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v3.15
 
  1/*
  2 * misc.c
  3 *
  4 * This is a collection of several routines from gzip-1.0.3
  5 * adapted for Linux.
 
 
  6 *
  7 * malloc by Hannu Savolainen 1993 and Matthias Urlichs 1994
  8 * puts by Nick Holloway 1993, better puts by Martin Mares 1995
  9 * High loaded stuff by Hans Lermen & Werner Almesberger, Feb. 1996
 10 */
 11
 12#include "misc.h"
 
 
 13#include "../string.h"
 14
 15/* WARNING!!
 16 * This code is compiled with -fPIC and it is relocated dynamically
 17 * at run time, but no relocation processing is performed.
 18 * This means that it is not safe to place pointers in static structures.
 19 */
 20
 21/*
 22 * Getting to provable safe in place decompression is hard.
 23 * Worst case behaviours need to be analyzed.
 24 * Background information:
 25 *
 26 * The file layout is:
 27 *    magic[2]
 28 *    method[1]
 29 *    flags[1]
 30 *    timestamp[4]
 31 *    extraflags[1]
 32 *    os[1]
 33 *    compressed data blocks[N]
 34 *    crc[4] orig_len[4]
 35 *
 36 * resulting in 18 bytes of non compressed data overhead.
 37 *
 38 * Files divided into blocks
 39 * 1 bit (last block flag)
 40 * 2 bits (block type)
 41 *
 42 * 1 block occurs every 32K -1 bytes or when there 50% compression
 43 * has been achieved. The smallest block type encoding is always used.
 44 *
 45 * stored:
 46 *    32 bits length in bytes.
 47 *
 48 * fixed:
 49 *    magic fixed tree.
 50 *    symbols.
 51 *
 52 * dynamic:
 53 *    dynamic tree encoding.
 54 *    symbols.
 55 *
 56 *
 57 * The buffer for decompression in place is the length of the
 58 * uncompressed data, plus a small amount extra to keep the algorithm safe.
 59 * The compressed data is placed at the end of the buffer.  The output
 60 * pointer is placed at the start of the buffer and the input pointer
 61 * is placed where the compressed data starts.  Problems will occur
 62 * when the output pointer overruns the input pointer.
 63 *
 64 * The output pointer can only overrun the input pointer if the input
 65 * pointer is moving faster than the output pointer.  A condition only
 66 * triggered by data whose compressed form is larger than the uncompressed
 67 * form.
 68 *
 69 * The worst case at the block level is a growth of the compressed data
 70 * of 5 bytes per 32767 bytes.
 71 *
 72 * The worst case internal to a compressed block is very hard to figure.
 73 * The worst case can at least be boundined by having one bit that represents
 74 * 32764 bytes and then all of the rest of the bytes representing the very
 75 * very last byte.
 76 *
 77 * All of which is enough to compute an amount of extra data that is required
 78 * to be safe.  To avoid problems at the block level allocating 5 extra bytes
 79 * per 32767 bytes of data is sufficient.  To avoind problems internal to a
 80 * block adding an extra 32767 bytes (the worst case uncompressed block size)
 81 * is sufficient, to ensure that in the worst case the decompressed data for
 82 * block will stop the byte before the compressed data for a block begins.
 83 * To avoid problems with the compressed data's meta information an extra 18
 84 * bytes are needed.  Leading to the formula:
 85 *
 86 * extra_bytes = (uncompressed_size >> 12) + 32768 + 18 + decompressor_size.
 87 *
 88 * Adding 8 bytes per 32K is a bit excessive but much easier to calculate.
 89 * Adding 32768 instead of 32767 just makes for round numbers.
 90 * Adding the decompressor_size is necessary as it musht live after all
 91 * of the data as well.  Last I measured the decompressor is about 14K.
 92 * 10K of actual data and 4K of bss.
 93 *
 94 */
 95
 96/*
 97 * gzip declarations
 98 */
 99#define STATIC		static
100
101#undef memcpy
 
102
103/*
104 * Use a normal definition of memset() from string.c. There are already
105 * included header files which expect a definition of memset() and by
106 * the time we define memset macro, it is too late.
107 */
108#undef memset
109#define memzero(s, n)	memset((s), 0, (n))
110
111
112static void error(char *m);
 
 
113
114/*
115 * This is set up by the setup-routine at boot-time
116 */
117struct boot_params *real_mode;		/* Pointer to real-mode data */
 
