Merge tag 'for-linus' of github.com:openrisc/linux
[linux-2.6-microblaze.git] / arch / x86 / kernel / kexec-bzimage64.c
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Kexec bzImage loader
4  *
5  * Copyright (C) 2014 Red Hat Inc.
6  * Authors:
7  *      Vivek Goyal <vgoyal@redhat.com>
8  */
9
10 #define pr_fmt(fmt)     "kexec-bzImage64: " fmt
11
12 #include <linux/string.h>
13 #include <linux/printk.h>
14 #include <linux/errno.h>
15 #include <linux/slab.h>
16 #include <linux/kexec.h>
17 #include <linux/kernel.h>
18 #include <linux/mm.h>
19 #include <linux/efi.h>
20 #include <linux/random.h>
21
22 #include <asm/bootparam.h>
23 #include <asm/setup.h>
24 #include <asm/crash.h>
25 #include <asm/efi.h>
26 #include <asm/e820/api.h>
27 #include <asm/kexec-bzimage64.h>
28
29 #define MAX_ELFCOREHDR_STR_LEN  30      /* elfcorehdr=0x<64bit-value> */
30
31 /*
32  * Defines lowest physical address for various segments. Not sure where
33  * exactly these limits came from. Current bzimage64 loader in kexec-tools
34  * uses these so I am retaining it. It can be changed over time as we gain
35  * more insight.
36  */
37 #define MIN_PURGATORY_ADDR      0x3000
38 #define MIN_BOOTPARAM_ADDR      0x3000
39 #define MIN_KERNEL_LOAD_ADDR    0x100000
40 #define MIN_INITRD_LOAD_ADDR    0x1000000
41
42 /*
43  * This is a place holder for all boot loader specific data structure which
44  * gets allocated in one call but gets freed much later during cleanup
45  * time. Right now there is only one field but it can grow as need be.
46  */
47 struct bzimage64_data {
48         /*
49          * Temporary buffer to hold bootparams buffer. This should be
50          * freed once the bootparam segment has been loaded.
51          */
52         void *bootparams_buf;
53 };
54
55 static int setup_initrd(struct boot_params *params,
56                 unsigned long initrd_load_addr, unsigned long initrd_len)
57 {
58         params->hdr.ramdisk_image = initrd_load_addr & 0xffffffffUL;
59         params->hdr.ramdisk_size = initrd_len & 0xffffffffUL;
60
61         params->ext_ramdisk_image = initrd_load_addr >> 32;
62         params->ext_ramdisk_size = initrd_len >> 32;
63
64         return 0;
65 }
66
67 static int setup_cmdline(struct kimage *image, struct boot_params *params,
68                          unsigned long bootparams_load_addr,
69                          unsigned long cmdline_offset, char *cmdline,
70                          unsigned long cmdline_len)
71 {
72         char *cmdline_ptr = ((char *)params) + cmdline_offset;
73         unsigned long cmdline_ptr_phys, len = 0;
74         uint32_t cmdline_low_32, cmdline_ext_32;
75
76         if (image->type == KEXEC_TYPE_CRASH) {
77                 len = sprintf(cmdline_ptr,
78                         "elfcorehdr=0x%lx ", image->elf_load_addr);
79         }
80         memcpy(cmdline_ptr + len, cmdline, cmdline_len);
81         cmdline_len += len;
82
83         cmdline_ptr[cmdline_len - 1] = '\0';
84
85         pr_debug("Final command line is: %s\n", cmdline_ptr);
86         cmdline_ptr_phys = bootparams_load_addr + cmdline_offset;
87         cmdline_low_32 = cmdline_ptr_phys & 0xffffffffUL;
88         cmdline_ext_32 = cmdline_ptr_phys >> 32;
89
90         params->hdr.cmd_line_ptr = cmdline_low_32;
91         if (cmdline_ext_32)
92                 params->ext_cmd_line_ptr = cmdline_ext_32;
93
94         return 0;
95 }
96
97 static int setup_e820_entries(struct boot_params *params)
98 {
99         unsigned int nr_e820_entries;
100
101         nr_e820_entries = e820_table_kexec->nr_entries;
102
103         /* TODO: Pass entries more than E820_MAX_ENTRIES_ZEROPAGE in bootparams setup data */
104         if (nr_e820_entries > E820_MAX_ENTRIES_ZEROPAGE)
105                 nr_e820_entries = E820_MAX_ENTRIES_ZEROPAGE;
106
107         params->e820_entries = nr_e820_entries;
108         memcpy(&params->e820_table, &e820_table_kexec->entries, nr_e820_entries*sizeof(struct e820_entry));
109
110         return 0;
111 }
112
113 enum { RNG_SEED_LENGTH = 32 };
114
115 static void
116 setup_rng_seed(struct boot_params *params, unsigned long params_load_addr,
117                unsigned int rng_seed_setup_data_offset)
118 {
