Adding upstream version 4.19.249.upstream/4.19.249upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 429 insertions, 0 deletions

diff --git a/arch/x86/boot/compressed/misc.c b/arch/x86/boot/compressed/misc.c
new file mode 100644
index 000000000..0387d7a96
--- /dev/null
+++ b/arch/x86/boot/compressed/misc.c
@@ -0,0 +1,429 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * misc.c
+ *
+ * This is a collection of several routines used to extract the kernel
+ * which includes KASLR relocation, decompression, ELF parsing, and
+ * relocation processing. Additionally included are the screen and serial
+ * output functions and related debugging support functions.
+ *
+ * malloc by Hannu Savolainen 1993 and Matthias Urlichs 1994
+ * puts by Nick Holloway 1993, better puts by Martin Mares 1995
+ * High loaded stuff by Hans Lermen & Werner Almesberger, Feb. 1996
+ */
+
+#include "misc.h"
+#include "error.h"
+#include "pgtable.h"
+#include "../string.h"
+#include "../voffset.h"
+#include <asm/bootparam_utils.h>
+
+/*
+ * WARNING!!
+ * This code is compiled with -fPIC and it is relocated dynamically at
+ * run time, but no relocation processing is performed. This means that
+ * it is not safe to place pointers in static structures.
+ */
+
+/* Macros used by the included decompressor code below. */
+#define STATIC		static
+
+/*
+ * Use normal definitions of mem*() from string.c. There are already
+ * included header files which expect a definition of memset() and by
+ * the time we define memset macro, it is too late.
+ */
+#undef memcpy
+#undef memset
+#define memzero(s, n)	memset((s), 0, (n))
+#define memmove		memmove
+
+/* Functions used by the included decompressor code below. */
+void *memmove(void *dest, const void *src, size_t n);
+
+/*
+ * This is set up by the setup-routine at boot-time
+ */
+struct boot_params *boot_params;
+
+memptr free_mem_ptr;
+memptr free_mem_end_ptr;
+
+static char *vidmem;
+static int vidport;
+static int lines, cols;
+
+#ifdef CONFIG_KERNEL_GZIP
+#include "../../../../lib/decompress_inflate.c"
+#endif
+
+#ifdef CONFIG_KERNEL_BZIP2
+#include "../../../../lib/decompress_bunzip2.c"
+#endif
+
+#ifdef CONFIG_KERNEL_LZMA
+#include "../../../../lib/decompress_unlzma.c"
+#endif
+
+#ifdef CONFIG_KERNEL_XZ
+#include "../../../../lib/decompress_unxz.c"
+#endif
+
+#ifdef CONFIG_KERNEL_LZO
+#include "../../../../lib/decompress_unlzo.c"
+#endif
+
+#ifdef CONFIG_KERNEL_LZ4
+#include "../../../../lib/decompress_unlz4.c"
+#endif
+/*
+ * NOTE: When adding a new decompressor, please update the analysis in
+ * ../header.S.
+ */
+
+static void scroll(void)
+{
+	int i;
+
+	memmove(vidmem, vidmem + cols * 2, (lines - 1) * cols * 2);
+	for (i = (lines - 1) * cols * 2; i < lines * cols * 2; i += 2)
+		vidmem[i] = ' ';
+}
+
+#define XMTRDY          0x20
+
+#define TXR             0       /*  Transmit register (WRITE) */
+#define LSR             5       /*  Line Status               */
+static void serial_putchar(int ch)
+{
+	unsigned timeout = 0xffff;
+
+	while ((inb(early_serial_base + LSR) & XMTRDY) == 0 && --timeout)
+		cpu_relax();
+
+	outb(ch, early_serial_base + TXR);
+}
+
+void __putstr(const char *s)
+{
+	int x, y, pos;
+	char c;
+
+	if (early_serial_base) {
+		const char *str = s;
+		while (*str) {
+			if (*str == '\n')
+				serial_putchar('\r');
+			serial_putchar(*str++);
+		}
+	}
+
+	if (lines == 0 || cols == 0)
+		return;
+
+	x = boot_params->screen_info.orig_x;
+	y = boot_params->screen_info.orig_y;
+
+	while ((c = *s++) != '\0') {
+		if (c == '\n') {
+			x = 0;
+			if (++y >= lines) {
+				scroll();
+				y--;
+			}
+		} else {
+			vidmem[(x + cols * y) * 2] = c;
+			if (++x >= cols) {
+				x = 0;
+				if (++y >= lines) {
+					scroll();
+					y--;
+				}
+			}
+		}
+	}
+
+	boot_params->screen_info.orig_x = x;
+	boot_params->screen_info.orig_y = y;
+
+	pos = (x + cols * y) * 2;	/* Update cursor position */
+	outb(14, vidport);
+	outb(0xff & (pos >> 9), vidport+1);
+	outb(15, vidport);
+	outb(0xff & (pos >> 1), vidport+1);
+}
+
+void __puthex(unsigned long value)
+{
+	char alpha[2] = "0";
+	int bits;
+
+	for (bits = sizeof(value) * 8 - 4; bits >= 0; bits -= 4) {
+		unsigned long digit = (value >> bits) & 0xf;
+
+		if (digit < 0xA)
+			alpha[0] = '0' + digit;
+		else
+			alpha[0] = 'a' + (digit - 0xA);
+
+		__putstr(alpha);
+	}
+}
+
+#if CONFIG_X86_NEED_RELOCS
+static void handle_relocations(void *output, unsigned long output_len,
+			       unsigned long virt_addr)
+{
+	int *reloc;
+	unsigned long delta, map, ptr;
+	unsigned long min_addr = (unsigned long)output;
+	unsigned long max_addr = min_addr + (VO___bss_start - VO__text);
+
+	/*
+	 * Calculate the delta between where vmlinux was linked to load
+	 * and where it was actually loaded.
