linux-stable/kernel/kexec_file.c

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// SPDX-License-Identifier: GPL-2.0-only
/*
* kexec: kexec_file_load system call
*
* Copyright (C) 2014 Red Hat Inc.
* Authors:
* Vivek Goyal <vgoyal@redhat.com>
*/
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#include <linux/capability.h>
#include <linux/mm.h>
#include <linux/file.h>
#include <linux/slab.h>
#include <linux/kexec.h>
#include <linux/memblock.h>
#include <linux/mutex.h>
#include <linux/list.h>
#include <linux/fs.h>
#include <linux/ima.h>
#include <crypto/hash.h>
#include <crypto/sha2.h>
#include <linux/elf.h>
#include <linux/elfcore.h>
#include <linux/kernel.h>
#include <linux/kernel_read_file.h>
#include <linux/syscalls.h>
#include <linux/vmalloc.h>
#include "kexec_internal.h"
static int kexec_calculate_store_digests(struct kimage *image);
/*
* Currently this is the only default function that is exported as some
* architectures need it to do additional handlings.
* In the future, other default functions may be exported too if required.
*/
int kexec_image_probe_default(struct kimage *image, void *buf,
unsigned long buf_len)
{
const struct kexec_file_ops * const *fops;
int ret = -ENOEXEC;
for (fops = &kexec_file_loaders[0]; *fops && (*fops)->probe; ++fops) {
ret = (*fops)->probe(buf, buf_len);
if (!ret) {
image->fops = *fops;
return ret;
}
}
return ret;
}
/* Architectures can provide this probe function */
int __weak arch_kexec_kernel_image_probe(struct kimage *image, void *buf,
unsigned long buf_len)
{
return kexec_image_probe_default(image, buf, buf_len);
}
static void *kexec_image_load_default(struct kimage *image)
{
if (!image->fops || !image->fops->load)
return ERR_PTR(-ENOEXEC);
return image->fops->load(image, image->kernel_buf,
image->kernel_buf_len, image->initrd_buf,
image->initrd_buf_len, image->cmdline_buf,
image->cmdline_buf_len);
}
void * __weak arch_kexec_kernel_image_load(struct kimage *image)
{
return kexec_image_load_default(image);
}
int kexec_image_post_load_cleanup_default(struct kimage *image)
{
if (!image->fops || !image->fops->cleanup)
return 0;
return image->fops->cleanup(image->image_loader_data);
}
int __weak arch_kimage_file_post_load_cleanup(struct kimage *image)
{
return kexec_image_post_load_cleanup_default(image);
}
#ifdef CONFIG_KEXEC_SIG
static int kexec_image_verify_sig_default(struct kimage *image, void *buf,
unsigned long buf_len)
{
if (!image->fops || !image->fops->verify_sig) {
pr_debug("kernel loader does not support signature verification.\n");
return -EKEYREJECTED;
}
return image->fops->verify_sig(buf, buf_len);
}
int __weak arch_kexec_kernel_verify_sig(struct kimage *image, void *buf,
unsigned long buf_len)
{
return kexec_image_verify_sig_default(image, buf, buf_len);
}
#endif
/*
* Free up memory used by kernel, initrd, and command line. This is temporary
* memory allocation which is not needed any more after these buffers have
* been loaded into separate segments and have been copied elsewhere.
*/
void kimage_file_post_load_cleanup(struct kimage *image)
{
struct purgatory_info *pi = &image->purgatory_info;
vfree(image->kernel_buf);
image->kernel_buf = NULL;
vfree(image->initrd_buf);
image->initrd_buf = NULL;
kfree(image->cmdline_buf);
image->cmdline_buf = NULL;
vfree(pi->purgatory_buf);
pi->purgatory_buf = NULL;
vfree(pi->sechdrs);
pi->sechdrs = NULL;
#ifdef CONFIG_IMA_KEXEC
vfree(image->ima_buffer);
image->ima_buffer = NULL;
#endif /* CONFIG_IMA_KEXEC */
/* See if architecture has anything to cleanup post load */
arch_kimage_file_post_load_cleanup(image);
/*
* Above call should have called into bootloader to free up
* any data stored in kimage->image_loader_data. It should
* be ok now to free it up.