119         struct setup_data *sd = (void *)params + rng_seed_setup_data_offset;
120         unsigned long setup_data_phys;
121
122         if (!rng_is_initialized())
123                 return;
124
125         sd->type = SETUP_RNG_SEED;
126         sd->len = RNG_SEED_LENGTH;
127         get_random_bytes(sd->data, RNG_SEED_LENGTH);
128         setup_data_phys = params_load_addr + rng_seed_setup_data_offset;
129         sd->next = params->hdr.setup_data;
130         params->hdr.setup_data = setup_data_phys;
131 }
132
133 #ifdef CONFIG_EFI
134 static int setup_efi_info_memmap(struct boot_params *params,
135                                   unsigned long params_load_addr,
136                                   unsigned int efi_map_offset,
137                                   unsigned int efi_map_sz)
138 {
139         void *efi_map = (void *)params + efi_map_offset;
140         unsigned long efi_map_phys_addr = params_load_addr + efi_map_offset;
141         struct efi_info *ei = &params->efi_info;
142
143         if (!efi_map_sz)
144                 return 0;
145
146         efi_runtime_map_copy(efi_map, efi_map_sz);
147
148         ei->efi_memmap = efi_map_phys_addr & 0xffffffff;
149         ei->efi_memmap_hi = efi_map_phys_addr >> 32;
150         ei->efi_memmap_size = efi_map_sz;
151
152         return 0;
153 }
154
155 static int
156 prepare_add_efi_setup_data(struct boot_params *params,
157                        unsigned long params_load_addr,
158                        unsigned int efi_setup_data_offset)
159 {
160         unsigned long setup_data_phys;
161         struct setup_data *sd = (void *)params + efi_setup_data_offset;
162         struct efi_setup_data *esd = (void *)sd + sizeof(struct setup_data);
163
164         esd->fw_vendor = efi_fw_vendor;
165         esd->tables = efi_config_table;
166         esd->smbios = efi.smbios;
167
168         sd->type = SETUP_EFI;
169         sd->len = sizeof(struct efi_setup_data);
170
171         /* Add setup data */
172         setup_data_phys = params_load_addr + efi_setup_data_offset;
173         sd->next = params->hdr.setup_data;
174         params->hdr.setup_data = setup_data_phys;
175
176         return 0;
177 }
178
179 static int
180 setup_efi_state(struct boot_params *params, unsigned long params_load_addr,
181                 unsigned int efi_map_offset, unsigned int efi_map_sz,
182                 unsigned int efi_setup_data_offset)
183 {
184         struct efi_info *current_ei = &boot_params.efi_info;
185         struct efi_info *ei = &params->efi_info;
186
187         if (!efi_enabled(EFI_RUNTIME_SERVICES))
188                 return 0;
189
190         if (!current_ei->efi_memmap_size)
191                 return 0;
192
193         params->secure_boot = boot_params.secure_boot;
194         ei->efi_loader_signature = current_ei->efi_loader_signature;
195         ei->efi_systab = current_ei->efi_systab;
196         ei->efi_systab_hi = current_ei->efi_systab_hi;
197
198         ei->efi_memdesc_version = current_ei->efi_memdesc_version;
199         ei->efi_memdesc_size = efi_get_runtime_map_desc_size();
200
201         setup_efi_info_memmap(params, params_load_addr, efi_map_offset,
202                               efi_map_sz);
203         prepare_add_efi_setup_data(params, params_load_addr,
204                                    efi_setup_data_offset);
205         return 0;
206 }
207 #endif /* CONFIG_EFI */
208
209 static void
210 setup_ima_state(const struct kimage *image, struct boot_params *params,
211                 unsigned long params_load_addr,
212                 unsigned int ima_setup_data_offset)
213 {
214 #ifdef CONFIG_IMA_KEXEC
215         struct setup_data *sd = (void *)params + ima_setup_data_offset;
216         unsigned long setup_data_phys;
217         struct ima_setup_data *ima;
218
219         if (!image->ima_buffer_size)
220                 return;
221
222         sd->type = SETUP_IMA;
223         sd->len = sizeof(*ima);
224
225         ima = (void *)sd + sizeof(struct setup_data);
226         ima->addr = image->ima_buffer_addr;
227         ima->size = image->ima_buffer_size;
228
229         /* Add setup data */
230         setup_data_phys = params_load_addr + ima_setup_data_offset;
231         sd->next = params->hdr.setup_data;
