/* * Linux Kernel Dump Test Module for testing kernel crashes conditions: * induces system failures at predefined crashpoints and under predefined * operational conditions in order to evaluate the reliability of kernel * sanity checking and crash dumps obtained using different dumping * solutions. * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2 of the License, or * (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. * * Copyright (C) IBM Corporation, 2006 * * Author: Ankita Garg * * It is adapted from the Linux Kernel Dump Test Tool by * Fernando Luis Vazquez Cao * * Debugfs support added by Simon Kagstrom * * See Documentation/fault-injection/provoke-crashes.txt for instructions */ #define pr_fmt(fmt) "lkdtm: " fmt #include #include #include #include #include #include #include #include #include #include #include #include #ifdef CONFIG_IDE #include #endif #include "lkdtm.h" #define DEFAULT_COUNT 10 static int lkdtm_parse_commandline(void); static void lkdtm_handler(void); enum cname { CN_INVALID, CN_INT_HARDWARE_ENTRY, CN_INT_HW_IRQ_EN, CN_INT_TASKLET_ENTRY, CN_FS_DEVRW, CN_MEM_SWAPOUT, CN_TIMERADD, CN_SCSI_DISPATCH_CMD, CN_IDE_CORE_CP, CN_DIRECT, }; enum ctype { CT_NONE, CT_PANIC, CT_BUG, CT_WARNING, CT_EXCEPTION, CT_LOOP, CT_OVERFLOW, CT_CORRUPT_STACK, CT_UNALIGNED_LOAD_STORE_WRITE, CT_OVERWRITE_ALLOCATION, CT_WRITE_AFTER_FREE, CT_READ_AFTER_FREE, CT_WRITE_BUDDY_AFTER_FREE, CT_READ_BUDDY_AFTER_FREE, CT_SOFTLOCKUP, CT_HARDLOCKUP, CT_SPINLOCKUP, CT_HUNG_TASK, CT_EXEC_DATA, CT_EXEC_STACK, CT_EXEC_KMALLOC, CT_EXEC_VMALLOC, CT_EXEC_RODATA, CT_EXEC_USERSPACE, CT_ACCESS_USERSPACE, CT_WRITE_RO, CT_WRITE_RO_AFTER_INIT, CT_WRITE_KERN, CT_ATOMIC_UNDERFLOW, CT_ATOMIC_OVERFLOW, CT_USERCOPY_HEAP_SIZE_TO, CT_USERCOPY_HEAP_SIZE_FROM, CT_USERCOPY_HEAP_FLAG_TO, CT_USERCOPY_HEAP_FLAG_FROM, CT_USERCOPY_STACK_FRAME_TO, CT_USERCOPY_STACK_FRAME_FROM, CT_USERCOPY_STACK_BEYOND, CT_USERCOPY_KERNEL, }; static char* cp_name[] = { "INVALID", "INT_HARDWARE_ENTRY", "INT_HW_IRQ_EN", "INT_TASKLET_ENTRY", "FS_DEVRW", "MEM_SWAPOUT", "TIMERADD", "SCSI_DISPATCH_CMD", "IDE_CORE_CP", "DIRECT", }; static char* cp_type[] = { "NONE", "PANIC", "BUG", "WARNING", "EXCEPTION", "LOOP", "OVERFLOW", "CORRUPT_STACK", "UNALIGNED_LOAD_STORE_WRITE", "OVERWRITE_ALLOCATION", "WRITE_AFTER_FREE", "READ_AFTER_FREE", "WRITE_BUDDY_AFTER_FREE", "READ_BUDDY_AFTER_FREE", "SOFTLOCKUP", "HARDLOCKUP", "SPINLOCKUP", "HUNG_TASK", "EXEC_DATA", "EXEC_STACK", "EXEC_KMALLOC", "EXEC_VMALLOC", "EXEC_RODATA", "EXEC_USERSPACE", "ACCESS_USERSPACE", "WRITE_RO", "WRITE_RO_AFTER_INIT", "WRITE_KERN", "ATOMIC_UNDERFLOW", "ATOMIC_OVERFLOW", "USERCOPY_HEAP_SIZE_TO", "USERCOPY_HEAP_SIZE_FROM", "USERCOPY_HEAP_FLAG_TO", "USERCOPY_HEAP_FLAG_FROM", "USERCOPY_STACK_FRAME_TO", "USERCOPY_STACK_FRAME_FROM", "USERCOPY_STACK_BEYOND", "USERCOPY_KERNEL", }; /* Global