*/
kfree(image->image_loader_data);
image->image_loader_data = NULL;
}
#ifdef CONFIG_KEXEC_SIG
static int
kimage_validate_signature(struct kimage *image)
{
int ret;
ret = arch_kexec_kernel_verify_sig(image, image->kernel_buf,
image->kernel_buf_len);
kexec: do not verify the signature without the lockdown or mandatory signature Signature verification is an important security feature, to protect system from being attacked with a kernel of unknown origin. Kexec rebooting is a way to replace the running kernel, hence need be secured carefully. In the current code of handling signature verification of kexec kernel, the logic is very twisted. It mixes signature verification, IMA signature appraising and kexec lockdown. If there is no KEXEC_SIG_FORCE, kexec kernel image doesn't have one of signature, the supported crypto, and key, we don't think this is wrong, Unless kexec lockdown is executed. IMA is considered as another kind of signature appraising method. If kexec kernel image has signature/crypto/key, it has to go through the signature verification and pass. Otherwise it's seen as verification failure, and won't be loaded. Seems kexec kernel image with an unqualified signature is even worse than those w/o signature at all, this sounds very unreasonable. E.g. If people get a unsigned kernel to load, or a kernel signed with expired key, which one is more dangerous? So, here, let's simplify the logic to improve code readability. If the KEXEC_SIG_FORCE enabled or kexec lockdown enabled, signature verification is mandated. Otherwise, we lift the bar for any kernel image. Link: http://lkml.kernel.org/r/20200602045952.27487-1-lijiang@redhat.com Signed-off-by: Lianbo Jiang <lijiang@redhat.com> Reviewed-by: Jiri Bohac <jbohac@suse.cz> Acked-by: Dave Young <dyoung@redhat.com> Acked-by: Baoquan He <bhe@redhat.com> Cc: James Morris <jmorris@namei.org> Cc: Matthew Garrett <mjg59@google.com> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-26 03:29:27 +00:00
if (ret) {
if (IS_ENABLED(CONFIG_KEXEC_SIG_FORCE)) {
kexec: do not verify the signature without the lockdown or mandatory signature Signature verification is an important security feature, to protect system from being attacked with a kernel of unknown origin. Kexec rebooting is a way to replace the running kernel, hence need be secured carefully. In the current code of handling signature verification of kexec kernel, the logic is very twisted. It mixes signature verification, IMA signature appraising and kexec lockdown. If there is no KEXEC_SIG_FORCE, kexec kernel image doesn't have one of signature, the supported crypto, and key, we don't think this is wrong, Unless kexec lockdown is executed. IMA is considered as another kind of signature appraising method. If kexec kernel image has signature/crypto/key, it has to go through the signature verification and pass. Otherwise it's seen as verification failure, and won't be loaded. Seems kexec kernel image with an unqualified signature is even worse than those w/o signature at all, this sounds very unreasonable. E.g. If people get a unsigned kernel to load, or a kernel signed with expired key, which one is more dangerous? So, here, let's simplify the logic to improve code readability. If the KEXEC_SIG_FORCE enabled or kexec lockdown enabled, signature verification is mandated. Otherwise, we lift the bar for any kernel image. Link: http://lkml.kernel.org/r/20200602045952.27487-1-lijiang@redhat.com Signed-off-by: Lianbo Jiang <lijiang@redhat.com> Reviewed-by: Jiri Bohac <jbohac@suse.cz> Acked-by: Dave Young <dyoung@redhat.com> Acked-by: Baoquan He <bhe@redhat.com> Cc: James Morris <jmorris@namei.org> Cc: Matthew Garrett <mjg59@google.com> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-26 03:29:27 +00:00
pr_notice("Enforced kernel signature verification failed (%d).\n", ret);
return ret;
}
kexec: do not verify the signature without the lockdown or mandatory signature Signature verification is an important security feature, to protect system from being attacked with a kernel of unknown origin. Kexec rebooting is a way to replace the running kernel, hence need be secured carefully. In the current code of handling signature verification of kexec kernel, the logic is very twisted. It mixes signature verification, IMA signature appraising and kexec lockdown. If there is no KEXEC_SIG_FORCE, kexec kernel image doesn't have one of signature, the supported crypto, and key, we don't think this is wrong, Unless kexec lockdown is executed. IMA is considered as another kind of signature appraising method. If kexec kernel image has signature/crypto/key, it has to go through the signature verification and pass. Otherwise it's seen as verification failure, and won't be loaded. Seems kexec kernel image with an unqualified signature is even worse than those w/o signature at all, this sounds very unreasonable. E.g. If people get a unsigned kernel to load, or a kernel signed with expired key, which one is more dangerous? So, here, let's simplify the logic to improve code readability. If the KEXEC_SIG_FORCE enabled or kexec lockdown enabled, signature verification is mandated. Otherwise, we lift the bar for any kernel image. Link: http://lkml.kernel.org/r/20200602045952.27487-1-lijiang@redhat.com Signed-off-by: Lianbo Jiang <lijiang@redhat.com> Reviewed-by: Jiri Bohac <jbohac@suse.cz> Acked-by: Dave Young <dyoung@redhat.com> Acked-by: Baoquan He <bhe@redhat.com> Cc: James Morris <jmorris@namei.org> Cc: Matthew Garrett <mjg59@google.com> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-26 03:29:27 +00:00
/*
* If IMA is guaranteed to appraise a signature on the kexec
* image, permit it even if the kernel is otherwise locked
* down.