232         params->hdr.setup_data = setup_data_phys;
233 #endif /* CONFIG_IMA_KEXEC */
234 }
235
236 static int
237 setup_boot_parameters(struct kimage *image, struct boot_params *params,
238                       unsigned long params_load_addr,
239                       unsigned int efi_map_offset, unsigned int efi_map_sz,
240                       unsigned int setup_data_offset)
241 {
242         unsigned int nr_e820_entries;
243         unsigned long long mem_k, start, end;
244         int i, ret = 0;
245
246         /* Get subarch from existing bootparams */
247         params->hdr.hardware_subarch = boot_params.hdr.hardware_subarch;
248
249         /* Copying screen_info will do? */
250         memcpy(&params->screen_info, &screen_info, sizeof(struct screen_info));
251
252         /* Fill in memsize later */
253         params->screen_info.ext_mem_k = 0;
254         params->alt_mem_k = 0;
255
256         /* Always fill in RSDP: it is either 0 or a valid value */
257         params->acpi_rsdp_addr = boot_params.acpi_rsdp_addr;
258
259         /* Default APM info */
260         memset(&params->apm_bios_info, 0, sizeof(params->apm_bios_info));
261
262         /* Default drive info */
263         memset(&params->hd0_info, 0, sizeof(params->hd0_info));
264         memset(&params->hd1_info, 0, sizeof(params->hd1_info));
265
266         if (image->type == KEXEC_TYPE_CRASH) {
267                 ret = crash_setup_memmap_entries(image, params);
268                 if (ret)
269                         return ret;
270         } else
271                 setup_e820_entries(params);
272
273         nr_e820_entries = params->e820_entries;
274
275         for (i = 0; i < nr_e820_entries; i++) {
276                 if (params->e820_table[i].type != E820_TYPE_RAM)
277                         continue;
278                 start = params->e820_table[i].addr;
279                 end = params->e820_table[i].addr + params->e820_table[i].size - 1;
280
281                 if ((start <= 0x100000) && end > 0x100000) {
282                         mem_k = (end >> 10) - (0x100000 >> 10);
283                         params->screen_info.ext_mem_k = mem_k;
284                         params->alt_mem_k = mem_k;
285                         if (mem_k > 0xfc00)
286                                 params->screen_info.ext_mem_k = 0xfc00; /* 64M*/
287                         if (mem_k > 0xffffffff)
288                                 params->alt_mem_k = 0xffffffff;
289                 }
290         }
291
292 #ifdef CONFIG_EFI
293         /* Setup EFI state */
294         setup_efi_state(params, params_load_addr, efi_map_offset, efi_map_sz,
295                         setup_data_offset);
296         setup_data_offset += sizeof(struct setup_data) +
297                         sizeof(struct efi_setup_data);
298 #endif
299
300         if (IS_ENABLED(CONFIG_IMA_KEXEC)) {
301                 /* Setup IMA log buffer state */
302                 setup_ima_state(image, params, params_load_addr,
303                                 setup_data_offset);
304                 setup_data_offset += sizeof(struct setup_data) +
305                                      sizeof(struct ima_setup_data);
306         }
307
308         /* Setup RNG seed */
309         setup_rng_seed(params, params_load_addr, setup_data_offset);
310
311         /* Setup EDD info */
312         memcpy(params->eddbuf, boot_params.eddbuf,
313                                 EDDMAXNR * sizeof(struct edd_info));
314         params->eddbuf_entries = boot_params.eddbuf_entries;
315
316         memcpy(params->edd_mbr_sig_buffer, boot_params.edd_mbr_sig_buffer,
317                EDD_MBR_SIG_MAX * sizeof(unsigned int));
318
319         return ret;
320 }
321
322 static int bzImage64_probe(const char *buf, unsigned long len)
323 {
324         int ret = -ENOEXEC;
325         struct setup_header *header;
326
327         /* kernel should be at least two sectors long */
328         if (len < 2 * 512) {
329                 pr_err("File is too short to be a bzImage\n");
330                 return ret;
331         }
332
333         header = (struct setup_header *)(buf + offsetof(struct boot_params, hdr));
