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Message-Id: <1465336628-18219-2-git-send-email-keescook@chromium.org>
Date: Tue, 7 Jun 2016 14:57:04 -0700
From: Kees Cook <keescook@...omium.org>
To: kernel-hardening@...ts.openwall.com
Cc: Kees Cook <keescook@...omium.org>, Arnd Bergmann <arnd@...db.de>,
Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
Andrew Morton <akpm@...ux-foundation.org>,
"David S. Miller" <davem@...emloft.net>,
Mauro Carvalho Chehab <mchehab@....samsung.com>,
Jiri Slaby <jslaby@...e.cz>,
Guenter Roeck <linux@...ck-us.net>,
linux-kernel@...r.kernel.org
Subject: [PATCH 1/5] lkdtm: split build into multiple source files
Kbuild lacks a way to do in-place objcopy or other modifications of
built targets, so in order to move functions into non-text sections
without renaming the kernel module, the build of lkdtm must be split
into separate source files. This renames lkdtm.c to lkdtm_core.c in
preparation for adding the source file for the .rodata section.
Signed-off-by: Kees Cook <keescook@...omium.org>
---
drivers/misc/Makefile | 2 +
drivers/misc/lkdtm.c | 1023 ---------------------------------------------
drivers/misc/lkdtm_core.c | 1023 +++++++++++++++++++++++++++++++++++++++++++++
3 files changed, 1025 insertions(+), 1023 deletions(-)
delete mode 100644 drivers/misc/lkdtm.c
create mode 100644 drivers/misc/lkdtm_core.c
diff --git a/drivers/misc/Makefile b/drivers/misc/Makefile
index b2fb6dbffcef..c3cb6ad8cc37 100644
--- a/drivers/misc/Makefile
+++ b/drivers/misc/Makefile
@@ -57,3 +57,5 @@ obj-$(CONFIG_ECHO) += echo/
obj-$(CONFIG_VEXPRESS_SYSCFG) += vexpress-syscfg.o
obj-$(CONFIG_CXL_BASE) += cxl/
obj-$(CONFIG_PANEL) += panel.o
+
+lkdtm-$(CONFIG_LKDTM) += lkdtm_core.o
diff --git a/drivers/misc/lkdtm.c b/drivers/misc/lkdtm.c
deleted file mode 100644
index 0a5cbbe12452..000000000000
--- a/drivers/misc/lkdtm.c
+++ /dev/null
@@ -1,1023 +0,0 @@
-/*
- * Kprobe module for testing crash dumps
- *
- * 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 <ankita@...ibm.com>
- *
- * This module induces system failures at predefined crashpoints to
- * evaluate the reliability of crash dumps obtained using different dumping
- * solutions.
- *
- * It is adapted from the Linux Kernel Dump Test Tool by
- * Fernando Luis Vazquez Cao <http://lkdtt.sourceforge.net>
- *
- * Debugfs support added by Simon Kagstrom <simon.kagstrom@...insight.net>
- *
- * See Documentation/fault-injection/provoke-crashes.txt for instructions
- */
-#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
-
-#include <linux/kernel.h>
-#include <linux/fs.h>
-#include <linux/module.h>
-#include <linux/buffer_head.h>
-#include <linux/kprobes.h>
-#include <linux/list.h>
-#include <linux/init.h>
-#include <linux/interrupt.h>
-#include <linux/hrtimer.h>
-#include <linux/slab.h>
-#include <scsi/scsi_cmnd.h>
-#include <linux/debugfs.h>
-#include <linux/vmalloc.h>
-#include <linux/mman.h>
-#include <asm/cacheflush.h>
-
-#ifdef CONFIG_IDE
-#include <linux/ide.h>
-#endif
-
-/*
- * Make sure our attempts to over run the kernel stack doesn't trigger
- * a compiler warning when CONFIG_FRAME_WARN is set. Then make sure we
- * recurse past the end of THREAD_SIZE by default.