jprobe entry and crashtype. */ static struct jprobe lkdtm_jprobe; static enum cname lkdtm_crashpoint = CN_INVALID; static enum ctype lkdtm_crashtype = CT_NONE; /* Global crash counter and spinlock. */ static int crash_count = DEFAULT_COUNT; static DEFINE_SPINLOCK(crash_count_lock); /* Module parameters */ static int recur_count = -1; module_param(recur_count, int, 0644); MODULE_PARM_DESC(recur_count, " Recursion level for the stack overflow test"); static char* cpoint_name; module_param(cpoint_name, charp, 0444); MODULE_PARM_DESC(cpoint_name, " Crash Point, where kernel is to be crashed"); static char* cpoint_type; module_param(cpoint_type, charp, 0444); MODULE_PARM_DESC(cpoint_type, " Crash Point Type, action to be taken on "\ "hitting the crash point"); static int cpoint_count = DEFAULT_COUNT; module_param(cpoint_count, int, 0644); MODULE_PARM_DESC(cpoint_count, " Crash Point Count, number of times the "\ "crash point is to be hit to trigger action"); static unsigned int jp_do_irq(unsigned int irq) { lkdtm_handler(); jprobe_return(); return 0; } static irqreturn_t jp_handle_irq_event(unsigned int irq, struct irqaction *action) { lkdtm_handler(); jprobe_return(); return 0; } static void jp_tasklet_action(struct softirq_action *a) { lkdtm_handler(); jprobe_return(); } static void jp_ll_rw_block(int rw, int nr, struct buffer_head *bhs[]) { lkdtm_handler(); jprobe_return(); } struct scan_control; static unsigned long jp_shrink_inactive_list(unsigned long max_scan, struct zone *zone, struct scan_control *sc) { lkdtm_handler(); jprobe_return(); return 0; } static int jp_hrtimer_start(struct hrtimer *timer, ktime_t tim, const enum hrtimer_mode mode) { lkdtm_handler(); jprobe_return(); return 0; } static int jp_scsi_dispatch_cmd(struct scsi_cmnd *cmd) { lkdtm_handler(); jprobe_return(); return 0; } #ifdef CONFIG_IDE static int jp_generic_ide_ioctl(ide_drive_t *drive, struct file *file, struct block_device *bdev, unsigned int cmd, unsigned long arg) { lkdtm_handler(); jprobe_return(); return 0; } #endif /* Return the crashpoint number or NONE if the name is invalid */ static enum ctype parse_cp_type(const char *what, size_t count) { int i; for (i = 0; i < ARRAY_SIZE(cp_type); i++) { if (!strcmp(what, cp_type[i])) return i; } return CT_NONE; } static const char *cp_type_to_str(enum ctype type) { if (type == CT_NONE || type < 0 || type > ARRAY_SIZE(cp_type)) return "NONE"; return cp_type[type]; } static const char *cp_name_to_str(enum cname name) { if (name == CN_INVALID || name < 0 || name > ARRAY_SIZE(cp_name)) return "INVALID"; return cp_name[name]; } static int lkdtm_parse_commandline(void) { int i; unsigned long flags; if (cpoint_count < 1 || recur_count < 1) return -EINVAL; spin_lock_irqsave(&crash_count_lock, flags); crash_count = cpoint_count; spin_unlock_irqrestore(&crash_count_lock, flags); /* No special parameters */ if (!cpoint_type && !cpoint_name) return 0; /* Neither or both of these need to be set */ if (!cpoint_type || !cpoint_name) return -EINVAL; lkdtm_crashtype = parse_cp_type(cpoint_type, strlen(cpoint_type)); if (lkdtm_crashtype == CT_NONE) return -EINVAL; /* Refuse INVALID as a selectable crashpoint name. */ if (!strcmp(cpoint_name, "INVALID")) return -EINVAL; for (i = 0; i < ARRAY_SIZE(cp_name); i++) { if (!strcmp(cpoint_name, cp_name[i])) { lkdtm_crashpoint = i; return 0; } } /* Could not find a valid crash point */ return -EINVAL; } static void lkdtm_do_action(enum ctype which) { switch (which) { case CT_PANIC: lkdtm_PANIC(); break; case CT_BUG: lkdtm_BUG(); break; case CT_WARNING: lkdtm_WARNING(); break; case CT_EXCEPTION: lkdtm_EXCEPTION(); break; case CT_LOOP: lkdtm_LOOP(); break; case CT_OVERFLOW: lkdtm_OVERFLOW(); break; case CT_CORRUPT_STACK: lkdtm_CORRUPT_STACK(); break; case CT_UNALIGNED_LOAD_STORE_WRITE: lkdtm_UNALIGNED_LOAD_STORE_WRITE(); break; case CT_OVERWRITE_ALLOCATION: lkdtm_OVERWRITE_ALLOCATION(); break; case CT_WRITE_AFTER_FREE: lkdtm_WRITE_AFTER_FREE(); break; case CT_READ_AFTER_FREE: lkdtm_READ_AFTER_FREE(); break; case CT_WRITE_BUDDY_AFTER_FREE: lkdtm_WRITE_BUDDY_AFTER_FREE(); break; case CT_READ_BUDDY_AFTER_FREE: lkdtm_READ_BUDDY_AFTER_FREE(); break; case CT_SOFTLOCKUP: lkdtm_SOFTLOCKUP(); break; case CT_HARDLOCKUP: lkdtm_HARDLOCKUP(); break; case CT_SPINLOCKUP: lkdtm_SPINLOCKUP(); break; case CT_HUNG_TASK: lkdtm_HUNG_TASK(); break; case CT_EXEC_DATA: lkdtm_EXEC_DATA(); break; case CT_EXEC_STACK: lkdtm_EXEC_STACK(); break; case CT_EXEC_KMALLOC: lkdtm_EXEC_KMALLOC(); break; case CT_EXEC_VMALLOC: lkdtm_EXEC_VMALLOC(); break; case CT_EXEC_RODATA: lkdtm_EXEC_RODATA(); break; case CT_EXEC_USERSPACE: lkdtm_EXEC_USERSPACE(); break; case CT_ACCESS_USERSPACE: lkdtm_ACCESS_USERSPACE(); break; case CT_WRITE_RO: lkdtm_WRITE_RO(); break; case CT_WRITE_RO_AFTER_INIT: lkdtm_WRITE_RO_AFTER_INIT(); break; case CT_WRITE_KERN: lkdtm_WRITE_KERN(); break; case CT_ATOMIC_UNDERFLOW: lkdtm_ATOMIC_UNDERFLOW(); break; case CT_ATOMIC_OVERFLOW: lkdtm_ATOMIC_OVERFLOW(); break; case CT_USERCOPY_HEAP_SIZE_TO: lkdtm_USERCOPY_HEAP_SIZE_TO(); break; case CT_USERCOPY_HEAP_SIZE_FROM: lkdtm_USERCOPY_HEAP_SIZE_FROM(); break; case CT_USERCOPY_HEAP_FLAG_TO: lkdtm_USERCOPY_HEAP_FLAG_TO(); break; case CT_USERCOPY_HEAP_FLAG_FROM: lkdtm_USERCOPY_HEAP_FLAG_FROM(); break; case CT_USERCOPY_STACK_FRAME_TO: lkdtm_USERCOPY_STACK_FRAME_TO(); break; case CT_USERCOPY_STACK_FRAME_FROM: lkdtm_USERCOPY_STACK_FRAME_FROM(); break; case CT_USERCOPY_STACK_BEYOND: lkdtm_USERCOPY_STACK_BEYOND(); break; case CT_USERCOPY_KERNEL: lkdtm_USERCOPY_KERNEL(); break; case CT_NONE: default: break; } } static void lkdtm_handler(void) { unsigned