334         if (memcmp((char *)&header->header, "HdrS", 4) != 0) {
335                 pr_err("Not a bzImage\n");
336                 return ret;
337         }
338
339         if (header->boot_flag != 0xAA55) {
340                 pr_err("No x86 boot sector present\n");
341                 return ret;
342         }
343
344         if (header->version < 0x020C) {
345                 pr_err("Must be at least protocol version 2.12\n");
346                 return ret;
347         }
348
349         if (!(header->loadflags & LOADED_HIGH)) {
350                 pr_err("zImage not a bzImage\n");
351                 return ret;
352         }
353
354         if (!(header->xloadflags & XLF_KERNEL_64)) {
355                 pr_err("Not a bzImage64. XLF_KERNEL_64 is not set.\n");
356                 return ret;
357         }
358
359         if (!(header->xloadflags & XLF_CAN_BE_LOADED_ABOVE_4G)) {
360                 pr_err("XLF_CAN_BE_LOADED_ABOVE_4G is not set.\n");
361                 return ret;
362         }
363
364         /*
365          * Can't handle 32bit EFI as it does not allow loading kernel
366          * above 4G. This should be handled by 32bit bzImage loader
367          */
368         if (efi_enabled(EFI_RUNTIME_SERVICES) && !efi_enabled(EFI_64BIT)) {
369                 pr_debug("EFI is 32 bit. Can't load kernel above 4G.\n");
370                 return ret;
371         }
372
373         if (!(header->xloadflags & XLF_5LEVEL) && pgtable_l5_enabled()) {
374                 pr_err("bzImage cannot handle 5-level paging mode.\n");
375                 return ret;
376         }
377
378         /* I've got a bzImage */
379         pr_debug("It's a relocatable bzImage64\n");
380         ret = 0;
381
382         return ret;
383 }
384
385 static void *bzImage64_load(struct kimage *image, char *kernel,
386                             unsigned long kernel_len, char *initrd,
387                             unsigned long initrd_len, char *cmdline,
388                             unsigned long cmdline_len)
389 {
390
391         struct setup_header *header;
392         int setup_sects, kern16_size, ret = 0;
393         unsigned long setup_header_size, params_cmdline_sz;
394         struct boot_params *params;
395         unsigned long bootparam_load_addr, kernel_load_addr, initrd_load_addr;
396         struct bzimage64_data *ldata;
397         struct kexec_entry64_regs regs64;
398         void *stack;
399         unsigned int setup_hdr_offset = offsetof(struct boot_params, hdr);
400         unsigned int efi_map_offset, efi_map_sz, efi_setup_data_offset;
401         struct kexec_buf kbuf = { .image = image, .buf_max = ULONG_MAX,
402                                   .top_down = true };
403         struct kexec_buf pbuf = { .image = image, .buf_min = MIN_PURGATORY_ADDR,
404                                   .buf_max = ULONG_MAX, .top_down = true };
405
406         header = (struct setup_header *)(kernel + setup_hdr_offset);
407         setup_sects = header->setup_sects;
408         if (setup_sects == 0)
409                 setup_sects = 4;
410
411         kern16_size = (setup_sects + 1) * 512;
412         if (kernel_len < kern16_size) {
413                 pr_err("bzImage truncated\n");
414                 return ERR_PTR(-ENOEXEC);
415         }
416
417         if (cmdline_len > header->cmdline_size) {
418                 pr_err("Kernel command line too long\n");
419                 return ERR_PTR(-EINVAL);
420         }
421
422         /*
423          * In case of crash dump, we will append elfcorehdr=<addr> to
424          * command line. Make sure it does not overflow
425          */
426         if (cmdline_len + MAX_ELFCOREHDR_STR_LEN > header->cmdline_size) {
427                 pr_debug("Appending elfcorehdr=<addr> to command line exceeds maximum allowed length\n");
428                 return ERR_PTR(-EINVAL);
429         }
430
431         /* Allocate and load backup region */
432         if (image->type == KEXEC_TYPE_CRASH) {
433                 ret = crash_load_segments(image);
434                 if (ret)
435                         return ERR_PTR(ret);
436         }
437
438         /*
439          * Load purgatory. For 64bit entry point, purgatory  code can be
440          * anywhere.