+	 */
+	delta = min_addr - LOAD_PHYSICAL_ADDR;
+
+	/*
+	 * The kernel contains a table of relocation addresses. Those
+	 * addresses have the final load address of the kernel in virtual
+	 * memory. We are currently working in the self map. So we need to
+	 * create an adjustment for kernel memory addresses to the self map.
+	 * This will involve subtracting out the base address of the kernel.
+	 */
+	map = delta - __START_KERNEL_map;
+
+	/*
+	 * 32-bit always performs relocations. 64-bit relocations are only
+	 * needed if KASLR has chosen a different starting address offset
+	 * from __START_KERNEL_map.
+	 */
+	if (IS_ENABLED(CONFIG_X86_64))
+		delta = virt_addr - LOAD_PHYSICAL_ADDR;
+
+	if (!delta) {
+		debug_putstr("No relocation needed... ");
+		return;
+	}
+	debug_putstr("Performing relocations... ");
+
+	/*
+	 * Process relocations: 32 bit relocations first then 64 bit after.
+	 * Three sets of binary relocations are added to the end of the kernel
+	 * before compression. Each relocation table entry is the kernel
+	 * address of the location which needs to be updated stored as a
+	 * 32-bit value which is sign extended to 64 bits.
+	 *
+	 * Format is:
+	 *
+	 * kernel bits...
+	 * 0 - zero terminator for 64 bit relocations
+	 * 64 bit relocation repeated
+	 * 0 - zero terminator for inverse 32 bit relocations
+	 * 32 bit inverse relocation repeated
+	 * 0 - zero terminator for 32 bit relocations
+	 * 32 bit relocation repeated
+	 *
+	 * So we work backwards from the end of the decompressed image.
+	 */
+	for (reloc = output + output_len - sizeof(*reloc); *reloc; reloc--) {
+		long extended = *reloc;
+		extended += map;
+
+		ptr = (unsigned long)extended;
+		if (ptr < min_addr || ptr > max_addr)
+			error("32-bit relocation outside of kernel!\n");
+
+		*(uint32_t *)ptr += delta;
+	}
+#ifdef CONFIG_X86_64
+	while (*--reloc) {
+		long extended = *reloc;
+		extended += map;
+
+		ptr = (unsigned long)extended;
+		if (ptr < min_addr || ptr > max_addr)
+			error("inverse 32-bit relocation outside of kernel!\n");
+
+		*(int32_t *)ptr -= delta;
+	}
+	for (reloc--; *reloc; reloc--) {
+		long extended = *reloc;
+		extended += map;
+
+		ptr = (unsigned long)extended;
+		if (ptr < min_addr || ptr > max_addr)
+			error("64-bit relocation outside of kernel!\n");
+
+		*(uint64_t *)ptr += delta;
+	}
+#endif
+}
+#else
+static inline void handle_relocations(void *output, unsigned long output_len,
+				      unsigned long virt_addr)
+{ }
+#endif
+
+static void parse_elf(void *output)
+{
+#ifdef CONFIG_X86_64
+	Elf64_Ehdr ehdr;
+	Elf64_Phdr *phdrs, *phdr;
+#else
+	Elf32_Ehdr ehdr;
+	Elf32_Phdr *phdrs, *phdr;
+#endif
+	void *dest;
+	int i;
+
+	memcpy(&ehdr, output, sizeof(ehdr));
+	if (ehdr.e_ident[EI_MAG0] != ELFMAG0 ||
+	   ehdr.e_ident[EI_MAG1] != ELFMAG1 ||
+	   ehdr.e_ident[EI_MAG2] != ELFMAG2 ||
+	   ehdr.e_ident[EI_MAG3] != ELFMAG3) {
+		error("Kernel is not a valid ELF file");
+		return;
+	}
+
+	debug_putstr("Parsing ELF... ");
+
+	phdrs = malloc(sizeof(*phdrs) * ehdr.e_phnum);
+	if (!phdrs)
+		error("Failed to allocate space for phdrs");
+
+	memcpy(phdrs, output + ehdr.e_phoff, sizeof(*phdrs) * ehdr.e_phnum);
+
+	for (i = 0; i < ehdr.e_phnum; i++) {
+		phdr = &phdrs[i];
+
+		switch (phdr->p_type) {
+		case PT_LOAD:
+#ifdef CONFIG_X86_64
+			if ((phdr->p_align % 0x200000) != 0)
+				error("Alignment of LOAD segment isn't multiple of 2MB");
+#endif
+#ifdef CONFIG_RELOCATABLE
+			dest = output;
+			dest += (phdr->p_paddr - LOAD_PHYSICAL_ADDR);
+#else
+			dest = (void *)(phdr->p_paddr);
+#endif
+			memmove(dest, output + phdr->p_offset, phdr->p_filesz);
+			break;
+		default: /* Ignore other PT_* */ break;
+		}
+	}
+
+	free(phdrs);
+}
+
+/*
+ * The compressed kernel image (ZO), has been moved so that its position
+ * is against the end of the buffer used to hold the uncompressed kernel
+ * image (VO) and the execution environment (.bss, .brk), which makes sure
+ * there is room to do the in-place decompression. (See header.S for the
+ * calculations.)