- */
-#if defined(CONFIG_FRAME_WARN) && (CONFIG_FRAME_WARN > 0)
-#define REC_STACK_SIZE (CONFIG_FRAME_WARN / 2)
-#else
-#define REC_STACK_SIZE (THREAD_SIZE / 8)
-#endif
-#define REC_NUM_DEFAULT ((THREAD_SIZE / REC_STACK_SIZE) * 2)
-
-#define DEFAULT_COUNT 10
-#define EXEC_SIZE 64
-
-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_USERSPACE,
- CT_ACCESS_USERSPACE,
- CT_WRITE_RO,
- CT_WRITE_RO_AFTER_INIT,
- CT_WRITE_KERN,
- CT_WRAP_ATOMIC
-};
-
-static char* cp_name[] = {
- "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[] = {
- "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_USERSPACE",
- "ACCESS_USERSPACE",
- "WRITE_RO",
- "WRITE_RO_AFTER_INIT",
- "WRITE_KERN",
- "WRAP_ATOMIC"
-};
-
-static struct jprobe lkdtm;
-
-static int lkdtm_parse_commandline(void);
-static void lkdtm_handler(void);
-
-static char* cpoint_name;
-static char* cpoint_type;
-static int cpoint_count = DEFAULT_COUNT;
-static int recur_count = REC_NUM_DEFAULT;
-
-static enum cname cpoint = CN_INVALID;
-static enum ctype cptype = CT_NONE;
-static int count = DEFAULT_COUNT;
-static DEFINE_SPINLOCK(count_lock);
-static DEFINE_SPINLOCK(lock_me_up);
-
-static u8 data_area[EXEC_SIZE];
-
-static const unsigned long rodata = 0xAA55AA55;
-static unsigned long ro_after_init __ro_after_init = 0x55AA5500;
-
-module_param(recur_count, int, 0644);
-MODULE_PARM_DESC(recur_count, " Recursion level for the stack overflow test");
-module_param(cpoint_name, charp, 0444);
-MODULE_PARM_DESC(cpoint_name, " Crash Point, where kernel is to be crashed");
-module_param(cpoint_type, charp, 0444);
-MODULE_PARM_DESC(cpoint_type, " Crash Point Type, action to be taken on "\
- "hitting the crash point");
-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 + 1;
- }
-
- 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 - 1];
-}
-
-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 - 1];
-}
-
-
-static int lkdtm_parse_commandline(void)
-{
- int i;
- unsigned long flags;
-
- if (cpoint_count < 1 || recur_count < 1)
- return -EINVAL;
-
- spin_lock_irqsave(&count_lock, flags);
- count = cpoint_count;
- spin_unlock_irqrestore(&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;
-
- cptype = parse_cp_type(cpoint_type, strlen(cpoint_type));
- if (cptype == CT_NONE)
- return -EINVAL;
-
- for (i = 0; i < ARRAY_SIZE(cp_name); i++) {
- if (!strcmp(cpoint_name, cp_name[i])) {
- cpoint = i + 1;
- return 0;
- }
- }
-
- /* Could not find a valid crash point */
- return -EINVAL;
-}
-
-static int recursive_loop(int remaining)
-{
- char buf[REC_STACK_SIZE];
-
- /* Make sure compiler does not optimize this away. */
- memset(buf, (remaining & 0xff) | 0x1, REC_STACK_SIZE);
- if (!remaining)
- return 0;
- else
- return recursive_loop(remaining - 1);
-}
-
-static void do_nothing(void)
-{
- return;
-}
-
-/* Must immediately follow do_nothing for size calculuations to work out. */
-static void do_overwritten(void)
-{
- pr_info("do_overwritten wasn't overwritten!\n");
- return;
-}
-
-static noinline void corrupt_stack(void)
-{
- /* Use default char array length that triggers stack protection. */
- char data[8];
-
- memset((void *)data, 0, 64);
-}
-
-static void noinline execute_location(void *dst)
-{
- void (*func)(void) = dst;
-
- pr_info("attempting ok execution at %p\n", do_nothing);
- do_nothing();
-
- memcpy(dst, do_nothing, EXEC_SIZE);
- flush_icache_range((unsigned long)dst, (unsigned long)dst + EXEC_SIZE);
- pr_info("attempting bad execution at %p\n", func);
- func();
-}
-
-static void execute_user_location(void *dst)
-{
- /* Intentionally crossing kernel/user memory boundary. */
- void (*func)(void) = dst;
-
- pr_info("attempting ok execution at %p\n", do_nothing);
- do_nothing();
-
- if (copy_to_user((void __user *)dst, do_nothing, EXEC_SIZE))
- return;
- flush_icache_range((unsigned long)dst, (unsigned long)dst + EXEC_SIZE);
- pr_info("attempting bad execution at %p\n", func);
- func();
-}
-
-static void lkdtm_do_action(enum ctype which)
-{
- switch (which) {
- case CT_PANIC:
- panic("dumptest");
- break;
- case CT_BUG:
- BUG();
- break;
- case CT_WARNING:
- WARN_ON(1);
- break;
- case CT_EXCEPTION:
- *((int *) 0) = 0;
- break;
- case CT_LOOP:
- for (;;)
- ;
- break;
- case CT_OVERFLOW:
- (void) recursive_loop(recur_count);
- break;
- case CT_CORRUPT_STACK:
- corrupt_stack();
- break;
- case CT_UNALIGNED_LOAD_STORE_WRITE: {
- static u8 data[5] __attribute__((aligned(4))) = {1, 2,
- 3, 4, 5};
- u32 *p;
- u32 val = 0x12345678;
-
- p = (u32 *)(data + 1);
- if (*p == 0)
- val = 0x87654321;
- *p = val;
- break;
- }
- case CT_OVERWRITE_ALLOCATION: {
- size_t len = 1020;
- u32 *data = kmalloc(len, GFP_KERNEL);
-
- data[1024 / sizeof(u32)] = 0x12345678;
- kfree(data);
- break;
- }
- case CT_WRITE_AFTER_FREE: {
- int *base, *again;
- size_t len = 1024;
- /*
- * The slub allocator uses the first word to store the free