*/
if (!ima_appraise_signature(READING_KEXEC_IMAGE) &&
security_locked_down(LOCKDOWN_KEXEC))
return -EPERM;
kexec: do not verify the signature without the lockdown or mandatory signature Signature verification is an important security feature, to protect system from being attacked with a kernel of unknown origin. Kexec rebooting is a way to replace the running kernel, hence need be secured carefully. In the current code of handling signature verification of kexec kernel, the logic is very twisted. It mixes signature verification, IMA signature appraising and kexec lockdown. If there is no KEXEC_SIG_FORCE, kexec kernel image doesn't have one of signature, the supported crypto, and key, we don't think this is wrong, Unless kexec lockdown is executed. IMA is considered as another kind of signature appraising method. If kexec kernel image has signature/crypto/key, it has to go through the signature verification and pass. Otherwise it's seen as verification failure, and won't be loaded. Seems kexec kernel image with an unqualified signature is even worse than those w/o signature at all, this sounds very unreasonable. E.g. If people get a unsigned kernel to load, or a kernel signed with expired key, which one is more dangerous? So, here, let's simplify the logic to improve code readability. If the KEXEC_SIG_FORCE enabled or kexec lockdown enabled, signature verification is mandated. Otherwise, we lift the bar for any kernel image. Link: http://lkml.kernel.org/r/20200602045952.27487-1-lijiang@redhat.com Signed-off-by: Lianbo Jiang <lijiang@redhat.com> Reviewed-by: Jiri Bohac <jbohac@suse.cz> Acked-by: Dave Young <dyoung@redhat.com> Acked-by: Baoquan He <bhe@redhat.com> Cc: James Morris <jmorris@namei.org> Cc: Matthew Garrett <mjg59@google.com> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-26 03:29:27 +00:00
pr_debug("kernel signature verification failed (%d).\n", ret);
}
kexec: do not verify the signature without the lockdown or mandatory signature Signature verification is an important security feature, to protect system from being attacked with a kernel of unknown origin. Kexec rebooting is a way to replace the running kernel, hence need be secured carefully. In the current code of handling signature verification of kexec kernel, the logic is very twisted. It mixes signature verification, IMA signature appraising and kexec lockdown. If there is no KEXEC_SIG_FORCE, kexec kernel image doesn't have one of signature, the supported crypto, and key, we don't think this is wrong, Unless kexec lockdown is executed. IMA is considered as another kind of signature appraising method. If kexec kernel image has signature/crypto/key, it has to go through the signature verification and pass. Otherwise it's seen as verification failure, and won't be loaded. Seems kexec kernel image with an unqualified signature is even worse than those w/o signature at all, this sounds very unreasonable. E.g. If people get a unsigned kernel to load, or a kernel signed with expired key, which one is more dangerous? So, here, let's simplify the logic to improve code readability. If the KEXEC_SIG_FORCE enabled or kexec lockdown enabled, signature verification is mandated. Otherwise, we lift the bar for any kernel image. Link: http://lkml.kernel.org/r/20200602045952.27487-1-lijiang@redhat.com Signed-off-by: Lianbo Jiang <lijiang@redhat.com> Reviewed-by: Jiri Bohac <jbohac@suse.cz> Acked-by: Dave Young <dyoung@redhat.com> Acked-by: Baoquan He <bhe@redhat.com> Cc: James Morris <jmorris@namei.org> Cc: Matthew Garrett <mjg59@google.com> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-26 03:29:27 +00:00
return 0;
}
#endif
/*
* In file mode list of segments is prepared by kernel. Copy relevant
* data from user space, do error checking, prepare segment list
*/
static int
kimage_file_prepare_segments(struct kimage *image, int kernel_fd, int initrd_fd,
const char __user *cmdline_ptr,
unsigned long cmdline_len, unsigned flags)
{
int ret;
void *ldata;
ret = kernel_read_file_from_fd(kernel_fd, 0, &image->kernel_buf,
INT_MAX, NULL, READING_KEXEC_IMAGE);
if (ret < 0)
return ret;
image->kernel_buf_len = ret;
/* Call arch image probe handlers */
ret = arch_kexec_kernel_image_probe(image, image->kernel_buf,
image->kernel_buf_len);
if (ret)
goto out;
#ifdef CONFIG_KEXEC_SIG
ret = kimage_validate_signature(image);
if (ret)
goto out;
#endif
/* It is possible that there no initramfs is being loaded */
if (!(flags & KEXEC_FILE_NO_INITRAMFS)) {
ret = kernel_read_file_from_fd(initrd_fd, 0, &image->initrd_buf,
INT_MAX, NULL,
READING_KEXEC_INITRAMFS);
if (ret < 0)
goto out;
image->initrd_buf_len = ret;
ret = 0;
}
if (cmdline_len) {
image->cmdline_buf = memdup_user(cmdline_ptr, cmdline_len);
if (IS_ERR(image->cmdline_buf)) {
ret = PTR_ERR(image->cmdline_buf);
image->cmdline_buf = NULL;
goto out;
}
image->cmdline_buf_len = cmdline_len;
/* command line should be a string with last byte null */
if (image->cmdline_buf[cmdline_len - 1] != '\0') {
ret = -EINVAL;
goto out;
}
2020-07-09 06:19:11 +00:00
ima_kexec_cmdline(kernel_fd, image->cmdline_buf,
image->cmdline_buf_len - 1);
}
/* IMA needs to pass the measurement list to the next kernel. */
