[PATCH] Add the __stack_chk_fail() function
GCC emits a call to a __stack_chk_fail() function when the stack canary is
not matching the expected value.
Since this is a bad security issue; lets panic the kernel rather than limping
along; the kernel really can't be trusted anymore when this happens.
Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andi Kleen <ak@suse.de>
CC: Andi Kleen <ak@suse.de>
diff --git a/kernel/panic.c b/kernel/panic.c
index d2db3e2..6ceb664 100644
--- a/kernel/panic.c
+++ b/kernel/panic.c
@@ -271,3 +271,15 @@
{
do_oops_enter_exit();
}
+
+#ifdef CONFIG_CC_STACKPROTECTOR
+/*
+ * Called when gcc's -fstack-protector feature is used, and
+ * gcc detects corruption of the on-stack canary value
+ */
+void __stack_chk_fail(void)
+{
+ panic("stack-protector: Kernel stack is corrupted");
+}
+EXPORT_SYMBOL(__stack_chk_fail);
+#endif