X-Git-Url: http://ftp.safe.ca/?p=safe%2Fjmp%2Flinux-2.6;a=blobdiff_plain;f=kernel%2Fpanic.c;h=5827f7b972542f10d9accb69e218af4f7b105c91;hp=50cf9257b2341baa5e6a66e5634b47eaa993324e;hb=d5aa407f59f5b83d2c50ec88f5bf56d40f1f8978;hpb=54371a43a66f4477889769b4fa00df936855dc8f diff --git a/kernel/panic.c b/kernel/panic.c index 50cf925..5827f7b 100644 --- a/kernel/panic.c +++ b/kernel/panic.c @@ -8,22 +8,24 @@ * This function is used through-out the kernel (including mm and fs) * to indicate a major problem. */ +#include +#include +#include +#include +#include #include -#include -#include +#include #include -#include -#include +#include +#include +#include #include -#include +#include #include -#include -#include -#include -#include +#include int panic_on_oops; -int tainted; +static unsigned long tainted_mask; static int pause_on_oops; static int pause_on_oops_flag; static DEFINE_SPINLOCK(pause_on_oops_lock); @@ -34,13 +36,6 @@ ATOMIC_NOTIFIER_HEAD(panic_notifier_list); EXPORT_SYMBOL(panic_notifier_list); -static int __init panic_setup(char *str) -{ - panic_timeout = simple_strtoul(str, NULL, 0); - return 1; -} -__setup("panic=", panic_setup); - static long no_blink(long time) { return 0; @@ -58,19 +53,15 @@ EXPORT_SYMBOL(panic_blink); * * This function never returns. */ - NORET_TYPE void panic(const char * fmt, ...) { - long i; static char buf[1024]; va_list args; -#if defined(CONFIG_S390) - unsigned long caller = (unsigned long) __builtin_return_address(0); -#endif + long i; /* - * It's possible to come here directly from a panic-assertion and not - * have preempt disabled. Some functions called from here want + * It's possible to come here directly from a panic-assertion and + * not have preempt disabled. Some functions called from here want * preempt to be disabled. No point enabling it later though... */ preempt_disable(); @@ -83,8 +74,8 @@ NORET_TYPE void panic(const char * fmt, ...) #ifdef CONFIG_DEBUG_BUGVERBOSE dump_stack(); #endif - bust_spinlocks(0); + kmsg_dump(KMSG_DUMP_PANIC); /* * If we have crashed and we have a crash kernel loaded let it handle * everything else. @@ -92,35 +83,37 @@ NORET_TYPE void panic(const char * fmt, ...) */ crash_kexec(NULL); -#ifdef CONFIG_SMP /* * Note smp_send_stop is the usual smp shutdown function, which * unfortunately means it may not be hardened to work in a panic * situation. */ smp_send_stop(); -#endif atomic_notifier_call_chain(&panic_notifier_list, 0, buf); + bust_spinlocks(0); + if (!panic_blink) panic_blink = no_blink; if (panic_timeout > 0) { /* - * Delay timeout seconds before rebooting the machine. - * We can't use the "normal" timers since we just panicked.. - */ - printk(KERN_EMERG "Rebooting in %d seconds..",panic_timeout); + * Delay timeout seconds before rebooting the machine. + * We can't use the "normal" timers since we just panicked. + */ + printk(KERN_EMERG "Rebooting in %d seconds..", panic_timeout); + for (i = 0; i < panic_timeout*1000; ) { touch_nmi_watchdog(); i += panic_blink(i); mdelay(1); i++; } - /* This will not be a clean reboot, with everything - * shutting down. But if there is a chance of - * rebooting the system it will be rebooted. + /* + * This will not be a clean reboot, with everything + * shutting down. But if there is a chance of + * rebooting the system it will be rebooted. */ emergency_restart(); } @@ -133,10 +126,15 @@ NORET_TYPE void panic(const char * fmt, ...) } #endif #if defined(CONFIG_S390) - disabled_wait(caller); + { + unsigned long caller; + + caller = (unsigned long)__builtin_return_address(0); + disabled_wait(caller); + } #endif local_irq_enable(); - for (i = 0;;) { + for (i = 0; ; ) { touch_softlockup_watchdog(); i += panic_blink(i); mdelay(1); @@ -146,6 +144,27 @@ NORET_TYPE void panic(const char * fmt, ...) EXPORT_SYMBOL(panic); + +struct tnt { + u8 bit; + char true; + char false; +}; + +static const struct tnt tnts[] = { + { TAINT_PROPRIETARY_MODULE, 'P', 'G' }, + { TAINT_FORCED_MODULE, 'F', ' ' }, + { TAINT_UNSAFE_SMP, 'S', ' ' }, + { TAINT_FORCED_RMMOD, 'R', ' ' }, + { TAINT_MACHINE_CHECK, 'M', ' ' }, + { TAINT_BAD_PAGE, 'B', ' ' }, + { TAINT_USER, 'U', ' ' }, + { TAINT_DIE, 'D', ' ' }, + { TAINT_OVERRIDDEN_ACPI_TABLE, 