|  | /* | 
|  | *  Copyright (C) 1991, 1992  Linus Torvalds | 
|  | *  Copyright (C) 2000, 2001, 2002 Andi Kleen, SuSE Labs | 
|  | */ | 
|  | #include <linux/kallsyms.h> | 
|  | #include <linux/kprobes.h> | 
|  | #include <linux/uaccess.h> | 
|  | #include <linux/utsname.h> | 
|  | #include <linux/hardirq.h> | 
|  | #include <linux/kdebug.h> | 
|  | #include <linux/module.h> | 
|  | #include <linux/ptrace.h> | 
|  | #include <linux/kexec.h> | 
|  | #include <linux/bug.h> | 
|  | #include <linux/nmi.h> | 
|  | #include <linux/sysfs.h> | 
|  |  | 
|  | #include <asm/stacktrace.h> | 
|  |  | 
|  | #define STACKSLOTS_PER_LINE 8 | 
|  | #define get_bp(bp) asm("movl %%ebp, %0" : "=r" (bp) :) | 
|  |  | 
|  | int panic_on_unrecovered_nmi; | 
|  | int kstack_depth_to_print = 3 * STACKSLOTS_PER_LINE; | 
|  | static unsigned int code_bytes = 64; | 
|  | static int die_counter; | 
|  |  | 
|  | void printk_address(unsigned long address, int reliable) | 
|  | { | 
|  | printk(" [<%p>] %s%pS\n", (void *) address, | 
|  | reliable ? "" : "? ", (void *) address); | 
|  | } | 
|  |  | 
|  | static inline int valid_stack_ptr(struct thread_info *tinfo, | 
|  | void *p, unsigned int size, void *end) | 
|  | { | 
|  | void *t = tinfo; | 
|  | if (end) { | 
|  | if (p < end && p >= (end-THREAD_SIZE)) | 
|  | return 1; | 
|  | else | 
|  | return 0; | 
|  | } | 
|  | return p > t && p < t + THREAD_SIZE - size; | 
|  | } | 
|  |  | 
|  | /* The form of the top of the frame on the stack */ | 
|  | struct stack_frame { | 
|  | struct stack_frame *next_frame; | 
|  | unsigned long return_address; | 
|  | }; | 
|  |  | 
|  | static inline unsigned long | 
|  | print_context_stack(struct thread_info *tinfo, | 
|  | unsigned long *stack, unsigned long bp, | 
|  | const struct stacktrace_ops *ops, void *data, | 
|  | unsigned long *end) | 
|  | { | 
|  | struct stack_frame *frame = (struct stack_frame *)bp; | 
|  |  | 
|  | while (valid_stack_ptr(tinfo, stack, sizeof(*stack), end)) { | 
|  | unsigned long addr; | 
|  |  | 
|  | addr = *stack; | 
|  | if (__kernel_text_address(addr)) { | 
|  | if ((unsigned long) stack == bp + sizeof(long)) { | 
|  | ops->address(data, addr, 1); | 
|  | frame = frame->next_frame; | 
|  | bp = (unsigned long) frame; | 
|  | } else { | 
|  | ops->address(data, addr, bp == 0); | 
|  | } | 
|  | } | 
|  | stack++; | 
|  | } | 
|  | return bp; | 
|  | } | 
|  |  | 
|  | void dump_trace(struct task_struct *task, struct pt_regs *regs, | 
|  | unsigned long *stack, unsigned long bp, | 
|  | const struct stacktrace_ops *ops, void *data) | 
|  | { | 
|  | if (!task) | 
|  | task = current; | 
|  |  | 
|  | if (!stack) { | 
|  | unsigned long dummy; | 
|  | stack = &dummy; | 
|  | if (task && task != current) | 
|  | stack = (unsigned long *)task->thread.sp; | 
|  | } | 
|  |  | 
|  | #ifdef CONFIG_FRAME_POINTER | 
|  | if (!bp) { | 
|  | if (task == current) { | 
|  | /* Grab bp right from our regs */ | 
|  | get_bp(bp); | 
|  | } else { | 
|  | /* bp is the last reg pushed by switch_to */ | 
|  | bp = *(unsigned long *) task->thread.sp; | 
|  | } | 
|  | } | 
|  | #endif | 
|  |  | 
|  | for (;;) { | 
|  | struct thread_info *context; | 
|  |  | 
|  | context = (struct thread_info *) | 
