From de0f7349a0dd072e54b5fc04c305907b22d28a5f Mon Sep 17 00:00:00 2001

From: Nathan Lynch <nathanl@linux.ibm.com>

Date: Mon, 7 Dec 2020 15:51:33 -0600

Subject: [PATCH] powerpc/rtas: prevent suspend-related sys_rtas use on LE

References: bsc#1181674 ltc#189159

Patch-mainline: v5.11-rc1

Git-commit: de0f7349a0dd072e54b5fc04c305907b22d28a5f

While drmgr has had work in some areas to make its RTAS syscall

interactions endian-neutral, its code for performing partition

migration via the syscall has never worked on LE. While it is able to

complete ibm,suspend-me successfully, it crashes when attempting the

subsequent ibm,update-nodes call.

drmgr is the only known (or plausible) user of ibm,suspend-me,

ibm,update-nodes, and ibm,update-properties, so allow them only in

big-endian configurations.

Signed-off-by: Nathan Lynch <nathanl@linux.ibm.com>

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

Link: https://lore.kernel.org/r/20201207215200.1785968-2-nathanl@linux.ibm.com

Acked-by: Michal Suchanek <msuchanek@suse.de>

---

 arch/powerpc/kernel/rtas.c | 2 ++

 1 file changed, 2 insertions(+)

diff --git a/arch/powerpc/kernel/rtas.c b/arch/powerpc/kernel/rtas.c

index 954f41676f69..4ed64aba37d6 100644

--- a/arch/powerpc/kernel/rtas.c

+++ b/arch/powerpc/kernel/rtas.c

@@ -1050,9 +1050,11 @@ static struct rtas_filter rtas_filters[] __ro_after_init = {

 	{ "set-time-for-power-on", -1, -1, -1, -1, -1 },

 	{ "ibm,set-system-parameter", -1, 1, -1, -1, -1 },

 	{ "set-time-of-day", -1, -1, -1, -1, -1 },

+#ifdef CONFIG_CPU_BIG_ENDIAN

 	{ "ibm,suspend-me", -1, -1, -1, -1, -1 },

 	{ "ibm,update-nodes", -1, 0, -1, -1, -1, 4096 },

 	{ "ibm,update-properties", -1, 0, -1, -1, -1, 4096 },

+#endif

 	{ "ibm,physical-attestation", -1, 0, 1, -1, -1 },

 };

-- 

2.26.2