diff options
Diffstat (limited to 'arch/x86/mm/extable.c')
-rw-r--r-- | arch/x86/mm/extable.c | 123 |
1 files changed, 52 insertions, 71 deletions
diff --git a/arch/x86/mm/extable.c b/arch/x86/mm/extable.c index d9a1046f3a98..5db46df409b5 100644 --- a/arch/x86/mm/extable.c +++ b/arch/x86/mm/extable.c @@ -9,40 +9,25 @@ #include <asm/traps.h> #include <asm/kdebug.h> -typedef bool (*ex_handler_t)(const struct exception_table_entry *, - struct pt_regs *, int, unsigned long, - unsigned long); - static inline unsigned long ex_fixup_addr(const struct exception_table_entry *x) { return (unsigned long)&x->fixup + x->fixup; } -static inline ex_handler_t -ex_fixup_handler(const struct exception_table_entry *x) -{ - return (ex_handler_t)((unsigned long)&x->handler + x->handler); -} -__visible bool ex_handler_default(const struct exception_table_entry *fixup, - struct pt_regs *regs, int trapnr, - unsigned long error_code, - unsigned long fault_addr) +static bool ex_handler_default(const struct exception_table_entry *fixup, + struct pt_regs *regs) { regs->ip = ex_fixup_addr(fixup); return true; } -EXPORT_SYMBOL(ex_handler_default); -__visible bool ex_handler_fault(const struct exception_table_entry *fixup, - struct pt_regs *regs, int trapnr, - unsigned long error_code, - unsigned long fault_addr) +static bool ex_handler_fault(const struct exception_table_entry *fixup, + struct pt_regs *regs, int trapnr) { regs->ax = trapnr; - return ex_handler_default(fixup, regs, trapnr, error_code, fault_addr); + return ex_handler_default(fixup, regs); } -EXPORT_SYMBOL_GPL(ex_handler_fault); /* * Handler for when we fail to restore a task's FPU state. We should never get @@ -54,10 +39,8 @@ EXPORT_SYMBOL_GPL(ex_handler_fault); * of vulnerability by restoring from the initial state (essentially, zeroing * out all the FPU registers) if we can't restore from the task's FPU state. */ -__visible bool ex_handler_fprestore(const struct exception_table_entry *fixup, - struct pt_regs *regs, int trapnr, - unsigned long error_code, - unsigned long fault_addr) +static bool ex_handler_fprestore(const struct exception_table_entry *fixup, + struct pt_regs *regs) { regs->ip = ex_fixup_addr(fixup); @@ -67,32 +50,23 @@ __visible bool ex_handler_fprestore(const struct exception_table_entry *fixup, __restore_fpregs_from_fpstate(&init_fpstate, xfeatures_mask_fpstate()); return true; } -EXPORT_SYMBOL_GPL(ex_handler_fprestore); -__visible bool ex_handler_uaccess(const struct exception_table_entry *fixup, - struct pt_regs *regs, int trapnr, - unsigned long error_code, - unsigned long fault_addr) +static bool ex_handler_uaccess(const struct exception_table_entry *fixup, + struct pt_regs *regs, int trapnr) { WARN_ONCE(trapnr == X86_TRAP_GP, "General protection fault in user access. Non-canonical address?"); - return ex_handler_default(fixup, regs, trapnr, error_code, fault_addr); + return ex_handler_default(fixup, regs); } -EXPORT_SYMBOL(ex_handler_uaccess); -__visible bool ex_handler_copy(const struct exception_table_entry *fixup, - struct pt_regs *regs, int trapnr, - unsigned long error_code, - unsigned long fault_addr) +static bool ex_handler_copy(const struct exception_table_entry *fixup, + struct pt_regs *regs, int trapnr) { WARN_ONCE(trapnr == X86_TRAP_GP, "General protection fault in user access. Non-canonical address?"); - return ex_handler_fault(fixup, regs, trapnr, error_code, fault_addr); + return ex_handler_fault(fixup, regs, trapnr); } -EXPORT_SYMBOL(ex_handler_copy); -__visible bool ex_handler_rdmsr_unsafe(const struct exception_table_entry *fixup, - struct pt_regs *regs, int trapnr, - unsigned long error_code, - unsigned long fault_addr) +static bool ex_handler_rdmsr_unsafe(const