|  | ((unsigned long)stack & (~(THREAD_SIZE - 1))); | 
|  | bp = print_context_stack(context, stack, bp, ops, data, NULL); | 
|  |  | 
|  | stack = (unsigned long *)context->previous_esp; | 
|  | if (!stack) | 
|  | break; | 
|  | if (ops->stack(data, "IRQ") < 0) | 
|  | break; | 
|  | touch_nmi_watchdog(); | 
|  | } | 
|  | } | 
|  | EXPORT_SYMBOL(dump_trace); | 
|  |  | 
|  | static void | 
|  | print_trace_warning_symbol(void *data, char *msg, unsigned long symbol) | 
|  | { | 
|  | printk(data); | 
|  | print_symbol(msg, symbol); | 
|  | printk("\n"); | 
|  | } | 
|  |  | 
|  | static void print_trace_warning(void *data, char *msg) | 
|  | { | 
|  | printk("%s%s\n", (char *)data, msg); | 
|  | } | 
|  |  | 
|  | static int print_trace_stack(void *data, char *name) | 
|  | { | 
|  | printk("%s <%s> ", (char *)data, name); | 
|  | return 0; | 
|  | } | 
|  |  | 
|  | /* | 
|  | * Print one address/symbol entries per line. | 
|  | */ | 
|  | static void print_trace_address(void *data, unsigned long addr, int reliable) | 
|  | { | 
|  | touch_nmi_watchdog(); | 
|  | printk(data); | 
|  | printk_address(addr, reliable); | 
|  | } | 
|  |  | 
|  | static const struct stacktrace_ops print_trace_ops = { | 
|  | .warning = print_trace_warning, | 
|  | .warning_symbol = print_trace_warning_symbol, | 
|  | .stack = print_trace_stack, | 
|  | .address = print_trace_address, | 
|  | }; | 
|  |  | 
|  | static void | 
|  | show_trace_log_lvl(struct task_struct *task, struct pt_regs *regs, | 
|  | unsigned long *stack, unsigned long bp, char *log_lvl) | 
|  | { | 
|  | printk("%sCall Trace:\n", log_lvl); | 
|  | dump_trace(task, regs, stack, bp, &print_trace_ops, log_lvl); | 
|  | } | 
|  |  | 
|  | void show_trace(struct task_struct *task, struct pt_regs *regs, | 
|  | unsigned long *stack, unsigned long bp) | 
|  | { | 
|  | show_trace_log_lvl(task, regs, stack, bp, ""); | 
|  | } | 
|  |  | 
|  | static void | 
|  | show_stack_log_lvl(struct task_struct *task, struct pt_regs *regs, | 
|  | unsigned long *sp, unsigned long bp, char *log_lvl) | 
|  | { | 
|  | unsigned long *stack; | 
|  | int i; | 
|  |  | 
|  | if (sp == NULL) { | 
|  | if (task) | 
|  | sp = (unsigned long *)task->thread.sp; | 
|  | else | 
|  | sp = (unsigned long *)&sp; | 
|  | } | 
|  |  | 
|  | stack = sp; | 
|  | for (i = 0; i < kstack_depth_to_print; i++) { | 
|  | if (kstack_end(stack)) | 
|  | break; | 
|  | if (i && ((i % STACKSLOTS_PER_LINE) == 0)) | 
|  | printk("\n%s", log_lvl); | 
|  | printk(" %08lx", *stack++); | 
|  | touch_nmi_watchdog(); | 
|  | } | 
|  | printk("\n"); | 
|  | show_trace_log_lvl(task, regs, sp, bp, log_lvl); | 
|  | } | 
|  |  | 
|  | void show_stack(struct task_struct *task, unsigned long *sp) | 
|  | { | 
|  | show_stack_log_lvl(task, NULL, sp, 0, ""); | 
|  | } | 
|  |  | 
|  | /* | 
|  | * The architecture-independent dump_stack generator | 
|  | */ | 
|  | void dump_stack(void) | 
|  | { | 
|  | unsigned long bp = 0; | 
|  | unsigned long stack; | 
|  |  | 
|  | #ifdef CONFIG_FRAME_POINTER | 
|  | if (!bp) | 
|  | get_bp(bp); | 
|  | #endif | 
|  |  | 
|  | printk("Pid: %d, comm: %.20s %s %s %.*s\n", | 
|  | current->pid, current->comm, print_tainted(), | 
|  | init_utsname()->release, | 
|  | (int)strcspn(init_utsname()->version, " "), | 
