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Subject[PATCH 2/5] fork,random: use get_random_canary to set tsk->stack_canary
Date
From: Rik van Riel <riel@redhat.com>

Use the ascii-armor canary to prevent unterminated C string overflows
from being able to successfully overwrite the canary, even if they
somehow obtain the canary value.

Inspired by execshield ascii-armor and PaX/grsecurity.

Signed-off-by: Rik van Riel <riel@redhat.com>
---
kernel/fork.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/kernel/fork.c b/kernel/fork.c
index aa1076c5e4a9..b3591e9250a8 100644
--- a/kernel/fork.c
+++ b/kernel/fork.c
@@ -560,7 +560,7 @@ static struct task_struct *dup_task_struct(struct task_struct *orig, int node)
set_task_stack_end_magic(tsk);

#ifdef CONFIG_CC_STACKPROTECTOR
- tsk->stack_canary = get_random_long();
+ tsk->stack_canary = get_random_canary();
#endif

/*
--
2.9.3
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