ima_add_kexec_buffer(image);
/* Call arch image load handlers */
ldata = arch_kexec_kernel_image_load(image);
if (IS_ERR(ldata)) {
ret = PTR_ERR(ldata);
goto out;
}
image->image_loader_data = ldata;
out:
/* In case of error, free up all allocated memory in this function */
if (ret)
kimage_file_post_load_cleanup(image);
return ret;
}
static int
kimage_file_alloc_init(struct kimage **rimage, int kernel_fd,
int initrd_fd, const char __user *cmdline_ptr,
unsigned long cmdline_len, unsigned long flags)
{
int ret;
struct kimage *image;
bool kexec_on_panic = flags & KEXEC_FILE_ON_CRASH;
image = do_kimage_alloc_init();
if (!image)
return -ENOMEM;
image->file_mode = 1;
if (kexec_on_panic) {
/* Enable special crash kernel control page alloc policy. */
image->control_page = crashk_res.start;
image->type = KEXEC_TYPE_CRASH;
}
ret = kimage_file_prepare_segments(image, kernel_fd, initrd_fd,
cmdline_ptr, cmdline_len, flags);
if (ret)
goto out_free_image;
ret = sanity_check_segment_list(image);
if (ret)
goto out_free_post_load_bufs;
ret = -ENOMEM;
image->control_code_page = kimage_alloc_control_pages(image,
get_order(KEXEC_CONTROL_PAGE_SIZE));
if (!image->control_code_page) {
pr_err("Could not allocate control_code_buffer\n");
goto out_free_post_load_bufs;
}
if (!kexec_on_panic) {
image->swap_page = kimage_alloc_control_pages(image, 0);
if (!image->swap_page) {
pr_err("Could not allocate swap buffer\n");
goto out_free_control_pages;
}
}
*rimage = image;
return 0;
out_free_control_pages:
kimage_free_page_list(&image->control_pages);
out_free_post_load_bufs:
kimage_file_post_load_cleanup(image);
out_free_image:
kfree(image);
return ret;
}
SYSCALL_DEFINE5(kexec_file_load, int, kernel_fd, int, initrd_fd,
unsigned long, cmdline_len, const char __user *, cmdline_ptr,
unsigned long, flags)
{
int ret = 0, i;
struct kimage **dest_image, *image;
/* We only trust the superuser with rebooting the system. */
if (!capable(CAP_SYS_BOOT) || kexec_load_disabled)
return -EPERM;
/* Make sure we have a legal set of flags */
if (flags != (flags & KEXEC_FILE_FLAGS))
return -EINVAL;
image = NULL;
if (!mutex_trylock(&kexec_mutex))
return -EBUSY;
dest_image = &kexec_image;
if (flags & KEXEC_FILE_ON_CRASH) {
dest_image = &kexec_crash_image;
if (kexec_crash_image)
arch_kexec_unprotect_crashkres();
}
if (flags & KEXEC_FILE_UNLOAD)
goto exchange;
/*
* In case of crash, new kernel gets loaded in reserved region. It is
* same memory where old crash kernel might be loaded. Free any
* current crash dump kernel before we corrupt it.
*/
if (flags & KEXEC_FILE_ON_CRASH)
kimage_free(xchg(&kexec_crash_image, NULL));
ret = kimage_file_alloc_init(&image, kernel_fd, initrd_fd, cmdline_ptr,
cmdline_len, flags);
if (ret)
goto out;
ret = machine_kexec_prepare(image);
if (ret)
goto out;
kdump: protect vmcoreinfo data under the crash memory Currently vmcoreinfo data is updated at boot time subsys_initcall(), it has the risk of being modified by some wrong code during system is running. As a result, vmcore dumped may contain the wrong vmcoreinfo. Later on, when using "crash", "makedumpfile", etc utility to parse this vmcore, we probably will get "Segmentation fault" or other unexpected errors. E.g. 1) wrong code overwrites vmcoreinfo_data; 2) further crashes the system; 3) trigger kdump, then we obviously will fail to recognize the crash context correctly due to the corrupted vmcoreinfo. Now except for vmcoreinfo, all the crash data is well protected(including the cpu note which is fully updated in the crash path, thus its correctness is guaranteed). Given that vmcoreinfo data is a large chunk prepared for kdump, we better protect it as well. To solve this, we relocate and copy vmcoreinfo_data to the crash memory when kdump is loading via kexec syscalls. Because the whole crash memory will be protected by existing arch_kexec_protect_crashkres() mechanism, we naturally protect vmcoreinfo_data from write(even read) access under kernel direct mapping after kdump is loaded. Since kdump is usually loaded at the very early stage after boot, we can trust the correctness of the vmcoreinfo data copied. On the other hand, we still need to operate the vmcoreinfo safe copy when crash happens to generate vmcoreinfo_note again, we rely on vmap() to map out a new kernel virtual address and update to use this new one instead in the following crash_save_vmcoreinfo(). BTW, we do not touch vmcoreinfo_note, because it will be fully updated using the protected vmcoreinfo_data after crash which is surely correct just like the cpu crash note. Link: http://lkml.kernel.org/r/1493281021-20737-3-git-send-email-xlpang@redhat.com Signed-off-by: Xunlei Pang <xlpang@redhat.com> Tested-by: Michael Holzheu <holzheu@linux.vnet.ibm.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Dave Young <dyoung@redhat.com> Cc: Eric Biederman <ebiederm@xmission.com> Cc: Hari Bathini <hbathini@linux.vnet.ibm.com> Cc: Juergen Gross <jgross@suse.com> Cc: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-07-12 21:33:21 +00:00
/*
* Some architecture(like S390) may touch the crash memory before
* machine_kexec_prepare(), we must copy vmcoreinfo data after it.