|  | init_utsname()->version); | 
|  | show_trace(NULL, NULL, &stack, bp); | 
|  | } | 
|  |  | 
|  | EXPORT_SYMBOL(dump_stack); | 
|  |  | 
|  | void show_registers(struct pt_regs *regs) | 
|  | { | 
|  | int i; | 
|  |  | 
|  | print_modules(); | 
|  | __show_regs(regs, 0); | 
|  |  | 
|  | printk(KERN_EMERG "Process %.*s (pid: %d, ti=%p task=%p task.ti=%p)\n", | 
|  | TASK_COMM_LEN, current->comm, task_pid_nr(current), | 
|  | current_thread_info(), current, task_thread_info(current)); | 
|  | /* | 
|  | * When in-kernel, we also print out the stack and code at the | 
|  | * time of the fault.. | 
|  | */ | 
|  | if (!user_mode_vm(regs)) { | 
|  | unsigned int code_prologue = code_bytes * 43 / 64; | 
|  | unsigned int code_len = code_bytes; | 
|  | unsigned char c; | 
|  | u8 *ip; | 
|  |  | 
|  | printk(KERN_EMERG "Stack:\n"); | 
|  | show_stack_log_lvl(NULL, regs, ®s->sp, | 
|  | 0, KERN_EMERG); | 
|  |  | 
|  | printk(KERN_EMERG "Code: "); | 
|  |  | 
|  | ip = (u8 *)regs->ip - code_prologue; | 
|  | if (ip < (u8 *)PAGE_OFFSET || probe_kernel_address(ip, c)) { | 
|  | /* try starting at IP */ | 
|  | ip = (u8 *)regs->ip; | 
|  | code_len = code_len - code_prologue + 1; | 
|  | } | 
|  | for (i = 0; i < code_len; i++, ip++) { | 
|  | if (ip < (u8 *)PAGE_OFFSET || | 
|  | probe_kernel_address(ip, c)) { | 
|  | printk(" Bad EIP value."); | 
|  | break; | 
|  | } | 
|  | if (ip == (u8 *)regs->ip) | 
|  | printk("<%02x> ", c); | 
|  | else | 
|  | printk("%02x ", c); | 
|  | } | 
|  | } | 
|  | printk("\n"); | 
|  | } | 
|  |  | 
|  | int is_valid_bugaddr(unsigned long ip) | 
|  | { | 
|  | unsigned short ud2; | 
|  |  | 
|  | if (ip < PAGE_OFFSET) | 
|  | return 0; | 
|  | if (probe_kernel_address((unsigned short *)ip, ud2)) | 
|  | return 0; | 
|  |  | 
|  | return ud2 == 0x0b0f; | 
|  | } | 
|  |  | 
|  | static raw_spinlock_t die_lock = __RAW_SPIN_LOCK_UNLOCKED; | 
|  | static int die_owner = -1; | 
|  | static unsigned int die_nest_count; | 
|  |  | 
|  | unsigned __kprobes long oops_begin(void) | 
|  | { | 
|  | unsigned long flags; | 
|  |  | 
|  | oops_enter(); | 
|  |  | 
|  | if (die_owner != raw_smp_processor_id()) { | 
|  | console_verbose(); | 
|  | raw_local_irq_save(flags); | 
|  | __raw_spin_lock(&die_lock); | 
|  | die_owner = smp_processor_id(); | 
|  | die_nest_count = 0; | 
|  | bust_spinlocks(1); | 
|  | } else { | 
|  | raw_local_irq_save(flags); | 
|  | } | 
|  | die_nest_count++; | 
|  | return flags; | 
|  | } | 
|  |  | 
|  | void __kprobes oops_end(unsigned long flags, struct pt_regs *regs, int signr) | 
|  | { | 
|  | bust_spinlocks(0); | 
|  | die_owner = -1; | 
|  | add_taint(TAINT_DIE); | 
|  | __raw_spin_unlock(&die_lock); | 
|  | raw_local_irq_restore(flags); | 
|  |  | 
|  | if (!regs) | 
|  | return; | 
|  |  | 
|  | if (kexec_should_crash(current)) | 
|  | crash_kexec(regs); | 
|  | if (in_interrupt()) | 
|  | panic("Fatal exception in interrupt"); | 
|  | if (panic_on_oops) | 
|  | panic("Fatal exception"); | 
|  | oops_exit(); | 
|  | do_exit(signr); | 
|  | } | 
|  |  | 
|  | int __kprobes __die(const char *str, struct pt_regs *regs, long err) | 
|  | { | 
|  | unsigned short ss; | 
|  | unsigned long sp; | 
|  |  | 
|  | printk(KERN_EMERG "%s: %04lx [#%d] ", str, err & 0xffff, ++die_counter); | 