'A', ' ' }, + { TAINT_WARN, 'W', ' ' }, + { TAINT_CRAP, 'C', ' ' }, +}; + /** * print_tainted - return a string to represent the kernel taint state. * @@ -156,46 +175,60 @@ EXPORT_SYMBOL(panic); * 'M' - System experienced a machine check exception. * 'B' - System has hit bad_page. * 'U' - Userspace-defined naughtiness. + * 'D' - Kernel has oopsed before * 'A' - ACPI table overridden. * 'W' - Taint on warning. + * 'C' - modules from drivers/staging are loaded. * - * The string is overwritten by the next call to print_taint(). + * The string is overwritten by the next call to print_tainted(). */ - const char *print_tainted(void) { - static char buf[20]; - if (tainted) { - snprintf(buf, sizeof(buf), "Tainted: %c%c%c%c%c%c%c%c%c%c", - tainted & TAINT_PROPRIETARY_MODULE ? 'P' : 'G', - tainted & TAINT_FORCED_MODULE ? 'F' : ' ', - tainted & TAINT_UNSAFE_SMP ? 'S' : ' ', - tainted & TAINT_FORCED_RMMOD ? 'R' : ' ', - tainted & TAINT_MACHINE_CHECK ? 'M' : ' ', - tainted & TAINT_BAD_PAGE ? 'B' : ' ', - tainted & TAINT_USER ? 'U' : ' ', - tainted & TAINT_DIE ? 'D' : ' ', - tainted & TAINT_OVERRIDDEN_ACPI_TABLE ? 'A' : ' ', - tainted & TAINT_WARN ? 'W' : ' '); - } - else + static char buf[ARRAY_SIZE(tnts) + sizeof("Tainted: ") + 1]; + + if (tainted_mask) { + char *s; + int i; + + s = buf + sprintf(buf, "Tainted: "); + for (i = 0; i < ARRAY_SIZE(tnts); i++) { + const struct tnt *t = &tnts[i]; + *s++ = test_bit(t->bit, &tainted_mask) ? + t->true : t->false; + } + *s = 0; + } else snprintf(buf, sizeof(buf), "Not tainted"); - return(buf); + + return buf; } -void add_taint(unsigned flag) +int test_taint(unsigned flag) { - debug_locks = 0; /* can't trust the integrity of the kernel anymore */ - tainted |= flag; + return test_bit(flag, &tainted_mask); } -EXPORT_SYMBOL(add_taint); +EXPORT_SYMBOL(test_taint); -static int __init pause_on_oops_setup(char *str) +unsigned long get_taint(void) { - pause_on_oops = simple_strtoul(str, NULL, 0); - return 1; + return tainted_mask; +} + +void add_taint(unsigned flag) +{ + /* + * Can't trust the integrity of the kernel anymore. + * We don't call directly debug_locks_off() because the issue + * is not necessarily serious enough to set oops_in_progress to 1 + * Also we want to keep up lockdep for staging development and + * post-warning case. + */ + if (flag != TAINT_CRAP && flag != TAINT_WARN && __debug_locks_off()) + printk(KERN_WARNING "Disabling lock debugging due to kernel taint\n"); + + set_bit(flag, &tainted_mask); } -__setup("pause_on_oops=", pause_on_oops_setup); +EXPORT_SYMBOL(add_taint); static void spin_msec(int msecs) { @@ -247,8 +280,8 @@ static void do_oops_enter_exit(void) } /* - * Return true if the calling CPU is allowed to print oops-related info. This - * is a bit racy.. + * Return true if the calling CPU is allowed to print oops-related info. + * This is a bit racy.. */ int oops_may_print(void) { @@ -257,20 +290,23 @@ int oops_may_print(void) /* * Called when the architecture enters its oops handler, before it prints - * anything. If this is the first CPU to oops, and it's oopsing the first time - * then let it proceed. + * anything. If this is the first CPU to oops, and it's oopsing the first + * time then let it proceed. * - * This is all enabled by the pause_on_oops kernel boot option. We do all this - * to ensure that oopses don't scroll off the screen. It has the side-effect - * of preventing later-oopsing CPUs from mucking up the display, too. + * This is all enabled by the pause_on_oops kernel boot option. We do all + * this to ensure that oopses don't scroll off the screen. It has the + * side-effect of preventing later-oopsing CPUs from mucking up the display, + * too. * - * It turns out that the CPU which is allowed to print ends up pausing for the - * right duration, whereas all the other CPUs pause for twice as long: once in - * oops_enter(), once in oops_exit(). + * It turns out that the CPU which is allowed to print ends up pausing for + * the right duration, whereas all the other CPUs pause for twice as long: + * once in oops_enter(), once in oops_exit(). */ void oops_enter(void) { - debug_locks_off(); /* can't trust the integrity of the kernel anymore */ + tracing_off(); + /* can't trust