linux/arch/arm/boot/compressed/misc.c
Kees Cook 475ddf1fce fortify: Split reporting and avoid passing string pointer
In preparation for KUnit testing and further improvements in fortify
failure reporting, split out the report and encode the function and access
failure (read or write overflow) into a single u8 argument. This mainly
ends up saving a tiny bit of space in the data segment. For a defconfig
with FORTIFY_SOURCE enabled:

$ size gcc/vmlinux.before gcc/vmlinux.after
   text  	  data     bss     dec    	    hex filename
26132309        9760658 2195460 38088427        2452eeb gcc/vmlinux.before
26132386        9748382 2195460 38076228        244ff44 gcc/vmlinux.after

Reviewed-by: Alexander Lobakin <aleksander.lobakin@intel.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
2024-02-29 13:38:02 -08:00

160 lines
3 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* misc.c
*
* This is a collection of several routines from gzip-1.0.3
* adapted for Linux.
*
* malloc by Hannu Savolainen 1993 and Matthias Urlichs 1994
*
* Modified for ARM Linux by Russell King
*
* Nicolas Pitre <nico@visuaide.com> 1999/04/14 :
* For this code to run directly from Flash, all constant variables must
* be marked with 'const' and all other variables initialized at run-time
* only. This way all non constant variables will end up in the bss segment,
* which should point to addresses in RAM and cleared to 0 on start.
* This allows for a much quicker boot time.
*/
unsigned int __machine_arch_type;
#include <linux/compiler.h> /* for inline */
#include <linux/types.h>
#include <linux/linkage.h>
#include "misc.h"
#ifdef CONFIG_ARCH_EP93XX
#include "misc-ep93xx.h"
#endif
static void putstr(const char *ptr);
#include CONFIG_UNCOMPRESS_INCLUDE
#ifdef CONFIG_DEBUG_ICEDCC
#if defined(CONFIG_CPU_V6) || defined(CONFIG_CPU_V6K) || defined(CONFIG_CPU_V7)
static void icedcc_putc(int ch)
{
int status, i = 0x4000000;
do {
if (--i < 0)
return;
asm volatile ("mrc p14, 0, %0, c0, c1, 0" : "=r" (status));
} while (status & (1 << 29));
asm("mcr p14, 0, %0, c0, c5, 0" : : "r" (ch));
}
#elif defined(CONFIG_CPU_XSCALE)
static void icedcc_putc(int ch)
{
int status, i = 0x4000000;
do {
if (--i < 0)
return;
asm volatile ("mrc p14, 0, %0, c14, c0, 0" : "=r" (status));
} while (status & (1 << 28));
asm("mcr p14, 0, %0, c8, c0, 0" : : "r" (ch));
}
#else
static void icedcc_putc(int ch)
{
int status, i = 0x4000000;
do {
if (--i < 0)
return;
asm volatile ("mrc p14, 0, %0, c0, c0, 0" : "=r" (status));
} while (status & 2);
asm("mcr p14, 0, %0, c1, c0, 0" : : "r" (ch));
}
#endif
#define putc(ch) icedcc_putc(ch)
#endif
static void putstr(const char *ptr)
{
char c;
while ((c = *ptr++) != '\0') {
if (c == '\n')
putc('\r');
putc(c);
}
flush();
}
/*
* gzip declarations
*/
unsigned char *output_data;
unsigned long free_mem_ptr;
unsigned long free_mem_end_ptr;
#ifndef arch_error
#define arch_error(x)
#endif
void error(char *x)
{
arch_error(x);
putstr("\n\n");
putstr(x);
putstr("\n\n -- System halted");
while(1); /* Halt */
}
asmlinkage void __div0(void)
{
error("Attempting division by 0!");
}
void
decompress_kernel(unsigned long output_start, unsigned long free_mem_ptr_p,
unsigned long free_mem_ptr_end_p,
int arch_id)
{
int ret;
output_data = (unsigned char *)output_start;
free_mem_ptr = free_mem_ptr_p;
free_mem_end_ptr = free_mem_ptr_end_p;
__machine_arch_type = arch_id;
#ifdef CONFIG_ARCH_EP93XX
ep93xx_decomp_setup();
#endif
arch_decomp_setup();
putstr("Uncompressing Linux...");
ret = do_decompress(input_data, input_data_end - input_data,
output_data, error);
if (ret)
error("decompressor returned an error");
else
putstr(" done, booting the kernel.\n");
}
void __fortify_panic(const u8 reason)
{
error("detected buffer overflow");
}