frv: fix mmap2 error handling

Fix the error handling in sys_mmap2().  Currently, if the pgoff check
fails, fput() might have to be called (which it isn't), so do the pgoff
check first, before fget() is called.

Signed-off-by: David Howells <dhowells@redhat.com>
Reported-by: Julia Lawall <julia@diku.dk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

arch/frv/kernel/sys_frv.c

@@ -35,6 +35,15 @@ asmlinkage long sys_mmap2(unsigned long addr, unsigned long len,
 	int error = -EBADF;
 	struct file * file = NULL;
 
+	/* As with sparc32, make sure the shift for mmap2 is constant
+	   (12), no matter what PAGE_SIZE we have.... */
+
+	/* But unlike sparc32, don't just silently break if we're
+	   trying to map something we can't */
+	if (pgoff & ((1 << (PAGE_SHIFT - 12)) - 1))
+		return -EINVAL;
+	pgoff >>= PAGE_SHIFT - 12;
+
 	flags &= ~(MAP_EXECUTABLE | MAP_DENYWRITE);
 	if (!(flags & MAP_ANONYMOUS)) {
 		file = fget(fd);
@@ -42,16 +51,6 @@ asmlinkage long sys_mmap2(unsigned long addr, unsigned long len,
 			goto out;
 	}
 
-	/* As with sparc32, make sure the shift for mmap2 is constant
-	   (12), no matter what PAGE_SIZE we have.... */
-
-	/* But unlike sparc32, don't just silently break if we're
-	   trying to map something we can't */
-	if (pgoff & ((1<<(PAGE_SHIFT-12))-1))
-		return -EINVAL;
-
-	pgoff >>= (PAGE_SHIFT - 12);
-
 	down_write(&current->mm->mmap_sem);
 	error = do_mmap_pgoff(file, addr, len, prot, flags, pgoff);
 	up_write(&current->mm->mmap_sem);