the integrity of the kernel anymore: */ + debug_locks_off(); do_oops_enter_exit(); } @@ -283,6 +319,8 @@ static int init_oops_id(void) { if (!oops_id) get_random_bytes(&oops_id, sizeof(oops_id)); + else + oops_id++; return 0; } @@ -303,103 +341,66 @@ void oops_exit(void) { do_oops_enter_exit(); print_oops_end_marker(); + kmsg_dump(KMSG_DUMP_OOPS); } #ifdef WANT_WARN_ON_SLOWPATH -void warn_on_slowpath(const char *file, int line) +struct slowpath_args { + const char *fmt; + va_list args; +}; + +static void warn_slowpath_common(const char *file, int line, void *caller, struct slowpath_args *args) { - char function[KSYM_SYMBOL_LEN]; - unsigned long caller = (unsigned long) __builtin_return_address(0); - sprint_symbol(function, caller); + const char *board; printk(KERN_WARNING "------------[ cut here ]------------\n"); - printk(KERN_WARNING "WARNING: at %s:%d %s()\n", file, - line, function); + printk(KERN_WARNING "WARNING: at %s:%d %pS()\n", file, line, caller); + board = dmi_get_system_info(DMI_PRODUCT_NAME); + if (board) + printk(KERN_WARNING "Hardware name: %s\n", board); + + if (args) + vprintk(args->fmt, args->args); + print_modules(); dump_stack(); print_oops_end_marker(); add_taint(TAINT_WARN); } -EXPORT_SYMBOL(warn_on_slowpath); -#endif - -#ifdef CONFIG_CC_STACKPROTECTOR -static unsigned long __stack_check_testing; -/* - * Self test function for the stack-protector feature. - * This test requires that the local variable absolutely has - * a stack slot, hence the barrier()s. - */ -static noinline void __stack_chk_test_func(void) +void warn_slowpath_fmt(const char *file, int line, const char *fmt, ...) { - unsigned long foo; - barrier(); - /* - * we need to make sure we're not about to clobber the return address, - * while real exploits do this, it's unhealthy on a running system. - * Besides, if we would, the test is already failed anyway so - * time to pull the emergency brake on it. - */ - if ((unsigned long)__builtin_return_address(0) == - *(((unsigned long *)&foo)+1)) { - printk(KERN_ERR "No -fstack-protector-stack-frame!\n"); - return; - } -#ifdef CONFIG_FRAME_POINTER - /* We also don't want to clobber the frame pointer */ - if ((unsigned long)__builtin_return_address(0) == - *(((unsigned long *)&foo)+2)) { - printk(KERN_ERR "No -fstack-protector-stack-frame!\n"); - return; - } -#endif - barrier(); - if (current->stack_canary == *(((unsigned long *)&foo)+1)) - *(((unsigned long *)&foo)+1) = 0; - else - printk(KERN_ERR "No -fstack-protector canary found\n"); - barrier(); + struct slowpath_args args; + + args.fmt = fmt; + va_start(args.args, fmt); + warn_slowpath_common(file, line, __builtin_return_address(0), &args); + va_end(args.args); } +EXPORT_SYMBOL(warn_slowpath_fmt); -static int __stack_chk_test(void) +void warn_slowpath_null(const char *file, int line) { - printk(KERN_INFO "Testing -fstack-protector-all feature\n"); - __stack_check_testing = (unsigned long)&__stack_chk_test_func; - __stack_chk_test_func(); - if (__stack_check_testing) { - printk(KERN_ERR "-fstack-protector-all test failed\n"); - WARN_ON(1); - } - return 0; + warn_slowpath_common(file, line, __builtin_return_address(0), NULL); } +EXPORT_SYMBOL(warn_slowpath_null); +#endif + +#ifdef CONFIG_CC_STACKPROTECTOR + /* * Called when gcc's -fstack-protector feature is used, and * gcc detects corruption of the on-stack canary value */ void __stack_chk_fail(void) { - if (__stack_check_testing == (unsigned long)&__stack_chk_test_func) { - long delta; - - delta = (unsigned long)__builtin_return_address(0) - - __stack_check_testing; - /* - * The test needs to happen inside the test function, so - * check if the return address is close to that function. - * The function is only 2 dozen bytes long, but keep a wide - * safety margin to avoid panic()s for normal users regardless - * of the quality of the compiler. - */ - if (delta >= 0 && delta <= 400) { - __stack_check_testing = 0; - return; - } - } panic("stack-protector: Kernel stack is corrupted in: %p\n", __builtin_return_address(0)); } EXPORT_SYMBOL(__stack_chk_fail); -late_initcall(__stack_chk_test); #endif + +core_param(panic, panic_timeout, int, 0644); +core_param(pause_on_oops, pause_on_oops, int, 0644);