From: "Borislav Petkov (AMD)" bp@alien8.de
stable inclusion from stable-v5.10.187 commit 93df00f9d48d48466ddbe01a06eaaf3311ecfb53 category: bugfix bugzilla: https://gitee.com/src-openeuler/kernel/issues/I7NLYY CVE: CVE-2023-20593
Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=...
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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
Conflicts: arch/x86/include/asm/microcode_amd.h arch/x86/kernel/cpu/common.c
Signed-off-by: Yu Liao liaoyu15@huawei.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 | 1 + 5 files changed, 65 insertions(+)
diff --git a/arch/x86/include/asm/microcode.h b/arch/x86/include/asm/microcode.h index 91a06cef50c1..3e398751b73c 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 7063b5a43220..b56a1c0d5f60 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(void); +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(void) {} +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 fd3653d8699a..272c02b80944 100644 --- a/arch/x86/include/asm/msr-index.h +++ b/arch/x86/include/asm/msr-index.h @@ -494,6 +494,7 @@ #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 284fe7a0e745..f5d1fac60486 100644 --- a/arch/x86/kernel/cpu/amd.c +++ b/arch/x86/kernel/cpu/amd.c @@ -71,6 +71,11 @@ 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++; @@ -1021,6 +1026,47 @@ 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); @@ -1111,6 +1157,8 @@ 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 @@ -1224,3 +1272,15 @@ void set_dr_addr_mask(unsigned long mask, int dr) break; } } + +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 4192886ab276..c9f2eb1b32b6 100644 --- a/arch/x86/kernel/cpu/common.c +++ b/arch/x86/kernel/cpu/common.c @@ -2143,6 +2143,7 @@ void microcode_check(void)
perf_check_microcode();
+ amd_check_microcode(); /* Reload CPUID max function as it might've changed. */ info.cpuid_level = cpuid_eax(0);