- * pointer in some configurations. Use the middle of the
- * allocation to avoid running into the freelist
- */
- size_t offset = (len / sizeof(*base)) / 2;
-
- base = kmalloc(len, GFP_KERNEL);
- pr_info("Allocated memory %p-%p\n", base, &base[offset * 2]);
- pr_info("Attempting bad write to freed memory at %p\n",
- &base[offset]);
- kfree(base);
- base[offset] = 0x0abcdef0;
- /* Attempt to notice the overwrite. */
- again = kmalloc(len, GFP_KERNEL);
- kfree(again);
- if (again != base)
- pr_info("Hmm, didn't get the same memory range.\n");
-
- break;
- }
- case CT_READ_AFTER_FREE: {
- int *base, *val, saw;
- size_t len = 1024;
- /*
- * The slub allocator uses the first word to store the free
- * pointer in some configurations. Use the middle of the
- * allocation to avoid running into the freelist
- */
- size_t offset = (len / sizeof(*base)) / 2;
-
- base = kmalloc(len, GFP_KERNEL);
- if (!base)
- break;
-
- val = kmalloc(len, GFP_KERNEL);
- if (!val) {
- kfree(base);
- break;
- }
-
- *val = 0x12345678;
- base[offset] = *val;
- pr_info("Value in memory before free: %x\n", base[offset]);
-
- kfree(base);
-
- pr_info("Attempting bad read from freed memory\n");
- saw = base[offset];
- if (saw != *val) {
- /* Good! Poisoning happened, so declare a win. */
- pr_info("Memory correctly poisoned (%x)\n", saw);
- BUG();
- }
- pr_info("Memory was not poisoned\n");
-
- kfree(val);
- break;
- }
- case CT_WRITE_BUDDY_AFTER_FREE: {
- unsigned long p = __get_free_page(GFP_KERNEL);
- if (!p)
- break;
- pr_info("Writing to the buddy page before free\n");
- memset((void *)p, 0x3, PAGE_SIZE);
- free_page(p);
- schedule();
- pr_info("Attempting bad write to the buddy page after free\n");
- memset((void *)p, 0x78, PAGE_SIZE);
- /* Attempt to notice the overwrite. */
- p = __get_free_page(GFP_KERNEL);
- free_page(p);
- schedule();
-
- break;
- }
- case CT_READ_BUDDY_AFTER_FREE: {
- unsigned long p = __get_free_page(GFP_KERNEL);
- int saw, *val;
- int *base;
-
- if (!p)
- break;
-
- val = kmalloc(1024, GFP_KERNEL);
- if (!val) {
- free_page(p);
- break;
- }
-
- base = (int *)p;
-
- *val = 0x12345678;
- base[0] = *val;
- pr_info("Value in memory before free: %x\n", base[0]);
- free_page(p);
- pr_info("Attempting to read from freed memory\n");
- saw = base[0];
- if (saw != *val) {
- /* Good! Poisoning happened, so declare a win. */
- pr_info("Memory correctly poisoned (%x)\n", saw);
- BUG();
- }
- pr_info("Buddy page was not poisoned\n");
-
- kfree(val);
- break;
- }
- case CT_SOFTLOCKUP:
- preempt_disable();
- for (;;)
- cpu_relax();
- break;
- case CT_HARDLOCKUP:
- local_irq_disable();
- for (;;)
- cpu_relax();
- break;
- case CT_SPINLOCKUP:
- /* Must be called twice to trigger. */
- spin_lock(&lock_me_up);
- /* Let sparse know we intended to exit holding the lock. */
- __release(&lock_me_up);
- break;
- case CT_HUNG_TASK:
- set_current_state(TASK_UNINTERRUPTIBLE);
- schedule();
- break;
- case CT_EXEC_DATA:
- execute_location(data_area);
- break;
- case CT_EXEC_STACK: {
- u8 stack_area[EXEC_SIZE];
- execute_location(stack_area);
- break;
- }
- case CT_EXEC_KMALLOC: {
- u32 *kmalloc_area = kmalloc(EXEC_SIZE, GFP_KERNEL);
- execute_location(kmalloc_area);
- kfree(kmalloc_area);
- break;
- }
- case CT_EXEC_VMALLOC: {
- u32 *vmalloc_area = vmalloc(EXEC_SIZE);
- execute_location(vmalloc_area);
- vfree(vmalloc_area);
- break;
- }
- case CT_EXEC_USERSPACE: {
- unsigned long user_addr;
-
- user_addr = vm_mmap(NULL, 0, PAGE_SIZE,
- PROT_READ | PROT_WRITE | PROT_EXEC,
- MAP_ANONYMOUS | MAP_PRIVATE, 0);
- if (user_addr >= TASK_SIZE) {
- pr_warn("Failed to allocate user memory\n");
- return;
- }
- execute_user_location((void *)user_addr);
- vm_munmap(user_addr, PAGE_SIZE);
- break;
- }
- case CT_ACCESS_USERSPACE: {
- unsigned long user_addr, tmp = 0;
- unsigned long *ptr;
-
- user_addr = vm_mmap(NULL, 0, PAGE_SIZE,
- PROT_READ | PROT_WRITE | PROT_EXEC,
- MAP_ANONYMOUS | MAP_PRIVATE, 0);
- if (user_addr >= TASK_SIZE) {
- pr_warn("Failed to allocate user memory\n");
- return;
- }
-
- if (copy_to_user((void __user *)user_addr, &tmp, sizeof(tmp))) {
- pr_warn("copy_to_user failed\n");
- vm_munmap(user_addr, PAGE_SIZE);
- return;
- }
-
- ptr = (unsigned long *)user_addr;
-
- pr_info("attempting bad read at %p\n", ptr);
- tmp = *ptr;
- tmp += 0xc0dec0de;
-
- pr_info("attempting bad write at %p\n", ptr);
- *ptr = tmp;
-
- vm_munmap(user_addr, PAGE_SIZE);
-
- break;
- }
- case CT_WRITE_RO: {
- /* Explicitly cast away "const" for the test. */
- unsigned long *ptr = (unsigned long *)&rodata;
-
- pr_info("attempting bad rodata write at %p\n", ptr);
- *ptr ^= 0xabcd1234;
-
- break;
- }
- case CT_WRITE_RO_AFTER_INIT: {
- unsigned long *ptr = &ro_after_init;
-
- /*
- * Verify we were written to during init. Since an Oops
- * is considered a "success", a failure is to just skip the
- * real test.
