diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt index 443807ae55d0d..eb998bf963192 100644 --- a/Documentation/admin-guide/kernel-parameters.txt +++ b/Documentation/admin-guide/kernel-parameters.txt @@ -1741,6 +1741,12 @@ 0 -- machine default 1 -- force brightness inversion + ia32_emulation= [X86-64] + Format: + When true, allows loading 32-bit programs and executing 32-bit + syscalls, essentially overriding IA32_EMULATION_DEFAULT_DISABLED at + boot time. When false, unconditionally disables IA32 emulation. + icn= [HW,ISDN] Format: [,[,[,]]] diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig index 4af28a7a1ce41..af7d48f3506a0 100644 --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig @@ -2944,6 +2944,15 @@ config IA32_EMULATION 64-bit kernel. You should likely turn this on, unless you're 100% sure that you don't have any 32-bit programs left. +config IA32_EMULATION_DEFAULT_DISABLED + bool "IA32 emulation disabled by default" + default n + depends on IA32_EMULATION + help + Make IA32 emulation disabled by default. This prevents loading 32-bit + processes and access to 32-bit syscalls. If unsure, leave it to its + default value. + config IA32_AOUT tristate "IA32 a.out support" depends on IA32_EMULATION diff --git a/arch/x86/boot/compressed/sev.c b/arch/x86/boot/compressed/sev.c index 97f7271c3dc2c..30a344a66759a 100644 --- a/arch/x86/boot/compressed/sev.c +++ b/arch/x86/boot/compressed/sev.c @@ -227,6 +227,10 @@ void do_boot_stage2_vc(struct pt_regs *regs, unsigned long exit_code) if (result != ES_OK) goto finish; + result = vc_check_opcode_bytes(&ctxt, exit_code); + if (result != ES_OK) + goto finish; + switch (exit_code) { case SVM_EXIT_RDTSC: case SVM_EXIT_RDTSCP: diff --git a/arch/x86/coco/tdx/tdx.c b/arch/x86/coco/tdx/tdx.c index cfd4c95b9f045..2743d56906803 100644 --- a/arch/x86/coco/tdx/tdx.c +++ b/arch/x86/coco/tdx/tdx.c @@ -10,6 +10,7 @@ #include #include #include +#include #include #include #include diff --git a/arch/x86/entry/common.c b/arch/x86/entry/common.c index 6c2826417b337..334e29e9d6ed0 100644 --- a/arch/x86/entry/common.c +++ b/arch/x86/entry/common.c @@ -19,12 +19,14 @@ #include #include #include +#include #ifdef CONFIG_XEN_PV #include #include #endif +#include #include #include #include @@ -96,6 +98,16 @@ static __always_inline int syscall_32_enter(struct pt_regs *regs) return (int)regs->orig_ax; } +#ifdef CONFIG_IA32_EMULATION +bool __ia32_enabled __ro_after_init = !IS_ENABLED(CONFIG_IA32_EMULATION_DEFAULT_DISABLED); + +static int __init ia32_emulation_override_cmdline(char *arg) +{ + return kstrtobool(arg, &__ia32_enabled); +} +early_param("ia32_emulation", ia32_emulation_override_cmdline); +#endif + /* * Invoke a 32-bit syscall. Called with IRQs on in CONTEXT_KERNEL. */ @@ -115,7 +127,96 @@ static __always_inline void do_syscall_32_irqs_on(struct pt_regs *regs, int nr) } } -/* Handles int $0x80 */ +#ifdef CONFIG_IA32_EMULATION +static __always_inline bool int80_is_external(void) +{ + const unsigned int offs = (0x80 / 32) * 0x10; + const u32 bit = BIT(0x80 % 32); + + /* The local APIC