*/
ret = kimage_crash_copy_vmcoreinfo(image);
if (ret)
goto out;
ret = kexec_calculate_store_digests(image);
if (ret)
goto out;
for (i = 0; i < image->nr_segments; i++) {
struct kexec_segment *ksegment;
ksegment = &image->segment[i];
pr_debug("Loading segment %d: buf=0x%p bufsz=0x%zx mem=0x%lx memsz=0x%zx\n",
i, ksegment->buf, ksegment->bufsz, ksegment->mem,
ksegment->memsz);
ret = kimage_load_segment(image, &image->segment[i]);
if (ret)
goto out;
}
kimage_terminate(image);
ret = machine_kexec_post_load(image);
if (ret)
goto out;
/*
* Free up any temporary buffers allocated which are not needed
* after image has been loaded
*/
kimage_file_post_load_cleanup(image);
exchange:
image = xchg(dest_image, image);
out:
if ((flags & KEXEC_FILE_ON_CRASH) && kexec_crash_image)
arch_kexec_protect_crashkres();
mutex_unlock(&kexec_mutex);
kimage_free(image);
return ret;
}
static int locate_mem_hole_top_down(unsigned long start, unsigned long end,
struct kexec_buf *kbuf)
{
struct kimage *image = kbuf->image;
unsigned long temp_start, temp_end;
temp_end = min(end, kbuf->buf_max);
temp_start = temp_end - kbuf->memsz;
do {
/* align down start */
temp_start = temp_start & (~(kbuf->buf_align - 1));
if (temp_start < start || temp_start < kbuf->buf_min)
return 0;
temp_end = temp_start + kbuf->memsz - 1;
/*
* Make sure this does not conflict with any of existing
* segments
*/
if (kimage_is_destination_range(image, temp_start, temp_end)) {
temp_start = temp_start - PAGE_SIZE;
continue;
}
/* We found a suitable memory range */
break;
} while (1);
/* If we are here, we found a suitable memory range */
kbuf->mem = temp_start;
/* Success, stop navigating through remaining System RAM ranges */
return 1;
}
static int locate_mem_hole_bottom_up(unsigned long start, unsigned long end,
struct kexec_buf *kbuf)
{
struct kimage *image = kbuf->image;
unsigned long temp_start, temp_end;
temp_start = max(start, kbuf->buf_min);
do {
temp_start = ALIGN(temp_start, kbuf->buf_align);
temp_end = temp_start + kbuf->memsz - 1;
if (temp_end > end || temp_end > kbuf->buf_max)
return 0;
/*
* Make sure this does not conflict with any of existing
* segments
*/
if (kimage_is_destination_range(image, temp_start, temp_end)) {
temp_start = temp_start + PAGE_SIZE;
continue;
}
/* We found a suitable memory range */
break;
} while (1);
/* If we are here, we found a suitable memory range */
kbuf->mem = temp_start;
/* Success, stop navigating through remaining System RAM ranges */
return 1;
}
static int locate_mem_hole_callback(struct resource *res, void *arg)
{
struct kexec_buf *kbuf = (struct kexec_buf *)arg;
u64 start = res->start, end = res->end;
unsigned long sz = end - start + 1;
/* Returning 0 will take to next memory range */
/* Don't use memory that will be detected and handled by a driver. */
kernel/resource: move and rename IORESOURCE_MEM_DRIVER_MANAGED IORESOURCE_MEM_DRIVER_MANAGED currently uses an unused PnP bit, which is always set to 0 by hardware. This is far from beautiful (and confusing), and the bit only applies to SYSRAM. So let's move it out of the bus-specific (PnP) defined bits. We'll add another SYSRAM specific bit soon. If we ever need more bits for other purposes, we can steal some from "desc", or reshuffle/regroup what we have. Signed-off-by: David Hildenbrand <david@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Cc: Michal Hocko <mhocko@suse.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Jason Gunthorpe <jgg@ziepe.ca> Cc: Kees Cook <keescook@chromium.org> Cc: Ard Biesheuvel <ardb@kernel.org> Cc: Pankaj Gupta <pankaj.gupta.linux@gmail.com> Cc: Baoquan He <bhe@redhat.com> Cc: Wei Yang <richardw.yang@linux.intel.com> Cc: Eric Biederman <ebiederm@xmission.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Anton Blanchard <anton@ozlabs.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com> Cc: Christian Borntraeger <borntraeger@de.ibm.com> Cc: Dave Jiang <dave.jiang@intel.com> Cc: Haiyang Zhang <haiyangz@microsoft.com> Cc: Heiko Carstens <hca@linux.ibm.com> Cc: Jason Wang <jasowang@redhat.com> Cc: Juergen Gross <jgross@suse.com> Cc: Julien Grall <julien@xen.org> Cc: "K. Y. Srinivasan" <kys@microsoft.com> Cc: Len Brown <lenb@kernel.org> Cc: Leonardo Bras <leobras.c@gmail.com> Cc: Libor Pechacek <lpechacek@suse.cz> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: "Michael S. Tsirkin" <mst@redhat.com> Cc: Nathan Lynch <nathanl@linux.ibm.com> Cc: "Oliver O'Halloran" <oohall@gmail.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Pingfan Liu <kernelfans@gmail.com> Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net> Cc: Roger Pau Monné <roger.pau@citrix.com> Cc: Stefano Stabellini <sstabellini@kernel.org> Cc: Stephen Hemminger <sthemmin@microsoft.com> Cc: Vasily Gorbik <gor@linux.ibm.com> Cc: Vishal Verma <vishal.l.verma@intel.com> Cc: Wei Liu <wei.liu@kernel.org> Link: https://lkml.kernel.org/r/20200911103459.10306-3-david@redhat.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-10-16 03:08:33 +00:00
if (res->flags & IORESOURCE_SYSRAM_DRIVER_MANAGED)
return 0;
if (sz < kbuf->memsz)
return 0;
if (end < kbuf->buf_min || start > kbuf->buf_max)
return 0;
/*
* Allocate memory top down with-in ram range. Otherwise bottom up
* allocation.