- */
- if ((*ptr & 0xAA) != 0xAA) {
- pr_info("%p was NOT written during init!?\n", ptr);
- break;
- }
-
- pr_info("attempting bad ro_after_init write at %p\n", ptr);
- *ptr ^= 0xabcd1234;
-
- break;
- }
- case CT_WRITE_KERN: {
- size_t size;
- unsigned char *ptr;
-
- size = (unsigned long)do_overwritten -
- (unsigned long)do_nothing;
- ptr = (unsigned char *)do_overwritten;
-
- pr_info("attempting bad %zu byte write at %p\n", size, ptr);
- memcpy(ptr, (unsigned char *)do_nothing, size);
- flush_icache_range((unsigned long)ptr,
- (unsigned long)(ptr + size));
-
- do_overwritten();
- break;
- }
- case CT_WRAP_ATOMIC: {
- atomic_t under = ATOMIC_INIT(INT_MIN);
- atomic_t over = ATOMIC_INIT(INT_MAX);
-
- pr_info("attempting atomic underflow\n");
- atomic_dec(&under);
- pr_info("attempting atomic overflow\n");
- atomic_inc(&over);
-
- return;
- }
- case CT_NONE:
- default:
- break;
- }
-
-}
-
-static void lkdtm_handler(void)
-{
- unsigned long flags;
- bool do_it = false;
-
- spin_lock_irqsave(&count_lock, flags);
- count--;
- pr_info("Crash point %s of type %s hit, trigger in %d rounds\n",
- cp_name_to_str(cpoint), cp_type_to_str(cptype), count);
-
- if (count == 0) {
- do_it = true;
- count = cpoint_count;
- }
- spin_unlock_irqrestore(&count_lock, flags);
-
- if (do_it)
- lkdtm_do_action(cptype);
-}
-
-static int lkdtm_register_cpoint(enum cname which)
-{
- int ret;
-
- cpoint = CN_INVALID;
- if (lkdtm.entry != NULL)
- unregister_jprobe(&lkdtm);
-
- switch (which) {
- case CN_DIRECT:
- lkdtm_do_action(cptype);
- return 0;
- case CN_INT_HARDWARE_ENTRY:
- lkdtm.kp.symbol_name = "do_IRQ";
- lkdtm.entry = (kprobe_opcode_t*) jp_do_irq;
- break;
- case CN_INT_HW_IRQ_EN:
- lkdtm.kp.symbol_name = "handle_IRQ_event";
- lkdtm.entry = (kprobe_opcode_t*) jp_handle_irq_event;
- break;
- case CN_INT_TASKLET_ENTRY:
- lkdtm.kp.symbol_name = "tasklet_action";
- lkdtm.entry = (kprobe_opcode_t*) jp_tasklet_action;
- break;
- case CN_FS_DEVRW:
- lkdtm.kp.symbol_name = "ll_rw_block";
- lkdtm.entry = (kprobe_opcode_t*) jp_ll_rw_block;
- break;
- case CN_MEM_SWAPOUT:
- lkdtm.kp.symbol_name = "shrink_inactive_list";
- lkdtm.entry = (kprobe_opcode_t*) jp_shrink_inactive_list;
- break;
- case CN_TIMERADD:
- lkdtm.kp.symbol_name = "hrtimer_start";
- lkdtm.entry = (kprobe_opcode_t*) jp_hrtimer_start;
- break;
- case CN_SCSI_DISPATCH_CMD:
- lkdtm.kp.symbol_name = "scsi_dispatch_cmd";
- lkdtm.entry = (kprobe_opcode_t*) jp_scsi_dispatch_cmd;
- break;
- case CN_IDE_CORE_CP:
-#ifdef CONFIG_IDE
- lkdtm.kp.symbol_name = "generic_ide_ioctl";
- lkdtm.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;
- }
-
- cpoint = which;
- if ((ret = register_jprobe(&lkdtm)) < 0) {
- pr_info("Couldn't register jprobe\n");
- cpoint = 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);
-
- cptype = parse_cp_type(buf, count);
- free_page((unsigned long) buf);
-
- if (cptype == 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;
-
- /* Make sure we can write to __ro_after_init values during __init */
- ro_after_init |= 0xAA;
-
- /* 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 (cpoint != CN_INVALID && cptype != CT_NONE) {
- ret = lkdtm_register_cpoint(cpoint);
- if (ret < 0) {
- pr_info("Invalid crash point %d\n", cpoint);
- 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);
-
- unregister_jprobe(&lkdtm);
- 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");
diff --git a/drivers/misc/lkdtm_core.c b/drivers/misc/lkdtm_core.c
new file mode 100644
index 000000000000..0a5cbbe12452
--- /dev/null
+++ b/drivers/misc/lkdtm_core.c
@@ -0,0 +1,1023 @@
+/*
+ * Kprobe module for testing crash dumps
+ *
+ * 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 <ankita@...ibm.com>
+ *
+ * This module induces system failures at predefined crashpoints to
+ * evaluate the reliability of crash dumps obtained using different dumping
+ * solutions.
