[PATCH v2 31/70] x86: CFI hardening for request_irq()

[Andrew Cooper <andrew.cooper3@xxxxxxxxxx>]

... and friends; alloc_direct_apic_vector() and set_direct_apic_vector().

Control Flow Integrity schemes use toolchain and optionally hardware support
to help protect against call/jump/return oriented programming attacks.

Use cf_check to annotate function pointer targets for the toolchain.

Signed-off-by: Andrew Cooper <andrew.cooper3@xxxxxxxxxx>
Acked-by: Jan Beulich <jbeulich@xxxxxxxx>
---
 xen/arch/x86/apic.c                      |  8 ++++----
 xen/arch/x86/cpu/mcheck/mce_intel.c      |  4 ++--
 xen/arch/x86/guest/xen/xen.c             |  2 +-
 xen/arch/x86/hpet.c                      |  4 ++--
 xen/arch/x86/hvm/vmx/vmx.c               |  4 ++--
 xen/arch/x86/include/asm/irq.h           | 16 ++++++++--------
 xen/arch/x86/irq.c                       |  2 +-
 xen/arch/x86/smp.c                       |  6 +++---
 xen/arch/x86/time.c                      |  3 ++-
 xen/drivers/passthrough/amd/iommu_init.c |  4 ++--
 xen/drivers/passthrough/vtd/iommu.c      |  4 ++--
 11 files changed, 29 insertions(+), 28 deletions(-)

diff --git a/xen/arch/x86/apic.c b/xen/arch/x86/apic.c
index 68e4d870c749..5a7a58dc9830 100644
--- a/xen/arch/x86/apic.c
+++ b/xen/arch/x86/apic.c
@@ -1361,7 +1361,7 @@ int reprogram_timer(s_time_t timeout)
     return apic_tmict || !timeout;
 }
 
-void apic_timer_interrupt(struct cpu_user_regs * regs)
+void cf_check apic_timer_interrupt(struct cpu_user_regs *regs)
 {
     ack_APIC_irq();
     perfc_incr(apic_timer);
@@ -1380,7 +1380,7 @@ void smp_send_state_dump(unsigned int cpu)
 /*
  * Spurious interrupts should _never_ happen with our APIC/SMP architecture.
  */
-void spurious_interrupt(struct cpu_user_regs *regs)
+void cf_check spurious_interrupt(struct cpu_user_regs *regs)
 {
     /*
      * Check if this is a vectored interrupt (most likely, as this is probably
@@ -1411,7 +1411,7 @@ void spurious_interrupt(struct cpu_user_regs *regs)
  * This interrupt should never happen with our APIC/SMP architecture
  */
 
-void error_interrupt(struct cpu_user_regs *regs)
+void cf_check error_interrupt(struct cpu_user_regs *regs)
 {
     static const char *const esr_fields[] = {
         "Send CS error",
@@ -1444,7 +1444,7 @@ void error_interrupt(struct cpu_user_regs *regs)
  * This interrupt handles performance counters interrupt
  */
 
-void pmu_apic_interrupt(struct cpu_user_regs *regs)
+void cf_check pmu_apic_interrupt(struct cpu_user_regs *regs)
 {
     ack_APIC_irq();
     vpmu_do_interrupt(regs);
diff --git a/xen/arch/x86/cpu/mcheck/mce_intel.c 
b/xen/arch/x86/cpu/mcheck/mce_intel.c
index a691e10bdcd6..7aaa56fd02eb 100644
--- a/xen/arch/x86/cpu/mcheck/mce_intel.c
+++ b/xen/arch/x86/cpu/mcheck/mce_intel.c
@@ -55,7 +55,7 @@ bool __read_mostly lmce_support;
 #define MCE_RING                0x1
 static DEFINE_PER_CPU(int, last_state);
 
-static void intel_thermal_interrupt(struct cpu_user_regs *regs)
+static void cf_check intel_thermal_interrupt(struct cpu_user_regs *regs)
 {
     uint64_t msr_content;
     unsigned int cpu = smp_processor_id();
@@ -639,7 +639,7 @@ static void cpu_mcheck_disable(void)
         clear_cmci();
 }
 