long flags; bool do_it = false; spin_lock_irqsave(&crash_count_lock, flags); crash_count--; pr_info("Crash point %s of type %s hit, trigger in %d rounds\n", cp_name_to_str(lkdtm_crashpoint), cp_type_to_str(lkdtm_crashtype), crash_count); if (crash_count == 0) { do_it = true; crash_count = cpoint_count; } spin_unlock_irqrestore(&crash_count_lock, flags); if (do_it) lkdtm_do_action(lkdtm_crashtype); } static int lkdtm_register_cpoint(enum cname which) { int ret; lkdtm_crashpoint = CN_INVALID; if (lkdtm_jprobe.entry != NULL) unregister_jprobe(&lkdtm_jprobe); switch (which) { case CN_DIRECT: lkdtm_do_action(lkdtm_crashtype); return 0; case CN_INT_HARDWARE_ENTRY: lkdtm_jprobe.kp.symbol_name = "do_IRQ"; lkdtm_jprobe.entry = (kprobe_opcode_t*) jp_do_irq; break; case CN_INT_HW_IRQ_EN: lkdtm_jprobe.kp.symbol_name = "handle_IRQ_event"; lkdtm_jprobe.entry = (kprobe_opcode_t*) jp_handle_irq_event; break; case CN_INT_TASKLET_ENTRY: lkdtm_jprobe.kp.symbol_name = "tasklet_action"; lkdtm_jprobe.entry = (kprobe_opcode_t*) jp_tasklet_action; break; case CN_FS_DEVRW: lkdtm_jprobe.kp.symbol_name = "ll_rw_block"; lkdtm_jprobe.entry = (kprobe_opcode_t*) jp_ll_rw_block; break; case CN_MEM_SWAPOUT: lkdtm_jprobe.kp.symbol_name = "shrink_inactive_list"; lkdtm_jprobe.entry = (kprobe_opcode_t*) jp_shrink_inactive_list; break; case CN_TIMERADD: lkdtm_jprobe.kp.symbol_name = "hrtimer_start"; lkdtm_jprobe.entry = (kprobe_opcode_t*) jp_hrtimer_start; break; case CN_SCSI_DISPATCH_CMD: lkdtm_jprobe.kp.symbol_name = "scsi_dispatch_cmd"; lkdtm_jprobe.entry = (kprobe_opcode_t*) jp_scsi_dispatch_cmd; break; case CN_IDE_CORE_CP: #ifdef CONFIG_IDE lkdtm_jprobe.kp.symbol_name = "generic_ide_ioctl"; lkdtm_jprobe.entry = (kprobe_opcode_t*) jp_generic_ide_ioctl; #else pr_info("Crash point not available\n"); return -EINVAL; #endif break; default: pr_info("Invalid Crash Point\n"); return -EINVAL; } lkdtm_crashpoint = which; if ((ret = register_jprobe(&lkdtm_jprobe)) < 0) { pr_info("Couldn't register jprobe\n"); lkdtm_crashpoint = CN_INVALID; } return ret; } static ssize_t do_register_entry(enum cname which, struct file *f, const char __user *user_buf, size_t count, loff_t *off) { char *buf; int err; if (count >= PAGE_SIZE) return -EINVAL; buf = (char *)__get_free_page(GFP_KERNEL); if (!buf) return -ENOMEM; if (copy_from_user(buf, user_buf, count)) { free_page((unsigned long) buf); return -EFAULT; } /* NULL-terminate and remove enter */ buf[count] = '\0'; strim(buf); lkdtm_crashtype = parse_cp_type(buf, count); free_page((unsigned long) buf); if (lkdtm_crashtype == CT_NONE) return -EINVAL; err = lkdtm_register_cpoint(which); if (err < 0) return err; *off += count; return count; } /* Generic read callback that just prints out the available crash types */ static ssize_t lkdtm_debugfs_read(struct file *f, char __user *user_buf, size_t count, loff_t *off) { char *buf; int i, n, out; buf = (char *)__get_free_page(GFP_KERNEL); if (buf == NULL) return -ENOMEM; n = snprintf(buf, PAGE_SIZE, "Available crash types:\n"); for (i = 0; i < ARRAY_SIZE(cp_type); i++) n += snprintf(buf + n, PAGE_SIZE - n, "%s\n", cp_type[i]); buf[n] = '\0'; out = simple_read_from_buffer(user_buf, count, off, buf, n); free_page((unsigned long) buf); return out; } static int lkdtm_debugfs_open(struct inode *inode, struct file *file) { return 0; } static ssize_t int_hardware_entry(struct file *f, const char __user *buf, size_t count, loff_t *off) { return do_register_entry(CN_INT_HARDWARE_ENTRY, f, buf, count, off); } static ssize_t int_hw_irq_en(struct file *f, const char __user *buf, size_t count, loff_t *off) { return do_register_entry(CN_INT_HW_IRQ_EN, f, buf, count, off); } static ssize_t int_tasklet_entry(struct file *f, const char __user *buf, size_t count, loff_t *off) { return do_register_entry(CN_INT_TASKLET_ENTRY, f, buf, count, off); } static ssize_t fs_devrw_entry(struct file *f, const char __user *buf, size_t count, loff_t *off) { return do_register_entry(CN_FS_DEVRW, f, buf, count, off); } static ssize_t mem_swapout_entry(struct file *f, const char __user *buf, size_t count, loff_t *off) { return do_register_entry(CN_MEM_SWAPOUT, f, buf, count, off); } static ssize_t timeradd_entry(struct file *f, const char __user *buf, size_t count, loff_t *off) { return do_register_entry(CN_TIMERADD, f, buf, count, off); } static ssize_t scsi_dispatch_cmd_entry(struct file *f, const char __user *buf, size_t count, loff_t *off) { return do_register_entry(CN_SCSI_DISPATCH_CMD, f, buf, count, off); } static ssize_t ide_core_cp_entry(struct file *f, const char __user *buf, size_t count, loff_t *off) { return do_register_entry(CN_IDE_CORE_CP, f, buf, count, off); } /* Special entry to just crash directly. Available without KPROBEs */ static ssize_t direct_entry(struct file *f, const char __user *user_buf, size_t count, loff_t *off) { enum ctype type; char *buf; if (count >= PAGE_SIZE) return -EINVAL; if (count < 1) return -EINVAL; buf = (char *)__get_free_page(GFP_KERNEL); if (!buf) return -ENOMEM; if (copy_from_user(buf, user_buf, count)) { free_page((unsigned long) buf); return -EFAULT; } /* NULL-terminate and remove enter */ buf[count] = '\0'; strim(buf); type = parse_cp_type(buf, count); free_page((unsigned long) buf); if (type == CT_NONE) return -EINVAL; pr_info("Performing direct entry %s\n", cp_type_to_str(type)); lkdtm_do_action(type); *off += count; return count; } struct crash_entry { const char *name; const struct file_operations fops; }; static const struct crash_entry crash_entries[] = { {"DIRECT", {.read = lkdtm_debugfs_read, .llseek = generic_file_llseek, .open = lkdtm_debugfs_open, .write = direct_entry} }, {"INT_HARDWARE_ENTRY", {.read = lkdtm_debugfs_read, .llseek = generic_file_llseek, .open = lkdtm_debugfs_open, .write = int_hardware_entry} }, {"INT_HW_IRQ_EN", {.read = lkdtm_debugfs_read, .llseek = generic_file_llseek, .open = lkdtm_debugfs_open, .write = int_hw_irq_en} }, {"INT_TASKLET_ENTRY", {.read = lkdtm_debugfs_read, .llseek = generic_file_llseek, .open = lkdtm_debugfs_open, .write = int_tasklet_entry} }, {"FS_DEVRW", {.read = lkdtm_debugfs_read, .llseek = generic_file_llseek, .open = lkdtm_debugfs_open, .write = fs_devrw_entry} }, {"MEM_SWAPOUT", {.read = lkdtm_debugfs_read, .llseek = generic_file_llseek, .open = lkdtm_debugfs_open, .write = mem_swapout_entry} }, {"TIMERADD", {.read = lkdtm_debugfs_read, .llseek = generic_file_llseek, .open = lkdtm_debugfs_open, .write = timeradd_entry} }, {"SCSI_DISPATCH_CMD", {.read = lkdtm_debugfs_read, .llseek = generic_file_llseek, .open = lkdtm_debugfs_open, .write = scsi_dispatch_cmd_entry} }, {"IDE_CORE_CP", {.read = lkdtm_debugfs_read, .llseek = generic_file_llseek, .open = lkdtm_debugfs_open, .write = ide_core_cp_entry} }, }; static struct dentry *lkdtm_debugfs_root; static int __init lkdtm_module_init(void) { int ret = -EINVAL; int n_debugfs_entries = 1; /* Assume only the direct entry */ int i; /* Handle test-specific initialization. */ lkdtm_bugs_init(&recur_count); lkdtm_perms_init(); lkdtm_usercopy_init(); /* Register debugfs interface */ lkdtm_debugfs_root = debugfs_create_dir("provoke-crash", NULL); if (!lkdtm_debugfs_root) { pr_err("creating root dir failed\n"); return -ENODEV; } #ifdef CONFIG_KPROBES n_debugfs_entries = ARRAY_SIZE(crash_entries); #endif for (i = 0; i < n_debugfs_entries; i++) { const struct crash_entry *cur = &crash_entries[i]; struct dentry *de; de = debugfs_create_file(cur->name, 0644, lkdtm_debugfs_root, NULL, &cur->fops); if (de == NULL) { pr_err("could not create %s\n", cur->name); goto out_err; } } if (lkdtm_parse_commandline() == -EINVAL) { pr_info("Invalid command\n"); goto out_err; } if (lkdtm_crashpoint != CN_INVALID && lkdtm_crashtype != CT_NONE) { ret = lkdtm_register_cpoint(lkdtm_crashpoint); if (ret < 0) { pr_info("Invalid crash point %d\n", lkdtm_crashpoint); goto out_err; } pr_info("Crash point %s of type %s registered\n", cpoint_name, cpoint_type); } else { pr_info("No crash points registered, enable through debugfs\n"); } return 0; out_err: debugfs_remove_recursive(lkdtm_debugfs_root); return ret; } static void __exit lkdtm_module_exit(void) { debugfs_remove_recursive(lkdtm_debugfs_root); /* Handle test-specific clean-up. */ lkdtm_usercopy_exit(); unregister_jprobe(&lkdtm_jprobe); pr_info("Crash point unregistered\n"); } module_init(lkdtm_module_init); module_exit(lkdtm_module_exit); MODULE_LICENSE("GPL"); MODULE_DESCRIPTION("Kprobe module for testing crash dumps");