2014-02-20 17:44:50

by Kyle McMartin

[permalink] [raw]
Subject: [PATCH] arm/Kconfig.debug: CONFIG_DEBUG_SET_MODULE_RONX and insn patching are mutually exclusive

With both options set, we're seeing an Oops while loading bridge.ko, as
netfilter is trying to use jump labels on the module .text after it's
been marked read-only. I'll cook up a patch to do what X86 does and
remap the page read-write while it's being patched, but for 3.14, we
should mark them as exclusive so others don't hit this crash.

Signed-off-by: Kyle McMartin <[email protected]>

--- a/arch/arm/Kconfig.debug
+++ b/arch/arm/Kconfig.debug
@@ -1197,7 +1197,7 @@ config PID_IN_CONTEXTIDR

config DEBUG_SET_MODULE_RONX
bool "Set loadable kernel module data as NX and text as RO"
- depends on MODULES
+ depends on MODULES && !(JUMP_LABEL || KPROBES)
---help---
This option helps catch unintended modifications to loadable
kernel module's text and read-only data. It also prevents execution