*/
if (kbuf->top_down)
return locate_mem_hole_top_down(start, end, kbuf);
return locate_mem_hole_bottom_up(start, end, kbuf);
}
mm: memblock: make keeping memblock memory opt-in rather than opt-out Most architectures do not need the memblock memory after the page allocator is initialized, but only few enable ARCH_DISCARD_MEMBLOCK in the arch Kconfig. Replacing ARCH_DISCARD_MEMBLOCK with ARCH_KEEP_MEMBLOCK and inverting the logic makes it clear which architectures actually use memblock after system initialization and skips the necessity to add ARCH_DISCARD_MEMBLOCK to the architectures that are still missing that option. Link: http://lkml.kernel.org/r/1556102150-32517-1-git-send-email-rppt@linux.ibm.com Signed-off-by: Mike Rapoport <rppt@linux.ibm.com> Acked-by: Michael Ellerman <mpe@ellerman.id.au> (powerpc) Cc: Russell King <linux@armlinux.org.uk> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will.deacon@arm.com> Cc: Richard Kuo <rkuo@codeaurora.org> Cc: Tony Luck <tony.luck@intel.com> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Paul Burton <paul.burton@mips.com> Cc: James Hogan <jhogan@kernel.org> Cc: Ley Foon Tan <lftan@altera.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Yoshinori Sato <ysato@users.sourceforge.jp> Cc: Rich Felker <dalias@libc.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: Borislav Petkov <bp@alien8.de> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Eric Biederman <ebiederm@xmission.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-05-14 00:22:59 +00:00
#ifdef CONFIG_ARCH_KEEP_MEMBLOCK
static int kexec_walk_memblock(struct kexec_buf *kbuf,
int (*func)(struct resource *, void *))
{
int ret = 0;
u64 i;
phys_addr_t mstart, mend;
struct resource res = { };
if (kbuf->image->type == KEXEC_TYPE_CRASH)
return func(&crashk_res, kbuf);
memblock: add MEMBLOCK_DRIVER_MANAGED to mimic IORESOURCE_SYSRAM_DRIVER_MANAGED Let's add a flag that corresponds to IORESOURCE_SYSRAM_DRIVER_MANAGED, indicating that we're dealing with a memory region that is never indicated in the firmware-provided memory map, but always detected and added by a driver. Similar to MEMBLOCK_HOTPLUG, most infrastructure has to treat such memory regions like ordinary MEMBLOCK_NONE memory regions -- for example, when selecting memory regions to add to the vmcore for dumping in the crashkernel via for_each_mem_range(). However, especially kexec_file is not supposed to select such memblocks via for_each_free_mem_range() / for_each_free_mem_range_reverse() to place kexec images, similar to how we handle IORESOURCE_SYSRAM_DRIVER_MANAGED without CONFIG_ARCH_KEEP_MEMBLOCK. We'll make sure that memory hotplug code sets the flag where applicable (IORESOURCE_SYSRAM_DRIVER_MANAGED) next. This prepares architectures that need CONFIG_ARCH_KEEP_MEMBLOCK, such as arm64, for virtio-mem support. Note that kexec *must not* indicate this memory to the second kernel and *must not* place kexec-images on this memory. Let's add a comment to kexec_walk_memblock(), documenting how we handle MEMBLOCK_DRIVER_MANAGED now just like using IORESOURCE_SYSRAM_DRIVER_MANAGED in locate_mem_hole_callback() for kexec_walk_resources(). Also note that MEMBLOCK_HOTPLUG cannot be reused due to different semantics: MEMBLOCK_HOTPLUG: memory is indicated as "System RAM" in the firmware-provided memory map and added to the system early during boot; kexec *has to* indicate this memory to the second kernel and can place kexec-images on this memory. After memory hotunplug, kexec has to be re-armed. We mostly ignore this flag when "movable_node" is not set on the kernel command line, because then we're told to not care about hotunpluggability of such memory regions. MEMBLOCK_DRIVER_MANAGED: memory is not indicated as "System RAM" in the firmware-provided memory map; this memory is always detected and added to the system by a driver; memory might not actually be physically hotunpluggable. kexec *must not* indicate this memory to the second kernel and *must not* place kexec-images on this memory. Link: https://lkml.kernel.org/r/20211004093605.5830-5-david@redhat.com Signed-off-by: David Hildenbrand <david@redhat.com> Reviewed-by: Mike Rapoport <rppt@linux.ibm.com> Cc: "Aneesh Kumar K . V" <aneesh.kumar@linux.ibm.