From: Daniel Micay <danielmicay@gmail.com>
Date: Thu, 4 May 2017 13:32:09 +0000 (-0400)
Subject: stackprotector: Increase the per-task stack canary's random range from 32 bits to... 
X-Git-Tag: release-20171130_firefly~4^2~100^2~1^2~4^2~43
X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=2ff1edbbb29b11ca0cce7704c680ae88c3d78568;p=firefly-linux-kernel-4.4.55.git

stackprotector: Increase the per-task stack canary's random range from 32 bits to 64 bits on 64-bit platforms

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@gmail.com>
Acked-by: Arjan van de Ven <arjan@linux.intel.com>
Acked-by: Rik van Riel <riel@redhat.com>
Acked-by: Kees Cook <keescook@chromium.org>
Cc: Arjan van Ven <arjan@linux.intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: kernel-hardening@lists.openwall.com
Cc: stable@vger.kernel.org
Link: http://lkml.kernel.org/r/20170504133209.3053-1-danielmicay@gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---

diff --git a/kernel/fork.c b/kernel/fork.c
index 0ee630f3ad4b..68cfda1c1800 100644
--- a/kernel/fork.c
+++ b/kernel/fork.c
@@ -368,7 +368,7 @@ 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_int();
+	tsk->stack_canary = get_random_long();
 #endif
 
 	/*