 
118
119memptr free_mem_ptr;
120memptr free_mem_end_ptr;
121
122static char *vidmem;
123static int vidport;
124static int lines, cols;
 
 
 
125
126#ifdef CONFIG_KERNEL_GZIP
127#include "../../../../lib/decompress_inflate.c"
128#endif
129
130#ifdef CONFIG_KERNEL_BZIP2
131#include "../../../../lib/decompress_bunzip2.c"
132#endif
133
134#ifdef CONFIG_KERNEL_LZMA
135#include "../../../../lib/decompress_unlzma.c"
136#endif
137
138#ifdef CONFIG_KERNEL_XZ
139#include "../../../../lib/decompress_unxz.c"
140#endif
141
142#ifdef CONFIG_KERNEL_LZO
143#include "../../../../lib/decompress_unlzo.c"
144#endif
145
146#ifdef CONFIG_KERNEL_LZ4
147#include "../../../../lib/decompress_unlz4.c"
148#endif
149
 
 
 
 
 
 
 
 
150static void scroll(void)
151{
152	int i;
153
154	memcpy(vidmem, vidmem + cols * 2, (lines - 1) * cols * 2);
155	for (i = (lines - 1) * cols * 2; i < lines * cols * 2; i += 2)
156		vidmem[i] = ' ';
157}
158
159#define XMTRDY          0x20
160
161#define TXR             0       /*  Transmit register (WRITE) */
162#define LSR             5       /*  Line Status               */
163static void serial_putchar(int ch)
164{
165	unsigned timeout = 0xffff;
166
167	while ((inb(early_serial_base + LSR) & XMTRDY) == 0 && --timeout)
168		cpu_relax();
169
170	outb(ch, early_serial_base + TXR);
171}
172
173void __putstr(const char *s)
174{
175	int x, y, pos;
176	char c;
177
178	if (early_serial_base) {
179		const char *str = s;
180		while (*str) {
181			if (*str == '\n')
182				serial_putchar('\r');
183			serial_putchar(*str++);
184		}
185	}
186
187	if (real_mode->screen_info.orig_video_mode == 0 &&
188	    lines == 0 && cols == 0)
189		return;
190
191	x = real_mode->screen_info.orig_x;
192	y = real_mode->screen_info.orig_y;
193
194	while ((c = *s++) != '\0') {
195		if (c == '\n') {
196			x = 0;
197			if (++y >= lines) {
198				scroll();
199				y--;
200			}
201		} else {
202			vidmem[(x + cols * y) * 2] = c;
203			if (++x >= cols) {
204				x = 0;
205				if (++y >= lines) {
206					scroll();
207					y--;
208				}
209			}
210		}
211	}
212
213	real_mode->screen_info.orig_x = x;
214	real_mode->screen_info.orig_y = y;
215
216	pos = (x + cols * y) * 2;	/* Update cursor position */
217	outb(14, vidport);
218	outb(0xff & (pos >> 9), vidport+1);
219	outb(15, vidport);
220	outb(0xff & (pos >> 1), vidport+1);
221}
222
223static void error(char *x)
224{
225	error_putstr("\n\n");
226	error_putstr(x);
227	error_putstr("\n\n -- System halted");
 
 
228
229	while (1)
230		asm("hlt");
 
 
 
 
 
231}
232
233#if CONFIG_X86_NEED_RELOCS
234static void handle_relocations(void *output, unsigned long output_len)
 
235{
236	int *reloc;
237	unsigned long delta, map, ptr;
238	unsigned long min_addr = (unsigned long)output;
239	unsigned long max_addr = min_addr + output_len;
240
241	/*
242	 * Calculate the delta between where vmlinux was linked to load
243	 * and where it was actually loaded.
244	 */
245	delta = min_addr - LOAD_PHYSICAL_ADDR;
246	if (!delta) {
247		debug_putstr("No relocation needed... ");
248		return;
249	}
250	debug_putstr("Performing relocations... ");
251
252	/*
253	 * The kernel contains a table of relocation addresses. Those
254	 * addresses have the final load address of the kernel in virtual
255	 * memory. We are currently working in the self map. So we need to
256	 * create an adjustment for kernel memory addresses to the self map.
257	 * This will involve subtracting out the base address of the kernel.
258	 */
259	map = delta - __START_KERNEL_map;
260
261	/*
 
 
 
 
 
 
 
 
 
 
 
 
 
