c/pve-kernel-lowlatency-qoup
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

backport Zenbleed stop-gap fix CVE-2023-20593

Browse Source 
the actual fix is the microcode update, but this is a stop-gap (with
a performance penalty) setting a chicken bit on affected CPUs that do
not have the new enough microcode loaded, disabling some features.

Signed-off-by: Thomas Lamprecht <t.lamprecht@proxmox.com>
This commit is contained in:
Thomas Lamprecht 2023-07-20 12:08:01 +02:00
parent 2914b5a244
commit 237da8e53e
2 changed files with 352 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

182
patches/kernel/0025-x86-cpu-amd-Move-the-errata-checking-functionality-u.patch Normal file
View File

@ -0,0 +1,182 @@
From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: "Borislav Petkov (AMD)" <bp@alien8.de>
Date: Sat, 15 Jul 2023 13:31:32 +0200
Subject: [PATCH] x86/cpu/amd: Move the errata checking functionality up
Upstream commit: 8b6f687743dacce83dbb0c7cfacf88bab00f808a
Avoid new and remove old forward declarations.
No functional changes.
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Thomas Lamprecht <t.lamprecht@proxmox.com>
---
arch/x86/kernel/cpu/amd.c | 139 ++++++++++++++++++--------------------
1 file changed, 67 insertions(+), 72 deletions(-)
diff --git a/arch/x86/kernel/cpu/amd.c b/arch/x86/kernel/cpu/amd.c
index 962d71bb64a8..7caff84f12ca 100644
--- a/arch/x86/kernel/cpu/amd.c
+++ b/arch/x86/kernel/cpu/amd.c
@@ -27,11 +27,6 @@
#include "cpu.h"
-static const int amd_erratum_383[];
-static const int amd_erratum_400[];
-static const int amd_erratum_1054[];
-static bool cpu_has_amd_erratum(struct cpuinfo_x86 *cpu, const int *erratum);
-
/*
* nodes_per_socket: Stores the number of nodes per socket.
* Refer to Fam15h Models 00-0fh BKDG - CPUID Fn8000_001E_ECX
@@ -39,6 +34,73 @@ static bool cpu_has_amd_erratum(struct cpuinfo_x86 *cpu, const int *erratum);
*/
static u32 nodes_per_socket = 1;
+/*
+ * AMD errata checking
+ *
+ * Errata are defined as arrays of ints using the AMD_LEGACY_ERRATUM() or
+ * AMD_OSVW_ERRATUM() macros. The latter is intended for newer errata that
+ * have an OSVW id assigned, which it takes as first argument. Both take a
+ * variable number of family-specific model-stepping ranges created by
+ * AMD_MODEL_RANGE().
+ *
+ * Example:
+ *
+ * const int amd_erratum_319[] =
+ * AMD_LEGACY_ERRATUM(AMD_MODEL_RANGE(0x10, 0x2, 0x1, 0x4, 0x2),
+ * AMD_MODEL_RANGE(0x10, 0x8, 0x0, 0x8, 0x0),
+ * AMD_MODEL_RANGE(0x10, 0x9, 0x0, 0x9, 0x0));
+ */
+
+#define AMD_LEGACY_ERRATUM(...) { -1, __VA_ARGS__, 0 }
+#define AMD_OSVW_ERRATUM(osvw_id, ...) { osvw_id, __VA_ARGS__, 0 }
+#define AMD_MODEL_RANGE(f, m_start, s_start, m_end, s_end) \
+ ((f << 24) | (m_start << 16) | (s_start << 12) | (m_end << 4) | (s_end))
+#define AMD_MODEL_RANGE_FAMILY(range) (((range) >> 24) & 0xff)
+#define AMD_MODEL_RANGE_START(range) (((range) >> 12) & 0xfff)
+#define AMD_MODEL_RANGE_END(range) ((range) & 0xfff)
+
+static const int amd_erratum_400[] =
+ AMD_OSVW_ERRATUM(1, AMD_MODEL_RANGE(0xf, 0x41, 0x2, 0xff, 0xf),
+ AMD_MODEL_RANGE(0x10, 0x2, 0x1, 0xff, 0xf));
+
+static const int amd_erratum_383[] =
+ AMD_OSVW_ERRATUM(3, AMD_MODEL_RANGE(0x10, 0, 0, 0xff, 0xf));
+
+/* #1054: Instructions Retired Performance Counter May Be Inaccurate */
+static const int amd_erratum_1054[] =
