user(r->ru_msgrcv, &ru->ru_msgrcv) ||
-	    __put_user(r->ru_nsignals, &ru->ru_nsignals) ||
-	    __put_user(r->ru_nvcsw, &ru->ru_nvcsw) ||
-	    __put_user(r->ru_nivcsw, &ru->ru_nivcsw))
+	struct compat_rusage r32;
+	memset(&r32, 0, sizeof(r32));
+	r32.ru_utime.tv_sec = r->ru_utime.tv_sec;
+	r32.ru_utime.tv_usec = r->ru_utime.tv_usec;
+	r32.ru_stime.tv_sec = r->ru_stime.tv_sec;
+	r32.ru_stime.tv_usec = r->ru_stime.tv_usec;
+	r32.ru_maxrss = r->ru_maxrss;
+	r32.ru_ixrss = r->ru_ixrss;
+	r32.ru_idrss = r->ru_idrss;
+	r32.ru_isrss = r->ru_isrss;
+	r32.ru_minflt = r->ru_minflt;
+	r32.ru_majflt = r->ru_majflt;
+	r32.ru_nswap = r->ru_nswap;
+	r32.ru_inblock = r->ru_inblock;
+	r32.ru_oublock = r->ru_oublock;
+	r32.ru_msgsnd = r->ru_msgsnd;
+	r32.ru_msgrcv = r->ru_msgrcv;
+	r32.ru_nsignals = r->ru_nsignals;
+	r32.ru_nvcsw = r->ru_nvcsw;
+	r32.ru_nivcsw = r->ru_nivcsw;
+	if (copy_to_user(ru, &r32, sizeof(r32)))
 		return -EFAULT;
 	return 0;
 }
@@ -565,84 +453,59 @@ int get_compat_sigevent(struct sigevent *event,
 long compat_get_bitmap(unsigned long *mask, const compat_ulong_t __user *umask,
 		       unsigned long bitmap_size)
 {
-	int i, j;
-	unsigned long m;
-	compat_ulong_t um;
 	unsigned long nr_compat_longs;
 
 	/* align bitmap up to nearest compat_long_t boundary */
 	bitmap_size = ALIGN(bitmap_size, BITS_PER_COMPAT_LONG);
+	nr_compat_longs = BITS_TO_COMPAT_LONGS(bitmap_size);
 
 	if (!access_ok(VERIFY_READ, umask, bitmap_size / 8))
 		return -EFAULT;
 
-	nr_compat_longs = BITS_TO_COMPAT_LONGS(bitmap_size);
-
-	for (i = 0; i < BITS_TO_LONGS(bitmap_size); i++) {
-		m = 0;
-
-		for (j = 0; j < sizeof(m)/sizeof(um); j++) {
-			/*
-			 * We dont want to read past the end of the userspace
-			 * bitmap. We must however ensure the end of the
-			 * kernel bitmap is zeroed.
-			 */
-			if (nr_compat_longs) {
-				nr_compat_longs--;
-				if (__get_user(um, umask))
-					return -EFAULT;
-			} else {
-				um = 0;
-			}
-
-			umask++;
-			m |= (long)um << (j * BITS_PER_COMPAT_LONG);
-		}
-		*mask++ = m;
+	user_access_begin();
+	while (nr_compat_longs > 1) {
+		compat_ulong_t l1, l2;
+		unsafe_get_user(l1, umask++, Efault);
+		unsafe_get_user(l2, umask++, Efault);
+		*mask++ = ((unsigned long)l2 << BITS_PER_COMPAT_LONG) | l1;
+		nr_compat_longs -= 2;
 	}
-
+	if (nr_compat_longs)
+		unsafe_get_user(*mask, umask++, Efault);
+	user_access_end();
 	return 0;
+
+Efault:
+	user_access_end();
+	return -EFAULT;
 }
 
 long compat_put_bitmap(compat_ulong_t __user *umask, unsigned long *mask,
 		       unsigned long bitmap_size)
 {
-	int i, j;
-	unsigned long m;
-	compat_ulong_t um;
 	unsigned long nr_compat_longs;
 
 	/* align bitmap up to nearest compat_long_t boundary */
 	bitmap_size = ALIGN(bitmap_size, BITS_PER_COMPAT_LONG);
+	nr_compat_longs = BITS_TO_COMPAT_LONGS(bitmap_size);
 
 	if (!access_ok(VERIFY_WRITE, umask, bitmap_size / 8))
 		return -EFAULT;
 
-	nr_compat_longs = BITS_TO_COMPAT_LONGS(bitmap_size);
-
-	for (i = 0; i < BITS_TO_LONGS(bitmap_size); i++) {
-		m = *mask++;
-
-		for (j = 0; j < sizeof(m)/sizeof(um); j++) {
-			um = m;
-
-			/*
-			 * We dont want to write past the end of the userspace
-			 * bitmap.
-			 */
-			if (nr_compat_longs) {
-				nr_compat_longs--;
-				if (__put_user(um, umask))
-					return -EFAULT;
-			}
-
-			umask++;
-			m >>= 4*sizeof(um);
-			m >>= 4*sizeof(um);
-		}
+	user_access_begin();
+	while (nr_compat_longs > 1) {
+		unsigned long m = *mask++;
+		unsafe_put_user((compat_ulong_t)m, umask++, Efault);
+		unsafe_put_user(m >> BITS_PER_COMPAT_LONG, umask++, Efault);
+		nr_compat_longs -= 2;
 	}
-
+	if (nr_compat_longs)
+		unsafe_put_user((compat_ulong_t)*mask, umask++, Efault);
+	user_access_end();
 	return 0;
+Efault:
+	user_access_end();
+	return -EFAULT;
 }
 
 void
@@ -668,38 +531,6 @@ sigset_to_compat(compat_sigset_t *compat, const sigset_t *set)
 	}
 }
 
-COMPAT_SYSCALL_DEFINE4(rt_sigtimedwait, compat_sigset_t __user *, uthese,
-		struct compat_siginfo __user *, uinfo,
-		struct compat_timespec __user *, uts, compat_size_t, sigsetsize)
-{
-	compat_sigset_t s32;
-	sigset_t s;
-	struct timespec t;
-	siginfo_t info;
-	long ret;
-
-	if (sigsetsize != sizeof(sigset_t))
-		return -EINVAL;
-
-	if (copy_from_user(&s32, uthese, sizeof(compat_sigset_t)))
-		return -EFAULT;
-	sigset_from_compat(&s, &s32);
-
-	if (uts) {
-		if (compat_get_timespec(&t, uts))
-			return -EFAULT;
-	}
-
-	ret = do_sigtimedwait(&s, &info, uts ? &t : NULL);
-
-	if (ret > 0 && uinfo) {
-		if (copy_siginfo_to_user32(uinfo, &info))
-			ret = -EFAULT;
-	}
-
-	return ret;
-}
-
 #ifdef CONFIG_NUMA
 COMPAT_SYSCALL_DEFINE6(move_pages, pid_t, pid, compat_ulong_t, nr_pages,
 		       compat_uptr_t __user *, pages32,