+ *
+ * It is adapted from the Linux Kernel Dump Test Tool by
+ * Fernando Luis Vazquez Cao <http://lkdtt.sourceforge.net>
+ *
+ * Debugfs support added by Simon Kagstrom <simon.kagstrom@...insight.net>
+ *
+ * See Documentation/fault-injection/provoke-crashes.txt for instructions
+ */
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/kernel.h>
+#include <linux/fs.h>
+#include <linux/module.h>
+#include <linux/buffer_head.h>
+#include <linux/kprobes.h>
+#include <linux/list.h>
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/hrtimer.h>
+#include <linux/slab.h>
+#include <scsi/scsi_cmnd.h>
+#include <linux/debugfs.h>
+#include <linux/vmalloc.h>
+#include <linux/mman.h>
+#include <asm/cacheflush.h>
+
+#ifdef CONFIG_IDE
+#include <linux/ide.h>
+#endif
+
+/*
+ * Make sure our attempts to over run the kernel stack doesn't trigger
+ * a compiler warning when CONFIG_FRAME_WARN is set. Then make sure we
+ * recurse past the end of THREAD_SIZE by default.
+ */
+#if defined(CONFIG_FRAME_WARN) && (CONFIG_FRAME_WARN > 0)
+#define REC_STACK_SIZE (CONFIG_FRAME_WARN / 2)
+#else
+#define REC_STACK_SIZE (THREAD_SIZE / 8)
+#endif
+#define REC_NUM_DEFAULT ((THREAD_SIZE / REC_STACK_SIZE) * 2)
+
+#define DEFAULT_COUNT 10
+#define EXEC_SIZE 64
+
+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_USERSPACE,
+ CT_ACCESS_USERSPACE,
+ CT_WRITE_RO,
+ CT_WRITE_RO_AFTER_INIT,
+ CT_WRITE_KERN,
+ CT_WRAP_ATOMIC
+};
+
+static char* cp_name[] = {
+ "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[] = {
+ "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_USERSPACE",
+ "ACCESS_USERSPACE",
+ "WRITE_RO",
+ "WRITE_RO_AFTER_INIT",
+ "WRITE_KERN",
+ "WRAP_ATOMIC"
+};
+
+static struct jprobe lkdtm;
+
+static int lkdtm_parse_commandline(void);
+static void lkdtm_handler(void);
+
+static char* cpoint_name;
+static char* cpoint_type;
+static int cpoint_count = DEFAULT_COUNT;
+static int recur_count = REC_NUM_DEFAULT;
+
+static enum cname cpoint = CN_INVALID;
+static enum ctype cptype = CT_NONE;
+static int count = DEFAULT_COUNT;
+static DEFINE_SPINLOCK(count_lock);
+static DEFINE_SPINLOCK(lock_me_up);
+
+static u8 data_area[EXEC_SIZE];
+
+static const unsigned long rodata = 0xAA55AA55;
+static unsigned long ro_after_init __ro_after_init = 0x55AA5500;
+
+module_param(recur_count, int, 0644);
+MODULE_PARM_DESC(recur_count, " Recursion level for the stack overflow test");
+module_param(cpoint_name, charp, 0444);
+MODULE_PARM_DESC(cpoint_name, " Crash Point, where kernel is to be crashed");
+module_param(cpoint_type, charp, 0444);
+MODULE_PARM_DESC(cpoint_type, " Crash Point Type, action to be taken on "\
+ "hitting the crash point");
+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 + 1;
+ }
+
+ 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 - 1];
+}
+
+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 - 1];
+}
+
+
+static int lkdtm_parse_commandline(void)
+{
+ int i;
+ unsigned long flags;
+
+ if (cpoint_count < 1 || recur_count < 1)
+ return -EINVAL;
+
+ spin_lock_irqsave(&count_lock, flags);
+ count = cpoint_count;
+ spin_unlock_irqrestore(&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;
+
+ cptype = parse_cp_type(cpoint_type, strlen(cpoint_type));
+ if (cptype == CT_NONE)
+ return -EINVAL;
+
+ for (i = 0; i < ARRAY_SIZE(cp_name); i++) {
+ if (!strcmp(cpoint_name, cp_name[i])) {
+ cpoint = i + 1;
+ return 0;
+ }
+ }
+
+ /* Could not find a valid crash point */
+ return -EINVAL;
+}
+
+static int recursive_loop(int remaining)
+{
+ char buf[REC_STACK_SIZE];
+
+ /* Make sure compiler does not optimize this away. */