+ AMD_LEGACY_ERRATUM(AMD_MODEL_RANGE(0x17, 0, 0, 0x2f, 0xf));
+
+static bool cpu_has_amd_erratum(struct cpuinfo_x86 *cpu, const int *erratum)
+{
+ int osvw_id = *erratum++;
+ u32 range;
+ u32 ms;
+
+ if (osvw_id >= 0 && osvw_id < 65536 &&
+ cpu_has(cpu, X86_FEATURE_OSVW)) {
+ u64 osvw_len;
+
+ rdmsrl(MSR_AMD64_OSVW_ID_LENGTH, osvw_len);
+ if (osvw_id < osvw_len) {
+ u64 osvw_bits;
+
+ rdmsrl(MSR_AMD64_OSVW_STATUS + (osvw_id >> 6),
+ osvw_bits);
+ return osvw_bits & (1ULL << (osvw_id & 0x3f));
+ }
+ }
+
+ /* OSVW unavailable or ID unknown, match family-model-stepping range */
+ ms = (cpu->x86_model << 4) | cpu->x86_stepping;
+ while ((range = *erratum++))
+ if ((cpu->x86 == AMD_MODEL_RANGE_FAMILY(range)) &&
+ (ms >= AMD_MODEL_RANGE_START(range)) &&
+ (ms <= AMD_MODEL_RANGE_END(range)))
+ return true;
+
+ return false;
+}
+
static inline int rdmsrl_amd_safe(unsigned msr, unsigned long long *p)
{
u32 gprs[8] = { 0 };
@@ -1095,73 +1157,6 @@ static const struct cpu_dev amd_cpu_dev = {
cpu_dev_register(amd_cpu_dev);
-/*
- * AMD errata checking
- *
- * Errata are defined as arrays of ints using the AMD_LEGACY_ERRATUM() or
- * AMD_OSVW_ERRATUM() macros. The latter is intended for newer errata that
- * have an OSVW id assigned, which it takes as first argument. Both take a
- * variable number of family-specific model-stepping ranges created by
- * AMD_MODEL_RANGE().
- *
- * Example:
- *
- * const int amd_erratum_319[] =
- * AMD_LEGACY_ERRATUM(AMD_MODEL_RANGE(0x10, 0x2, 0x1, 0x4, 0x2),
- * AMD_MODEL_RANGE(0x10, 0x8, 0x0, 0x8, 0x0),
- * AMD_MODEL_RANGE(0x10, 0x9, 0x0, 0x9, 0x0));
- */
-
-#define AMD_LEGACY_ERRATUM(...) { -1, __VA_ARGS__, 0 }
-#define AMD_OSVW_ERRATUM(osvw_id, ...) { osvw_id, __VA_ARGS__, 0 }
-#define AMD_MODEL_RANGE(f, m_start, s_start, m_end, s_end) \
- ((f << 24) | (m_start << 16) | (s_start << 12) | (m_end << 4) | (s_end))
-#define AMD_MODEL_RANGE_FAMILY(range) (((range) >> 24) & 0xff)
-#define AMD_MODEL_RANGE_START(range) (((range) >> 12) & 0xfff)
-#define AMD_MODEL_RANGE_END(range) ((range) & 0xfff)
-
-static const int amd_erratum_400[] =
- AMD_OSVW_ERRATUM(1, AMD_MODEL_RANGE(0xf, 0x41, 0x2, 0xff, 0xf),
- AMD_MODEL_RANGE(0x10, 0x2, 0x1, 0xff, 0xf));
-
-static const int amd_erratum_383[] =
- AMD_OSVW_ERRATUM(3, AMD_MODEL_RANGE(0x10, 0, 0, 0xff, 0xf));
-
-/* #1054: Instructions Retired Performance Counter May Be Inaccurate */
-static const int amd_erratum_1054[] =
- AMD_LEGACY_ERRATUM(AMD_MODEL_RANGE(0x17, 0, 0, 0x2f, 0xf));
-
-static bool cpu_has_amd_erratum(struct cpuinfo_x86 *cpu, const int *erratum)
-{
- int osvw_id = *erratum++;
- u32 range;
- u32 ms;
-
- if (osvw_id >= 0 && osvw_id < 65536 &&
- cpu_has(cpu, X86_FEATURE_OSVW)) {
- u64 osvw_len;
-
- rdmsrl(MSR_AMD64_OSVW_ID_LENGTH, osvw_len);
- if (osvw_id < osvw_len) {
- u64 osvw_bits;
-
- rdmsrl(MSR_AMD64_OSVW_STATUS + (osvw_id >> 6),
- osvw_bits);
- return osvw_bits & (1ULL << (osvw_id & 0x3f));
- }
- }
-
- /* OSVW unavailable or ID unknown, match family-model-stepping range */
- ms = (cpu->x86_model << 4) | cpu->x86_stepping;
- while ((range = *erratum++))
- if ((cpu->x86 == AMD_MODEL_RANGE_FAMILY(range)) &&
- (ms >= AMD_MODEL_RANGE_START(range)) &&
- (ms <= AMD_MODEL_RANGE_END(range)))
- return true;
-
- return false;
-}
-
void set_dr_addr_mask(unsigned long mask, int dr)
{
if (!boot_cpu_has(X86_FEATURE_BPEXT))

