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>

3 files changed, 14 insertions, 15 deletions

diff --git a/arch/microblaze/include/asm/futex.h b/arch/microblaze/include/asm/futex.h
index 2572077b04eaa..8c90357e59831 100644
--- a/arch/microblaze/include/asm/futex.h
+++ b/arch/microblaze/include/asm/futex.h
@@ -71,7 +71,7 @@ futex_atomic_cmpxchg_inatomic(u32 *uval, u32 __user *uaddr,
 	int ret = 0, cmp;
 	u32 prev;
 
-	if (!access_ok(VERIFY_WRITE, uaddr, sizeof(u32)))
+	if (!access_ok(uaddr, sizeof(u32)))
 		return -EFAULT;
 
 	__asm__ __volatile__ ("1:	lwx	%1, %3, r0;		\
diff --git a/arch/microblaze/include/asm/uaccess.h b/arch/microblaze/include/asm/uaccess.h
index 81f16aadbf9ea..dbfea093a7c7d 100644
--- a/arch/microblaze/include/asm/uaccess.h
+++ b/arch/microblaze/include/asm/uaccess.h
@@ -60,26 +60,25 @@ static inline int ___range_ok(unsigned long addr, unsigned long size)
 #define __range_ok(addr, size) \
 		___range_ok((unsigned long)(addr), (unsigned long)(size))
 
-#define access_ok(type, addr, size) (__range_ok((addr), (size)) == 0)
+#define access_ok(addr, size) (__range_ok((addr), (size)) == 0)
 
 #else
 
-static inline int access_ok(int type, const void __user *addr,
-							unsigned long size)
+static inline int access_ok(const void __user *addr, unsigned long size)
 {
 	if (!size)
 		goto ok;
 
 	if ((get_fs().seg < ((unsigned long)addr)) ||
 			(get_fs().seg < ((unsigned long)addr + size - 1))) {
-		pr_devel("ACCESS fail: %s at 0x%08x (size 0x%x), seg 0x%08x\n",
-			type ? "WRITE" : "READ ", (__force u32)addr, (u32)size,
+		pr_devel("ACCESS fail at 0x%08x (size 0x%x), seg 0x%08x\n",
+			(__force u32)addr, (u32)size,
 			(u32)get_fs().seg);
 		return 0;
 	}
 ok:
-	pr_devel("ACCESS OK: %s at 0x%08x (size 0x%x), seg 0x%08x\n",
-			type ? "WRITE" : "READ ", (__force u32)addr, (u32)size,
+	pr_devel("ACCESS OK at 0x%08x (size 0x%x), seg 0x%08x\n",
+			(__force u32)addr, (u32)size,
 			(u32)get_fs().seg);
 	return 1;
 }
@@ -120,7 +119,7 @@ static inline unsigned long __must_check clear_user(void __user *to,
 							unsigned long n)
 {
 	might_fault();
-	if (unlikely(!access_ok(VERIFY_WRITE, to, n)))
+	if (unlikely(!access_ok(to, n)))
 		return n;
 
 	return __clear_user(to, n);
@@ -174,7 +173,7 @@ extern long __user_bad(void);
 	const typeof(*(ptr)) __user *__gu_addr = (ptr);			\
 	int __gu_err = 0;						\
 									\
-	if (access_ok(VERIFY_READ, __gu_addr, size)) {			\
+	if (access_ok(__gu_addr, size)) {			\
 		switch (size) {						\
 		case 1:							\
 			__get_user_asm("lbu", __gu_addr, __gu_val,	\
@@ -286,7 +285,7 @@ extern long __user_bad(void);
 	typeof(*(ptr)) __user *__pu_addr = (ptr);			\
 	int __pu_err = 0;						\
 									\
-	if (access_ok(VERIFY_WRITE, __pu_addr, size)) {			\
+	if (access_ok(__pu_addr, size)) {			\
 		switch (size) {						\
 		case 1:							\
 			__put_user_asm("sb", __pu_addr, __pu_val,	\
@@ -358,7 +357,7 @@ extern int __strncpy_user(char *to, const char __user *from, int len);
 static inline long
 strncpy_from_user(char *dst, const char __user *src, long count)
 {
-	if (!access_ok(VERIFY_READ, src, 1))
+	if (!access_ok(src, 1))
 		return -EFAULT;
 	return __strncpy_user(dst, src, count);
 }
@@ -372,7 +371,7 @@ extern int __strnlen_user(const char __user *sstr, int len);
 
 static inline long strnlen_user(const char __user *src, long n)
 {
-	if (!access_ok(VERIFY_READ, src, 1))
+	if (!access_ok(src, 1))
 		return 0;
 	return __strnlen_user(src, n);
 }
diff --git a/arch/microblaze/kernel/signal.c b/arch/microblaze/kernel/signal.c
index 97001524ca2d8..0685696349bb4 100644
--- a/arch/microblaze/kernel/signal.c
+++ b/arch/microblaze/kernel/signal.c
@@ -91,7 +91,7 @@ asmlinkage long sys_rt_sigreturn(struct pt_regs *regs)
 	/* Always make any pending restarted system calls return -EINTR */
 	current->restart_block.fn = do_no_restart_syscall;
 
-	if (!access_ok(VERIFY_READ, frame, sizeof(*frame)))
+	if (!access_ok(frame, sizeof(*frame)))
 		goto badframe;
 
 	if (__copy_from_user(&set, &frame->uc.uc_sigmask, sizeof(set)))
@@ -166,7 +166,7 @@ static int setup_rt_frame(struct ksignal *ksig, sigset_t *set,
 
 	frame = get_sigframe(ksig, regs, sizeof(*frame));
 
-	if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame)))
+	if (!access_ok(frame, sizeof(*frame)))
 		return -EFAULT;
 
 	if (ksig->ka.sa.sa_flags & SA_SIGINFO)