+ memset(buf, (remaining & 0xff) | 0x1, REC_STACK_SIZE);
+ if (!remaining)
+ return 0;
+ else
+ return recursive_loop(remaining - 1);
+}
+
+static void do_nothing(void)
+{
+ return;
+}
+
+/* Must immediately follow do_nothing for size calculuations to work out. */
+static void do_overwritten(void)
+{
+ pr_info("do_overwritten wasn't overwritten!\n");
+ return;
+}
+
+static noinline void corrupt_stack(void)
+{
+ /* Use default char array length that triggers stack protection. */
+ char data[8];
+
+ memset((void *)data, 0, 64);
+}
+
+static void noinline execute_location(void *dst)
+{
+ void (*func)(void) = dst;
+
+ pr_info("attempting ok execution at %p\n", do_nothing);
+ do_nothing();
+
+ memcpy(dst, do_nothing, EXEC_SIZE);
+ flush_icache_range((unsigned long)dst, (unsigned long)dst + EXEC_SIZE);
+ pr_info("attempting bad execution at %p\n", func);
+ func();
+}
+
+static void execute_user_location(void *dst)
+{
+ /* Intentionally crossing kernel/user memory boundary. */
+ void (*func)(void) = dst;
+
+ pr_info("attempting ok execution at %p\n", do_nothing);
+ do_nothing();
+
+ if (copy_to_user((void __user *)dst, do_nothing, EXEC_SIZE))
+ return;
+ flush_icache_range((unsigned long)dst, (unsigned long)dst + EXEC_SIZE);
+ pr_info("attempting bad execution at %p\n", func);
+ func();
+}
+
+static void lkdtm_do_action(enum ctype which)
+{
+ switch (which) {
+ case CT_PANIC:
+ panic("dumptest");
+ break;
+ case CT_BUG:
+ BUG();
+ break;
+ case CT_WARNING:
+ WARN_ON(1);
+ break;
+ case CT_EXCEPTION:
+ *((int *) 0) = 0;
+ break;
+ case CT_LOOP:
+ for (;;)
+ ;
+ break;
+ case CT_OVERFLOW:
+ (void) recursive_loop(recur_count);
+ break;
+ case CT_CORRUPT_STACK:
+ corrupt_stack();
+ break;
+ case CT_UNALIGNED_LOAD_STORE_WRITE: {
+ static u8 data[5] __attribute__((aligned(4))) = {1, 2,
+ 3, 4, 5};
+ u32 *p;
+ u32 val = 0x12345678;
+
+ p = (u32 *)(data + 1);
+ if (*p == 0)
+ val = 0x87654321;
+ *p = val;
+ break;
+ }
+ case CT_OVERWRITE_ALLOCATION: {
+ size_t len = 1020;
+ u32 *data = kmalloc(len, GFP_KERNEL);
+
+ data[1024 / sizeof(u32)] = 0x12345678;
+ kfree(data);
+ break;
+ }
+ case CT_WRITE_AFTER_FREE: {
+ int *base, *again;
+ size_t len = 1024;
+ /*
+ * The slub allocator uses the first word to store the free
+ * pointer in some configurations. Use the middle of the
+ * allocation to avoid running into the freelist
+ */
+ size_t offset = (len / sizeof(*base)) / 2;
+
+ base = kmalloc(len, GFP_KERNEL);
+ pr_info("Allocated memory %p-%p\n", base, &base[offset * 2]);
+ pr_info("Attempting bad write to freed memory at %p\n",
+ &base[offset]);
+ kfree(base);
+ base[offset] = 0x0abcdef0;
+ /* Attempt to notice the overwrite. */
+ again = kmalloc(len, GFP_KERNEL);
+ kfree(again);
+ if (again != base)
+ pr_info("Hmm, didn't get the same memory range.\n");
+
+ break;
+ }
+ case CT_READ_AFTER_FREE: {
+ int *base, *val, saw;
+ size_t len = 1024;
+ /*
+ * The slub allocator uses the first word to store the free
+ * pointer in some configurations. Use the middle of the
+ * allocation to avoid running into the freelist
+ */
+ size_t offset = (len / sizeof(*base)) / 2;
+
+ base = kmalloc(len, GFP_KERNEL);
+ if (!base)
+ break;
+
+ val = kmalloc(len, GFP_KERNEL);
+ if (!val) {
+ kfree(base);
+ break;
+ }
+
+ *val = 0x12345678;
+ base[offset] = *val;
+ pr_info("Value in memory before free: %x\n", base[offset]);
+
+ kfree(base);
+
+ pr_info("Attempting bad read from freed memory\n");
+ saw = base[offset];
+ if (saw != *val) {
+ /* Good! Poisoning happened, so declare a win. */