 
262	 * Process relocations: 32 bit relocations first then 64 bit after.
263	 * Two sets of binary relocations are added to the end of the kernel
264	 * before compression. Each relocation table entry is the kernel
265	 * address of the location which needs to be updated stored as a
266	 * 32-bit value which is sign extended to 64 bits.
267	 *
268	 * Format is:
269	 *
270	 * kernel bits...
271	 * 0 - zero terminator for 64 bit relocations
272	 * 64 bit relocation repeated
 
 
273	 * 0 - zero terminator for 32 bit relocations
274	 * 32 bit relocation repeated
275	 *
276	 * So we work backwards from the end of the decompressed image.
277	 */
278	for (reloc = output + output_len - sizeof(*reloc); *reloc; reloc--) {
279		int extended = *reloc;
280		extended += map;
281
282		ptr = (unsigned long)extended;
283		if (ptr < min_addr || ptr > max_addr)
284			error("32-bit relocation outside of kernel!\n");
285
286		*(uint32_t *)ptr += delta;
287	}
288#ifdef CONFIG_X86_64
 
 
 
 
 
 
 
 
 
 
289	for (reloc--; *reloc; reloc--) {
290		long extended = *reloc;
291		extended += map;
292
293		ptr = (unsigned long)extended;
294		if (ptr < min_addr || ptr > max_addr)
295			error("64-bit relocation outside of kernel!\n");
296
297		*(uint64_t *)ptr += delta;
298	}
299#endif
300}
301#else
302static inline void handle_relocations(void *output, unsigned long output_len)
 
303{ }
304#endif
305
306static void parse_elf(void *output)
307{
308#ifdef CONFIG_X86_64
309	Elf64_Ehdr ehdr;
310	Elf64_Phdr *phdrs, *phdr;
311#else
312	Elf32_Ehdr ehdr;
313	Elf32_Phdr *phdrs, *phdr;
314#endif
315	void *dest;
316	int i;
317
318	memcpy(&ehdr, output, sizeof(ehdr));
319	if (ehdr.e_ident[EI_MAG0] != ELFMAG0 ||
320	   ehdr.e_ident[EI_MAG1] != ELFMAG1 ||
321	   ehdr.e_ident[EI_MAG2] != ELFMAG2 ||
322	   ehdr.e_ident[EI_MAG3] != ELFMAG3) {
323		error("Kernel is not a valid ELF file");
324		return;
325	}
326
327	debug_putstr("Parsing ELF... ");
328
329	phdrs = malloc(sizeof(*phdrs) * ehdr.e_phnum);
330	if (!phdrs)
331		error("Failed to allocate space for phdrs");
332
333	memcpy(phdrs, output + ehdr.e_phoff, sizeof(*phdrs) * ehdr.e_phnum);
334
335	for (i = 0; i < ehdr.e_phnum; i++) {
336		phdr = &phdrs[i];
337
338		switch (phdr->p_type) {
339		case PT_LOAD:
 
 
 
 
340#ifdef CONFIG_RELOCATABLE
341			dest = output;
342			dest += (phdr->p_paddr - LOAD_PHYSICAL_ADDR);
343#else
344			dest = (void *)(phdr->p_paddr);
345#endif
346			memcpy(dest,
347			       output + phdr->p_offset,
348			       phdr->p_filesz);
349			break;
350		default: /* Ignore other PT_* */ break;
351		}
352	}
353
354	free(phdrs);
355}
356
357asmlinkage __visible void *decompress_kernel(void *rmode, memptr heap,
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
358				  unsigned char *input_data,
359				  unsigned long input_len,
360				  unsigned char *output,
361				  unsigned long output_len)
362{
363	real_mode = rmode;
 
 
364
365	sanitize_boot_params(real_mode);
 
366
367	if (real_mode->screen_info.orig_video_mode == 7) {
 
 
 
 
 
368		vidmem = (char *) 0xb0000;
369		vidport = 0x3b4;
370	} else {
371		vidmem = (char *) 0xb8000;
372		vidport = 0x3d4;
373	}
374
375	lines = real_mode->screen_info.orig_video_lines;
376	cols = real_mode->screen_info.orig_video_cols;
 
 
 
 
 
 
 
 
 
 
377
378	console_init();
379	debug_putstr("early console in decompress_kernel\n");
 
 
 
 
 
 
 
