From 6cfb521ac0d5b97470883ff9b7facae264b7ab12 Mon Sep 17 00:00:00 2001 From: Andi Kleen Date: Tue, 16 Jan 2018 12:52:28 -0800 Subject: module: Add retpoline tag to VERMAGIC Add a marker for retpoline to the module VERMAGIC. This catches the case when a non RETPOLINE compiled module gets loaded into a retpoline kernel, making it insecure. It doesn't handle the case when retpoline has been runtime disabled. Even in this case the match of the retcompile status will be enforced. This implies that even with retpoline run time disabled all modules loaded need to be recompiled. Signed-off-by: Andi Kleen Signed-off-by: Thomas Gleixner Reviewed-by: Greg Kroah-Hartman Acked-by: David Woodhouse Cc: rusty@rustcorp.com.au Cc: arjan.van.de.ven@intel.com Cc: jeyu@kernel.org Cc: torvalds@linux-foundation.org Link: https://lkml.kernel.org/r/20180116205228.4890-1-andi@firstfloor.org --- include/linux/vermagic.h | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) diff --git a/include/linux/vermagic.h b/include/linux/vermagic.h index bae807eb2933..853291714ae0 100644 --- a/include/linux/vermagic.h +++ b/include/linux/vermagic.h @@ -31,11 +31,17 @@ #else #define MODULE_RANDSTRUCT_PLUGIN #endif +#ifdef RETPOLINE +#define MODULE_VERMAGIC_RETPOLINE "retpoline " +#else +#define MODULE_VERMAGIC_RETPOLINE "" +#endif #define VERMAGIC_STRING \ UTS_RELEASE " " \ MODULE_VERMAGIC_SMP MODULE_VERMAGIC_PREEMPT \ MODULE_VERMAGIC_MODULE_UNLOAD MODULE_VERMAGIC_MODVERSIONS \ MODULE_ARCH_VERMAGIC \ - MODULE_RANDSTRUCT_PLUGIN + MODULE_RANDSTRUCT_PLUGIN \ + MODULE_VERMAGIC_RETPOLINE -- cgit v1.2.3-59-g8ed1b