441          */
442         ret = kexec_load_purgatory(image, &pbuf);
443         if (ret) {
444                 pr_err("Loading purgatory failed\n");
445                 return ERR_PTR(ret);
446         }
447
448         pr_debug("Loaded purgatory at 0x%lx\n", pbuf.mem);
449
450
451         /*
452          * Load Bootparams and cmdline and space for efi stuff.
453          *
454          * Allocate memory together for multiple data structures so
455          * that they all can go in single area/segment and we don't
456          * have to create separate segment for each. Keeps things
457          * little bit simple
458          */
459         efi_map_sz = efi_get_runtime_map_size();
460         params_cmdline_sz = sizeof(struct boot_params) + cmdline_len +
461                                 MAX_ELFCOREHDR_STR_LEN;
462         params_cmdline_sz = ALIGN(params_cmdline_sz, 16);
463         kbuf.bufsz = params_cmdline_sz + ALIGN(efi_map_sz, 16) +
464                                 sizeof(struct setup_data) +
465                                 sizeof(struct efi_setup_data) +
466                                 sizeof(struct setup_data) +
467                                 RNG_SEED_LENGTH;
468
469         if (IS_ENABLED(CONFIG_IMA_KEXEC))
470                 kbuf.bufsz += sizeof(struct setup_data) +
471                               sizeof(struct ima_setup_data);
472
473         params = kzalloc(kbuf.bufsz, GFP_KERNEL);
474         if (!params)
475                 return ERR_PTR(-ENOMEM);
476         efi_map_offset = params_cmdline_sz;
477         efi_setup_data_offset = efi_map_offset + ALIGN(efi_map_sz, 16);
478
479         /* Copy setup header onto bootparams. Documentation/x86/boot.rst */
480         setup_header_size = 0x0202 + kernel[0x0201] - setup_hdr_offset;
481
482         /* Is there a limit on setup header size? */
483         memcpy(&params->hdr, (kernel + setup_hdr_offset), setup_header_size);
484
485         kbuf.buffer = params;
486         kbuf.memsz = kbuf.bufsz;
487         kbuf.buf_align = 16;
488         kbuf.buf_min = MIN_BOOTPARAM_ADDR;
489         ret = kexec_add_buffer(&kbuf);
490         if (ret)
491                 goto out_free_params;
492         bootparam_load_addr = kbuf.mem;
493         pr_debug("Loaded boot_param, command line and misc at 0x%lx bufsz=0x%lx memsz=0x%lx\n",
494                  bootparam_load_addr, kbuf.bufsz, kbuf.bufsz);
495
496         /* Load kernel */
497         kbuf.buffer = kernel + kern16_size;
498         kbuf.bufsz =  kernel_len - kern16_size;
499         kbuf.memsz = PAGE_ALIGN(header->init_size);
500         kbuf.buf_align = header->kernel_alignment;
501         kbuf.buf_min = MIN_KERNEL_LOAD_ADDR;
502         kbuf.mem = KEXEC_BUF_MEM_UNKNOWN;
503         ret = kexec_add_buffer(&kbuf);
504         if (ret)
505                 goto out_free_params;
506         kernel_load_addr = kbuf.mem;
507
508         pr_debug("Loaded 64bit kernel at 0x%lx bufsz=0x%lx memsz=0x%lx\n",
509                  kernel_load_addr, kbuf.bufsz, kbuf.memsz);
510
511         /* Load initrd high */
512         if (initrd) {
513                 kbuf.buffer = initrd;
514                 kbuf.bufsz = kbuf.memsz = initrd_len;
515                 kbuf.buf_align = PAGE_SIZE;
516                 kbuf.buf_min = MIN_INITRD_LOAD_ADDR;