+ pr_info("Memory correctly poisoned (%x)\n", saw);
+ BUG();
+ }
+ pr_info("Memory was not poisoned\n");
+
+ kfree(val);
+ break;
+ }
+ case CT_WRITE_BUDDY_AFTER_FREE: {
+ unsigned long p = __get_free_page(GFP_KERNEL);
+ if (!p)
+ break;
+ pr_info("Writing to the buddy page before free\n");
+ memset((void *)p, 0x3, PAGE_SIZE);
+ free_page(p);
+ schedule();
+ pr_info("Attempting bad write to the buddy page after free\n");
+ memset((void *)p, 0x78, PAGE_SIZE);
+ /* Attempt to notice the overwrite. */
+ p = __get_free_page(GFP_KERNEL);
+ free_page(p);
+ schedule();
+
+ break;
+ }
+ case CT_READ_BUDDY_AFTER_FREE: {
+ unsigned long p = __get_free_page(GFP_KERNEL);
+ int saw, *val;
+ int *base;
+
+ if (!p)
+ break;
+
+ val = kmalloc(1024, GFP_KERNEL);
+ if (!val) {
+ free_page(p);
+ break;
+ }
+
+ base = (int *)p;
+
+ *val = 0x12345678;
+ base[0] = *val;
+ pr_info("Value in memory before free: %x\n", base[0]);
+ free_page(p);
+ pr_info("Attempting to read from freed memory\n");
+ saw = base[0];
+ if (saw != *val) {
+ /* Good! Poisoning happened, so declare a win. */
+ pr_info("Memory correctly poisoned (%x)\n", saw);
+ BUG();
+ }
+ pr_info("Buddy page was not poisoned\n");
+
+ kfree(val);
+ break;
+ }
+ case CT_SOFTLOCKUP:
+ preempt_disable();
+ for (;;)
+ cpu_relax();
+ break;
+ case CT_HARDLOCKUP:
+ local_irq_disable();
+ for (;;)
+ cpu_relax();
+ break;
+ case CT_SPINLOCKUP:
+ /* Must be called twice to trigger. */
+ spin_lock(&lock_me_up);
+ /* Let sparse know we intended to exit holding the lock. */
+ __release(&lock_me_up);
+ break;
+ case CT_HUNG_TASK:
+ set_current_state(TASK_UNINTERRUPTIBLE);
+ schedule();
+ break;
+ case CT_EXEC_DATA:
+ execute_location(data_area);
+ break;
+ case CT_EXEC_STACK: {
+ u8 stack_area[EXEC_SIZE];
+ execute_location(stack_area);
+ break;
+ }
+ case CT_EXEC_KMALLOC: {
+ u32 *kmalloc_area = kmalloc(EXEC_SIZE, GFP_KERNEL);
+ execute_location(kmalloc_area);
+ kfree(kmalloc_area);
+ break;
+ }
+ case CT_EXEC_VMALLOC: {
+ u32 *vmalloc_area = vmalloc(EXEC_SIZE);
+ execute_location(vmalloc_area);
+ vfree(vmalloc_area);
+ break;
+ }
+ case CT_EXEC_USERSPACE: {
+ unsigned long user_addr;
+
+ user_addr = vm_mmap(NULL, 0, PAGE_SIZE,
+ PROT_READ | PROT_WRITE | PROT_EXEC,
+ MAP_ANONYMOUS | MAP_PRIVATE, 0);
+ if (user_addr >= TASK_SIZE) {
+ pr_warn("Failed to allocate user memory\n");
+ return;
+ }
+ execute_user_location((void *)user_addr);
+ vm_munmap(user_addr, PAGE_SIZE);
+ break;
+ }
+ case CT_ACCESS_USERSPACE: {
+ unsigned long user_addr, tmp = 0;
+ unsigned long *ptr;
+
+ user_addr = vm_mmap(NULL, 0, PAGE_SIZE,
+ PROT_READ | PROT_WRITE | PROT_EXEC,
+ MAP_ANONYMOUS | MAP_PRIVATE, 0);
+ if (user_addr >= TASK_SIZE) {
+ pr_warn("Failed to allocate user memory\n");
+ return;
+ }
+
+ if (copy_to_user((void __user *)user_addr, &tmp, sizeof(tmp))) {
+ pr_warn("copy_to_user failed\n");
+ vm_munmap(user_addr, PAGE_SIZE);
+ return;
+ }
+
+ ptr = (unsigned long *)user_addr;
+
+ pr_info("attempting bad read at %p\n", ptr);
+ tmp = *ptr;
+ tmp += 0xc0dec0de;
+
+ pr_info("attempting bad write at %p\n", ptr);
+ *ptr = tmp;
+
+ vm_munmap(user_addr, PAGE_SIZE);
+
+ break;
+ }
+ case CT_WRITE_RO: {
+ /* Explicitly cast away "const" for the test. */
+ unsigned long *ptr = (unsigned long *)&rodata;
+
+ pr_info("attempting bad rodata write at %p\n", ptr);
+ *ptr ^= 0xabcd1234;
+
+ break;
+ }
+ case CT_WRITE_RO_AFTER_INIT: {
+ unsigned long *ptr = &ro_after_init;
+
+ /*
+ * Verify we were written to during init. Since an Oops
+ * is considered a "success", a failure is to just skip the
+ * real test.
