[PATCH v3 1/3] fs/exec: don't force writing memory access

From: Jann Horn
Date: Wed Nov 02 2016 - 23:05:33 EST


This shouldn't change behavior in any way - at this point, there should be
no non-writable mappings, only the initial stack mapping -, but this change
makes it easier to reason about the correctness of the following commits
that place restrictions on forced memory writes.

Signed-off-by: Jann Horn <jann@xxxxxxxxx>
Reviewed-by: Janis Danisevskis <jdanis@xxxxxxxxxxx>
---
fs/exec.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/fs/exec.c b/fs/exec.c
index 4e497b9ee71e..dbc2dd2f0829 100644
--- a/fs/exec.c
+++ b/fs/exec.c
@@ -191,7 +191,7 @@ static struct page *get_arg_page(struct linux_binprm *bprm, unsigned long pos,
{
struct page *page;
int ret;
- unsigned int gup_flags = FOLL_FORCE;
+ unsigned int gup_flags = 0;

#ifdef CONFIG_STACK_GROWSUP
if (write) {
--
2.1.4