struct exception_table_entry *fixup, + struct pt_regs *regs) { if (pr_warn_once("unchecked MSR access error: RDMSR from 0x%x at rIP: 0x%lx (%pS)\n", (unsigned int)regs->cx, regs->ip, (void *)regs->ip)) @@ -101,14 +75,11 @@ __visible bool ex_handler_rdmsr_unsafe(const struct exception_table_entry *fixup /* Pretend that the read succeeded and returned 0. */ regs->ax = 0; regs->dx = 0; - return ex_handler_default(fixup, regs, trapnr, error_code, fault_addr); + return ex_handler_default(fixup, regs); } -EXPORT_SYMBOL(ex_handler_rdmsr_unsafe); -__visible bool ex_handler_wrmsr_unsafe(const struct exception_table_entry *fixup, - struct pt_regs *regs, int trapnr, - unsigned long error_code, - unsigned long fault_addr) +static bool ex_handler_wrmsr_unsafe(const struct exception_table_entry *fixup, + struct pt_regs *regs) { if (pr_warn_once("unchecked MSR access error: WRMSR to 0x%x (tried to write 0x%08x%08x) at rIP: 0x%lx (%pS)\n", (unsigned int)regs->cx, (unsigned int)regs->dx, @@ -116,44 +87,29 @@ __visible bool ex_handler_wrmsr_unsafe(const struct exception_table_entry *fixup show_stack_regs(regs); /* Pretend that the write succeeded. */ - return ex_handler_default(fixup, regs, trapnr, error_code, fault_addr); + return ex_handler_default(fixup, regs); } -EXPORT_SYMBOL(ex_handler_wrmsr_unsafe); -__visible bool ex_handler_clear_fs(const struct exception_table_entry *fixup, - struct pt_regs *regs, int trapnr, - unsigned long error_code, - unsigned long fault_addr) +static bool ex_handler_clear_fs(const struct exception_table_entry *fixup, + struct pt_regs *regs) { if (static_cpu_has(X86_BUG_NULL_SEG)) asm volatile ("mov %0, %%fs" : : "rm" (__USER_DS)); asm volatile ("mov %0, %%fs" : : "rm" (0)); - return ex_handler_default(fixup, regs, trapnr, error_code, fault_addr); + return ex_handler_default(fixup, regs); } -EXPORT_SYMBOL(ex_handler_clear_fs); -enum handler_type ex_get_fault_handler_type(unsigned long ip) +int ex_get_fixup_type(unsigned long ip) { - const struct exception_table_entry *e; - ex_handler_t handler; + const struct exception_table_entry *e = search_exception_tables(ip); - e = search_exception_tables(ip); - if (!e) - return EX_HANDLER_NONE; - handler = ex_fixup_handler(e); - if (handler == ex_handler_fault) - return EX_HANDLER_FAULT; - else if (handler == ex_handler_uaccess || handler == ex_handler_copy) - return EX_HANDLER_UACCESS; - else - return EX_HANDLER_OTHER; + return e ? e->type : EX_TYPE_NONE; } int fixup_exception(struct pt_regs *regs, int trapnr, unsigned long error_code, unsigned long fault_addr) { const struct exception_table_entry *e; - ex_handler_t handler; #ifdef CONFIG_PNPBIOS if (unlikely(SEGMENT_IS_PNP_CODE(regs->cs))) { @@ -173,8 +129,33 @@ int fixup_exception(struct pt_regs *regs, int trapnr, unsigned long error_code, if (!e) return 0; - handler = ex_fixup_handler(e); - return handler(e, regs, trapnr, error_code, fault_addr); + switch (e->type) { + case EX_TYPE_DEFAULT: + return ex_handler_default(e, regs); + case EX_TYPE_FAULT: + return ex_handler_fault(e, regs, trapnr); + case EX_TYPE_UACCESS: + return ex_handler_uaccess(e, regs, trapnr); + case EX_TYPE_COPY: + return ex_handler_copy(e, regs, trapnr); + case EX_TYPE_CLEAR_FS: + return ex_handler_clear_fs(e, regs); + case EX_TYPE_FPU_RESTORE: + return ex_handler_fprestore(e, regs); + case EX_TYPE_RDMSR: + return ex_handler_rdmsr_unsafe(e, regs); + case EX_TYPE_WRMSR: + return ex_handler_wrmsr_unsafe(e, regs); + case EX_TYPE_BPF: + return ex_handler_bpf(e, regs); + case EX_TYPE_RDMSR_IN_MCE: + ex_handler_msr_mce(regs, false); + break; + case EX_TYPE_WRMSR_IN_MCE: + ex_handler_msr_mce(regs, true); + break; + } + BUG(); } extern unsigned int early_recursion_flag; |