linux/arch/s390/kernel/kexec_elf.c
Baoquan He 865e2acd3e s390, crash: wrap crash dumping code into crash related ifdefs
Now crash codes under kernel/ folder has been split out from kexec
code, crash dumping can be separated from kexec reboot in config
items on s390 with some adjustments.

Here wrap up crash dumping codes with CONFIG_CRASH_DUMP ifdeffery.

Link: https://lkml.kernel.org/r/20240124051254.67105-10-bhe@redhat.com
Signed-off-by: Baoquan He <bhe@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Cc: Hari Bathini <hbathini@linux.ibm.com>
Cc: Pingfan Liu <piliu@redhat.com>
Cc: Klara Modin <klarasmodin@gmail.com>
Cc: Michael Kelley <mhklinux@outlook.com>
Cc: Nathan Chancellor <nathan@kernel.org>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Yang Li <yang.lee@linux.alibaba.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-02-23 17:48:23 -08:00

139 lines
3.3 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* ELF loader for kexec_file_load system call.
*
* Copyright IBM Corp. 2018
*
* Author(s): Philipp Rudo <prudo@linux.vnet.ibm.com>
*/
#include <linux/errno.h>
#include <linux/kernel.h>
#include <linux/kexec.h>
#include <asm/ipl.h>
#include <asm/setup.h>
static int kexec_file_add_kernel_elf(struct kimage *image,
struct s390_load_data *data)
{
struct kexec_buf buf;
const Elf_Ehdr *ehdr;
const Elf_Phdr *phdr;
Elf_Addr entry;
void *kernel;
int i, ret;
kernel = image->kernel_buf;
ehdr = (Elf_Ehdr *)kernel;
buf.image = image;
if (image->type == KEXEC_TYPE_CRASH)
entry = STARTUP_KDUMP_OFFSET;
else
entry = ehdr->e_entry;
phdr = (void *)ehdr + ehdr->e_phoff;
for (i = 0; i < ehdr->e_phnum; i++, phdr++) {
if (phdr->p_type != PT_LOAD)
continue;
buf.buffer = kernel + phdr->p_offset;
buf.bufsz = phdr->p_filesz;
buf.mem = ALIGN(phdr->p_paddr, phdr->p_align);
#ifdef CONFIG_CRASH_DUMP
if (image->type == KEXEC_TYPE_CRASH)
buf.mem += crashk_res.start;
#endif
buf.memsz = phdr->p_memsz;
data->memsz = ALIGN(data->memsz, phdr->p_align) + buf.memsz;
if (entry - phdr->p_paddr < phdr->p_memsz) {
data->kernel_buf = buf.buffer;
data->kernel_mem = buf.mem;
data->parm = buf.buffer + PARMAREA;
}
ipl_report_add_component(data->report, &buf,
IPL_RB_COMPONENT_FLAG_SIGNED |
IPL_RB_COMPONENT_FLAG_VERIFIED,
IPL_RB_CERT_UNKNOWN);
ret = kexec_add_buffer(&buf);
if (ret)
return ret;
}
return data->memsz ? 0 : -EINVAL;
}
static void *s390_elf_load(struct kimage *image,
char *kernel, unsigned long kernel_len,
char *initrd, unsigned long initrd_len,
char *cmdline, unsigned long cmdline_len)
{
const Elf_Ehdr *ehdr;
const Elf_Phdr *phdr;
size_t size;
int i;
/* image->fobs->probe already checked for valid ELF magic number. */
ehdr = (Elf_Ehdr *)kernel;
if (ehdr->e_type != ET_EXEC ||
ehdr->e_ident[EI_CLASS] != ELFCLASS64 ||
!elf_check_arch(ehdr))
return ERR_PTR(-EINVAL);
if (!ehdr->e_phnum || ehdr->e_phentsize != sizeof(Elf_Phdr))
return ERR_PTR(-EINVAL);
size = ehdr->e_ehsize + ehdr->e_phoff;
size += ehdr->e_phentsize * ehdr->e_phnum;
if (size > kernel_len)
return ERR_PTR(-EINVAL);
phdr = (void *)ehdr + ehdr->e_phoff;
size = ALIGN(size, phdr->p_align);
for (i = 0; i < ehdr->e_phnum; i++, phdr++) {
if (phdr->p_type == PT_INTERP)
return ERR_PTR(-EINVAL);
if (phdr->p_offset > kernel_len)
return ERR_PTR(-EINVAL);
size += ALIGN(phdr->p_filesz, phdr->p_align);
}
if (size > kernel_len)
return ERR_PTR(-EINVAL);
return kexec_file_add_components(image, kexec_file_add_kernel_elf);
}
static int s390_elf_probe(const char *buf, unsigned long len)
{
const Elf_Ehdr *ehdr;
if (len < sizeof(Elf_Ehdr))
return -ENOEXEC;
ehdr = (Elf_Ehdr *)buf;
/* Only check the ELF magic number here and do proper validity check
* in the loader. Any check here that fails would send the erroneous
* ELF file to the image loader that does not care what it gets.
* (Most likely) causing behavior not intended by the user.
*/
if (memcmp(ehdr->e_ident, ELFMAG, SELFMAG) != 0)
return -ENOEXEC;
return 0;
}
const struct kexec_file_ops s390_kexec_elf_ops = {
.probe = s390_elf_probe,
.load = s390_elf_load,
#ifdef CONFIG_KEXEC_SIG
.verify_sig = s390_verify_sig,
#endif /* CONFIG_KEXEC_SIG */
};