on XENPV guests is fake */ + if (cpu_feature_enabled(X86_FEATURE_XENPV)) + return false; + + /* + * If vector 0x80 is set in the APIC ISR then this is an external + * interrupt. Either from broken hardware or injected by a VMM. + * + * Note: In guest mode this is only valid for secure guests where + * the secure module fully controls the vAPIC exposed to the guest. + */ + return apic_read(APIC_ISR + offs) & bit; +} + +/** + * int80_emulation - 32-bit legacy syscall entry + * + * This entry point can be used by 32-bit and 64-bit programs to perform + * 32-bit system calls. Instances of INT $0x80 can be found inline in + * various programs and libraries. It is also used by the vDSO's + * __kernel_vsyscall fallback for hardware that doesn't support a faster + * entry method. Restarted 32-bit system calls also fall back to INT + * $0x80 regardless of what instruction was originally used to do the + * system call. + * + * This is considered a slow path. It is not used by most libc + * implementations on modern hardware except during process startup. + * + * The arguments for the INT $0x80 based syscall are on stack in the + * pt_regs structure: + * eax: system call number + * ebx, ecx, edx, esi, edi, ebp: arg1 - arg 6 + */ +DEFINE_IDTENTRY_RAW(int80_emulation) +{ + int nr; + + /* Kernel does not use INT $0x80! */ + if (unlikely(!user_mode(regs))) { + irqentry_enter(regs); + instrumentation_begin(); + panic("Unexpected external interrupt 0x80\n"); + } + + /* + * Establish kernel context for instrumentation, including for + * int80_is_external() below which calls into the APIC driver. + * Identical for soft and external interrupts. + */ + enter_from_user_mode(regs); + + instrumentation_begin(); + add_random_kstack_offset(); + + /* Validate that this is a soft interrupt to the extent possible */ + if (unlikely(int80_is_external())) + panic("Unexpected external interrupt 0x80\n"); + + /* + * The low level idtentry code pushed -1 into regs::orig_ax + * and regs::ax contains the syscall number. + * + * User tracing code (ptrace or signal handlers) might assume + * that the regs::orig_ax contains a 32-bit number on invoking + * a 32-bit syscall. + * + * Establish the syscall convention by saving the 32bit truncated + * syscall number in regs::orig_ax and by invalidating regs::ax. + */ + regs->orig_ax = regs->ax & GENMASK(31, 0); + regs->ax = -ENOSYS; + + nr = syscall_32_enter(regs); + + local_irq_enable(); + nr = syscall_enter_from_user_mode_work(regs, nr); + do_syscall_32_irqs_on(regs, nr); + + instrumentation_end(); + syscall_exit_to_user_mode(regs); +} +#else /* CONFIG_IA32_EMULATION */ + +/* Handles int $0x80 on a 32bit kernel */ __visible noinstr void do_int80_syscall_32(struct pt_regs *regs) { int nr = syscall_32_enter(regs); @@ -134,6 +235,7 @@ __visible noinstr void do_int80_syscall_32(struct pt_regs *regs) instrumentation_end(); syscall_exit_to_user_mode(regs); } +#endif /* !CONFIG_IA32_EMULATION */ static noinstr bool __do_fast_syscall_32(struct pt_regs *regs) { diff --git a/arch/x86/entry/entry_64.S b/arch/x86/entry/entry_64.S