[PATCH v2 41/70] x86/quirks: CFI hardening

[Andrew Cooper <andrew.cooper3@citrix.com>]

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@citrix.com>
Acked-by: Jan Beulich <jbeulich@suse.com>
---
 xen/arch/x86/dmi_scan.c               | 10 +++++-----
 xen/arch/x86/hvm/quirks.c             |  2 +-
 xen/arch/x86/shutdown.c               |  2 +-
 xen/arch/x86/x86_64/mmconfig-shared.c |  8 ++++----
 4 files changed, 11 insertions(+), 11 deletions(-)

diff --git a/xen/arch/x86/dmi_scan.c b/xen/arch/x86/dmi_scan.c
index d27cd3450a29..81f80c053a7a 100644
--- a/xen/arch/x86/dmi_scan.c
+++ b/xen/arch/x86/dmi_scan.c
@@ -476,7 +476,7 @@ static void __init dmi_save_ident(const struct dmi_header *dm, int slot, int str
 #define NO_MATCH	{ DMI_NONE, NULL}
 #define MATCH		DMI_MATCH
 
-static int __init ich10_bios_quirk(const struct dmi_system_id *d)
+static int __init cf_check ich10_bios_quirk(const struct dmi_system_id *d)
 {
     u32 port, smictl;
 
@@ -499,14 +499,14 @@ static int __init ich10_bios_quirk(const struct dmi_system_id *d)
     return 0;
 }
 
-static __init int reset_videomode_after_s3(const struct dmi_blacklist *d)
+static __init int cf_check reset_videomode_after_s3(const struct dmi_blacklist *d)
 {
 	/* See wakeup.S */
 	acpi_video_flags |= 2;
 	return 0;
 }
 
-static __init int dmi_disable_acpi(const struct dmi_blacklist *d)
+static __init int cf_check dmi_disable_acpi(const struct dmi_blacklist *d)
 { 
 	if (!acpi_force) { 
 		printk(KERN_NOTICE "%s detected: acpi off\n",d->ident);
@@ -521,7 +521,7 @@ static __init int dmi_disable_acpi(const struct dmi_blacklist *d)
 /*
  * Limit ACPI to CPU enumeration for HT
  */
-static __init int force_acpi_ht(const struct dmi_blacklist *d)
+static __init int cf_check force_acpi_ht(const struct dmi_blacklist *d)
 { 
 	if (!acpi_force) { 
 		printk(KERN_NOTICE "%s detected: force use of acpi=ht\n", d->ident);
@@ -650,7 +650,7 @@ static const struct dmi_blacklist __initconstrel dmi_blacklist[] = {
  *	out of here.
  */
 
-static void __init dmi_decode(const struct dmi_header *dm)
+static void __init cf_check dmi_decode(const struct dmi_header *dm)
 {
 #ifdef DMI_DEBUG
 	const uint8_t *data = (const void *)dm;
diff --git a/xen/arch/x86/hvm/quirks.c b/xen/arch/x86/hvm/quirks.c
index 917356b1312c..2adab1f4b84b 100644
--- a/xen/arch/x86/hvm/quirks.c
+++ b/xen/arch/x86/hvm/quirks.c
@@ -25,7 +25,7 @@
 s8 __read_mostly hvm_port80_allowed = -1;
 boolean_param("hvm_port80", hvm_port80_allowed);
 
-static int __init dmi_hvm_deny_port80(const struct dmi_system_id *id)
+static int __init cf_check dmi_hvm_deny_port80(const struct dmi_system_id *id)
 {
     printk(XENLOG_WARNING "%s: port 0x80 access %s allowed for HVM guests\n",
            id->ident, hvm_port80_allowed > 0 ? "forcibly" : "not");
diff --git a/xen/arch/x86/shutdown.c b/xen/arch/x86/shutdown.c
index 30985d36a612..7619544d14da 100644
--- a/xen/arch/x86/shutdown.c
+++ b/xen/arch/x86/shutdown.c
@@ -158,7 +158,7 @@ static void default_reboot_type(void)
         reboot_type = BOOT_ACPI;
 }
 
-static int __init override_reboot(const struct dmi_system_id *d)
+static int __init cf_check override_reboot(const struct dmi_system_id *d)
 {
     enum reboot_type type = (long)d->driver_data;
 
diff --git a/xen/arch/x86/x86_64/mmconfig-shared.c b/xen/arch/x86/x86_64/mmconfig-shared.c
index 2fa7f3f0bc4b..74b22b71a19c 100644
--- a/xen/arch/x86/x86_64/mmconfig-shared.c
+++ b/xen/arch/x86/x86_64/mmconfig-shared.c
@@ -62,7 +62,7 @@ static int __init cf_check parse_mmcfg(const char *s)
 }
 custom_param("mmcfg", parse_mmcfg);
 
-static const char __init *pci_mmcfg_e7520(void)
+static const char *__init cf_check pci_mmcfg_e7520(void)
 {
     u32 win;
     win = pci_conf_read16(PCI_SBDF(0, 0, 0, 0), 0xce);
@@ -84,7 +84,7 @@ static const char __init *pci_mmcfg_e7520(void)
     return "Intel Corporation E7520 Memory Controller Hub";
 }
 
-static const char __init *pci_mmcfg_intel_945(void)
+static const char *__init cf_check pci_mmcfg_intel_945(void)
 {
     u32 pciexbar, mask = 0, len = 0;
 
@@ -137,7 +137,7 @@ static const char __init *pci_mmcfg_intel_945(void)
     return "Intel Corporation 945G/GZ/P/PL Express Memory Controller Hub";
 }
 
-static const char __init *pci_mmcfg_amd_fam10h(void)
+static const char *__init cf_check pci_mmcfg_amd_fam10h(void)
 {
     uint32_t address;
     uint64_t base, msr_content;
@@ -190,7 +190,7 @@ static const char __init *pci_mmcfg_amd_fam10h(void)
     return "AMD Family 10h NB";
 }
 
-static const char __init *pci_mmcfg_nvidia_mcp55(void)
+static const char *__init cf_check pci_mmcfg_nvidia_mcp55(void)
 {
     static bool_t __initdata mcp55_checked;
     int bus, i;
-- 
2.11.0