517                 kbuf.mem = KEXEC_BUF_MEM_UNKNOWN;
518                 ret = kexec_add_buffer(&kbuf);
519                 if (ret)
520                         goto out_free_params;
521                 initrd_load_addr = kbuf.mem;
522
523                 pr_debug("Loaded initrd at 0x%lx bufsz=0x%lx memsz=0x%lx\n",
524                                 initrd_load_addr, initrd_len, initrd_len);
525
526                 setup_initrd(params, initrd_load_addr, initrd_len);
527         }
528
529         setup_cmdline(image, params, bootparam_load_addr,
530                       sizeof(struct boot_params), cmdline, cmdline_len);
531
532         /* bootloader info. Do we need a separate ID for kexec kernel loader? */
533         params->hdr.type_of_loader = 0x0D << 4;
534         params->hdr.loadflags = 0;
535
536         /* Setup purgatory regs for entry */
537         ret = kexec_purgatory_get_set_symbol(image, "entry64_regs", &regs64,
538                                              sizeof(regs64), 1);
539         if (ret)
540                 goto out_free_params;
541
542         regs64.rbx = 0; /* Bootstrap Processor */
543         regs64.rsi = bootparam_load_addr;
544         regs64.rip = kernel_load_addr + 0x200;
545         stack = kexec_purgatory_get_symbol_addr(image, "stack_end");
546         if (IS_ERR(stack)) {
547                 pr_err("Could not find address of symbol stack_end\n");
548                 ret = -EINVAL;
549                 goto out_free_params;
550         }
551
552         regs64.rsp = (unsigned long)stack;
553         ret = kexec_purgatory_get_set_symbol(image, "entry64_regs", &regs64,
554                                              sizeof(regs64), 0);
555         if (ret)
556                 goto out_free_params;
557
558         ret = setup_boot_parameters(image, params, bootparam_load_addr,
559                                     efi_map_offset, efi_map_sz,
560                                     efi_setup_data_offset);
561         if (ret)
562                 goto out_free_params;
563
564         /* Allocate loader specific data */
565         ldata = kzalloc(sizeof(struct bzimage64_data), GFP_KERNEL);
566         if (!ldata) {
567                 ret = -ENOMEM;
568                 goto out_free_params;
569         }
570
571         /*
572          * Store pointer to params so that it could be freed after loading
573          * params segment has been loaded and contents have been copied
574          * somewhere else.
575          */
576         ldata->bootparams_buf = params;
577         return ldata;
578
579 out_free_params:
580         kfree(params);
581         return ERR_PTR(ret);
582 }
583
584 /* This cleanup function is called after various segments have been loaded */
585 static int bzImage64_cleanup(void *loader_data)
586 {
587         struct bzimage64_data *ldata = loader_data;
588
589         if (!ldata)
590                 return 0;
591
592         kfree(ldata->bootparams_buf);
593         ldata->bootparams_buf = NULL;
594
595         return 0;
596 }
597
598 const struct kexec_file_ops kexec_bzImage64_ops = {
599         .probe = bzImage64_probe,
600         .load = bzImage64_load,
601         .cleanup = bzImage64_cleanup,
602 #ifdef CONFIG_KEXEC_BZIMAGE_VERIFY_SIG
603         .verify_sig = kexec_kernel_verify_pe_sig,
604 #endif
605 };