index f314ae35f0269..e4ecbc5fdf701 100644 --- a/arch/x86/entry/entry_64.S +++ b/arch/x86/entry/entry_64.S @@ -1498,18 +1498,16 @@ nmi_restore: iretq SYM_CODE_END(asm_exc_nmi) -#ifndef CONFIG_IA32_EMULATION /* * This handles SYSCALL from 32-bit code. There is no way to program * MSRs to fully disable 32-bit SYSCALL. */ -SYM_CODE_START(ignore_sysret) +SYM_CODE_START(entry_SYSCALL32_ignore) UNWIND_HINT_EMPTY ENDBR mov $-ENOSYS, %eax sysretl -SYM_CODE_END(ignore_sysret) -#endif +SYM_CODE_END(entry_SYSCALL32_ignore) .pushsection .text, "ax" SYM_CODE_START(rewind_stack_and_make_dead) diff --git a/arch/x86/entry/entry_64_compat.S b/arch/x86/entry/entry_64_compat.S index e7ae79e557a42..130751fd2b3cb 100644 --- a/arch/x86/entry/entry_64_compat.S +++ b/arch/x86/entry/entry_64_compat.S @@ -274,80 +274,3 @@ SYM_INNER_LABEL(entry_SYSRETL_compat_unsafe_stack, SYM_L_GLOBAL) sysretl SYM_INNER_LABEL(entry_SYSRETL_compat_end, SYM_L_GLOBAL) SYM_CODE_END(entry_SYSCALL_compat) - -/* - * 32-bit legacy system call entry. - * - * 32-bit x86 Linux system calls traditionally used the INT $0x80 - * instruction. INT $0x80 lands here. - * - * This entry point can be used by 32-bit and 64-bit programs to perform - * 32-bit system calls. Instances of INT $0x80 can be found inline in - * various programs and libraries. It is also used by the vDSO's - * __kernel_vsyscall fallback for hardware that doesn't support a faster - * entry method. Restarted 32-bit system calls also fall back to INT - * $0x80 regardless of what instruction was originally used to do the - * system call. - * - * This is considered a slow path. It is not used by most libc - * implementations on modern hardware except during process startup. - * - * Arguments: - * eax system call number - * ebx arg1 - * ecx arg2 - * edx arg3 - * esi arg4 - * edi arg5 - * ebp arg6 - */ -SYM_CODE_START(entry_INT80_compat) - UNWIND_HINT_EMPTY - ENDBR - /* - * Interrupts are off on entry. - */ - ASM_CLAC /* Do this early to minimize exposure */ - SWAPGS - - /* - * User tracing code (ptrace or signal handlers) might assume that - * the saved RAX contains a 32-bit number when we're invoking a 32-bit - * syscall. Just in case the high bits are nonzero, zero-extend - * the syscall number. (This could almost certainly be deleted - * with no ill effects.) - */ - movl %eax, %eax - - /* switch to thread stack expects orig_ax and rdi to be pushed */ - pushq %rax /* pt_regs->orig_ax */ - - /* Need to switch before accessing the thread stack. */ - SWITCH_TO_KERNEL_CR3 scratch_reg=%rax - - /* In the Xen PV case we already run on the thread stack. */ - ALTERNATIVE "", "jmp .Lint80_keep_stack", X86_FEATURE_XENPV - - movq %rsp, %rax - movq PER_CPU_VAR(cpu_current_top_of_stack), %rsp - - pushq 5*8(%rax) /* regs->ss */ - pushq 4*8(%rax) /* regs->rsp */ - pushq 3*8(%rax) /* regs->eflags */ - pushq 2*8(%rax) /* regs->cs */ - pushq 1*8(%rax) /* regs->ip */ - pushq 0*8(%rax) /* regs->orig_ax */ -.Lint80_keep_stack: - - PUSH_AND_CLEAR_REGS rax=$-ENOSYS - UNWIND_HINT_REGS - - cld - - IBRS_ENTER - UNTRAIN_RET - - movq %rsp, %rdi - call