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>

1 files changed, 5 insertions, 4 deletions

diff --git a/fs/binfmt_flat.c b/fs/binfmt_flat.c
index 8e812d7a62e0..eb747a266537 100644
--- 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: