Vivek Goyal | 666bfdd | 2005-06-25 14:58:21 -0700 | [diff] [blame] | 1 | /* |
| 2 | * fs/proc/vmcore.c Interface for accessing the crash |
| 3 | * dump from the system's previous life. |
| 4 | * Heavily borrowed from fs/proc/kcore.c |
| 5 | * Created by: Hariprasad Nellitheertha (hari@in.ibm.com) |
| 6 | * Copyright (C) IBM Corporation, 2004. All rights reserved |
| 7 | * |
| 8 | */ |
| 9 | |
Vivek Goyal | 666bfdd | 2005-06-25 14:58:21 -0700 | [diff] [blame] | 10 | #include <linux/mm.h> |
David Howells | 2f96b8c | 2013-04-12 00:10:25 +0100 | [diff] [blame] | 11 | #include <linux/kcore.h> |
Vivek Goyal | 666bfdd | 2005-06-25 14:58:21 -0700 | [diff] [blame] | 12 | #include <linux/user.h> |
Vivek Goyal | 666bfdd | 2005-06-25 14:58:21 -0700 | [diff] [blame] | 13 | #include <linux/elf.h> |
| 14 | #include <linux/elfcore.h> |
Paul Gortmaker | afeacc8 | 2011-05-26 16:00:52 -0400 | [diff] [blame] | 15 | #include <linux/export.h> |
Tejun Heo | 5a0e3ad | 2010-03-24 17:04:11 +0900 | [diff] [blame] | 16 | #include <linux/slab.h> |
Vivek Goyal | 666bfdd | 2005-06-25 14:58:21 -0700 | [diff] [blame] | 17 | #include <linux/highmem.h> |
Andrew Morton | 87ebdc0 | 2013-02-27 17:03:16 -0800 | [diff] [blame] | 18 | #include <linux/printk.h> |
Vivek Goyal | 666bfdd | 2005-06-25 14:58:21 -0700 | [diff] [blame] | 19 | #include <linux/bootmem.h> |
| 20 | #include <linux/init.h> |
| 21 | #include <linux/crash_dump.h> |
| 22 | #include <linux/list.h> |
HATAYAMA Daisuke | 8308697 | 2013-07-03 15:02:23 -0700 | [diff] [blame] | 23 | #include <linux/vmalloc.h> |
Vivek Goyal | 666bfdd | 2005-06-25 14:58:21 -0700 | [diff] [blame] | 24 | #include <asm/uaccess.h> |
| 25 | #include <asm/io.h> |
David Howells | 2f96b8c | 2013-04-12 00:10:25 +0100 | [diff] [blame] | 26 | #include "internal.h" |
Vivek Goyal | 666bfdd | 2005-06-25 14:58:21 -0700 | [diff] [blame] | 27 | |
| 28 | /* List representing chunks of contiguous memory areas and their offsets in |
| 29 | * vmcore file. |
| 30 | */ |
| 31 | static LIST_HEAD(vmcore_list); |
| 32 | |
| 33 | /* Stores the pointer to the buffer containing kernel elf core headers. */ |
| 34 | static char *elfcorebuf; |
| 35 | static size_t elfcorebuf_sz; |
HATAYAMA Daisuke | f2bdacd | 2013-07-03 15:02:14 -0700 | [diff] [blame] | 36 | static size_t elfcorebuf_sz_orig; |
Vivek Goyal | 666bfdd | 2005-06-25 14:58:21 -0700 | [diff] [blame] | 37 | |
HATAYAMA Daisuke | 087350c | 2013-07-03 15:02:19 -0700 | [diff] [blame] | 38 | static char *elfnotes_buf; |
| 39 | static size_t elfnotes_sz; |
| 40 | |
Vivek Goyal | 666bfdd | 2005-06-25 14:58:21 -0700 | [diff] [blame] | 41 | /* Total size of vmcore file. */ |
| 42 | static u64 vmcore_size; |
| 43 | |
Alexey Dobriyan | 5aa140c | 2008-10-06 14:36:31 +0400 | [diff] [blame] | 44 | static struct proc_dir_entry *proc_vmcore = NULL; |
Vivek Goyal | 666bfdd | 2005-06-25 14:58:21 -0700 | [diff] [blame] | 45 | |
Olaf Hering | 997c136 | 2011-05-26 16:25:54 -0700 | [diff] [blame] | 46 | /* |
| 47 | * Returns > 0 for RAM pages, 0 for non-RAM pages, < 0 on error |
| 48 | * The called function has to take care of module refcounting. |
| 49 | */ |
| 50 | static int (*oldmem_pfn_is_ram)(unsigned long pfn); |
| 51 | |
| 52 | int register_oldmem_pfn_is_ram(int (*fn)(unsigned long pfn)) |
| 53 | { |
| 54 | if (oldmem_pfn_is_ram) |
| 55 | return -EBUSY; |
| 56 | oldmem_pfn_is_ram = fn; |
| 57 | return 0; |
| 58 | } |
| 59 | EXPORT_SYMBOL_GPL(register_oldmem_pfn_is_ram); |
| 60 | |
| 61 | void unregister_oldmem_pfn_is_ram(void) |
| 62 | { |
| 63 | oldmem_pfn_is_ram = NULL; |
| 64 | wmb(); |
| 65 | } |
| 66 | EXPORT_SYMBOL_GPL(unregister_oldmem_pfn_is_ram); |
| 67 | |
| 68 | static int pfn_is_ram(unsigned long pfn) |
| 69 | { |
| 70 | int (*fn)(unsigned long pfn); |
| 71 | /* pfn is ram unless fn() checks pagetype */ |
| 72 | int ret = 1; |
| 73 | |
| 74 | /* |
| 75 | * Ask hypervisor if the pfn is really ram. |
| 76 | * A ballooned page contains no data and reading from such a page |
| 77 | * will cause high load in the hypervisor. |
| 78 | */ |
| 79 | fn = oldmem_pfn_is_ram; |
| 80 | if (fn) |
| 81 | ret = fn(pfn); |
| 82 | |
| 83 | return ret; |
| 84 | } |
| 85 | |
Vivek Goyal | 666bfdd | 2005-06-25 14:58:21 -0700 | [diff] [blame] | 86 | /* Reads a page from the oldmem device from given offset. */ |
| 87 | static ssize_t read_from_oldmem(char *buf, size_t count, |
Vivek Goyal | 9e9e394 | 2006-01-11 12:17:37 -0800 | [diff] [blame] | 88 | u64 *ppos, int userbuf) |
Vivek Goyal | 666bfdd | 2005-06-25 14:58:21 -0700 | [diff] [blame] | 89 | { |
| 90 | unsigned long pfn, offset; |
| 91 | size_t nr_bytes; |
| 92 | ssize_t read = 0, tmp; |
| 93 | |
| 94 | if (!count) |
| 95 | return 0; |
| 96 | |
| 97 | offset = (unsigned long)(*ppos % PAGE_SIZE); |
| 98 | pfn = (unsigned long)(*ppos / PAGE_SIZE); |
Vivek Goyal | 666bfdd | 2005-06-25 14:58:21 -0700 | [diff] [blame] | 99 | |
| 100 | do { |
| 101 | if (count > (PAGE_SIZE - offset)) |
| 102 | nr_bytes = PAGE_SIZE - offset; |
| 103 | else |
| 104 | nr_bytes = count; |
| 105 | |
Olaf Hering | 997c136 | 2011-05-26 16:25:54 -0700 | [diff] [blame] | 106 | /* If pfn is not ram, return zeros for sparse dump files */ |
| 107 | if (pfn_is_ram(pfn) == 0) |
| 108 | memset(buf, 0, nr_bytes); |
| 109 | else { |
| 110 | tmp = copy_oldmem_page(pfn, buf, nr_bytes, |
| 111 | offset, userbuf); |
| 112 | if (tmp < 0) |
| 113 | return tmp; |
| 114 | } |
Vivek Goyal | 666bfdd | 2005-06-25 14:58:21 -0700 | [diff] [blame] | 115 | *ppos += nr_bytes; |
| 116 | count -= nr_bytes; |
| 117 | buf += nr_bytes; |
| 118 | read += nr_bytes; |
| 119 | ++pfn; |
| 120 | offset = 0; |
| 121 | } while (count); |
| 122 | |
| 123 | return read; |
| 124 | } |
| 125 | |
Vivek Goyal | 666bfdd | 2005-06-25 14:58:21 -0700 | [diff] [blame] | 126 | /* Read from the ELF header and then the crash dump. On error, negative value is |
| 127 | * returned otherwise number of bytes read are returned. |
| 128 | */ |
| 129 | static ssize_t read_vmcore(struct file *file, char __user *buffer, |
| 130 | size_t buflen, loff_t *fpos) |
| 131 | { |
| 132 | ssize_t acc = 0, tmp; |
Vivek Goyal | 80e8ff6 | 2006-04-10 22:54:10 -0700 | [diff] [blame] | 133 | size_t tsz; |
HATAYAMA Daisuke | b27eb18 | 2013-07-03 15:02:13 -0700 | [diff] [blame] | 134 | u64 start; |
| 135 | struct vmcore *m = NULL; |
Vivek Goyal | 666bfdd | 2005-06-25 14:58:21 -0700 | [diff] [blame] | 136 | |
| 137 | if (buflen == 0 || *fpos >= vmcore_size) |
| 138 | return 0; |
| 139 | |
| 140 | /* trim buflen to not go beyond EOF */ |
| 141 | if (buflen > vmcore_size - *fpos) |
| 142 | buflen = vmcore_size - *fpos; |
| 143 | |
| 144 | /* Read ELF core header */ |
| 145 | if (*fpos < elfcorebuf_sz) { |
HATAYAMA Daisuke | 087350c | 2013-07-03 15:02:19 -0700 | [diff] [blame] | 146 | tsz = min(elfcorebuf_sz - (size_t)*fpos, buflen); |
Vivek Goyal | 666bfdd | 2005-06-25 14:58:21 -0700 | [diff] [blame] | 147 | if (copy_to_user(buffer, elfcorebuf + *fpos, tsz)) |
| 148 | return -EFAULT; |
| 149 | buflen -= tsz; |
| 150 | *fpos += tsz; |
| 151 | buffer += tsz; |
| 152 | acc += tsz; |
| 153 | |
| 154 | /* leave now if filled buffer already */ |
| 155 | if (buflen == 0) |
| 156 | return acc; |
| 157 | } |
| 158 | |
HATAYAMA Daisuke | 087350c | 2013-07-03 15:02:19 -0700 | [diff] [blame] | 159 | /* Read Elf note segment */ |
| 160 | if (*fpos < elfcorebuf_sz + elfnotes_sz) { |
| 161 | void *kaddr; |
| 162 | |
| 163 | tsz = min(elfcorebuf_sz + elfnotes_sz - (size_t)*fpos, buflen); |
| 164 | kaddr = elfnotes_buf + *fpos - elfcorebuf_sz; |
| 165 | if (copy_to_user(buffer, kaddr, tsz)) |
| 166 | return -EFAULT; |
| 167 | buflen -= tsz; |
| 168 | *fpos += tsz; |
| 169 | buffer += tsz; |
| 170 | acc += tsz; |
| 171 | |
| 172 | /* leave now if filled buffer already */ |
| 173 | if (buflen == 0) |
| 174 | return acc; |
| 175 | } |
| 176 | |
HATAYAMA Daisuke | b27eb18 | 2013-07-03 15:02:13 -0700 | [diff] [blame] | 177 | list_for_each_entry(m, &vmcore_list, list) { |
| 178 | if (*fpos < m->offset + m->size) { |
HATAYAMA Daisuke | 087350c | 2013-07-03 15:02:19 -0700 | [diff] [blame] | 179 | tsz = min_t(size_t, m->offset + m->size - *fpos, buflen); |
HATAYAMA Daisuke | b27eb18 | 2013-07-03 15:02:13 -0700 | [diff] [blame] | 180 | start = m->paddr + *fpos - m->offset; |
| 181 | tmp = read_from_oldmem(buffer, tsz, &start, 1); |
| 182 | if (tmp < 0) |
| 183 | return tmp; |
| 184 | buflen -= tsz; |
| 185 | *fpos += tsz; |
| 186 | buffer += tsz; |
| 187 | acc += tsz; |
Vivek Goyal | 666bfdd | 2005-06-25 14:58:21 -0700 | [diff] [blame] | 188 | |
HATAYAMA Daisuke | b27eb18 | 2013-07-03 15:02:13 -0700 | [diff] [blame] | 189 | /* leave now if filled buffer already */ |
| 190 | if (buflen == 0) |
| 191 | return acc; |
Vivek Goyal | 666bfdd | 2005-06-25 14:58:21 -0700 | [diff] [blame] | 192 | } |
Vivek Goyal | 666bfdd | 2005-06-25 14:58:21 -0700 | [diff] [blame] | 193 | } |
HATAYAMA Daisuke | b27eb18 | 2013-07-03 15:02:13 -0700 | [diff] [blame] | 194 | |
Vivek Goyal | 666bfdd | 2005-06-25 14:58:21 -0700 | [diff] [blame] | 195 | return acc; |
| 196 | } |
| 197 | |
HATAYAMA Daisuke | 8308697 | 2013-07-03 15:02:23 -0700 | [diff] [blame] | 198 | /** |
| 199 | * alloc_elfnotes_buf - allocate buffer for ELF note segment in |
| 200 | * vmalloc memory |
| 201 | * |
| 202 | * @notes_sz: size of buffer |
| 203 | * |
| 204 | * If CONFIG_MMU is defined, use vmalloc_user() to allow users to mmap |
| 205 | * the buffer to user-space by means of remap_vmalloc_range(). |
| 206 | * |
| 207 | * If CONFIG_MMU is not defined, use vzalloc() since mmap_vmcore() is |
| 208 | * disabled and there's no need to allow users to mmap the buffer. |
| 209 | */ |
| 210 | static inline char *alloc_elfnotes_buf(size_t notes_sz) |
| 211 | { |
| 212 | #ifdef CONFIG_MMU |
| 213 | return vmalloc_user(notes_sz); |
| 214 | #else |
| 215 | return vzalloc(notes_sz); |
| 216 | #endif |
| 217 | } |
| 218 | |
| 219 | /* |
| 220 | * Disable mmap_vmcore() if CONFIG_MMU is not defined. MMU is |
| 221 | * essential for mmap_vmcore() in order to map physically |
| 222 | * non-contiguous objects (ELF header, ELF note segment and memory |
| 223 | * regions in the 1st kernel pointed to by PT_LOAD entries) into |
| 224 | * virtually contiguous user-space in ELF layout. |
| 225 | */ |
| 226 | #ifdef CONFIG_MMU |
| 227 | static int mmap_vmcore(struct file *file, struct vm_area_struct *vma) |
| 228 | { |
| 229 | size_t size = vma->vm_end - vma->vm_start; |
| 230 | u64 start, end, len, tsz; |
| 231 | struct vmcore *m; |
| 232 | |
| 233 | start = (u64)vma->vm_pgoff << PAGE_SHIFT; |
| 234 | end = start + size; |
| 235 | |
| 236 | if (size > vmcore_size || end > vmcore_size) |
| 237 | return -EINVAL; |
| 238 | |
| 239 | if (vma->vm_flags & (VM_WRITE | VM_EXEC)) |
| 240 | return -EPERM; |
| 241 | |
| 242 | vma->vm_flags &= ~(VM_MAYWRITE | VM_MAYEXEC); |
| 243 | vma->vm_flags |= VM_MIXEDMAP; |
| 244 | |
| 245 | len = 0; |
| 246 | |
| 247 | if (start < elfcorebuf_sz) { |
| 248 | u64 pfn; |
| 249 | |
| 250 | tsz = min(elfcorebuf_sz - (size_t)start, size); |
| 251 | pfn = __pa(elfcorebuf + start) >> PAGE_SHIFT; |
| 252 | if (remap_pfn_range(vma, vma->vm_start, pfn, tsz, |
| 253 | vma->vm_page_prot)) |
| 254 | return -EAGAIN; |
| 255 | size -= tsz; |
| 256 | start += tsz; |
| 257 | len += tsz; |
| 258 | |
| 259 | if (size == 0) |
| 260 | return 0; |
| 261 | } |
| 262 | |
| 263 | if (start < elfcorebuf_sz + elfnotes_sz) { |
| 264 | void *kaddr; |
| 265 | |
| 266 | tsz = min(elfcorebuf_sz + elfnotes_sz - (size_t)start, size); |
| 267 | kaddr = elfnotes_buf + start - elfcorebuf_sz; |
| 268 | if (remap_vmalloc_range_partial(vma, vma->vm_start + len, |
| 269 | kaddr, tsz)) |
| 270 | goto fail; |
| 271 | size -= tsz; |
| 272 | start += tsz; |
| 273 | len += tsz; |
| 274 | |
| 275 | if (size == 0) |
| 276 | return 0; |
| 277 | } |
| 278 | |
| 279 | list_for_each_entry(m, &vmcore_list, list) { |
| 280 | if (start < m->offset + m->size) { |
| 281 | u64 paddr = 0; |
| 282 | |
| 283 | tsz = min_t(size_t, m->offset + m->size - start, size); |
| 284 | paddr = m->paddr + start - m->offset; |
| 285 | if (remap_pfn_range(vma, vma->vm_start + len, |
| 286 | paddr >> PAGE_SHIFT, tsz, |
| 287 | vma->vm_page_prot)) |
| 288 | goto fail; |
| 289 | size -= tsz; |
| 290 | start += tsz; |
| 291 | len += tsz; |
| 292 | |
| 293 | if (size == 0) |
| 294 | return 0; |
| 295 | } |
| 296 | } |
| 297 | |
| 298 | return 0; |
| 299 | fail: |
| 300 | do_munmap(vma->vm_mm, vma->vm_start, len); |
| 301 | return -EAGAIN; |
| 302 | } |
| 303 | #else |
| 304 | static int mmap_vmcore(struct file *file, struct vm_area_struct *vma) |
| 305 | { |
| 306 | return -ENOSYS; |
| 307 | } |
| 308 | #endif |
| 309 | |
Alexey Dobriyan | 5aa140c | 2008-10-06 14:36:31 +0400 | [diff] [blame] | 310 | static const struct file_operations proc_vmcore_operations = { |
Vivek Goyal | 666bfdd | 2005-06-25 14:58:21 -0700 | [diff] [blame] | 311 | .read = read_vmcore, |
Arnd Bergmann | c227e69 | 2010-09-22 13:04:54 -0700 | [diff] [blame] | 312 | .llseek = default_llseek, |
HATAYAMA Daisuke | 8308697 | 2013-07-03 15:02:23 -0700 | [diff] [blame] | 313 | .mmap = mmap_vmcore, |
Vivek Goyal | 666bfdd | 2005-06-25 14:58:21 -0700 | [diff] [blame] | 314 | }; |
| 315 | |
| 316 | static struct vmcore* __init get_new_element(void) |
| 317 | { |
Cyrill Gorcunov | 2f6d311 | 2009-06-17 16:26:00 -0700 | [diff] [blame] | 318 | return kzalloc(sizeof(struct vmcore), GFP_KERNEL); |
Vivek Goyal | 666bfdd | 2005-06-25 14:58:21 -0700 | [diff] [blame] | 319 | } |
| 320 | |
HATAYAMA Daisuke | 591ff71 | 2013-07-03 15:02:22 -0700 | [diff] [blame] | 321 | static u64 __init get_vmcore_size(size_t elfsz, size_t elfnotesegsz, |
| 322 | struct list_head *vc_list) |
Vivek Goyal | 666bfdd | 2005-06-25 14:58:21 -0700 | [diff] [blame] | 323 | { |
Vivek Goyal | 666bfdd | 2005-06-25 14:58:21 -0700 | [diff] [blame] | 324 | u64 size; |
HATAYAMA Daisuke | 591ff71 | 2013-07-03 15:02:22 -0700 | [diff] [blame] | 325 | struct vmcore *m; |
Vivek Goyal | 666bfdd | 2005-06-25 14:58:21 -0700 | [diff] [blame] | 326 | |
HATAYAMA Daisuke | 591ff71 | 2013-07-03 15:02:22 -0700 | [diff] [blame] | 327 | size = elfsz + elfnotesegsz; |
| 328 | list_for_each_entry(m, vc_list, list) { |
| 329 | size += m->size; |
Vivek Goyal | 72658e9 | 2005-06-25 14:58:22 -0700 | [diff] [blame] | 330 | } |
| 331 | return size; |
| 332 | } |
| 333 | |
HATAYAMA Daisuke | 087350c | 2013-07-03 15:02:19 -0700 | [diff] [blame] | 334 | /** |
| 335 | * update_note_header_size_elf64 - update p_memsz member of each PT_NOTE entry |
| 336 | * |
| 337 | * @ehdr_ptr: ELF header |
| 338 | * |
| 339 | * This function updates p_memsz member of each PT_NOTE entry in the |
| 340 | * program header table pointed to by @ehdr_ptr to real size of ELF |
| 341 | * note segment. |
| 342 | */ |
| 343 | static int __init update_note_header_size_elf64(const Elf64_Ehdr *ehdr_ptr) |
Vivek Goyal | 666bfdd | 2005-06-25 14:58:21 -0700 | [diff] [blame] | 344 | { |
HATAYAMA Daisuke | 087350c | 2013-07-03 15:02:19 -0700 | [diff] [blame] | 345 | int i, rc=0; |
| 346 | Elf64_Phdr *phdr_ptr; |
Vivek Goyal | 666bfdd | 2005-06-25 14:58:21 -0700 | [diff] [blame] | 347 | Elf64_Nhdr *nhdr_ptr; |
Vivek Goyal | 666bfdd | 2005-06-25 14:58:21 -0700 | [diff] [blame] | 348 | |
HATAYAMA Daisuke | 087350c | 2013-07-03 15:02:19 -0700 | [diff] [blame] | 349 | phdr_ptr = (Elf64_Phdr *)(ehdr_ptr + 1); |
Vivek Goyal | 666bfdd | 2005-06-25 14:58:21 -0700 | [diff] [blame] | 350 | for (i = 0; i < ehdr_ptr->e_phnum; i++, phdr_ptr++) { |
Vivek Goyal | 666bfdd | 2005-06-25 14:58:21 -0700 | [diff] [blame] | 351 | void *notes_section; |
Vivek Goyal | 666bfdd | 2005-06-25 14:58:21 -0700 | [diff] [blame] | 352 | u64 offset, max_sz, sz, real_sz = 0; |
| 353 | if (phdr_ptr->p_type != PT_NOTE) |
| 354 | continue; |
Vivek Goyal | 666bfdd | 2005-06-25 14:58:21 -0700 | [diff] [blame] | 355 | max_sz = phdr_ptr->p_memsz; |
| 356 | offset = phdr_ptr->p_offset; |
| 357 | notes_section = kmalloc(max_sz, GFP_KERNEL); |
| 358 | if (!notes_section) |
| 359 | return -ENOMEM; |
| 360 | rc = read_from_oldmem(notes_section, max_sz, &offset, 0); |
| 361 | if (rc < 0) { |
| 362 | kfree(notes_section); |
| 363 | return rc; |
| 364 | } |
| 365 | nhdr_ptr = notes_section; |
HATAYAMA Daisuke | 087350c | 2013-07-03 15:02:19 -0700 | [diff] [blame] | 366 | while (real_sz < max_sz) { |
Vivek Goyal | 666bfdd | 2005-06-25 14:58:21 -0700 | [diff] [blame] | 367 | if (nhdr_ptr->n_namesz == 0) |
| 368 | break; |
| 369 | sz = sizeof(Elf64_Nhdr) + |
| 370 | ((nhdr_ptr->n_namesz + 3) & ~3) + |
| 371 | ((nhdr_ptr->n_descsz + 3) & ~3); |
| 372 | real_sz += sz; |
| 373 | nhdr_ptr = (Elf64_Nhdr*)((char*)nhdr_ptr + sz); |
| 374 | } |
Vivek Goyal | 666bfdd | 2005-06-25 14:58:21 -0700 | [diff] [blame] | 375 | kfree(notes_section); |
HATAYAMA Daisuke | 087350c | 2013-07-03 15:02:19 -0700 | [diff] [blame] | 376 | phdr_ptr->p_memsz = real_sz; |
Vivek Goyal | 666bfdd | 2005-06-25 14:58:21 -0700 | [diff] [blame] | 377 | } |
| 378 | |
HATAYAMA Daisuke | 087350c | 2013-07-03 15:02:19 -0700 | [diff] [blame] | 379 | return 0; |
| 380 | } |
| 381 | |
| 382 | /** |
| 383 | * get_note_number_and_size_elf64 - get the number of PT_NOTE program |
| 384 | * headers and sum of real size of their ELF note segment headers and |
| 385 | * data. |
| 386 | * |
| 387 | * @ehdr_ptr: ELF header |
| 388 | * @nr_ptnote: buffer for the number of PT_NOTE program headers |
| 389 | * @sz_ptnote: buffer for size of unique PT_NOTE program header |
| 390 | * |
| 391 | * This function is used to merge multiple PT_NOTE program headers |
| 392 | * into a unique single one. The resulting unique entry will have |
| 393 | * @sz_ptnote in its phdr->p_mem. |