170
patches/kernel/0026-x86-cpu-amd-Add-a-Zenbleed-fix.patch Normal file
View File

@ -0,0 +1,170 @@
From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: "Borislav Petkov (AMD)" <bp@alien8.de>
Date: Sat, 15 Jul 2023 13:41:28 +0200
Subject: [PATCH] x86/cpu/amd: Add a Zenbleed fix
Upstream commit: 522b1d69219d8f083173819fde04f994aa051a98
Add a fix for the Zen2 VZEROUPPER data corruption bug where under
certain circumstances executing VZEROUPPER can cause register
corruption or leak data.
The optimal fix is through microcode but in the case the proper
microcode revision has not been applied, enable a fallback fix using
a chicken bit.
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Thomas Lamprecht <t.lamprecht@proxmox.com>
---
arch/x86/include/asm/microcode.h | 1 +
arch/x86/include/asm/microcode_amd.h | 2 +
arch/x86/include/asm/msr-index.h | 1 +
arch/x86/kernel/cpu/amd.c | 60 ++++++++++++++++++++++++++++
arch/x86/kernel/cpu/common.c | 2 +
5 files changed, 66 insertions(+)
diff --git a/arch/x86/include/asm/microcode.h b/arch/x86/include/asm/microcode.h
index 1bf064a14b95..4ca377efc986 100644
--- a/arch/x86/include/asm/microcode.h
+++ b/arch/x86/include/asm/microcode.h
@@ -5,6 +5,7 @@
#include <asm/cpu.h>
#include <linux/earlycpio.h>
#include <linux/initrd.h>
+#include <asm/microcode_amd.h>
struct ucode_patch {
struct list_head plist;
diff --git a/arch/x86/include/asm/microcode_amd.h b/arch/x86/include/asm/microcode_amd.h
index a645b25ee442..403a8e76b310 100644
--- a/arch/x86/include/asm/microcode_amd.h
+++ b/arch/x86/include/asm/microcode_amd.h
@@ -48,11 +48,13 @@ extern void __init load_ucode_amd_bsp(unsigned int family);
extern void load_ucode_amd_ap(unsigned int family);
extern int __init save_microcode_in_initrd_amd(unsigned int family);
void reload_ucode_amd(unsigned int cpu);
+extern void amd_check_microcode(void);
#else
static inline void __init load_ucode_amd_bsp(unsigned int family) {}
static inline void load_ucode_amd_ap(unsigned int family) {}
static inline int __init
save_microcode_in_initrd_amd(unsigned int family) { return -EINVAL; }
static inline void reload_ucode_amd(unsigned int cpu) {}
+static inline void amd_check_microcode(void) {}
#endif
#endif /* _ASM_X86_MICROCODE_AMD_H */
diff --git a/arch/x86/include/asm/msr-index.h b/arch/x86/include/asm/msr-index.h
index ef52c3d48640..af1320071e18 100644
--- a/arch/x86/include/asm/msr-index.h
+++ b/arch/x86/include/asm/msr-index.h
@@ -503,6 +503,7 @@
#define MSR_AMD64_DE_CFG 0xc0011029
#define MSR_AMD64_DE_CFG_LFENCE_SERIALIZE_BIT 1
#define MSR_AMD64_DE_CFG_LFENCE_SERIALIZE BIT_ULL(MSR_AMD64_DE_CFG_LFENCE_SERIALIZE_BIT)
+#define MSR_AMD64_DE_CFG_ZEN2_FP_BACKUP_FIX_BIT 9
#define MSR_AMD64_BU_CFG2 0xc001102a