+ */
+ if ((*ptr & 0xAA) != 0xAA) {
+ pr_info("%p was NOT written during init!?\n", ptr);
+ break;
+ }
+
+ pr_info("attempting bad ro_after_init write at %p\n", ptr);
+ *ptr ^= 0xabcd1234;
+
+ break;
+ }
+ case CT_WRITE_KERN: {
+ size_t size;
+ unsigned char *ptr;
+
+ size = (unsigned long)do_overwritten -
+ (unsigned long)do_nothing;
+ ptr = (unsigned char *)do_overwritten;
+
+ pr_info("attempting bad %zu byte write at %p\n", size, ptr);
+ memcpy(ptr, (unsigned char *)do_nothing, size);
+ flush_icache_range((unsigned long)ptr,
+ (unsigned long)(ptr + size));
+
+ do_overwritten();
+ break;
+ }
+ case CT_WRAP_ATOMIC: {
+ atomic_t under = ATOMIC_INIT(INT_MIN);
+ atomic_t over = ATOMIC_INIT(INT_MAX);
+
+ pr_info("attempting atomic underflow\n");
+ atomic_dec(&under);
+ pr_info("attempting atomic overflow\n");
+ atomic_inc(&over);
+
+ return;
+ }
+ case CT_NONE:
+ default:
+ break;
+ }
+
+}
+
+static void lkdtm_handler(void)
+{
+ unsigned long flags;
+ bool do_it = false;
+
+ spin_lock_irqsave(&count_lock, flags);
+ count--;
+ pr_info("Crash point %s of type %s hit, trigger in %d rounds\n",
+ cp_name_to_str(cpoint), cp_type_to_str(cptype), count);
+
+ if (count == 0) {
+ do_it = true;
+ count = cpoint_count;
+ }
+ spin_unlock_irqrestore(&count_lock, flags);
+
+ if (do_it)
+ lkdtm_do_action(cptype);
+}
+
+static int lkdtm_register_cpoint(enum cname which)
+{
+ int ret;
+
+ cpoint = CN_INVALID;
+ if (lkdtm.entry != NULL)
+ unregister_jprobe(&lkdtm);
+
+ switch (which) {
+ case CN_DIRECT:
+ lkdtm_do_action(cptype);
+ return 0;
+ case CN_INT_HARDWARE_ENTRY:
+ lkdtm.kp.symbol_name = "do_IRQ";
+ lkdtm.entry = (kprobe_opcode_t*) jp_do_irq;
+ break;
+ case CN_INT_HW_IRQ_EN:
+ lkdtm.kp.symbol_name = "handle_IRQ_event";
+ lkdtm.entry = (kprobe_opcode_t*) jp_handle_irq_event;
+ break;
+ case CN_INT_TASKLET_ENTRY:
+ lkdtm.kp.symbol_name = "tasklet_action";
+ lkdtm.entry = (kprobe_opcode_t*) jp_tasklet_action;
+ break;
+ case CN_FS_DEVRW:
+ lkdtm.kp.symbol_name = "ll_rw_block";
+ lkdtm.entry = (kprobe_opcode_t*) jp_ll_rw_block;
+ break;
+ case CN_MEM_SWAPOUT:
+ lkdtm.kp.symbol_name = "shrink_inactive_list";
+ lkdtm.entry = (kprobe_opcode_t*) jp_shrink_inactive_list;
+ break;
+ case CN_TIMERADD:
+ lkdtm.kp.symbol_name = "hrtimer_start";
+ lkdtm.entry = (kprobe_opcode_t*) jp_hrtimer_start;
+ break;
+ case CN_SCSI_DISPATCH_CMD:
+ lkdtm.kp.symbol_name = "scsi_dispatch_cmd";
+ lkdtm.entry = (kprobe_opcode_t*) jp_scsi_dispatch_cmd;
+ break;
+ case CN_IDE_CORE_CP:
+#ifdef CONFIG_IDE
+ lkdtm.kp.symbol_name = "generic_ide_ioctl";
+ lkdtm.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;
+ }
+
+ cpoint = which;
+ if ((ret = register_jprobe(&lkdtm)) < 0) {
+ pr_info("Couldn't register jprobe\n");
+ cpoint = 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);
+
+ cptype = parse_cp_type(buf, count);
+ free_page((unsigned long) buf);
+
+ if (cptype == 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;
+
+ /* Make sure we can write to __ro_after_init values during __init */
+ ro_after_init |= 0xAA;
+
+ /* 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 (cpoint != CN_INVALID && cptype != CT_NONE) {
+ ret = lkdtm_register_cpoint(cpoint);
+ if (ret < 0) {
+ pr_info("Invalid crash point %d\n", cpoint);
+ 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);
+
+ unregister_jprobe(&lkdtm);
+ 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");
--
2.7.4
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