+ *
+ *                             |-----compressed kernel image------|
+ *                             V                                  V
+ * 0                       extract_offset                      +INIT_SIZE
+ * |-----------|---------------|-------------------------|--------|
+ *             |               |                         |        |
+ *           VO__text      startup_32 of ZO          VO__end    ZO__end
+ *             ^                                         ^
+ *             |-------uncompressed kernel image---------|
+ *
+ */
+asmlinkage __visible void *extract_kernel(void *rmode, memptr heap,
+				  unsigned char *input_data,
+				  unsigned long input_len,
+				  unsigned char *output,
+				  unsigned long output_len)
+{
+	const unsigned long kernel_total_size = VO__end - VO__text;
+	unsigned long virt_addr = LOAD_PHYSICAL_ADDR;
+
+	/* Retain x86 boot parameters pointer passed from startup_32/64. */
+	boot_params = rmode;
+
+	/* Clear flags intended for solely in-kernel use. */
+	boot_params->hdr.loadflags &= ~KASLR_FLAG;
+
+	sanitize_boot_params(boot_params);
+
+	if (boot_params->screen_info.orig_video_mode == 7) {
+		vidmem = (char *) 0xb0000;
+		vidport = 0x3b4;
+	} else {
+		vidmem = (char *) 0xb8000;
+		vidport = 0x3d4;
+	}
+
+	lines = boot_params->screen_info.orig_video_lines;
+	cols = boot_params->screen_info.orig_video_cols;
+
+	console_init();
+	debug_putstr("early console in extract_kernel\n");
+
+	free_mem_ptr     = heap;	/* Heap */
+	free_mem_end_ptr = heap + BOOT_HEAP_SIZE;
+
+	/* Report initial kernel position details. */
+	debug_putaddr(input_data);
+	debug_putaddr(input_len);
+	debug_putaddr(output);
+	debug_putaddr(output_len);
+	debug_putaddr(kernel_total_size);
+
+#ifdef CONFIG_X86_64
+	/* Report address of 32-bit trampoline */
+	debug_putaddr(trampoline_32bit);
+#endif
+
+	/*
+	 * The memory hole needed for the kernel is the larger of either
+	 * the entire decompressed kernel plus relocation table, or the
+	 * entire decompressed kernel plus .bss and .brk sections.
+	 */
+	choose_random_location((unsigned long)input_data, input_len,
+				(unsigned long *)&output,
+				max(output_len, kernel_total_size),
+				&virt_addr);
+
+	/* Validate memory location choices. */
+	if ((unsigned long)output & (MIN_KERNEL_ALIGN - 1))
+		error("Destination physical address inappropriately aligned");
+	if (virt_addr & (MIN_KERNEL_ALIGN - 1))
+		error("Destination virtual address inappropriately aligned");
+#ifdef CONFIG_X86_64
+	if (heap > 0x3fffffffffffUL)
+		error("Destination address too large");
+	if (virt_addr + max(output_len, kernel_total_size) > KERNEL_IMAGE_SIZE)
+		error("Destination virtual address is beyond the kernel mapping area");
+#else
+	if (heap > ((-__PAGE_OFFSET-(128<<20)-1) & 0x7fffffff))
+		error("Destination address too large");
+#endif
+#ifndef CONFIG_RELOCATABLE
+	if ((unsigned long)output != LOAD_PHYSICAL_ADDR)
+		error("Destination address does not match LOAD_PHYSICAL_ADDR");
+	if (virt_addr != LOAD_PHYSICAL_ADDR)
+		error("Destination virtual address changed when not relocatable");
+#endif
+
+	debug_putstr("\nDecompressing Linux... ");
+	__decompress(input_data, input_len, NULL, NULL, output, output_len,
+			NULL, error);
+	parse_elf(output);
+	handle_relocations(output, output_len, virt_addr);
+	debug_putstr("done.\nBooting the kernel.\n");
+	return output;
+}
+
+void fortify_panic(const char *name)
+{
+	error("detected buffer overflow");
+}