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Christian Borntraeger <borntraeger@de.ibm.com> Cc: Eric Biederman <ebiederm@xmission.com> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Heiko Carstens <hca@linux.ibm.com> Cc: Huacai Chen <chenhuacai@kernel.org> Cc: Jianyong Wu <Jianyong.Wu@arm.com> Cc: Jiaxun Yang <jiaxun.yang@flygoat.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Oscar Salvador <osalvador@suse.de> Cc: Shahab Vahedi <shahab@synopsys.com> Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de> Cc: Vasily Gorbik <gor@linux.ibm.com> Cc: Vineet Gupta <vgupta@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-11-05 20:44:53 +00:00
/*
* Using MEMBLOCK_NONE will properly skip MEMBLOCK_DRIVER_MANAGED. See
* IORESOURCE_SYSRAM_DRIVER_MANAGED handling in
* locate_mem_hole_callback().
*/
if (kbuf->top_down) {
for_each_free_mem_range_reverse(i, NUMA_NO_NODE, MEMBLOCK_NONE,
&mstart, &mend, NULL) {
/*
* In memblock, end points to the first byte after the
* range while in kexec, end points to the last byte
* in the range.
*/
res.start = mstart;
res.end = mend - 1;
ret = func(&res, kbuf);
if (ret)
break;
}
} else {
for_each_free_mem_range(i, NUMA_NO_NODE, MEMBLOCK_NONE,
&mstart, &mend, NULL) {
/*
* In memblock, end points to the first byte after the
* range while in kexec, end points to the last byte
* in the range.
*/
res.start = mstart;
res.end = mend - 1;
ret = func(&res, kbuf);
if (ret)
break;
}
}
return ret;
}
mm: memblock: make keeping memblock memory opt-in rather than opt-out Most architectures do not need the memblock memory after the page allocator is initialized, but only few enable ARCH_DISCARD_MEMBLOCK in the arch Kconfig. Replacing ARCH_DISCARD_MEMBLOCK with ARCH_KEEP_MEMBLOCK and inverting the logic makes it clear which architectures actually use memblock after system initialization and skips the necessity to add ARCH_DISCARD_MEMBLOCK to the architectures that are still missing that option. Link: http://lkml.kernel.org/r/1556102150-32517-1-git-send-email-rppt@linux.ibm.com Signed-off-by: Mike Rapoport <rppt@linux.ibm.com> Acked-by: Michael Ellerman <mpe@ellerman.id.au> (powerpc) Cc: Russell King <linux@armlinux.org.uk> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will.deacon@arm.com> Cc: Richard Kuo <rkuo@codeaurora.org> Cc: Tony Luck <tony.luck@intel.com> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Paul Burton <paul.burton@mips.com> Cc: James Hogan <jhogan@kernel.org> Cc: Ley Foon Tan <lftan@altera.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Yoshinori Sato <ysato@users.sourceforge.jp> Cc: Rich Felker <dalias@libc.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: Borislav Petkov <bp@alien8.de> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Eric Biederman <ebiederm@xmission.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-05-14 00:22:59 +00:00
#else
static int kexec_walk_memblock(struct kexec_buf *kbuf,
int (*func)(struct resource *, void *))
{
return 0;
}
#endif
/**
* kexec_walk_resources - call func(data) on free memory regions
* @kbuf: Context info for the search. Also passed to @func.
* @func: Function to call for each memory region.
*
* Return: The memory walk will stop when func returns a non-zero value
* and that value will be returned. If all free regions are visited without
* func returning non-zero, then zero will be returned.
*/
static int kexec_walk_resources(struct kexec_buf *kbuf,
int (*func)(struct resource *, void *))
{
if (kbuf->image->type == KEXEC_TYPE_CRASH)
return walk_iomem_res_desc(crashk_res.desc,
IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY,
crashk_res.start, crashk_res.end,
kbuf, func);
else
return walk_system_ram_res(0, ULONG_MAX, kbuf, func);
}
/**
* kexec_locate_mem_hole - find free memory for the purgatory or the next kernel
* @kbuf: Parameters for the memory search.
*
* On success, kbuf->mem will have the start address of the memory region found.
*
* Return: 0 on success, negative errno on error.