 
380
381	free_mem_ptr     = heap;	/* Heap */
382	free_mem_end_ptr = heap + BOOT_HEAP_SIZE;
383
384	output = choose_kernel_location(input_data, input_len,
385					output, output_len);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
386
387	/* Validate memory location choices. */
388	if ((unsigned long)output & (MIN_KERNEL_ALIGN - 1))
389		error("Destination address inappropriately aligned");
 
 
390#ifdef CONFIG_X86_64
391	if (heap > 0x3fffffffffffUL)
392		error("Destination address too large");
 
 
393#else
394	if (heap > ((-__PAGE_OFFSET-(128<<20)-1) & 0x7fffffff))
395		error("Destination address too large");
396#endif
397#ifndef CONFIG_RELOCATABLE
398	if ((unsigned long)output != LOAD_PHYSICAL_ADDR)
399		error("Wrong destination address");
400#endif
401
402	debug_putstr("\nDecompressing Linux... ");
403	decompress(input_data, input_len, NULL, NULL, output, NULL, error);
 
404	parse_elf(output);
405	handle_relocations(output, output_len);
406	debug_putstr("done.\nBooting the kernel.\n");
 
 
 
 
407	return output;
 
 
 
 
 
408}
v6.2
  1// SPDX-License-Identifier: GPL-2.0
  2/*
  3 * misc.c
  4 *
  5 * This is a collection of several routines used to extract the kernel
  6 * which includes KASLR relocation, decompression, ELF parsing, and
  7 * relocation processing. Additionally included are the screen and serial
  8 * output functions and related debugging support functions.
  9 *
 10 * malloc by Hannu Savolainen 1993 and Matthias Urlichs 1994
 11 * puts by Nick Holloway 1993, better puts by Martin Mares 1995
 12 * High loaded stuff by Hans Lermen & Werner Almesberger, Feb. 1996
 13 */
 14
 15#include "misc.h"
 16#include "error.h"
 17#include "pgtable.h"
 18#include "../string.h"
 19#include "../voffset.h"
 20#include <asm/bootparam_utils.h>
 
 
 
 
 21
 22/*
 23 * WARNING!!
 24 * This code is compiled with -fPIC and it is relocated dynamically at
 25 * run time, but no relocation processing is performed. This means that
 26 * it is not safe to place pointers in static structures.
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 27 */
 28
 29/* Macros used by the included decompressor code below. */
 
 
 30#define STATIC		static
 31/* Define an externally visible malloc()/free(). */
 32#define MALLOC_VISIBLE
 33#include <linux/decompress/mm.h>
 34
 35/*
 36 * Provide definitions of memzero and memmove as some of the decompressors will
 37 * try to define their own functions if these are not defined as macros.
 
 38 */
 
 39#define memzero(s, n)	memset((s), 0, (n))
 40#ifndef memmove
 41#define memmove		memmove
 42/* Functions used by the included decompressor code below. */
 43void *memmove(void *dest, const void *src, size_t n);
 44#endif
 45
 46/*
 47 * This is set up by the setup-routine at boot-time
 48 */
 49struct boot_params *boot_params;
 50
 51struct port_io_ops pio_ops;
 52
 53memptr free_mem_ptr;
 54memptr free_mem_end_ptr;
 55
 56static char *vidmem;
 57static int vidport;
 58
 59/* These might be accessed before .bss is cleared, so use .data instead. */
 60static int lines __section(".data");
 61static int cols __section(".data");
 62
 63#ifdef CONFIG_KERNEL_GZIP
 64#include "../../../../lib/decompress_inflate.c"
 65#endif
 66
 67#ifdef CONFIG_KERNEL_BZIP2
 68#include "../../../../lib/decompress_bunzip2.c"
 69#endif
 70
 71#ifdef CONFIG_KERNEL_LZMA
 72#include "../../../../lib/decompress_unlzma.c"
 73#endif
 74
 75#ifdef CONFIG_KERNEL_XZ
 76#include "../../../../lib/decompress_unxz.c"
 77#endif
 78
 79#ifdef CONFIG_KERNEL_LZO
 80#include "../../../../lib/decompress_unlzo.c"
 81#endif
 82
 83#ifdef CONFIG_KERNEL_LZ4
 84#include "../../../../lib/decompress_unlz4.c"
 85#endif
 86
 87#ifdef CONFIG_KERNEL_ZSTD
 88#include "../../../../lib/decompress_unzstd.c"
 89#endif
 90/*
 91 * NOTE: When adding a new decompressor, please update the analysis in
 92 * ../header.S.
 93 */
 94
 95static void scroll(void)
 96{
 97	int i;
 98
 99	memmove(vidmem, vidmem + cols * 2, (lines - 1) * cols * 2);
100	for (i = (lines - 1) * cols * 2; i < lines * cols * 2; i += 2)
101		vidmem[i] = ' ';
102}
103
104#define XMTRDY          0x20
105
106#define TXR             0       /*  Transmit register (WRITE) */
107#define LSR             5       /*  Line Status               */
108static void serial_putchar(int ch)
109{
110	unsigned timeout = 0xffff;
111
112	while ((inb(early_serial_base + LSR) & XMTRDY) == 0 && --timeout)
113		cpu_relax();
114
115	outb(ch, early_serial_base + TXR);
116}
117
118void __putstr(const char *s)
119{
120	int x, y, pos;
121	char c;
122
123	if (early_serial_base) {
124		const char *str = s;
125		while (*str) {
126			if (*str == '\n')
127				serial_putchar('\r');
128			serial_putchar(*str++);
129		}
130	}
131
132	if (lines == 0 || cols == 0)
 