| 394 | * |
| 395 | * It is assumed that program headers with PT_NOTE type pointed to by |
| 396 | * @ehdr_ptr has already been updated by update_note_header_size_elf64 |
| 397 | * and each of PT_NOTE program headers has actual ELF note segment |
| 398 | * size in its p_memsz member. |
| 399 | */ |
| 400 | static int __init get_note_number_and_size_elf64(const Elf64_Ehdr *ehdr_ptr, |
| 401 | int *nr_ptnote, u64 *sz_ptnote) |
| 402 | { |
| 403 | int i; |
| 404 | Elf64_Phdr *phdr_ptr; |
| 405 | |
| 406 | *nr_ptnote = *sz_ptnote = 0; |
| 407 | |
| 408 | phdr_ptr = (Elf64_Phdr *)(ehdr_ptr + 1); |
| 409 | for (i = 0; i < ehdr_ptr->e_phnum; i++, phdr_ptr++) { |
| 410 | if (phdr_ptr->p_type != PT_NOTE) |
| 411 | continue; |
| 412 | *nr_ptnote += 1; |
| 413 | *sz_ptnote += phdr_ptr->p_memsz; |
| 414 | } |
| 415 | |
| 416 | return 0; |
| 417 | } |
| 418 | |
| 419 | /** |
| 420 | * copy_notes_elf64 - copy ELF note segments in a given buffer |
| 421 | * |
| 422 | * @ehdr_ptr: ELF header |
| 423 | * @notes_buf: buffer into which ELF note segments are copied |
| 424 | * |
| 425 | * This function is used to copy ELF note segment in the 1st kernel |
| 426 | * into the buffer @notes_buf in the 2nd kernel. It is assumed that |
| 427 | * size of the buffer @notes_buf is equal to or larger than sum of the |
| 428 | * real ELF note segment headers and data. |
| 429 | * |
| 430 | * It is assumed that program headers with PT_NOTE type pointed to by |
| 431 | * @ehdr_ptr has already been updated by update_note_header_size_elf64 |
| 432 | * and each of PT_NOTE program headers has actual ELF note segment |
| 433 | * size in its p_memsz member. |
| 434 | */ |
| 435 | static int __init copy_notes_elf64(const Elf64_Ehdr *ehdr_ptr, char *notes_buf) |
| 436 | { |
| 437 | int i, rc=0; |
| 438 | Elf64_Phdr *phdr_ptr; |
| 439 | |
| 440 | phdr_ptr = (Elf64_Phdr*)(ehdr_ptr + 1); |
| 441 | |
| 442 | for (i = 0; i < ehdr_ptr->e_phnum; i++, phdr_ptr++) { |
| 443 | u64 offset; |
| 444 | if (phdr_ptr->p_type != PT_NOTE) |
| 445 | continue; |
| 446 | offset = phdr_ptr->p_offset; |
| 447 | rc = read_from_oldmem(notes_buf, phdr_ptr->p_memsz, &offset, 0); |
| 448 | if (rc < 0) |
| 449 | return rc; |
| 450 | notes_buf += phdr_ptr->p_memsz; |
| 451 | } |
| 452 | |
| 453 | return 0; |
| 454 | } |
| 455 | |
| 456 | /* Merges all the PT_NOTE headers into one. */ |
| 457 | static int __init merge_note_headers_elf64(char *elfptr, size_t *elfsz, |
| 458 | char **notes_buf, size_t *notes_sz) |
| 459 | { |
| 460 | int i, nr_ptnote=0, rc=0; |
| 461 | char *tmp; |
| 462 | Elf64_Ehdr *ehdr_ptr; |
| 463 | Elf64_Phdr phdr; |
| 464 | u64 phdr_sz = 0, note_off; |
| 465 | |
| 466 | ehdr_ptr = (Elf64_Ehdr *)elfptr; |
| 467 | |
| 468 | rc = update_note_header_size_elf64(ehdr_ptr); |
| 469 | if (rc < 0) |
| 470 | return rc; |
| 471 | |
| 472 | rc = get_note_number_and_size_elf64(ehdr_ptr, &nr_ptnote, &phdr_sz); |
| 473 | if (rc < 0) |
| 474 | return rc; |
| 475 | |
| 476 | *notes_sz = roundup(phdr_sz, PAGE_SIZE); |
HATAYAMA Daisuke | 8308697 | 2013-07-03 15:02:23 -0700 | [diff] [blame] | 477 | *notes_buf = alloc_elfnotes_buf(*notes_sz); |
HATAYAMA Daisuke | 087350c | 2013-07-03 15:02:19 -0700 | [diff] [blame] | 478 | if (!*notes_buf) |
| 479 | return -ENOMEM; |
| 480 | |
| 481 | rc = copy_notes_elf64(ehdr_ptr, *notes_buf); |
| 482 | if (rc < 0) |
| 483 | return rc; |
| 484 | |
Vivek Goyal | 666bfdd | 2005-06-25 14:58:21 -0700 | [diff] [blame] | 485 | /* Prepare merged PT_NOTE program header. */ |
| 486 | phdr.p_type = PT_NOTE; |
| 487 | phdr.p_flags = 0; |
| 488 | note_off = sizeof(Elf64_Ehdr) + |
| 489 | (ehdr_ptr->e_phnum - nr_ptnote +1) * sizeof(Elf64_Phdr); |
HATAYAMA Daisuke | 087350c | 2013-07-03 15:02:19 -0700 | [diff] [blame] | 490 | phdr.p_offset = roundup(note_off, PAGE_SIZE); |
Vivek Goyal | 666bfdd | 2005-06-25 14:58:21 -0700 | [diff] [blame] | 491 | phdr.p_vaddr = phdr.p_paddr = 0; |
| 492 | phdr.p_filesz = phdr.p_memsz = phdr_sz; |
| 493 | phdr.p_align = 0; |
| 494 | |
| 495 | /* Add merged PT_NOTE program header*/ |
| 496 | tmp = elfptr + sizeof(Elf64_Ehdr); |
| 497 | memcpy(tmp, &phdr, sizeof(phdr)); |
| 498 | tmp += sizeof(phdr); |
| 499 | |
| 500 | /* Remove unwanted PT_NOTE program headers. */ |
| 501 | i = (nr_ptnote - 1) * sizeof(Elf64_Phdr); |
| 502 | *elfsz = *elfsz - i; |
| 503 | memmove(tmp, tmp+i, ((*elfsz)-sizeof(Elf64_Ehdr)-sizeof(Elf64_Phdr))); |
HATAYAMA Daisuke | f2bdacd | 2013-07-03 15:02:14 -0700 | [diff] [blame] | 504 | memset(elfptr + *elfsz, 0, i); |
| 505 | *elfsz = roundup(*elfsz, PAGE_SIZE); |
Vivek Goyal | 666bfdd | 2005-06-25 14:58:21 -0700 | [diff] [blame] | 506 | |
| 507 | /* Modify e_phnum to reflect merged headers. */ |
| 508 | ehdr_ptr->e_phnum = ehdr_ptr->e_phnum - nr_ptnote + 1; |
| 509 | |
| 510 | return 0; |
| 511 | } |
| 512 | |
HATAYAMA Daisuke | 087350c | 2013-07-03 15:02:19 -0700 | [diff] [blame] | 513 | /** |
| 514 | * update_note_header_size_elf32 - update p_memsz member of each PT_NOTE entry |
| 515 | * |
| 516 | * @ehdr_ptr: ELF header |
| 517 | * |
| 518 | * This function updates p_memsz member of each PT_NOTE entry in the |
| 519 | * program header table pointed to by @ehdr_ptr to real size of ELF |
| 520 | * note segment. |
| 521 | */ |
| 522 | static int __init update_note_header_size_elf32(const Elf32_Ehdr *ehdr_ptr) |
Vivek Goyal | 72658e9 | 2005-06-25 14:58:22 -0700 | [diff] [blame] | 523 | { |
HATAYAMA Daisuke | 087350c | 2013-07-03 15:02:19 -0700 | [diff] [blame] | 524 | int i, rc=0; |
| 525 | Elf32_Phdr *phdr_ptr; |
Vivek Goyal | 72658e9 | 2005-06-25 14:58:22 -0700 | [diff] [blame] | 526 | Elf32_Nhdr *nhdr_ptr; |
Vivek Goyal | 72658e9 | 2005-06-25 14:58:22 -0700 | [diff] [blame] | 527 | |
HATAYAMA Daisuke | 087350c | 2013-07-03 15:02:19 -0700 | [diff] [blame] | 528 | phdr_ptr = (Elf32_Phdr *)(ehdr_ptr + 1); |
Vivek Goyal | 72658e9 | 2005-06-25 14:58:22 -0700 | [diff] [blame] | 529 | for (i = 0; i < ehdr_ptr->e_phnum; i++, phdr_ptr++) { |
Vivek Goyal | 72658e9 | 2005-06-25 14:58:22 -0700 | [diff] [blame] | 530 | void *notes_section; |
Vivek Goyal | 72658e9 | 2005-06-25 14:58:22 -0700 | [diff] [blame] | 531 | u64 offset, max_sz, sz, real_sz = 0; |
| 532 | if (phdr_ptr->p_type != PT_NOTE) |
| 533 | continue; |
Vivek Goyal | 72658e9 | 2005-06-25 14:58:22 -0700 | [diff] [blame] | 534 | max_sz = phdr_ptr->p_memsz; |
| 535 | offset = phdr_ptr->p_offset; |
| 536 | notes_section = kmalloc(max_sz, GFP_KERNEL); |
| 537 | if (!notes_section) |
| 538 | return -ENOMEM; |
| 539 | rc = read_from_oldmem(notes_section, max_sz, &offset, 0); |
| 540 | if (rc < 0) { |
| 541 | kfree(notes_section); |
| 542 | return rc; |
| 543 | } |
| 544 | nhdr_ptr = notes_section; |
HATAYAMA Daisuke | 087350c | 2013-07-03 15:02:19 -0700 | [diff] [blame] | 545 | while (real_sz < max_sz) { |
Vivek Goyal | 72658e9 | 2005-06-25 14:58:22 -0700 | [diff] [blame] | 546 | if (nhdr_ptr->n_namesz == 0) |
| 547 | break; |
| 548 | sz = sizeof(Elf32_Nhdr) + |
| 549 | ((nhdr_ptr->n_namesz + 3) & ~3) + |
| 550 | ((nhdr_ptr->n_descsz + 3) & ~3); |
| 551 | real_sz += sz; |
| 552 | nhdr_ptr = (Elf32_Nhdr*)((char*)nhdr_ptr + sz); |
| 553 | } |
Vivek Goyal | 72658e9 | 2005-06-25 14:58:22 -0700 | [diff] [blame] | 554 | kfree(notes_section); |
HATAYAMA Daisuke | 087350c | 2013-07-03 15:02:19 -0700 | [diff] [blame] | 555 | phdr_ptr->p_memsz = real_sz; |
Vivek Goyal | 72658e9 | 2005-06-25 14:58:22 -0700 | [diff] [blame] | 556 | } |
| 557 | |
HATAYAMA Daisuke | 087350c | 2013-07-03 15:02:19 -0700 | [diff] [blame] | 558 | return 0; |
| 559 | } |
| 560 | |
| 561 | /** |
| 562 | * get_note_number_and_size_elf32 - get the number of PT_NOTE program |
| 563 | * headers and sum of real size of their ELF note segment headers and |
| 564 | * data. |
| 565 | * |
| 566 | * @ehdr_ptr: ELF header |
| 567 | * @nr_ptnote: buffer for the number of PT_NOTE program headers |
| 568 | * @sz_ptnote: buffer for size of unique PT_NOTE program header |
| 569 | * |
| 570 | * This function is used to merge multiple PT_NOTE program headers |
| 571 | * into a unique single one. The resulting unique entry will have |
| 572 | * @sz_ptnote in its phdr->p_mem. |
| 573 | * |
| 574 | * It is assumed that program headers with PT_NOTE type pointed to by |
| 575 | * @ehdr_ptr has already been updated by update_note_header_size_elf32 |
| 576 | * and each of PT_NOTE program headers has actual ELF note segment |
| 577 | * size in its p_memsz member. |
| 578 | */ |
| 579 | static int __init get_note_number_and_size_elf32(const Elf32_Ehdr *ehdr_ptr, |
| 580 | int *nr_ptnote, u64 *sz_ptnote) |
| 581 | { |
| 582 | int i; |
| 583 | Elf32_Phdr *phdr_ptr; |
| 584 | |
| 585 | *nr_ptnote = *sz_ptnote = 0; |
| 586 | |
| 587 | phdr_ptr = (Elf32_Phdr *)(ehdr_ptr + 1); |
| 588 | for (i = 0; i < ehdr_ptr->e_phnum; i++, phdr_ptr++) { |
| 589 | if (phdr_ptr->p_type != PT_NOTE) |
| 590 | continue; |
| 591 | *nr_ptnote += 1; |
| 592 | *sz_ptnote += phdr_ptr->p_memsz; |
| 593 | } |
| 594 | |
| 595 | return 0; |
| 596 | } |
| 597 | |
| 598 | /** |
| 599 | * copy_notes_elf32 - copy ELF note segments in a given buffer |
| 600 | * |
| 601 | * @ehdr_ptr: ELF header |
| 602 | * @notes_buf: buffer into which ELF note segments are copied |
| 603 | * |
| 604 | * This function is used to copy ELF note segment in the 1st kernel |
| 605 | * into the buffer @notes_buf in the 2nd kernel. It is assumed that |
| 606 | * size of the buffer @notes_buf is equal to or larger than sum of the |
| 607 | * real ELF note segment headers and data. |
| 608 | * |
| 609 | * It is assumed that program headers with PT_NOTE type pointed to by |
| 610 | * @ehdr_ptr has already been updated by update_note_header_size_elf32 |
| 611 | * and each of PT_NOTE program headers has actual ELF note segment |
| 612 | * size in its p_memsz member. |
| 613 | */ |
| 614 | static int __init copy_notes_elf32(const Elf32_Ehdr *ehdr_ptr, char *notes_buf) |
| 615 | { |
| 616 | int i, rc=0; |
| 617 | Elf32_Phdr *phdr_ptr; |
| 618 | |
| 619 | phdr_ptr = (Elf32_Phdr*)(ehdr_ptr + 1); |
| 620 | |
| 621 | for (i = 0; i < ehdr_ptr->e_phnum; i++, phdr_ptr++) { |
| 622 | u64 offset; |
| 623 | if (phdr_ptr->p_type != PT_NOTE) |
| 624 | continue; |
| 625 | offset = phdr_ptr->p_offset; |
| 626 | rc = read_from_oldmem(notes_buf, phdr_ptr->p_memsz, &offset, 0); |
| 627 | if (rc < 0) |
| 628 | return rc; |
| 629 | notes_buf += phdr_ptr->p_memsz; |
| 630 | } |
| 631 | |
| 632 | return 0; |
| 633 | } |
| 634 | |
| 635 | /* Merges all the PT_NOTE headers into one. */ |
| 636 | static int __init merge_note_headers_elf32(char *elfptr, size_t *elfsz, |
| 637 | char **notes_buf, size_t *notes_sz) |
| 638 | { |
| 639 | int i, nr_ptnote=0, rc=0; |
| 640 | char *tmp; |
| 641 | Elf32_Ehdr *ehdr_ptr; |
| 642 | Elf32_Phdr phdr; |
| 643 | u64 phdr_sz = 0, note_off; |
| 644 | |
| 645 | ehdr_ptr = (Elf32_Ehdr *)elfptr; |
| 646 | |
| 647 | rc = update_note_header_size_elf32(ehdr_ptr); |
| 648 | if (rc < 0) |
| 649 | return rc; |
| 650 | |
| 651 | rc = get_note_number_and_size_elf32(ehdr_ptr, &nr_ptnote, &phdr_sz); |
| 652 | if (rc < 0) |
| 653 | return rc; |
| 654 | |
| 655 | *notes_sz = roundup(phdr_sz, PAGE_SIZE); |
HATAYAMA Daisuke | 8308697 | 2013-07-03 15:02:23 -0700 | [diff] [blame] | 656 | *notes_buf = alloc_elfnotes_buf(*notes_sz); |
HATAYAMA Daisuke | 087350c | 2013-07-03 15:02:19 -0700 | [diff] [blame] | 657 | if (!*notes_buf) |
| 658 | return -ENOMEM; |
| 659 | |
| 660 | rc = copy_notes_elf32(ehdr_ptr, *notes_buf); |
| 661 | if (rc < 0) |
| 662 | return rc; |
| 663 | |
Vivek Goyal | 72658e9 | 2005-06-25 14:58:22 -0700 | [diff] [blame] | 664 | /* Prepare merged PT_NOTE program header. */ |
| 665 | phdr.p_type = PT_NOTE; |
| 666 | phdr.p_flags = 0; |
| 667 | note_off = sizeof(Elf32_Ehdr) + |
| 668 | (ehdr_ptr->e_phnum - nr_ptnote +1) * sizeof(Elf32_Phdr); |
HATAYAMA Daisuke | 087350c | 2013-07-03 15:02:19 -0700 | [diff] [blame] | 669 | phdr.p_offset = roundup(note_off, PAGE_SIZE); |
Vivek Goyal | 72658e9 | 2005-06-25 14:58:22 -0700 | [diff] [blame] | 670 | phdr.p_vaddr = phdr.p_paddr = 0; |
| 671 | phdr.p_filesz = phdr.p_memsz = phdr_sz; |
| 672 | phdr.p_align = 0; |
| 673 | |
| 674 | /* Add merged PT_NOTE program header*/ |
| 675 | tmp = elfptr + sizeof(Elf32_Ehdr); |
| 676 | memcpy(tmp, &phdr, sizeof(phdr)); |
| 677 | tmp += sizeof(phdr); |
| 678 | |
| 679 | /* Remove unwanted PT_NOTE program headers. */ |
| 680 | i = (nr_ptnote - 1) * sizeof(Elf32_Phdr); |
| 681 | *elfsz = *elfsz - i; |
| 682 | memmove(tmp, tmp+i, ((*elfsz)-sizeof(Elf32_Ehdr)-sizeof(Elf32_Phdr))); |
HATAYAMA Daisuke | f2bdacd | 2013-07-03 15:02:14 -0700 | [diff] [blame] | 683 | memset(elfptr + *elfsz, 0, i); |
| 684 | *elfsz = roundup(*elfsz, PAGE_SIZE); |
Vivek Goyal | 72658e9 | 2005-06-25 14:58:22 -0700 | [diff] [blame] | 685 | |
| 686 | /* Modify e_phnum to reflect merged headers. */ |
| 687 | ehdr_ptr->e_phnum = ehdr_ptr->e_phnum - nr_ptnote + 1; |
| 688 | |
| 689 | return 0; |
| 690 | } |
| 691 | |
Vivek Goyal | 666bfdd | 2005-06-25 14:58:21 -0700 | [diff] [blame] | 692 | /* Add memory chunks represented by program headers to vmcore list. Also update |
| 693 | * the new offset fields of exported program headers. */ |
| 694 | static int __init process_ptload_program_headers_elf64(char *elfptr, |
| 695 | size_t elfsz, |
HATAYAMA Daisuke | 087350c | 2013-07-03 15:02:19 -0700 | [diff] [blame] | 696 | size_t elfnotes_sz, |
Vivek Goyal | 666bfdd | 2005-06-25 14:58:21 -0700 | [diff] [blame] | 697 | struct list_head *vc_list) |
| 698 | { |
| 699 | int i; |
| 700 | Elf64_Ehdr *ehdr_ptr; |
| 701 | Elf64_Phdr *phdr_ptr; |
| 702 | loff_t vmcore_off; |
| 703 | struct vmcore *new; |
| 704 | |
| 705 | ehdr_ptr = (Elf64_Ehdr *)elfptr; |
| 706 | phdr_ptr = (Elf64_Phdr*)(elfptr + sizeof(Elf64_Ehdr)); /* PT_NOTE hdr */ |
| 707 | |
HATAYAMA Daisuke | 087350c | 2013-07-03 15:02:19 -0700 | [diff] [blame] | 708 | /* Skip Elf header, program headers and Elf note segment. */ |
| 709 | vmcore_off = elfsz + elfnotes_sz; |
Vivek Goyal | 666bfdd | 2005-06-25 14:58:21 -0700 | [diff] [blame] | 710 | |
| 711 | for (i = 0; i < ehdr_ptr->e_phnum; i++, phdr_ptr++) { |
HATAYAMA Daisuke | 7f614cd | 2013-07-03 15:02:15 -0700 | [diff] [blame] | 712 | u64 paddr, start, end, size; |
| 713 | |
Vivek Goyal | 666bfdd | 2005-06-25 14:58:21 -0700 | [diff] [blame] | 714 | if (phdr_ptr->p_type != PT_LOAD) |
| 715 | continue; |
| 716 | |
HATAYAMA Daisuke | 7f614cd | 2013-07-03 15:02:15 -0700 | [diff] [blame] | 717 | paddr = phdr_ptr->p_offset; |
| 718 | start = rounddown(paddr, PAGE_SIZE); |
| 719 | end = roundup(paddr + phdr_ptr->p_memsz, PAGE_SIZE); |
| 720 | size = end - start; |
| 721 | |
Vivek Goyal | 666bfdd | 2005-06-25 14:58:21 -0700 | [diff] [blame] | 722 | /* Add this contiguous chunk of memory to vmcore list.*/ |
| 723 | new = get_new_element(); |
| 724 | if (!new) |
| 725 | return -ENOMEM; |
HATAYAMA Daisuke | 7f614cd | 2013-07-03 15:02:15 -0700 | [diff] [blame] | 726 | new->paddr = start; |
| 727 | new->size = size; |
Vivek Goyal | 666bfdd | 2005-06-25 14:58:21 -0700 | [diff] [blame] | 728 | list_add_tail(&new->list, vc_list); |
| 729 | |
| 730 | /* Update the program header offset. */ |
HATAYAMA Daisuke | 7f614cd | 2013-07-03 15:02:15 -0700 | [diff] [blame] | 731 | phdr_ptr->p_offset = vmcore_off + (paddr - start); |
| 732 | vmcore_off = vmcore_off + size; |
Vivek Goyal | 666bfdd | 2005-06-25 14:58:21 -0700 | [diff] [blame] | 733 | } |
| 734 | return 0; |
| 735 | } |
| 736 | |
Vivek Goyal | 72658e9 | 2005-06-25 14:58:22 -0700 | [diff] [blame] | 737 | static int __init process_ptload_program_headers_elf32(char *elfptr, |
| 738 | size_t elfsz, |
HATAYAMA Daisuke | 087350c | 2013-07-03 15:02:19 -0700 | [diff] [blame] | 739 | size_t elfnotes_sz, |
Vivek Goyal | 72658e9 | 2005-06-25 14:58:22 -0700 | [diff] [blame] | 740 | struct list_head *vc_list) |
| 741 | { |
| 742 | int i; |
| 743 | Elf32_Ehdr *ehdr_ptr; |
| 744 | Elf32_Phdr *phdr_ptr; |
| 745 | loff_t vmcore_off; |
| 746 | struct vmcore *new; |
| 747 | |
| 748 | ehdr_ptr = (Elf32_Ehdr *)elfptr; |
| 749 | phdr_ptr = (Elf32_Phdr*)(elfptr + sizeof(Elf32_Ehdr)); /* PT_NOTE hdr */ |
| 750 | |
HATAYAMA Daisuke | 087350c | 2013-07-03 15:02:19 -0700 | [diff] [blame] | 751 | /* Skip Elf header, program headers and Elf note segment. */ |
| 752 | vmcore_off = elfsz + elfnotes_sz; |
Vivek Goyal | 72658e9 | 2005-06-25 14:58:22 -0700 | [diff] [blame] | 753 | |
| 754 | for (i = 0; i < ehdr_ptr->e_phnum; i++, phdr_ptr++) { |
HATAYAMA Daisuke | 7f614cd | 2013-07-03 15:02:15 -0700 | [diff] [blame] | 755 | u64 paddr, start, end, size; |
| 756 | |
Vivek Goyal | 72658e9 | 2005-06-25 14:58:22 -0700 | [diff] [blame] | 757 | if (phdr_ptr->p_type != PT_LOAD) |
| 758 | continue; |
| 759 | |
HATAYAMA Daisuke | 7f614cd | 2013-07-03 15:02:15 -0700 | [diff] [blame] | 760 | paddr = phdr_ptr->p_offset; |
| 761 | start = rounddown(paddr, PAGE_SIZE); |
| 762 | end = roundup(paddr + phdr_ptr->p_memsz, PAGE_SIZE); |
| 763 | size = end - start; |
| 764 | |
Vivek Goyal | 72658e9 | 2005-06-25 14:58:22 -0700 | [diff] [blame] | 765 | /* Add this contiguous chunk of memory to vmcore list.*/ |
| 766 | new = get_new_element(); |
| 767 | if (!new) |
| 768 | return -ENOMEM; |
HATAYAMA Daisuke | 7f614cd | 2013-07-03 15:02:15 -0700 | [diff] [blame] | 769 | new->paddr = start; |
| 770 | new->size = size; |
Vivek Goyal | 72658e9 | 2005-06-25 14:58:22 -0700 | [diff] [blame] | 771 | list_add_tail(&new->list, vc_list); |
| 772 | |
| 773 | /* Update the program header offset */ |
HATAYAMA Daisuke | 7f614cd | 2013-07-03 15:02:15 -0700 | [diff] [blame] | 774 | phdr_ptr->p_offset = vmcore_off + (paddr - start); |
| 775 | vmcore_off = vmcore_off + size; |
Vivek Goyal | 72658e9 | 2005-06-25 14:58:22 -0700 | [diff] [blame] | 776 | } |
| 777 | return 0; |
| 778 | } |
| 779 | |
Vivek Goyal | 666bfdd | 2005-06-25 14:58:21 -0700 | [diff] [blame] | 780 | /* Sets offset fields of vmcore elements. */ |
HATAYAMA Daisuke | 087350c | 2013-07-03 15:02:19 -0700 | [diff] [blame] | 781 | static void __init set_vmcore_list_offsets(size_t elfsz, size_t elfnotes_sz, |
HATAYAMA Daisuke | f2bdacd | 2013-07-03 15:02:14 -0700 | [diff] [blame] | 782 | struct list_head *vc_list) |
Vivek Goyal | 666bfdd | 2005-06-25 14:58:21 -0700 | [diff] [blame] | 783 | { |
| 784 | loff_t vmcore_off; |
Vivek Goyal | 666bfdd | 2005-06-25 14:58:21 -0700 | [diff] [blame] | 785 | struct vmcore *m; |
| 786 | |
HATAYAMA Daisuke | 087350c | 2013-07-03 15:02:19 -0700 | [diff] [blame] | 787 | /* Skip Elf header, program headers and Elf note segment. */ |
| 788 | vmcore_off = elfsz + elfnotes_sz; |
Vivek Goyal | 666bfdd | 2005-06-25 14:58:21 -0700 | [diff] [blame] | 789 | |
| 790 | list_for_each_entry(m, vc_list, list) { |
| 791 | m->offset = vmcore_off; |
| 792 | vmcore_off += m->size; |
| 793 | } |
| 794 | } |
| 795 | |
HATAYAMA Daisuke | f2bdacd | 2013-07-03 15:02:14 -0700 | [diff] [blame] | 796 | static void free_elfcorebuf(void) |
Vivek Goyal | 72658e9 | 2005-06-25 14:58:22 -0700 | [diff] [blame] | 797 | { |
HATAYAMA Daisuke | f2bdacd | 2013-07-03 15:02:14 -0700 | [diff] [blame] | 798 | free_pages((unsigned long)elfcorebuf, get_order(elfcorebuf_sz_orig)); |
| 799 | elfcorebuf = NULL; |
HATAYAMA Daisuke | 087350c | 2013-07-03 15:02:19 -0700 | [diff] [blame] | 800 | vfree(elfnotes_buf); |
| 801 | elfnotes_buf = NULL; |
Vivek Goyal | 72658e9 | 2005-06-25 14:58:22 -0700 | [diff] [blame] | 802 | } |
| 803 | |
Vivek Goyal | 666bfdd | 2005-06-25 14:58:21 -0700 | [diff] [blame] | 804 | static int __init parse_crash_elf64_headers(void) |
| 805 | { |
| 806 | int rc=0; |
| 807 | Elf64_Ehdr ehdr; |
| 808 | u64 addr; |
| 809 | |
| 810 | addr = elfcorehdr_addr; |
| 811 | |
| 812 | /* Read Elf header */ |
| 813 | rc = read_from_oldmem((char*)&ehdr, sizeof(Elf64_Ehdr), &addr, 0); |
| 814 | if (rc < 0) |
| 815 | return rc; |
| 816 | |
| 817 | /* Do some basic Verification. */ |
| 818 | if (memcmp(ehdr.e_ident, ELFMAG, SELFMAG) != 0 || |
| 819 | (ehdr.e_type != ET_CORE) || |
Mika Westerberg | 9833c39 | 2010-11-19 09:29:24 +0100 | [diff] [blame] | 820 | !vmcore_elf64_check_arch(&ehdr) || |
Vivek Goyal | 666bfdd | 2005-06-25 14:58:21 -0700 | [diff] [blame] | 821 | ehdr.e_ident[EI_CLASS] != ELFCLASS64 || |
| 822 | ehdr.e_ident[EI_VERSION] != EV_CURRENT || |
| 823 | ehdr.e_version != EV_CURRENT || |
| 824 | ehdr.e_ehsize != sizeof(Elf64_Ehdr) || |
| 825 | ehdr.e_phentsize != sizeof(Elf64_Phdr) || |
| 826 | ehdr.e_phnum == 0) { |
Andrew Morton | 87ebdc0 | 2013-02-27 17:03:16 -0800 | [diff] [blame] | 827 | pr_warn("Warning: Core image elf header is not sane\n"); |
Vivek Goyal | 666bfdd | 2005-06-25 14:58:21 -0700 | [diff] [blame] | 828 | return -EINVAL; |
| 829 | } |
| 830 | |
| 831 | /* Read in all elf headers. */ |
HATAYAMA Daisuke | f2bdacd | 2013-07-03 15:02:14 -0700 | [diff] [blame] | 832 | elfcorebuf_sz_orig = sizeof(Elf64_Ehdr) + |
| 833 | ehdr.e_phnum * sizeof(Elf64_Phdr); |
| 834 | elfcorebuf_sz = elfcorebuf_sz_orig; |
| 835 | elfcorebuf = (void *)__get_free_pages(GFP_KERNEL | __GFP_ZERO, |
| 836 | get_order(elfcorebuf_sz_orig)); |
Vivek Goyal | 666bfdd | 2005-06-25 14:58:21 -0700 | [diff] [blame] | 837 | if (!elfcorebuf) |
| 838 | return -ENOMEM; |
| 839 | addr = elfcorehdr_addr; |
HATAYAMA Daisuke | f2bdacd | 2013-07-03 15:02:14 -0700 | [diff] [blame] | 840 | rc = read_from_oldmem(elfcorebuf, elfcorebuf_sz_orig, &addr, 0); |
| 841 | if (rc < 0) |
| 842 | goto fail; |
Vivek Goyal | 666bfdd | 2005-06-25 14:58:21 -0700 | [diff] [blame] | 843 | |
| 844 | /* Merge all PT_NOTE headers into one. */ |
HATAYAMA Daisuke | 087350c | 2013-07-03 15:02:19 -0700 | [diff] [blame] | 845 | rc = merge_note_headers_elf64(elfcorebuf, &elfcorebuf_sz, |
| 846 | &elfnotes_buf, &elfnotes_sz); |
HATAYAMA Daisuke | f2bdacd | 2013-07-03 15:02:14 -0700 | [diff] [blame] | 847 | if (rc) |
| 848 | goto fail; |
Vivek Goyal | 666bfdd | 2005-06-25 14:58:21 -0700 | [diff] [blame] | 849 | rc = process_ptload_program_headers_elf64(elfcorebuf, elfcorebuf_sz, |
HATAYAMA Daisuke | 087350c | 2013-07-03 15:02:19 -0700 | [diff] [blame] | 850 | elfnotes_sz, &vmcore_list); |
HATAYAMA Daisuke | f2bdacd | 2013-07-03 15:02:14 -0700 | [diff] [blame] | 851 | if (rc) |
| 852 | goto fail; |
HATAYAMA Daisuke | 087350c | 2013-07-03 15:02:19 -0700 | [diff] [blame] | 853 | set_vmcore_list_offsets(elfcorebuf_sz, elfnotes_sz, &vmcore_list); |
Vivek Goyal | 666bfdd | 2005-06-25 14:58:21 -0700 | [diff] [blame] | 854 | return 0; |
HATAYAMA Daisuke | f2bdacd | 2013-07-03 15:02:14 -0700 | [diff] [blame] | 855 | fail: |
| 856 | free_elfcorebuf(); |
| 857 | return rc; |
Vivek Goyal | 666bfdd | 2005-06-25 14:58:21 -0700 | [diff] [blame] | 858 | } |
| 859 | |
Vivek Goyal | 72658e9 | 2005-06-25 14:58:22 -0700 | [diff] [blame] | 860 | static int __init parse_crash_elf32_headers(void) |
| 861 | { |
| 862 | int rc=0; |
| 863 | Elf32_Ehdr ehdr; |
| 864 | u64 addr; |
| 865 | |
| 866 | addr = elfcorehdr_addr; |
| 867 | |
| 868 | /* Read Elf header */ |
| 869 | rc = read_from_oldmem((char*)&ehdr, sizeof(Elf32_Ehdr), &addr, 0); |
| 870 | if (rc < 0) |
| 871 | return rc; |
| 872 | |
| 873 | /* Do some basic Verification. */ |
| 874 | if (memcmp(ehdr.e_ident, ELFMAG, SELFMAG) != 0 || |
| 875 | (ehdr.e_type != ET_CORE) || |
| 876 | !elf_check_arch(&ehdr) || |
| 877 | ehdr.e_ident[EI_CLASS] != ELFCLASS32|| |
| 878 | ehdr.e_ident[EI_VERSION] != EV_CURRENT || |
| 879 | ehdr.e_version != EV_CURRENT || |
| 880 | ehdr.e_ehsize != sizeof(Elf32_Ehdr) || |
| 881 | ehdr.e_phentsize != sizeof(Elf32_Phdr) || |
| 882 | ehdr.e_phnum == 0) { |
Andrew Morton | 87ebdc0 | 2013-02-27 17:03:16 -0800 | [diff] [blame] | 883 | pr_warn("Warning: Core image elf header is not sane\n"); |
Vivek Goyal | 72658e9 | 2005-06-25 14:58:22 -0700 | [diff] [blame] | 884 | return -EINVAL; |
| 885 | } |
| 886 | |
| 887 | /* Read in all elf headers. */ |
HATAYAMA Daisuke | f2bdacd | 2013-07-03 15:02:14 -0700 | [diff] [blame] | 888 | elfcorebuf_sz_orig = sizeof(Elf32_Ehdr) + ehdr.e_phnum * sizeof(Elf32_Phdr); |
| 889 | elfcorebuf_sz = elfcorebuf_sz_orig; |
| 890 | elfcorebuf = (void *)__get_free_pages(GFP_KERNEL | __GFP_ZERO, |
| 891 | get_order(elfcorebuf_sz_orig)); |
Vivek Goyal | 72658e9 | 2005-06-25 14:58:22 -0700 | [diff] [blame] | 892 | if (!elfcorebuf) |
| 893 | return -ENOMEM; |
| 894 | addr = elfcorehdr_addr; |
HATAYAMA Daisuke | f2bdacd | 2013-07-03 15:02:14 -0700 | [diff] [blame] | 895 | rc = read_from_oldmem(elfcorebuf, elfcorebuf_sz_orig, &addr, 0); |
| 896 | if (rc < 0) |
| 897 | goto fail; |
Vivek Goyal | 72658e9 | 2005-06-25 14:58:22 -0700 | [diff] [blame] | 898 | |
| 899 | /* Merge all PT_NOTE headers into one. */ |
HATAYAMA Daisuke | 087350c | 2013-07-03 15:02:19 -0700 | [diff] [blame] | 900 | rc = merge_note_headers_elf32(elfcorebuf, &elfcorebuf_sz, |
| 901 | &elfnotes_buf, &elfnotes_sz); |
HATAYAMA Daisuke | f2bdacd | 2013-07-03 15:02:14 -0700 | [diff] [blame] | 902 | if (rc) |
| 903 | goto fail; |
Vivek Goyal | 72658e9 | 2005-06-25 14:58:22 -0700 | [diff] [blame] | 904 | rc = process_ptload_program_headers_elf32(elfcorebuf, elfcorebuf_sz, |
HATAYAMA Daisuke | 087350c | 2013-07-03 15:02:19 -0700 | [diff] [blame] | 905 | elfnotes_sz, &vmcore_list); |
HATAYAMA Daisuke | f2bdacd | 2013-07-03 15:02:14 -0700 | [diff] [blame] | 906 | if (rc) |
| 907 | goto fail; |
HATAYAMA Daisuke | 087350c | 2013-07-03 15:02:19 -0700 | [diff] [blame] | 908 | set_vmcore_list_offsets(elfcorebuf_sz, elfnotes_sz, &vmcore_list); |
Vivek Goyal | 72658e9 | 2005-06-25 14:58:22 -0700 | [diff] [blame] | 909 | return 0; |
HATAYAMA Daisuke | f2bdacd | 2013-07-03 15:02:14 -0700 | [diff] [blame] | 910 | fail: |
| 911 | free_elfcorebuf(); |
| 912 | return rc; |
Vivek Goyal | 72658e9 | 2005-06-25 14:58:22 -0700 | [diff] [blame] | 913 | } |
| 914 | |
Vivek Goyal | 666bfdd | 2005-06-25 14:58:21 -0700 | [diff] [blame] | 915 | static int __init parse_crash_elf_headers(void) |
| 916 | { |
| 917 | unsigned char e_ident[EI_NIDENT]; |
| 918 | u64 addr; |
| 919 | int rc=0; |
| 920 | |
| 921 | addr = elfcorehdr_addr; |
| 922 | rc = read_from_oldmem(e_ident, EI_NIDENT, &addr, 0); |
| 923 | if (rc < 0) |
| 924 | return rc; |
| 925 | if (memcmp(e_ident, ELFMAG, SELFMAG) != 0) { |
Andrew Morton | 87ebdc0 | 2013-02-27 17:03:16 -0800 | [diff] [blame] | 926 | pr_warn("Warning: Core image elf header not found\n"); |
Vivek Goyal | 666bfdd | 2005-06-25 14:58:21 -0700 | [diff] [blame] | 927 | return -EINVAL; |
| 928 | } |
| 929 | |
| 930 | if (e_ident[EI_CLASS] == ELFCLASS64) { |
| 931 | rc = parse_crash_elf64_headers(); |
| 932 | if (rc) |
| 933 | return rc; |
Vivek Goyal | 72658e9 | 2005-06-25 14:58:22 -0700 | [diff] [blame] | 934 | } else if (e_ident[EI_CLASS] == ELFCLASS32) { |
| 935 | rc = parse_crash_elf32_headers(); |
| 936 | if (rc) |
| 937 | return rc; |
Vivek Goyal | 666bfdd | 2005-06-25 14:58:21 -0700 | [diff] [blame] | 938 | } else { |
Andrew Morton | 87ebdc0 | 2013-02-27 17:03:16 -0800 | [diff] [blame] | 939 | pr_warn("Warning: Core image elf header is not sane\n"); |
Vivek Goyal | 666bfdd | 2005-06-25 14:58:21 -0700 | [diff] [blame] | 940 | return -EINVAL; |
| 941 | } |
HATAYAMA Daisuke | 591ff71 | 2013-07-03 15:02:22 -0700 | [diff] [blame] | 942 | |
| 943 | /* Determine vmcore size. */ |
| 944 | vmcore_size = get_vmcore_size(elfcorebuf_sz, elfnotes_sz, |
| 945 | &vmcore_list); |
| 946 | |
Vivek Goyal | 666bfdd | 2005-06-25 14:58:21 -0700 | [diff] [blame] | 947 | return 0; |
| 948 | } |
| 949 | |
| 950 | /* Init function for vmcore module. */ |
| 951 | static int __init vmcore_init(void) |
| 952 | { |
| 953 | int rc = 0; |
| 954 | |
| 955 | /* If elfcorehdr= has been passed in cmdline, then capture the dump.*/ |
Simon Horman | 85a0ee3 | 2008-10-18 20:28:29 -0700 | [diff] [blame] | 956 | if (!(is_vmcore_usable())) |
Vivek Goyal | 666bfdd | 2005-06-25 14:58:21 -0700 | [diff] [blame] | 957 | return rc; |
| 958 | rc = parse_crash_elf_headers(); |
| 959 | if (rc) { |
Andrew Morton | 87ebdc0 | 2013-02-27 17:03:16 -0800 | [diff] [blame] | 960 | pr_warn("Kdump: vmcore not initialized\n"); |
Vivek Goyal | 666bfdd | 2005-06-25 14:58:21 -0700 | [diff] [blame] | 961 | return rc; |
| 962 | } |
| 963 | |
Alexey Dobriyan | 5aa140c | 2008-10-06 14:36:31 +0400 | [diff] [blame] | 964 | proc_vmcore = proc_create("vmcore", S_IRUSR, NULL, &proc_vmcore_operations); |
Vivek Goyal | 666bfdd | 2005-06-25 14:58:21 -0700 | [diff] [blame] | 965 | if (proc_vmcore) |
| 966 | proc_vmcore->size = vmcore_size; |
| 967 | return 0; |
| 968 | } |
| 969 | module_init(vmcore_init) |
Mahesh Salgaonkar | 16257393 | 2012-02-16 01:15:00 +0000 | [diff] [blame] | 970 | |
| 971 | /* Cleanup function for vmcore module. */ |
| 972 | void vmcore_cleanup(void) |
| 973 | { |
| 974 | struct list_head *pos, *next; |
| 975 | |
| 976 | if (proc_vmcore) { |
David Howells | a8ca16e | 2013-04-12 17:27:28 +0100 | [diff] [blame] | 977 | proc_remove(proc_vmcore); |
Mahesh Salgaonkar | 16257393 | 2012-02-16 01:15:00 +0000 | [diff] [blame] | 978 | proc_vmcore = NULL; |
| 979 | } |
| 980 | |
| 981 | /* clear the vmcore list. */ |
| 982 | list_for_each_safe(pos, next, &vmcore_list) { |
| 983 | struct vmcore *m; |
| 984 | |
| 985 | m = list_entry(pos, struct vmcore, list); |
| 986 | list_del(&m->list); |
| 987 | kfree(m); |
| 988 | } |
HATAYAMA Daisuke | f2bdacd | 2013-07-03 15:02:14 -0700 | [diff] [blame] | 989 | free_elfcorebuf(); |
Mahesh Salgaonkar | 16257393 | 2012-02-16 01:15:00 +0000 | [diff] [blame] | 990 | } |
| 991 | EXPORT_SYMBOL_GPL(vmcore_cleanup); |