Patch "powerpc/powernv: Set or clear security feature flags" has been added to the 4.4-stable tree

[<gregkh@linuxfoundation.org>]

This is a note to let you know that I've just added the patch titled

    powerpc/powernv: Set or clear security feature flags

to the 4.4-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     powerpc-powernv-set-or-clear-security-feature-flags.patch
and it can be found in the queue-4.4 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@vger.kernel.org> know about it.


From foo@baz Mon 29 Apr 2019 11:38:37 AM CEST
From: Michael Ellerman <mpe@ellerman.id.au>
Date: Mon, 22 Apr 2019 00:19:58 +1000
Subject: powerpc/powernv: Set or clear security feature flags
To: stable@vger.kernel.org, gregkh@linuxfoundation.org
Cc: linuxppc-dev@ozlabs.org, diana.craciun@nxp.com, msuchanek@suse.de, npiggin@gmail.com, christophe.leroy@c-s.fr
Message-ID: <20190421142037.21881-14-mpe@ellerman.id.au>

From: Michael Ellerman <mpe@ellerman.id.au>

commit 77addf6e95c8689e478d607176b399a6242a777e upstream.

Now that we have feature flags for security related things, set or
clear them based on what we see in the device tree provided by
firmware.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 arch/powerpc/platforms/powernv/setup.c |   56 +++++++++++++++++++++++++++++++++
 1 file changed, 56 insertions(+)

--- a/arch/powerpc/platforms/powernv/setup.c
+++ b/arch/powerpc/platforms/powernv/setup.c
@@ -37,9 +37,63 @@
 #include <asm/smp.h>
 #include <asm/tm.h>
 #include <asm/setup.h>
+#include <asm/security_features.h>
 
 #include "powernv.h"
 
+
+static bool fw_feature_is(const char *state, const char *name,
+			  struct device_node *fw_features)
+{
+	struct device_node *np;
+	bool rc = false;
+
+	np = of_get_child_by_name(fw_features, name);
+	if (np) {
+		rc = of_property_read_bool(np, state);
+		of_node_put(np);
+	}
+
+	return rc;
+}
+
+static void init_fw_feat_flags(struct device_node *np)
+{
+	if (fw_feature_is("enabled", "inst-spec-barrier-ori31,31,0", np))
+		security_ftr_set(SEC_FTR_SPEC_BAR_ORI31);
+
+	if (fw_feature_is("enabled", "fw-bcctrl-serialized", np))
+		security_ftr_set(SEC_FTR_BCCTRL_SERIALISED);
+
+	if (fw_feature_is("enabled", "inst-spec-barrier-ori31,31,0", np))
+		security_ftr_set(SEC_FTR_L1D_FLUSH_ORI30);
+
+	if (fw_feature_is("enabled", "inst-l1d-flush-trig2", np))
+		security_ftr_set(SEC_FTR_L1D_FLUSH_TRIG2);
+
+	if (fw_feature_is("enabled", "fw-l1d-thread-split", np))
+		security_ftr_set(SEC_FTR_L1D_THREAD_PRIV);
+
+	if (fw_feature_is("enabled", "fw-count-cache-disabled", np))
+		security_ftr_set(SEC_FTR_COUNT_CACHE_DISABLED);
+
+	/*
+	 * The features below are enabled by default, so we instead look to see
+	 * if firmware has *disabled* them, and clear them if so.
+	 */
+	if (fw_feature_is("disabled", "speculation-policy-favor-security", np))
+		security_ftr_clear(SEC_FTR_FAVOUR_SECURITY);
+
+	if (fw_feature_is("disabled", "needs-l1d-flush-msr-pr-0-to-1", np))
+		security_ftr_clear(SEC_FTR_L1D_FLUSH_PR);
+
+	if (fw_feature_is("disabled", "needs-l1d-flush-msr-hv-1-to-0", np))
+		security_ftr_clear(SEC_FTR_L1D_FLUSH_HV);
+
+	if (fw_feature_is("disabled", "needs-spec-barrier-for-bound-checks", np))
+		security_ftr_clear(SEC_FTR_BNDS_CHK_SPEC_BAR);
+}
+
 static void pnv_setup_rfi_flush(void)
 {
 	struct device_node *np, *fw_features;
@@ -55,6 +109,8 @@ static void pnv_setup_rfi_flush(void)
 	of_node_put(np);
 
 	if (fw_features) {
+		init_fw_feat_flags(fw_features);
+
 		np = of_get_child_by_name(fw_features, "inst-l1d-flush-trig2");
 		if (np && of_property_read_bool(np, "enabled"))
 			type = L1D_FLUSH_MTTRIG;


Patches currently in stable-queue which might be from mpe@ellerman.id.au are

queue-4.4/powerpc-64s-add-support-for-a-store-forwarding-barrier-at-kernel-entry-exit.patch
queue-4.4/powerpc-64-make-stf-barrier-ppc_book3s_64-specific.patch
queue-4.4/powerpc-pseries-set-or-clear-security-feature-flags.patch
queue-4.4/powerpc-fsl-fix-spectre_v2-mitigations-reporting.patch
queue-4.4/powerpc-64s-patch-barrier_nospec-in-modules.patch
queue-4.4/powerpc-pseries-support-firmware-disable-of-rfi-flush.patch
queue-4.4/powerpc-rfi-flush-call-setup_rfi_flush-after-lpm-migration.patch
queue-4.4/powerpc-pseries-query-hypervisor-for-count-cache-flush-settings.patch
queue-4.4/powerpc-powernv-set-or-clear-security-feature-flags.patch
queue-4.4/powerpc-64s-add-support-for-software-count-cache-flush.patch
queue-4.4/powerpc64s-show-ori31-availability-in-spectre_v1-sysfs-file-not-v2.patch
queue-4.4/powerpc-fsl-flush-the-branch-predictor-at-each-kernel-entry-64bit.patch
queue-4.4/powerpc-fsl-update-spectre-v2-reporting.patch
queue-4.4/powerpc-64s-wire-up-cpu_show_spectre_v2.patch
queue-4.4/powerpc-64-make-meltdown-reporting-book3s-64-specific.patch
queue-4.4/powerpc-rfi-flush-make-it-possible-to-call-setup_rfi_flush-again.patch
queue-4.4/powerpc-64s-add-support-for-ori-barrier_nospec-patching.patch
queue-4.4/powerpc-use-barrier_nospec-in-copy_from_user.patch
queue-4.4/powerpc-64s-fix-section-mismatch-warnings-from-setup_rfi_flush.patch
queue-4.4/powerpc-avoid-code-patching-freed-init-sections.patch
queue-4.4/powerpc-fsl-add-macro-to-flush-the-branch-predictor.patch
queue-4.4/powerpc-xmon-add-rfi-flush-related-fields-to-paca-dump.patch
queue-4.4/powerpc-fsl-add-barrier_nospec-implementation-for-nxp-powerpc-book3e.patch
queue-4.4/powerpc-security-fix-spectre_v2-reporting.patch
queue-4.4/powerpc-add-security-feature-flags-for-spectre-meltdown.patch
queue-4.4/powerpc-powernv-use-the-security-flags-in-pnv_setup_rfi_flush.patch
queue-4.4/powerpc-64-disable-the-speculation-barrier-from-the-command-line.patch
queue-4.4/powerpc-fsl-fix-the-flush-of-branch-predictor.patch
queue-4.4/powerpc-pseries-use-the-security-flags-in-pseries_setup_rfi_flush.patch
queue-4.4/powerpc-64-add-config_ppc_barrier_nospec.patch
queue-4.4/powerpc-64s-move-cpu_show_meltdown.patch
queue-4.4/powerpc-64-use-barrier_nospec-in-syscall-entry.patch
queue-4.4/powerpc-fsl-add-nospectre_v2-command-line-argument.patch
queue-4.4/powerpc-64s-add-new-security-feature-flags-for-count-cache-flush.patch
queue-4.4/powerpc-fsl-add-infrastructure-to-fixup-branch-predictor-flush.patch
queue-4.4/powerpc-rfi-flush-differentiate-enabled-and-patched-flush-types.patch
queue-4.4/powerpc-64s-enhance-the-information-in-cpu_show_spectre_v1.patch
queue-4.4/powerpc-64-call-setup_barrier_nospec-from-setup_arch.patch
queue-4.4/powerpc-rfi-flush-always-enable-fallback-flush-on-pseries.patch
queue-4.4/powerpc-64s-improve-rfi-l1-d-cache-flush-fallback.patch
queue-4.4/powerpc-asm-add-a-patch_site-macro-helpers-for-patching-instructions.patch
queue-4.4/powerpc-pseries-add-new-h_get_cpu_characteristics-flags.patch
queue-4.4/powerpc-64s-enable-barrier_nospec-based-on-firmware-settings.patch
queue-4.4/powerpc-powernv-support-firmware-disable-of-rfi-flush.patch
queue-4.4/powerpc-rfi-flush-move-the-logic-to-avoid-a-redo-into-the-debugfs-code.patch
queue-4.4/powerpc-powernv-query-firmware-for-count-cache-flush-settings.patch
queue-4.4/powerpc-64s-wire-up-cpu_show_spectre_v1.patch
queue-4.4/powerpc-64s-add-barrier_nospec.patch
queue-4.4/powerpc-64s-enhance-the-information-in-cpu_show_meltdown.patch
queue-4.4/powerpc-move-default-security-feature-flags.patch
queue-4.4/powerpc-pseries-fix-clearing-of-security-feature-flags.patch
queue-4.4/powerpc-pseries-restore-default-security-feature-flags-on-setup.patch