-static void cmci_interrupt(struct cpu_user_regs *regs)
+static void cf_check cmci_interrupt(struct cpu_user_regs *regs)
 {
     mctelem_cookie_t mctc;
     struct mca_summary bs;
diff --git a/xen/arch/x86/guest/xen/xen.c b/xen/arch/x86/guest/xen/xen.c
index b2aa3a009b4a..17807cdea688 100644
--- a/xen/arch/x86/guest/xen/xen.c
+++ b/xen/arch/x86/guest/xen/xen.c
@@ -170,7 +170,7 @@ static void __init init_memmap(void)
     }
 }
 
-static void xen_evtchn_upcall(struct cpu_user_regs *regs)
+static void cf_check xen_evtchn_upcall(struct cpu_user_regs *regs)
 {
     struct vcpu_info *vcpu_info = this_cpu(vcpu_info);
     unsigned long pending;
diff --git a/xen/arch/x86/hpet.c b/xen/arch/x86/hpet.c
index 7b009a930498..c31fd97579dc 100644
--- a/xen/arch/x86/hpet.c
+++ b/xen/arch/x86/hpet.c
@@ -240,8 +240,8 @@ static void handle_hpet_broadcast(struct hpet_event_channel 
*ch)
     }
 }
 
-static void hpet_interrupt_handler(int irq, void *data,
-        struct cpu_user_regs *regs)
+static void cf_check hpet_interrupt_handler(
+    int irq, void *data, struct cpu_user_regs *regs)
 {
     struct hpet_event_channel *ch = data;
 
diff --git a/xen/arch/x86/hvm/vmx/vmx.c b/xen/arch/x86/hvm/vmx/vmx.c
index 36c8a12cfe7d..dade08f60279 100644
--- a/xen/arch/x86/hvm/vmx/vmx.c
+++ b/xen/arch/x86/hvm/vmx/vmx.c
@@ -2533,7 +2533,7 @@ static struct hvm_function_table __initdata 
vmx_function_table = {
 };
 
 /* Handle VT-d posted-interrupt when VCPU is blocked. */
-static void pi_wakeup_interrupt(struct cpu_user_regs *regs)
+static void cf_check pi_wakeup_interrupt(struct cpu_user_regs *regs)
 {
     struct vmx_vcpu *vmx, *tmp;
     spinlock_t *lock = &per_cpu(vmx_pi_blocking, smp_processor_id()).lock;
@@ -2565,7 +2565,7 @@ static void pi_wakeup_interrupt(struct cpu_user_regs 
*regs)
 }
 
 /* Handle VT-d posted-interrupt when VCPU is running. */
-static void pi_notification_interrupt(struct cpu_user_regs *regs)
+static void cf_check pi_notification_interrupt(struct cpu_user_regs *regs)
 {
     ack_APIC_irq();
     this_cpu(irq_count)++;
diff --git a/xen/arch/x86/include/asm/irq.h b/xen/arch/x86/include/asm/irq.h
index 7c825e9d9c0a..b3f49abc5556 100644
--- a/xen/arch/x86/include/asm/irq.h
+++ b/xen/arch/x86/include/asm/irq.h
@@ -93,14 +93,14 @@ static inline struct cpu_user_regs *set_irq_regs(struct 
cpu_user_regs *new_regs)
 
 #define platform_legacy_irq(irq)       ((irq) < 16)
 
-void event_check_interrupt(struct cpu_user_regs *regs);
-void invalidate_interrupt(struct cpu_user_regs *regs);
-void call_function_interrupt(struct cpu_user_regs *regs);
-void apic_timer_interrupt(struct cpu_user_regs *regs);
-void error_interrupt(struct cpu_user_regs *regs);
-void pmu_apic_interrupt(struct cpu_user_regs *regs);
-void spurious_interrupt(struct cpu_user_regs *regs);
-void irq_move_cleanup_interrupt(struct cpu_user_regs *regs);
+void cf_check event_check_interrupt(struct cpu_user_regs *regs);
+void cf_check invalidate_interrupt(struct cpu_user_regs *regs);
+void cf_check call_function_interrupt(struct cpu_user_regs *regs);
+void cf_check apic_timer_interrupt(struct cpu_user_regs *regs);
+void cf_check error_interrupt(struct cpu_user_regs *regs);
+void cf_check pmu_apic_interrupt(struct cpu_user_regs *regs);
+void cf_check spurious_interrupt(struct cpu_user_regs *regs);
+void cf_check irq_move_cleanup_interrupt(struct cpu_user_regs *regs);
 
 uint8_t alloc_hipriority_vector(void);
 
diff --git a/xen/arch/x86/irq.c b/xen/arch/x86/irq.c
index f43b926ed26b..61e09a356f97 100644
--- a/xen/arch/x86/irq.c
+++ b/xen/arch/x86/irq.c
@@ -744,7 +744,7 @@ void move_native_irq(struct irq_desc *desc)
     desc->handler->enable(desc);
 }
 