do_int80_syscall_32 - jmp swapgs_restore_regs_and_return_to_usermode -SYM_CODE_END(entry_INT80_compat) diff --git a/arch/x86/include/asm/ia32.h b/arch/x86/include/asm/ia32.h index 2c5f7861d373c..9805629479d96 100644 --- a/arch/x86/include/asm/ia32.h +++ b/arch/x86/include/asm/ia32.h @@ -68,6 +68,27 @@ extern void ia32_pick_mmap_layout(struct mm_struct *mm); #endif -#endif /* !CONFIG_IA32_SUPPORT */ +extern bool __ia32_enabled; + +static inline bool ia32_enabled(void) +{ + return __ia32_enabled; +} + +static inline void ia32_disable(void) +{ + __ia32_enabled = false; +} + +#else /* !CONFIG_IA32_EMULATION */ + +static inline bool ia32_enabled(void) +{ + return IS_ENABLED(CONFIG_X86_32); +} + +static inline void ia32_disable(void) {} + +#endif #endif /* _ASM_X86_IA32_H */ diff --git a/arch/x86/include/asm/idtentry.h b/arch/x86/include/asm/idtentry.h index 72184b0b2219e..fca710a93eb9c 100644 --- a/arch/x86/include/asm/idtentry.h +++ b/arch/x86/include/asm/idtentry.h @@ -569,6 +569,10 @@ DECLARE_IDTENTRY_RAW(X86_TRAP_UD, exc_invalid_op); DECLARE_IDTENTRY_RAW(X86_TRAP_BP, exc_int3); DECLARE_IDTENTRY_RAW_ERRORCODE(X86_TRAP_PF, exc_page_fault); +#if defined(CONFIG_IA32_EMULATION) +DECLARE_IDTENTRY_RAW(IA32_SYSCALL_VECTOR, int80_emulation); +#endif + #ifdef CONFIG_X86_MCE #ifdef CONFIG_X86_64 DECLARE_IDTENTRY_MCE(X86_TRAP_MC, exc_machine_check); diff --git a/arch/x86/include/asm/irq_stack.h b/arch/x86/include/asm/irq_stack.h index f8958fcb695eb..63f818aedf770 100644 --- a/arch/x86/include/asm/irq_stack.h +++ b/arch/x86/include/asm/irq_stack.h @@ -59,7 +59,7 @@ * the output constraints to make the compiler aware that R11 cannot be * reused after the asm() statement. * - * For builds with CONFIG_UNWIND_FRAME_POINTER ASM_CALL_CONSTRAINT is + * For builds with CONFIG_UNWINDER_FRAME_POINTER, ASM_CALL_CONSTRAINT is * required as well as this prevents certain creative GCC variants from * misplacing the ASM code. * diff --git a/arch/x86/include/asm/page_32.h b/arch/x86/include/asm/page_32.h index 94dbd51df58f8..b13f8488ac854 100644 --- a/arch/x86/include/asm/page_32.h +++ b/arch/x86/include/asm/page_32.h @@ -43,7 +43,7 @@ static inline void copy_page(void *to, void *from) { memcpy(to, from, PAGE_SIZE); } -#endif /* CONFIG_X86_3DNOW */ +#endif /* CONFIG_X86_USE_3DNOW */ #endif /* !__ASSEMBLY__ */ #endif /* _ASM_X86_PAGE_32_H */ diff --git a/arch/x86/include/asm/processor.h b/arch/x86/include/asm/processor.h index 3016e147f253f..ff290c94ad063 100644 --- a/arch/x86/include/asm/processor.h +++ b/arch/x86/include/asm/processor.h @@ -461,7 +461,7 @@ static inline unsigned long cpu_kernelmode_gs_base(int cpu) DECLARE_PER_CPU(void *, hardirq_stack_ptr); DECLARE_PER_CPU(bool, hardirq_stack_inuse); -extern asmlinkage void ignore_sysret(void); +extern asmlinkage void entry_SYSCALL32_ignore(void); /* Save actual FS/GS selectors and bases to current->thread */ void current_save_fsgs(void); diff --git a/arch/x86/include/asm/proto.h b/arch/x86/include/asm/proto.h index f042cfc9938f4..6bca4344fd092 100644 --- a/arch/x86/include/asm/proto.h +++ b/arch/x86/include/asm/proto.h @@ -32,10 +32,9 @@ void entry_SYSCALL_compat(void); void entry_SYSCALL_compat_safe_stack(void); void entry_SYSRETL_compat_unsafe_stack(void); void entry_SYSRETL_compat_end(void); -void entry_INT80_compat(void); -#ifdef CONFIG_XEN_PV -void xen_entry_INT80_compat(void); -#endif +#else /* !CONFIG_IA32_EMULATION */ +#define entry_SYSCALL_compat NULL +#define entry_SYSENTER_compat NULL #endif void x86_configure_nx(void); diff --git a/arch/x86/include/asm/uaccess.h b/arch/x86/include/asm/uaccess.h index 538646ec8027d..bbd2bb0d3beeb 100644 --- a/arch/x86/include/asm/uaccess.h +++ b/arch/x86/include/asm/uaccess.h @@ -379,7 +379,7 @@ do { \ : [umem] "m" (__m(addr)), \ "0" (err)) -#endif // CONFIG_CC_ASM_GOTO_OUTPUT +#endif // CONFIG_CC_HAS_ASM_GOTO_OUTPUT #ifdef CONFIG_CC_HAS_ASM_GOTO_TIED_OUTPUT #define __try_cmpxchg_user_asm(itype, ltype, _ptr, _pold, _new, label) ({ \ diff --git a/arch/x86/kernel/cpu/common.c b/arch/x86/kernel/cpu/common.c index c4483102aaffc..deb46089f7636 100644 --- a/arch/x86/kernel/cpu/common.c +++ b/arch/x86/kernel/cpu/common.c @@ -59,6 +59,7 @@ #include #include #include +#include #include #include @@ -2012,24 +2013,24 @@ void syscall_init(void) wrmsr(MSR_STAR, 0, (__USER32_CS << 16) | __KERNEL_CS); wrmsrl(MSR_LSTAR, (unsigned long)entry_SYSCALL_64); -#ifdef CONFIG_IA32_EMULATION - wrmsrl(MSR_CSTAR, (unsigned long)entry_SYSCALL_compat); - /* - * This only works on Intel CPUs. - * On AMD CPUs these MSRs are 32-bit, CPU truncates MSR_IA32_SYSENTER_EIP. - * This does not cause SYSENTER to jump to the wrong location, because - * AMD doesn't allow SYSENTER in long mode (either 32- or 64-bit). - */ - wrmsrl_safe(MSR_IA32_SYSENTER_CS, (u64)__KERNEL_CS); - wrmsrl_safe(MSR_IA32_SYSENTER_ESP, - (unsigned long)(cpu_entry_stack(smp_processor_id()) + 1)); - wrmsrl_safe(MSR_IA32_SYSENTER_EIP, (u64)entry_SYSENTER_compat); -#else - wrmsrl(MSR_CSTAR, (unsigned long)ignore_sysret); - wrmsrl_safe(MSR_IA32_SYSENTER_CS, (u64)GDT_ENTRY_INVALID_SEG); - wrmsrl_safe(MSR_IA32_SYSENTER_ESP, 0ULL); - wrmsrl_safe(MSR_IA32_SYSENTER_EIP, 0ULL); -#endif + if (ia32_enabled()) { + wrmsrl(MSR_CSTAR, (unsigned long)entry_SYSCALL_compat); + /* + * This only works on Intel CPUs. + * On AMD CPUs these MSRs are 32-bit, CPU truncates MSR_IA32_SYSENTER_EIP. + * This does not cause SYSENTER to jump to the wrong location, because + * AMD doesn't allow SYSENTER in long mode (either 32- or 64-bit). + */ + wrmsrl_safe(MSR_IA32_SYSENTER_CS, (u64)__KERNEL_CS); + wrmsrl_safe(MSR_IA32_SYSENTER_ESP, + (unsigned long)(cpu_entry_stack(smp_processor_id()) + 1)); + wrmsrl_safe(MSR_IA32_SYSENTER_EIP, (u64)entry_SYSENTER_compat); + } else { + wrmsrl(MSR_CSTAR, (unsigned long)entry_SYSCALL32_ignore); + wrmsrl_safe(MSR_IA32_SYSENTER_CS, (u64)GDT_ENTRY_INVALID_SEG); + wrmsrl_safe(MSR_IA32_SYSENTER_ESP, 0ULL); + wrmsrl_safe(MSR_IA32_SYSENTER_EIP, 0ULL); + } /* * Flags to clear on syscall; clear as much as possible diff --git a/arch/x86/kernel/idt.c b/arch/x86/kernel/idt.c index a58c6bc1cd68c..06908a64db416 100644 --- a/arch/x86/kernel/idt.c +++ b/arch/x86/kernel/idt.c @@ -10,6 +10,7 @@ #include #include #include +#include #include #define DPL0 0x0 @@ -116,8 +117,11 @@ static const __initconst struct idt_data def_idts[] = { #endif SYSG(X86_TRAP_OF, asm_exc_overflow), +}; + +static const struct idt_data ia32_idt[] __initconst = { #if defined(CONFIG_IA32_EMULATION) - SYSG(IA32_SYSCALL_VECTOR, entry_INT80_compat), + SYSG(IA32_SYSCALL_VECTOR, asm_int80_emulation), #elif defined(CONFIG_X86_32) SYSG(IA32_SYSCALL_VECTOR, entry_INT80_32), #endif @@ -226,6 +230,9 @@ void __init idt_setup_early_traps(void) void __init idt_setup_traps(void) { idt_setup_from_table(idt_table, def_idts, ARRAY_SIZE(def_idts), true); + + if (ia32_enabled()) + idt_setup_from_table(idt_table, ia32_idt, ARRAY_SIZE(ia32_idt), true); } #ifdef CONFIG_X86_64 diff --git a/arch/x86/kernel/sev-shared.c b/arch/x86/kernel/sev-shared.c index 3a5b0c9c4fccc..cc1d91393192b 100644 --- a/arch/x86/kernel/sev-shared.c +++ b/arch/x86/kernel/sev-shared.c @@ -10,8 +10,13 @@ */ #ifndef __BOOT_COMPRESSED -#define error(v) pr_err(v) -#define has_cpuflag(f) boot_cpu_has(f) +#define error(v) pr_err(v) +#define has_cpuflag(f) boot_cpu_has(f) +#define sev_printk(fmt, ...) printk(fmt, ##__VA_ARGS__) +#define sev_printk_rtl(fmt, ...) printk_ratelimited(fmt, ##__VA_ARGS__) +#else +#define sev_printk(fmt, ...) +#define sev_printk_rtl(fmt, ...) #endif /* I/O parameters for CPUID-related helpers */ @@ -531,6 +536,7 @@ void __init do_vc_no_ghcb(struct pt_regs *regs, unsigned long exit_code) { unsigned int subfn = lower_bits(regs->cx, 32); unsigned int fn = lower_bits(regs->ax, 32); + u16 opcode = *(unsigned short *)regs->ip; struct cpuid_leaf leaf; int ret; @@ -538,6 +544,10 @@ void __init do_vc_no_ghcb(struct pt_regs *regs, unsigned long exit_code) if (exit_code != SVM_EXIT_CPUID) goto fail; + /* Is it really a CPUID insn? */ + if (opcode != 0xa20f) + goto fail; + leaf.fn = fn; leaf.subfn = subfn; @@ -991,3 +1001,94 @@ static void __init setup_cpuid_table(const struct cc_blob_sev_info *cc_info) cpuid_ext_range_max = fn->eax; } } + +static enum es_result vc_check_opcode_bytes(struct es_em_ctxt *ctxt, + unsigned long exit_code) +{ + unsigned int opcode = (unsigned int)ctxt->insn.opcode.value; + u8 modrm = ctxt->insn.modrm.value; + + switch (exit_code) { + + case SVM_EXIT_IOIO: + case SVM_EXIT_NPF: + /* handled separately */ + return ES_OK; + + case SVM_EXIT_CPUID: + if (opcode == 0xa20f) + return ES_OK; + break; + + case SVM_EXIT_INVD: + if (opcode == 0x080f) + return ES_OK; + break; + + case SVM_EXIT_MONITOR: + /* MONITOR and MONITORX instructions generate the same error code */ + if (opcode == 0x010f && (modrm == 0xc8 || modrm == 0xfa)) + return ES_OK; + break; + + case SVM_EXIT_MWAIT: + /* MWAIT and MWAITX instructions generate the same error code */ + if (opcode == 0x010f && (modrm == 0xc9 || modrm == 0xfb)) + return ES_OK; + break; + + case SVM_EXIT_MSR: + /* RDMSR */ + if (opcode == 0x320f || + /* WRMSR */ + opcode == 0x300f) + return ES_OK; + break; + + case SVM_EXIT_RDPMC: + if (opcode == 0x330f) + return ES_OK; + break; + + case SVM_EXIT_RDTSC: + if (opcode == 0x310f) + return ES_OK; + break; + + case SVM_EXIT_RDTSCP: + if (opcode == 0x010f && modrm == 0xf9) + return ES_OK; + break; + + case SVM_EXIT_READ_DR7: + if (opcode == 0x210f && + X86_MODRM_REG(ctxt->insn.modrm.value) == 7) + return ES_OK; + break; + + case SVM_EXIT_VMMCALL: + if (opcode == 0x010f && modrm == 0xd9) + return ES_OK; + + break; + + case SVM_EXIT_WRITE_DR7: + if (opcode == 0x230f && + X86_MODRM_REG(ctxt->insn.modrm.value) == 7) + return ES_OK; + break; + + case SVM_EXIT_WBINVD: + if (opcode == 0x90f) + return ES_OK; + break; + + default: + break; + } + + sev_printk(KERN_ERR "Wrong/unhandled opcode bytes: 0x%x, exit_code: 0x%lx, rIP: 0x%lx\n", + opcode, exit_code, ctxt->regs->ip); + + return ES_UNSUPPORTED; +} diff --git a/arch/x86/kernel/sev.c b/arch/x86/kernel/sev.c index 4fe4c8ecf4c95..aa2fc339878be 100644 --- a/arch/x86/kernel/sev.c +++ b/arch/x86/kernel/sev.c @@ -1738,7 +1738,10 @@ static enum es_result vc_handle_exitcode(struct es_em_ctxt *ctxt, struct ghcb *ghcb, unsigned long exit_code) { - enum es_result result; + enum es_result result = vc_check_opcode_bytes(ctxt, exit_code); + + if (result != ES_OK) + return result; switch (exit_code) { case SVM_EXIT_READ_DR7: diff --git a/arch/x86/mm/mem_encrypt_amd.c b/arch/x86/mm/mem_encrypt_amd.c index e8f7953fda83a..c8b3bd1c406e8 100644 --- a/arch/x86/mm/mem_encrypt_amd.c +++ b/arch/x86/mm/mem_encrypt_amd.c @@ -32,6 +32,7 @@ #include #include #include +#include #include "mm_internal.h" @@ -499,6 +500,16 @@ void __init sme_early_init(void) x86_platform.guest.enc_status_change_finish = amd_enc_status_change_finish; x86_platform.guest.enc_tlb_flush_required = amd_enc_tlb_flush_required; x86_platform.guest.enc_cache_flush_required = amd_enc_cache_flush_required; + + /* + * The VMM is capable of injecting interrupt 0x80 and triggering the + * compatibility syscall path. + * + * By default, the 32-bit emulation is disabled in order to ensure + * the safety of the VM. + */ + if (sev_status & MSR_AMD64_SEV_ENABLED) + ia32_disable(); } void __init mem_encrypt_free_decrypted_mem(void) diff --git a/arch/x86/xen/enlighten_pv.c b/arch/x86/xen/enlighten_pv.c index c191817bd455f..9c4f4f89759a8 100644 --- a/arch/x86/xen/enlighten_pv.c +++ b/arch/x86/xen/enlighten_pv.c @@ -637,7 +637,7 @@ static struct trap_array_entry trap_array[] = { TRAP_ENTRY(exc_int3, false ), TRAP_ENTRY(exc_overflow, false ), #ifdef CONFIG_IA32_EMULATION - { entry_INT80_compat, xen_entry_INT80_compat, false }, + TRAP_ENTRY(int80_emulation, false ), #endif TRAP_ENTRY(exc_page_fault, false ), TRAP_ENTRY(exc_divide_error, false ), diff --git a/arch/x86/xen/xen-asm.S b/arch/x86/xen/xen-asm.S index 6bf9d45b91784..accea4262240d 100644 --- a/arch/x86/xen/xen-asm.S +++ b/arch/x86/xen/xen-asm.S @@ -156,7 +156,7 @@ xen_pv_trap asm_xenpv_exc_machine_check #endif /* CONFIG_X86_MCE */ xen_pv_trap asm_exc_simd_coprocessor_error #ifdef CONFIG_IA32_EMULATION -xen_pv_trap entry_INT80_compat +xen_pv_trap asm_int80_emulation #endif xen_pv_trap asm_exc_xen_unknown_trap xen_pv_trap asm_exc_xen_hypervisor_callback