From 6d7e28033f88af1e16f0ed63395fd246791e5857 Mon Sep 17 00:00:00 2001 From: Andi Kleen Date: Tue, 16 Jan 2018 12:52:28 -0800 Subject: [PATCH 083/103] module: Add retpoline tag to VERMAGIC commit 6cfb521ac0d5b97470883ff9b7facae264b7ab12 upstream. 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 Signed-off-by: Greg Kroah-Hartman --- 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 6f8fbcf..a3d0493 100644 --- a/include/linux/vermagic.h +++ b/include/linux/vermagic.h @@ -24,10 +24,16 @@ #ifndef MODULE_ARCH_VERMAGIC #define MODULE_ARCH_VERMAGIC "" #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_ARCH_VERMAGIC \ + MODULE_VERMAGIC_RETPOLINE -- 2.7.4