binfmt_flat: use clear_user() rather than memset() to clear .bss

This is needed on systems with a MMU.

Signed-off-by: Nicolas Pitre <nico@linaro.org>
Reviewed-by: Greg Ungerer <gerg@linux-m68k.org>
Signed-off-by: Greg Ungerer <gerg@linux-m68k.org>

diff --git a/fs/binfmt_flat.c b/fs/binfmt_flat.c
index 8e812d7..eb747a2 100644 (file)
--- a/fs/binfmt_flat.c
+++ b/fs/binfmt_flat.c
@@ -795,10 +795,11 @@ static int load_flat_file(struct linux_binprm *bprm,
        flush_icache_range(start_code, end_code);
 
        /* zero the BSS,  BRK and stack areas */
-       memset((void *)(datapos + data_len), 0, bss_len +
-                       (memp + memp_size - stack_len -         /* end brk */
-                       libinfo->lib_list[id].start_brk) +      /* start brk */
-                       stack_len);
+       if (clear_user((void __user *)(datapos + data_len), bss_len +
+                      (memp + memp_size - stack_len -          /* end brk */
+                      libinfo->lib_list[id].start_brk) +       /* start brk */
+                      stack_len))
+               return -EFAULT;
 
        return 0;
 err: