[kernel-hardening] [PATCH 1/4] irq: set {msi_domain,syscore}_ops as __ro_after_init

[Jess Frazelle <me@jessfraz.com>]

Marked msi_domain_ops structs as __ro_after_init when called only during init.
Marked syscore_ops structs as __ro_after_init when register_syscore_ops was
called only during init. Most of the caller functions were already annotated as
__init.
This protects the data structure from accidental corruption.

Suggested-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Jess Frazelle <me@jessfraz.com>
---
 drivers/staging/fsl-mc/bus/irq-gic-v3-its-fsl-mc-msi.c | 2 +-
 kernel/irq/generic-chip.c                              | 2 +-
 kernel/irq/msi.c                                       | 2 +-
 kernel/irq/pm.c                                        | 2 +-
 4 files changed, 4 insertions(+), 4 deletions(-)

diff --git a/drivers/staging/fsl-mc/bus/irq-gic-v3-its-fsl-mc-msi.c b/drivers/staging/fsl-mc/bus/irq-gic-v3-its-fsl-mc-msi.c
index 6b1cd574644f..0e2c1b5e13b7 100644
--- a/drivers/staging/fsl-mc/bus/irq-gic-v3-its-fsl-mc-msi.c
+++ b/drivers/staging/fsl-mc/bus/irq-gic-v3-its-fsl-mc-msi.c
@@ -51,7 +51,7 @@ static int its_fsl_mc_msi_prepare(struct irq_domain *msi_domain,
 	return msi_info->ops->msi_prepare(msi_domain->parent, dev, nvec, info);
 }

-static struct msi_domain_ops its_fsl_mc_msi_ops = {
+static struct msi_domain_ops its_fsl_mc_msi_ops __ro_after_init = {
 	.msi_prepare = its_fsl_mc_msi_prepare,
 };

diff --git a/kernel/irq/generic-chip.c b/kernel/irq/generic-chip.c
index ee32870079c9..cca63dbaabea 100644
--- a/kernel/irq/generic-chip.c
+++ b/kernel/irq/generic-chip.c
@@ -623,7 +623,7 @@ static void irq_gc_shutdown(void)
 	}
 }

-static struct syscore_ops irq_gc_syscore_ops = {
+static struct syscore_ops irq_gc_syscore_ops __ro_after_init = {
 	.suspend = irq_gc_suspend,
 	.resume = irq_gc_resume,
 	.shutdown = irq_gc_shutdown,
diff --git a/kernel/irq/msi.c b/kernel/irq/msi.c
index ee230063f033..0e5b723f710f 100644
--- a/kernel/irq/msi.c
+++ b/kernel/irq/msi.c
@@ -217,7 +217,7 @@ static int msi_domain_ops_check(struct irq_domain *domain,
 	return 0;
 }

-static struct msi_domain_ops msi_domain_ops_default = {
+static struct msi_domain_ops msi_domain_ops_default __ro_after_init = {
 	.get_hwirq	= msi_domain_ops_get_hwirq,
 	.msi_init	= msi_domain_ops_init,
 	.msi_check	= msi_domain_ops_check,
diff --git a/kernel/irq/pm.c b/kernel/irq/pm.c
index cea1de0161f1..d6b889bed323 100644
--- a/kernel/irq/pm.c
+++ b/kernel/irq/pm.c
@@ -185,7 +185,7 @@ static void irq_pm_syscore_resume(void)
 	resume_irqs(true);
 }

-static struct syscore_ops irq_pm_syscore_ops = {
+static struct syscore_ops irq_pm_syscore_ops __ro_after_init = {
 	.resume		= irq_pm_syscore_resume,
 };

--
2.11.0