#define MSR_AMD64_IBSFETCHCTL 0xc0011030
diff --git a/arch/x86/kernel/cpu/amd.c b/arch/x86/kernel/cpu/amd.c
index 7caff84f12ca..a2f7311df71e 100644
--- a/arch/x86/kernel/cpu/amd.c
+++ b/arch/x86/kernel/cpu/amd.c
@@ -70,6 +70,11 @@ static const int amd_erratum_383[] =
static const int amd_erratum_1054[] =
AMD_LEGACY_ERRATUM(AMD_MODEL_RANGE(0x17, 0, 0, 0x2f, 0xf));
+static const int amd_zenbleed[] =
+ AMD_LEGACY_ERRATUM(AMD_MODEL_RANGE(0x17, 0x30, 0x0, 0x4f, 0xf),
+ AMD_MODEL_RANGE(0x17, 0x60, 0x0, 0x7f, 0xf),
+ AMD_MODEL_RANGE(0x17, 0xa0, 0x0, 0xaf, 0xf));
+
static bool cpu_has_amd_erratum(struct cpuinfo_x86 *cpu, const int *erratum)
{
int osvw_id = *erratum++;
@@ -973,6 +978,47 @@ static void init_amd_zn(struct cpuinfo_x86 *c)
}
}
+static bool cpu_has_zenbleed_microcode(void)
+{
+ u32 good_rev = 0;
+
+ switch (boot_cpu_data.x86_model) {
+ case 0x30 ... 0x3f: good_rev = 0x0830107a; break;
+ case 0x60 ... 0x67: good_rev = 0x0860010b; break;
+ case 0x68 ... 0x6f: good_rev = 0x08608105; break;
+ case 0x70 ... 0x7f: good_rev = 0x08701032; break;
+ case 0xa0 ... 0xaf: good_rev = 0x08a00008; break;
+
+ default:
+ return false;
+ break;
+ }
+
+ if (boot_cpu_data.microcode < good_rev)
+ return false;
+
+ return true;
+}
+
+static void zenbleed_check(struct cpuinfo_x86 *c)
+{
+ if (!cpu_has_amd_erratum(c, amd_zenbleed))
+ return;
+
+ if (cpu_has(c, X86_FEATURE_HYPERVISOR))
+ return;
+
+ if (!cpu_has(c, X86_FEATURE_AVX))
+ return;
+
+ if (!cpu_has_zenbleed_microcode()) {
+ pr_notice_once("Zenbleed: please update your microcode for the most optimal fix\n");
+ msr_set_bit(MSR_AMD64_DE_CFG, MSR_AMD64_DE_CFG_ZEN2_FP_BACKUP_FIX_BIT);
+ } else {
+ msr_clear_bit(MSR_AMD64_DE_CFG, MSR_AMD64_DE_CFG_ZEN2_FP_BACKUP_FIX_BIT);
+ }
+}
+
static void init_amd(struct cpuinfo_x86 *c)
{
early_init_amd(c);
@@ -1062,6 +1108,8 @@ static void init_amd(struct cpuinfo_x86 *c)
msr_set_bit(MSR_K7_HWCR, MSR_K7_HWCR_IRPERF_EN_BIT);
check_null_seg_clears_base(c);
+
+ zenbleed_check(c);
}
#ifdef CONFIG_X86_32
@@ -1191,3 +1239,15 @@ u32 amd_get_highest_perf(void)
return 255;
}
EXPORT_SYMBOL_GPL(amd_get_highest_perf);
+
+static void zenbleed_check_cpu(void *unused)
+{
+ struct cpuinfo_x86 *c = &cpu_data(smp_processor_id());
+
+ zenbleed_check(c);
+}
+
+void amd_check_microcode(void)
+{
+ on_each_cpu(zenbleed_check_cpu, NULL, 1);
+}
diff --git a/arch/x86/kernel/cpu/common.c b/arch/x86/kernel/cpu/common.c
index 40f48b8cafc7..82e3756260ea 100644
--- a/arch/x86/kernel/cpu/common.c
+++ b/arch/x86/kernel/cpu/common.c
@@ -2260,6 +2260,8 @@ void microcode_check(struct cpuinfo_x86 *prev_info)
perf_check_microcode();
+ amd_check_microcode();
+
store_cpu_caps(&curr_info);
if (!memcmp(&prev_info->x86_capability, &curr_info.x86_capability,