Merge branch 'work.uaccess' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs

Pull uaccess unification updates from Al Viro:
 "This is the uaccess unification pile. It's _not_ the end of uaccess
  work, but the next batch of that will go into the next cycle. This one
  mostly takes copy_from_user() and friends out of arch/* and gets the
  zero-padding behaviour in sync for all architectures.

  Dealing with the nocache/writethrough mess is for the next cycle;
  fortunately, that's x86-only. Same for cleanups in iov_iter.c (I am
  sold on access_ok() in there, BTW; just not in this pile), same for
  reducing __copy_... callsites, strn*... stuff, etc. - there will be a
  pile about as large as this one in the next merge window.

  This one sat in -next for weeks. -3KLoC"

* 'work.uaccess' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (96 commits)
  HAVE_ARCH_HARDENED_USERCOPY is unconditional now
  CONFIG_ARCH_HAS_RAW_COPY_USER is unconditional now
  m32r: switch to RAW_COPY_USER
  hexagon: switch to RAW_COPY_USER
  microblaze: switch to RAW_COPY_USER
  get rid of padding, switch to RAW_COPY_USER
  ia64: get rid of copy_in_user()
  ia64: sanitize __access_ok()
  ia64: get rid of 'segment' argument of __do_{get,put}_user()
  ia64: get rid of 'segment' argument of __{get,put}_user_check()
  ia64: add extable.h
  powerpc: get rid of zeroing, switch to RAW_COPY_USER
  esas2r: don't open-code memdup_user()
  alpha: fix stack smashing in old_adjtimex(2)
  don't open-code kernel_setsockopt()
  mips: switch to RAW_COPY_USER
  mips: get rid of tail-zeroing in primitives
  mips: make copy_from_user() zero tail explicitly
  mips: clean and reorder the forest of macros...
  mips: consolidate __invoke_... wrappers
  ...

3 files changed, 8 insertions, 59 deletions

diff --git a/arch/metag/include/asm/Kbuild b/arch/metag/include/asm/Kbuild
index f9b9df5d6de9..8f940553a579 100644
--- a/arch/metag/include/asm/Kbuild
+++ b/arch/metag/include/asm/Kbuild
@@ -8,6 +8,7 @@ generic-y += dma.h
 generic-y += emergency-restart.h
 generic-y += errno.h
 generic-y += exec.h
+generic-y += extable.h
 generic-y += fb.h
 generic-y += fcntl.h
 generic-y += futex.h
diff --git a/arch/metag/include/asm/uaccess.h b/arch/metag/include/asm/uaccess.h
index 07238b39638c..5ebc2850690e 100644
--- a/arch/metag/include/asm/uaccess.h
+++ b/arch/metag/include/asm/uaccess.h
@@ -4,10 +4,6 @@
 /*
  * User space memory access functions
  */
-#include <linux/sched.h>
-
-#define VERIFY_READ	0
-#define VERIFY_WRITE	1
 
 /*
  * The fs value determines whether argument validity checking should be
@@ -28,7 +24,7 @@
 
 #define segment_eq(a, b)	((a).seg == (b).seg)
 
-#define __kernel_ok (segment_eq(get_fs(), KERNEL_DS))
+#define __kernel_ok (uaccess_kernel())
 /*
  * Explicitly allow NULL pointers here. Parts of the kernel such
  * as readv/writev use access_ok to validate pointers, but want
@@ -51,28 +47,7 @@ static inline int __access_ok(unsigned long addr, unsigned long size)
 #define access_ok(type, addr, size) __access_ok((unsigned long)(addr),	\
 						(unsigned long)(size))
 
-static inline int verify_area(int type, const void *addr, unsigned long size)
-{
-	return access_ok(type, addr, size) ? 0 : -EFAULT;
-}
-
-/*
- * The exception table consists of pairs of addresses: the first is the
- * address of an instruction that is allowed to fault, and the second is
- * the address at which the program should continue.  No registers are
- * modified, so it is entirely up to the continuation code to figure out
- * what to do.
- *
- * All the routines below use bits of fixup code that are out of line
- * with the main instruction path.  This means when everything is well,
- * we don't even have to jump over them.  Further, they do not intrude
- * on our cache or tlb entries.
- */
-struct exception_table_entry {
-	unsigned long insn, fixup;
-};
-
-extern int fixup_exception(struct pt_regs *regs);
+#include <asm/extable.h>
 
 /*
  * These are the main single-value transfer routines.  They automatically
@@ -199,35 +174,8 @@ extern long __must_check strnlen_user(const char __user *src, long count);
 
 extern unsigned long raw_copy_from_user(void *to, const void __user *from,
 					unsigned long n);
-
-static inline unsigned long
-copy_from_user(void *to, const void __user *from, unsigned long n)
-{
-	unsigned long res = n;
-	if (likely(access_ok(VERIFY_READ, from, n)))
-		res = raw_copy_from_user(to, from, n);
-	if (unlikely(res))
-		memset(to + (n - res), 0, res);
-	return res;
-}
-
-#define __copy_from_user(to, from, n) raw_copy_from_user(to, from, n)
-#define __copy_from_user_inatomic __copy_from_user
-
-extern unsigned long __must_check __copy_user(void __user *to,
-					      const void *from,
-					      unsigned long n);
-
-static inline unsigned long copy_to_user(void __user *to, const void *from,
-					 unsigned long n)
-{
-	if (access_ok(VERIFY_WRITE, to, n))
-		return __copy_user(to, from, n);
-	return n;
-}
-
-#define __copy_to_user(to, from, n) __copy_user(to, from, n)
-#define __copy_to_user_inatomic __copy_to_user
+extern unsigned long raw_copy_to_user(void __user *to, const void *from,
+				      unsigned long n);
 
 /*
  * Zero Userspace
diff --git a/arch/metag/lib/usercopy.c b/arch/metag/lib/usercopy.c
index 2792fc621088..e8a4ea83cabb 100644
--- a/arch/metag/lib/usercopy.c
+++ b/arch/metag/lib/usercopy.c
@@ -548,8 +548,8 @@
 		"SUB	%1,	%1,	D0Ar2\n"			\
 		"SUB	%3, %3, D1Ar1\n")
 
-unsigned long __copy_user(void __user *pdst, const void *psrc,
-			  unsigned long n)
+unsigned long raw_copy_to_user(void __user *pdst, const void *psrc,
+			       unsigned long n)
 {
 	register char __user *dst asm ("A0.2") = pdst;
 	register const char *src asm ("A1.2") = psrc;
@@ -654,7 +654,7 @@ unsigned long __copy_user(void __user *pdst, const void *psrc,
 	 */
 	return retn;
 }
-EXPORT_SYMBOL(__copy_user);
+EXPORT_SYMBOL(raw_copy_to_user);
 
 #define __asm_copy_from_user_1(to, from, ret) \
 	__asm_copy_user_cont(to, from, ret,	\