133		return;
134
135	x = boot_params->screen_info.orig_x;
136	y = boot_params->screen_info.orig_y;
137
138	while ((c = *s++) != '\0') {
139		if (c == '\n') {
140			x = 0;
141			if (++y >= lines) {
142				scroll();
143				y--;
144			}
145		} else {
146			vidmem[(x + cols * y) * 2] = c;
147			if (++x >= cols) {
148				x = 0;
149				if (++y >= lines) {
150					scroll();
151					y--;
152				}
153			}
154		}
155	}
156
157	boot_params->screen_info.orig_x = x;
158	boot_params->screen_info.orig_y = y;
159
160	pos = (x + cols * y) * 2;	/* Update cursor position */
161	outb(14, vidport);
162	outb(0xff & (pos >> 9), vidport+1);
163	outb(15, vidport);
164	outb(0xff & (pos >> 1), vidport+1);
165}
166
167void __puthex(unsigned long value)
168{
169	char alpha[2] = "0";
170	int bits;
171
172	for (bits = sizeof(value) * 8 - 4; bits >= 0; bits -= 4) {
173		unsigned long digit = (value >> bits) & 0xf;
174
175		if (digit < 0xA)
176			alpha[0] = '0' + digit;
177		else
178			alpha[0] = 'a' + (digit - 0xA);
179
180		__putstr(alpha);
181	}
182}
183
184#ifdef CONFIG_X86_NEED_RELOCS
185static void handle_relocations(void *output, unsigned long output_len,
186			       unsigned long virt_addr)
187{
188	int *reloc;
189	unsigned long delta, map, ptr;
190	unsigned long min_addr = (unsigned long)output;
191	unsigned long max_addr = min_addr + (VO___bss_start - VO__text);
192
193	/*
194	 * Calculate the delta between where vmlinux was linked to load
195	 * and where it was actually loaded.
196	 */
197	delta = min_addr - LOAD_PHYSICAL_ADDR;
 
 
 
 
 
198
199	/*
200	 * The kernel contains a table of relocation addresses. Those
201	 * addresses have the final load address of the kernel in virtual
202	 * memory. We are currently working in the self map. So we need to
203	 * create an adjustment for kernel memory addresses to the self map.
204	 * This will involve subtracting out the base address of the kernel.
205	 */
206	map = delta - __START_KERNEL_map;
207
208	/*
209	 * 32-bit always performs relocations. 64-bit relocations are only
210	 * needed if KASLR has chosen a different starting address offset
211	 * from __START_KERNEL_map.
212	 */
213	if (IS_ENABLED(CONFIG_X86_64))
214		delta = virt_addr - LOAD_PHYSICAL_ADDR;
215
216	if (!delta) {
217		debug_putstr("No relocation needed... ");
218		return;
219	}
220	debug_putstr("Performing relocations... ");
221
222	/*
223	 * Process relocations: 32 bit relocations first then 64 bit after.
224	 * Three sets of binary relocations are added to the end of the kernel
225	 * before compression. Each relocation table entry is the kernel
226	 * address of the location which needs to be updated stored as a
227	 * 32-bit value which is sign extended to 64 bits.
228	 *
229	 * Format is:
230	 *
231	 * kernel bits...
232	 * 0 - zero terminator for 64 bit relocations
233	 * 64 bit relocation repeated
234	 * 0 - zero terminator for inverse 32 bit relocations
235	 * 32 bit inverse relocation repeated
236	 * 0 - zero terminator for 32 bit relocations
237	 * 32 bit relocation repeated
238	 *
239	 * So we work backwards from the end of the decompressed image.
240	 */
241	for (reloc = output + output_len - sizeof(*reloc); *reloc; reloc--) {
242		long extended = *reloc;
243		extended += map;
244
245		ptr = (unsigned long)extended;
246		if (ptr < min_addr || ptr > max_addr)
247			error("32-bit relocation outside of kernel!\n");
248
249		*(uint32_t *)ptr += delta;
250	}
251#ifdef CONFIG_X86_64
252	while (*--reloc) {
253		long extended = *reloc;
254		extended += map;
255
256		ptr = (unsigned long)extended;
257		if (ptr < min_addr || ptr > max_addr)
258			error("inverse 32-bit relocation outside of kernel!\n");
259
260		*(int32_t *)ptr -= delta;
261	}
262	for (reloc--; *reloc; reloc--) {
263		long extended = *reloc;
264		extended += map;
265
266		ptr = (unsigned long)extended;
267		if (ptr < min_addr || ptr > max_addr)
268			error("64-bit relocation outside of kernel!\n");
269
270		*(uint64_t *)ptr += delta;
271	}
272#endif
273}
274#else
275static inline void handle_relocations(void *output, unsigned long output_len,
276				      unsigned long virt_addr)
277{ }
278#endif
279
280static void parse_elf(void *output)
281{
282#ifdef CONFIG_X86_64
283	Elf64_Ehdr ehdr;
284	Elf64_Phdr *phdrs, *phdr;
285#else
286	Elf32_Ehdr ehdr;
287	Elf32_Phdr *phdrs, *phdr;
288#endif
289	void *dest;
290	int i;
291
292	memcpy(&ehdr, output, sizeof(ehdr));
293	if (ehdr.e_ident[EI_MAG0] != ELFMAG0 ||
294	   ehdr.e_ident[EI_MAG1] != ELFMAG1 ||
295	   ehdr.e_ident[EI_MAG2] != ELFMAG2 ||
296	   ehdr.e_ident[EI_MAG3] != ELFMAG3) {
297		error("Kernel is not a valid ELF file");
298		return;
299	}
300
301	debug_putstr("Parsing ELF... ");
302
303	phdrs = malloc(sizeof(*phdrs) * ehdr.e_phnum);
304	if (!phdrs)
305		error("Failed to allocate space for phdrs");
306
307	memcpy(phdrs, output + ehdr.e_phoff, sizeof(*phdrs) * ehdr.e_phnum);
308
309	for (i = 0; i < ehdr.e_phnum; i++) {
310		phdr = &phdrs[i];
311
312		switch (phdr->p_type) {
313		case PT_LOAD:
314#ifdef CONFIG_X86_64
315			if ((phdr->p_align % 0x200000) != 0)
316				error("Alignment of LOAD segment isn't multiple of 2MB");
317#endif
318#ifdef CONFIG_RELOCATABLE
319			dest = output;
320			dest += (phdr->p_paddr - LOAD_PHYSICAL_ADDR);
321#else
322			dest = (void *)(phdr->p_paddr);
323#endif
324			memmove(dest, output + phdr->p_offset, phdr->p_filesz);
 
 
325			break;
326		default: /* Ignore other PT_* */ break;
327		}
328	}
329
330	free(phdrs);
331}
332
333/*
334 * The compressed kernel image (ZO), has been moved so that its position
335 * is against the end of the buffer used to hold the uncompressed kernel
336 * image (VO) and the execution environment (.bss, .brk), which makes sure
337 * there is room to do the in-place decompression. (See header.S for the
338 * calculations.)
339 *
340 *                             |-----compressed kernel image------|
341 *                             V                                  V
342 * 0                       extract_offset                      +INIT_SIZE
343 * |-----------|---------------|-------------------------|--------|
344 *             |               |                         |        |
345 *           VO__text      startup_32 of ZO          VO__end    ZO__end
346 *             ^                                         ^
347 *             |-------uncompressed kernel image---------|
348 *
349 */
350asmlinkage __visible void *extract_kernel(void *rmode, memptr heap,
351				  unsigned char *input_data,
352				  unsigned long input_len,
353				  unsigned char *output,
354				  unsigned long output_len)
355{
356	const unsigned long kernel_total_size = VO__end - VO__text;
357	unsigned long virt_addr = LOAD_PHYSICAL_ADDR;
358	unsigned long needed_size;
359
360	/* Retain x86 boot parameters pointer passed from startup_32/64. */
361	boot_params = rmode;
362
363	/* Clear flags intended for solely in-kernel use. */
364	boot_params->hdr.loadflags &= ~KASLR_FLAG;
365
366	sanitize_boot_params(boot_params);
367
368	if (boot_params->screen_info.orig_video_mode == 7) {
369		vidmem = (char *) 0xb0000;
370		vidport = 0x3b4;
371	} else {
372		vidmem = (char *) 0xb8000;
373		vidport = 0x3d4;
374	}
375
376	lines = boot_params->screen_info.orig_video_lines;
377	cols = boot_params->screen_info.orig_video_cols;
378
379	init_default_io_ops();
380
381	/*
382	 * Detect TDX guest environment.
383	 *
384	 * It has to be done before console_init() in order to use
385	 * paravirtualized port I/O operations if needed.
386	 */
387	early_tdx_detect();
388
389	console_init();
390
391	/*
392	 * Save RSDP address for later use. Have this after console_init()
393	 * so that early debugging output from the RSDP parsing code can be
394	 * collected.
395	 */
396	boot_params->acpi_rsdp_addr = get_rsdp_addr();
397
398	debug_putstr("early console in extract_kernel\n");
399
400	free_mem_ptr     = heap;	/* Heap */
401	free_mem_end_ptr = heap + BOOT_HEAP_SIZE;
402
403	/*
404	 * The memory hole needed for the kernel is the larger of either
405	 * the entire decompressed kernel plus relocation table, or the
406	 * entire decompressed kernel plus .bss and .brk sections.
407	 *
408	 * On X86_64, the memory is mapped with PMD pages. Round the
409	 * size up so that the full extent of PMD pages mapped is
410	 * included in the check against the valid memory table
411	 * entries. This ensures the full mapped area is usable RAM
412	 * and doesn't include any reserved areas.
413	 */
414	needed_size = max(output_len, kernel_total_size);
415#ifdef CONFIG_X86_64
416	needed_size = ALIGN(needed_size, MIN_KERNEL_ALIGN);
417#endif
418
419	/* Report initial kernel position details. */
420	debug_putaddr(input_data);
421	debug_putaddr(input_len);
422	debug_putaddr(output);
423	debug_putaddr(output_len);
424	debug_putaddr(kernel_total_size);
425	debug_putaddr(needed_size);
426
427#ifdef CONFIG_X86_64
428	/* Report address of 32-bit trampoline */
429	debug_putaddr(trampoline_32bit);
430#endif
431
432	choose_random_location((unsigned long)input_data, input_len,
433				(unsigned long *)&output,
434				needed_size,
435				&virt_addr);
436
437	/* Validate memory location choices. */
438	if ((unsigned long)output & (MIN_KERNEL_ALIGN - 1))
439		error("Destination physical address inappropriately aligned");
440	if (virt_addr & (MIN_KERNEL_ALIGN - 1))
441		error("Destination virtual address inappropriately aligned");
442#ifdef CONFIG_X86_64
443	if (heap > 0x3fffffffffffUL)
444		error("Destination address too large");
445	if (virt_addr + max(output_len, kernel_total_size) > KERNEL_IMAGE_SIZE)
446		error("Destination virtual address is beyond the kernel mapping area");
447#else
448	if (heap > ((-__PAGE_OFFSET-(128<<20)-1) & 0x7fffffff))
449		error("Destination address too large");
450#endif
451#ifndef CONFIG_RELOCATABLE
452	if (virt_addr != LOAD_PHYSICAL_ADDR)
453		error("Destination virtual address changed when not relocatable");
454#endif
455
456	debug_putstr("\nDecompressing Linux... ");
457	__decompress(input_data, input_len, NULL, NULL, output, output_len,
458			NULL, error);
459	parse_elf(output);
460	handle_relocations(output, output_len, virt_addr);
461	debug_putstr("done.\nBooting the kernel.\n");
462
463	/* Disable exception handling before booting the kernel */
464	cleanup_exception_handling();
465
466	return output;
467}
468
469void fortify_panic(const char *name)
470{
471	error("detected buffer overflow");
472}