-void irq_move_cleanup_interrupt(struct cpu_user_regs *regs)
+void cf_check irq_move_cleanup_interrupt(struct cpu_user_regs *regs)
 {
     unsigned vector, me;
 
diff --git a/xen/arch/x86/smp.c b/xen/arch/x86/smp.c
index b9a696f61963..33748e629a21 100644
--- a/xen/arch/x86/smp.c
+++ b/xen/arch/x86/smp.c
@@ -246,7 +246,7 @@ static cpumask_t flush_cpumask;
 static const void *flush_va;
 static unsigned int flush_flags;
 
-void invalidate_interrupt(struct cpu_user_regs *regs)
+void cf_check invalidate_interrupt(struct cpu_user_regs *regs)
 {
     unsigned int flags = flush_flags;
     ack_APIC_irq();
@@ -385,14 +385,14 @@ void smp_send_nmi_allbutself(void)
     send_IPI_mask(&cpu_online_map, APIC_DM_NMI);
 }
 
-void event_check_interrupt(struct cpu_user_regs *regs)
+void cf_check event_check_interrupt(struct cpu_user_regs *regs)
 {
     ack_APIC_irq();
     perfc_incr(ipis);
     this_cpu(irq_count)++;
 }
 
-void call_function_interrupt(struct cpu_user_regs *regs)
+void cf_check call_function_interrupt(struct cpu_user_regs *regs)
 {
     ack_APIC_irq();
     perfc_incr(ipis);
diff --git a/xen/arch/x86/time.c b/xen/arch/x86/time.c
index 3d767d70f61f..b6e690b76fab 100644
--- a/xen/arch/x86/time.c
+++ b/xen/arch/x86/time.c
@@ -196,7 +196,8 @@ static void smp_send_timer_broadcast_ipi(void)
     }
 }
 
-static void timer_interrupt(int irq, void *dev_id, struct cpu_user_regs *regs)
+static void cf_check timer_interrupt(
+    int irq, void *dev_id, struct cpu_user_regs *regs)
 {
     ASSERT(local_irq_is_enabled());
 
diff --git a/xen/drivers/passthrough/amd/iommu_init.c 
b/xen/drivers/passthrough/amd/iommu_init.c
index cebcd68a6c04..d2ad282e93d3 100644
--- a/xen/drivers/passthrough/amd/iommu_init.c
+++ b/xen/drivers/passthrough/amd/iommu_init.c
@@ -715,8 +715,8 @@ static void cf_check do_amd_iommu_irq(void *unused)
     }
 }
 
-static void iommu_interrupt_handler(int irq, void *dev_id,
-                                    struct cpu_user_regs *regs)
+static void cf_check iommu_interrupt_handler(
+    int irq, void *dev_id, struct cpu_user_regs *regs)
 {
     unsigned long flags;
     struct amd_iommu *iommu = dev_id;
diff --git a/xen/drivers/passthrough/vtd/iommu.c 
b/xen/drivers/passthrough/vtd/iommu.c
index 4d7703dd9a20..fc3ff064b692 100644
--- a/xen/drivers/passthrough/vtd/iommu.c
+++ b/xen/drivers/passthrough/vtd/iommu.c
@@ -1117,8 +1117,8 @@ static void cf_check do_iommu_page_fault(void *unused)
         __do_iommu_page_fault(drhd->iommu);
 }
 
-static void iommu_page_fault(int irq, void *dev_id,
-                             struct cpu_user_regs *regs)
+static void cf_check iommu_page_fault(
+    int irq, void *dev_id, struct cpu_user_regs *regs)
 {
     /*
      * Just flag the tasklet as runnable. This is fine, according to VT-d
-- 
2.11.0