|  | #ifdef CONFIG_PREEMPT | 
|  | printk("PREEMPT "); | 
|  | #endif | 
|  | #ifdef CONFIG_SMP | 
|  | printk("SMP "); | 
|  | #endif | 
|  | #ifdef CONFIG_DEBUG_PAGEALLOC | 
|  | printk("DEBUG_PAGEALLOC"); | 
|  | #endif | 
|  | printk("\n"); | 
|  | sysfs_printk_last_file(); | 
|  | if (notify_die(DIE_OOPS, str, regs, err, | 
|  | current->thread.trap_no, SIGSEGV) == NOTIFY_STOP) | 
|  | return 1; | 
|  |  | 
|  | show_registers(regs); | 
|  | /* Executive summary in case the oops scrolled away */ | 
|  | sp = (unsigned long) (®s->sp); | 
|  | savesegment(ss, ss); | 
|  | if (user_mode(regs)) { | 
|  | sp = regs->sp; | 
|  | ss = regs->ss & 0xffff; | 
|  | } | 
|  | printk(KERN_EMERG "EIP: [<%08lx>] ", regs->ip); | 
|  | print_symbol("%s", regs->ip); | 
|  | printk(" SS:ESP %04x:%08lx\n", ss, sp); | 
|  | return 0; | 
|  | } | 
|  |  | 
|  | /* | 
|  | * This is gone through when something in the kernel has done something bad | 
|  | * and is about to be terminated: | 
|  | */ | 
|  | void die(const char *str, struct pt_regs *regs, long err) | 
|  | { | 
|  | unsigned long flags = oops_begin(); | 
|  |  | 
|  | if (die_nest_count < 3) { | 
|  | report_bug(regs->ip, regs); | 
|  |  | 
|  | if (__die(str, regs, err)) | 
|  | regs = NULL; | 
|  | } else { | 
|  | printk(KERN_EMERG "Recursive die() failure, output suppressed\n"); | 
|  | } | 
|  |  | 
|  | oops_end(flags, regs, SIGSEGV); | 
|  | } | 
|  |  | 
|  | static DEFINE_SPINLOCK(nmi_print_lock); | 
|  |  | 
|  | void notrace __kprobes | 
|  | die_nmi(char *str, struct pt_regs *regs, int do_panic) | 
|  | { | 
|  | if (notify_die(DIE_NMIWATCHDOG, str, regs, 0, 2, SIGINT) == NOTIFY_STOP) | 
|  | return; | 
|  |  | 
|  | spin_lock(&nmi_print_lock); | 
|  | /* | 
|  | * We are in trouble anyway, lets at least try | 
|  | * to get a message out: | 
|  | */ | 
|  | bust_spinlocks(1); | 
|  | printk(KERN_EMERG "%s", str); | 
|  | printk(" on CPU%d, ip %08lx, registers:\n", | 
|  | smp_processor_id(), regs->ip); | 
|  | show_registers(regs); | 
|  | if (do_panic) | 
|  | panic("Non maskable interrupt"); | 
|  | console_silent(); | 
|  | spin_unlock(&nmi_print_lock); | 
|  |  | 
|  | /* | 
|  | * If we are in kernel we are probably nested up pretty bad | 
|  | * and might aswell get out now while we still can: | 
|  | */ | 
|  | if (!user_mode_vm(regs)) { | 
|  | current->thread.trap_no = 2; | 
|  | crash_kexec(regs); | 
|  | } | 
|  |  | 
|  | bust_spinlocks(0); | 
|  | do_exit(SIGSEGV); | 
|  | } | 
|  |  | 
|  | static int __init oops_setup(char *s) | 
|  | { | 
|  | if (!s) | 
|  | return -EINVAL; | 
|  | if (!strcmp(s, "panic")) | 
|  | panic_on_oops = 1; | 
|  | return 0; | 
|  | } | 
|  | early_param("oops", oops_setup); | 
|  |  | 
|  | static int __init kstack_setup(char *s) | 
|  | { | 
|  | if (!s) | 
|  | return -EINVAL; | 
|  | kstack_depth_to_print = simple_strtoul(s, NULL, 0); | 
|  | return 0; | 
|  | } | 
|  | early_param("kstack", kstack_setup); | 
|  |  | 
|  | static int __init code_bytes_setup(char *s) | 
|  | { | 
|  | code_bytes = simple_strtoul(s, NULL, 0); | 
|  | if (code_bytes > 8192) | 
|  | code_bytes = 8192; | 
|  |  | 
|  | return 1; | 
|  | } | 
|  | __setup("code_bytes=", code_bytes_setup); |