[PATCH 4.11 161/197] stackprotector: Increase the per-task stack canarys random range from 32 bits to 64 bits on 64-bit platforms
From: Greg Kroah-Hartman
Date: Tue May 23 2017 - 16:22:12 EST
4.11-stable review patch. If anyone has any objections, please let me know.
------------------
From: Daniel Micay <danielmicay@xxxxxxxxx>
commit 5ea30e4e58040cfd6434c2f33dc3ea76e2c15b05 upstream.
The stack canary is an 'unsigned long' and should be fully initialized to
random data rather than only 32 bits of random data.
Signed-off-by: Daniel Micay <danielmicay@xxxxxxxxx>
Acked-by: Arjan van de Ven <arjan@xxxxxxxxxxxxxxx>
Acked-by: Rik van Riel <riel@xxxxxxxxxx>
Acked-by: Kees Cook <keescook@xxxxxxxxxxxx>
Cc: Arjan van Ven <arjan@xxxxxxxxxxxxxxx>
Cc: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx>
Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Cc: kernel-hardening@xxxxxxxxxxxxxxxxxx
Link: http://lkml.kernel.org/r/20170504133209.3053-1-danielmicay@xxxxxxxxx
Signed-off-by: Ingo Molnar <mingo@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
kernel/fork.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
--- a/kernel/fork.c
+++ b/kernel/fork.c
@@ -536,7 +536,7 @@ static struct task_struct *dup_task_stru
set_task_stack_end_magic(tsk);
#ifdef CONFIG_CC_STACKPROTECTOR
- tsk->stack_canary = get_random_int();
+ tsk->stack_canary = get_random_long();
#endif
/*