[PATCH v5 09/15] binfmt_flat: use clear_user() rather than memset() to clear .bss
From: Nicolas Pitre <hidden>
Date: 2016-07-24 15:30:23
Also in:
linux-fsdevel, lkml
Subsystem:
exec & binfmt api, elf, filesystems (vfs and infrastructure), the rest · Maintainers:
Kees Cook, Alexander Viro, Christian Brauner, Linus Torvalds
This is needed on systems with a MMU. Signed-off-by: Nicolas Pitre <redacted> Reviewed-by: Greg Ungerer <gerg@linux-m68k.org> --- fs/binfmt_flat.c | 9 +++++---- 1 file changed, 5 insertions(+), 4 deletions(-)
diff --git a/fs/binfmt_flat.c b/fs/binfmt_flat.c
index 63756ca6a7..92c1530a2c 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:
--
2.7.4