Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc-2.6

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc-2.6:
  sparc64: Fix clock event multiplier printf format.
  sparc64: Use clock{source,events}_calc_mult_shift().
  sparc64: Use free_bootmem_late() in mdesc_lmb_free().
  sparc: Add alignment and emulation fault perf events.
  sparc64: Add syscall tracepoint support.
  sparc: Stop trying to be so fancy and use __builtin_{memcpy,memset}()
  sparc: Use __builtin_object_size() to validate the buffer size for copy_from_user()
  sparc64: Add some missing __kprobes annotations to kernel fault paths.
  sparc64: Use kprobes_built_in() to avoid ifdefs in fault_64.c
  sparc: Validate that kprobe address is 4-byte aligned.
  sparc64: Don't specify IRQF_SHARED for LDC interrupts.
  sparc64: Fix stack debugging IRQ stack regression.
  sparc64: Fix overly strict range type matching for PCI devices.

1 files changed, 19 insertions, 4 deletions

diff --git a/arch/sparc/include/asm/uaccess_64.h b/arch/sparc/include/asm/uaccess_64.h
index 9ea271e19c70..dbc141660994 100644
--- a/arch/sparc/include/asm/uaccess_64.h
+++ b/arch/sparc/include/asm/uaccess_64.h
@@ -6,6 +6,7 @@
  */
 
 #ifdef __KERNEL__
+#include <linux/errno.h>
 #include <linux/compiler.h>
 #include <linux/string.h>
 #include <linux/thread_info.h>
@@ -204,6 +205,14 @@ __asm__ __volatile__(							\
 
 extern int __get_user_bad(void);
 
+extern void copy_from_user_overflow(void)
+#ifdef CONFIG_DEBUG_STRICT_USER_COPY_CHECKS
+	__compiletime_error("copy_from_user() buffer size is not provably correct")
+#else
+	__compiletime_warning("copy_from_user() buffer size is not provably correct")
+#endif
+;
+
 extern unsigned long __must_check ___copy_from_user(void *to,
 						    const void __user *from,
 						    unsigned long size);
@@ -212,10 +221,16 @@ extern unsigned long copy_from_user_fixup(void *to, const void __user *from,
 static inline unsigned long __must_check
 copy_from_user(void *to, const void __user *from, unsigned long size)
 {
-	unsigned long ret = ___copy_from_user(to, from, size);
-
-	if (unlikely(ret))
-		ret = copy_from_user_fixup(to, from, size);
+	unsigned long ret = (unsigned long) -EFAULT;
+	int sz = __compiletime_object_size(to);
+
+	if (likely(sz == -1 || sz >= size)) {
+		ret = ___copy_from_user(to, from, size);
+		if (unlikely(ret))
+			ret = copy_from_user_fixup(to, from, size);
+	} else {
+		copy_from_user_overflow();
+	}
 	return ret;
 }
 #define __copy_from_user copy_from_user