Remove 'type' argument from access_ok() function

Nobody has actually used the type (VERIFY_READ vs VERIFY_WRITE) argument
of the user address range verification function since we got rid of the
old racy i386-only code to walk page tables by hand.

It existed because the original 80386 would not honor the write protect
bit when in kernel mode, so you had to do COW by hand before doing any
user access.  But we haven't supported that in a long time, and these
days the 'type' argument is a purely historical artifact.

A discussion about extending 'user_access_begin()' to do the range
checking resulted this patch, because there is no way we're going to
move the old VERIFY_xyz interface to that model.  And it's best done at
the end of the merge window when I've done most of my merges, so let's
just get this done once and for all.

This patch was mostly done with a sed-script, with manual fix-ups for
the cases that weren't of the trivial 'access_ok(VERIFY_xyz' form.

There were a couple of notable cases:

 - csky still had the old "verify_area()" name as an alias.

 - the iter_iov code had magical hardcoded knowledge of the actual
   values of VERIFY_{READ,WRITE} (not that they mattered, since nothing
   really used it)

 - microblaze used the type argument for a debug printout

but other than those oddities this should be a total no-op patch.

I tried to fix up all architectures, did fairly extensive grepping for
access_ok() uses, and the changes are trivial, but I may have missed
something.  Any missed conversion should be trivially fixable, though.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 8 insertions, 8 deletions

diff --git a/kernel/compat.c b/kernel/compat.c
index 089d00d0da9c..705d4ae6c018 100644
--- a/kernel/compat.c
+++ b/kernel/compat.c
@@ -95,28 +95,28 @@ int compat_put_timex(struct compat_timex __user *utp, const struct timex *txc)
 
 static int __compat_get_timeval(struct timeval *tv, const struct old_timeval32 __user *ctv)
 {
-	return (!access_ok(VERIFY_READ, ctv, sizeof(*ctv)) ||
+	return (!access_ok(ctv, sizeof(*ctv)) ||
 			__get_user(tv->tv_sec, &ctv->tv_sec) ||
 			__get_user(tv->tv_usec, &ctv->tv_usec)) ? -EFAULT : 0;
 }
 
 static int __compat_put_timeval(const struct timeval *tv, struct old_timeval32 __user *ctv)
 {
-	return (!access_ok(VERIFY_WRITE, ctv, sizeof(*ctv)) ||
+	return (!access_ok(ctv, sizeof(*ctv)) ||
 			__put_user(tv->tv_sec, &ctv->tv_sec) ||
 			__put_user(tv->tv_usec, &ctv->tv_usec)) ? -EFAULT : 0;
 }
 
 static int __compat_get_timespec(struct timespec *ts, const struct old_timespec32 __user *cts)
 {
-	return (!access_ok(VERIFY_READ, cts, sizeof(*cts)) ||
+	return (!access_ok(cts, sizeof(*cts)) ||
 			__get_user(ts->tv_sec, &cts->tv_sec) ||
 			__get_user(ts->tv_nsec, &cts->tv_nsec)) ? -EFAULT : 0;
 }
 
 static int __compat_put_timespec(const struct timespec *ts, struct old_timespec32 __user *cts)
 {
-	return (!access_ok(VERIFY_WRITE, cts, sizeof(*cts)) ||
+	return (!access_ok(cts, sizeof(*cts)) ||
 			__put_user(ts->tv_sec, &cts->tv_sec) ||
 			__put_user(ts->tv_nsec, &cts->tv_nsec)) ? -EFAULT : 0;
 }
@@ -335,7 +335,7 @@ int get_compat_sigevent(struct sigevent *event,
 		const struct compat_sigevent __user *u_event)
 {
 	memset(event, 0, sizeof(*event));
-	return (!access_ok(VERIFY_READ, u_event, sizeof(*u_event)) ||
+	return (!access_ok(u_event, sizeof(*u_event)) ||
 		__get_user(event->sigev_value.sival_int,
 			&u_event->sigev_value.sival_int) ||
 		__get_user(event->sigev_signo, &u_event->sigev_signo) ||
@@ -354,7 +354,7 @@ long compat_get_bitmap(unsigned long *mask, const compat_ulong_t __user *umask,
 	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))
+	if (!access_ok(umask, bitmap_size / 8))
 		return -EFAULT;
 
 	user_access_begin();
@@ -384,7 +384,7 @@ long compat_put_bitmap(compat_ulong_t __user *umask, unsigned long *mask,
 	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))
+	if (!access_ok(umask, bitmap_size / 8))
 		return -EFAULT;
 
 	user_access_begin();
@@ -438,7 +438,7 @@ void __user *compat_alloc_user_space(unsigned long len)
 
 	ptr = arch_compat_alloc_user_space(len);
 
-	if (unlikely(!access_ok(VERIFY_WRITE, ptr, len)))
+	if (unlikely(!access_ok(ptr, len)))
 		return NULL;
 
 	return ptr;