*/
int kexec_locate_mem_hole(struct kexec_buf *kbuf)
{
int ret;
/* Arch knows where to place */
if (kbuf->mem != KEXEC_BUF_MEM_UNKNOWN)
return 0;
mm: memblock: make keeping memblock memory opt-in rather than opt-out Most architectures do not need the memblock memory after the page allocator is initialized, but only few enable ARCH_DISCARD_MEMBLOCK in the arch Kconfig. Replacing ARCH_DISCARD_MEMBLOCK with ARCH_KEEP_MEMBLOCK and inverting the logic makes it clear which architectures actually use memblock after system initialization and skips the necessity to add ARCH_DISCARD_MEMBLOCK to the architectures that are still missing that option. Link: http://lkml.kernel.org/r/1556102150-32517-1-git-send-email-rppt@linux.ibm.com Signed-off-by: Mike Rapoport <rppt@linux.ibm.com> Acked-by: Michael Ellerman <mpe@ellerman.id.au> (powerpc) Cc: Russell King <linux@armlinux.org.uk> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will.deacon@arm.com> Cc: Richard Kuo <rkuo@codeaurora.org> Cc: Tony Luck <tony.luck@intel.com> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Paul Burton <paul.burton@mips.com> Cc: James Hogan <jhogan@kernel.org> Cc: Ley Foon Tan <lftan@altera.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Yoshinori Sato <ysato@users.sourceforge.jp> Cc: Rich Felker <dalias@libc.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: Borislav Petkov <bp@alien8.de> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Eric Biederman <ebiederm@xmission.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-05-14 00:22:59 +00:00
if (!IS_ENABLED(CONFIG_ARCH_KEEP_MEMBLOCK))
ret = kexec_walk_resources(kbuf, locate_mem_hole_callback);
else
ret = kexec_walk_memblock(kbuf, locate_mem_hole_callback);
return ret == 1 ? 0 : -EADDRNOTAVAIL;
}
/**
* arch_kexec_locate_mem_hole - Find free memory to place the segments.
* @kbuf: Parameters for the memory search.
*
* On success, kbuf->mem will have the start address of the memory region found.
*
* Return: 0 on success, negative errno on error.
*/
int __weak arch_kexec_locate_mem_hole(struct kexec_buf *kbuf)
{
return kexec_locate_mem_hole(kbuf);
}
/**
* kexec_add_buffer - place a buffer in a kexec segment
* @kbuf: Buffer contents and memory parameters.
*
* This function assumes that kexec_mutex is held.
* On successful return, @kbuf->mem will have the physical address of
* the buffer in memory.
*
* Return: 0 on success, negative errno on error.
*/
int kexec_add_buffer(struct kexec_buf *kbuf)
{
struct kexec_segment *ksegment;
int ret;
/* Currently adding segment this way is allowed only in file mode */
if (!kbuf->image->file_mode)
return -EINVAL;
if (kbuf->image->nr_segments >= KEXEC_SEGMENT_MAX)
return -EINVAL;
/*
* Make sure we are not trying to add buffer after allocating
* control pages. All segments need to be placed first before
* any control pages are allocated. As control page allocation
* logic goes through list of segments to make sure there are
* no destination overlaps.
*/
if (!list_empty(&kbuf->image->control_pages)) {
WARN_ON(1);
return -EINVAL;
}
/* Ensure minimum alignment needed for segments. */
kbuf->memsz = ALIGN(kbuf->memsz, PAGE_SIZE);
kbuf->buf_align = max(kbuf->buf_align, PAGE_SIZE);
/* Walk the RAM ranges and allocate a suitable range for the buffer */
ret = arch_kexec_locate_mem_hole(kbuf);
if (ret)
return ret;
/* Found a suitable memory range */
ksegment = &kbuf->image->segment[kbuf->image->nr_segments];
ksegment->kbuf = kbuf->buffer;
ksegment->bufsz = kbuf->bufsz;
ksegment->mem = kbuf->mem;
ksegment->memsz = kbuf->memsz;
kbuf->image->nr_segments++;
return 0;
}
/* Calculate and store the digest of segments */
static int kexec_calculate_store_digests(struct kimage *image)
{
struct crypto_shash *tfm;
struct shash_desc *desc;
int ret = 0, i, j, zero_buf_sz, sha_region_sz;
size_t desc_size, nullsz;
char *digest;
void *zero_buf;
struct kexec_sha_region *sha_regions;
struct purgatory_info *pi = &image->purgatory_info;
kexec_file: make use of purgatory optional Patch series "kexec_file, x86, powerpc: refactoring for other architecutres", v2. This is a preparatory patchset for adding kexec_file support on arm64. It was originally included in a arm64 patch set[1], but Philipp is also working on their kexec_file support on s390[2] and some changes are now conflicting. So these common parts were extracted and put into a separate patch set for better integration. What's more, my original patch#4 was split into a few small chunks for easier review after Dave's comment. As such, the resulting code is basically identical with my original, and the only *visible* differences are: - renaming of _kexec_kernel_image_probe() and _kimage_file_post_load_cleanup() - change one of types of arguments at prepare_elf64_headers() Those, unfortunately, require a couple of trivial changes on the rest (#1, #6 to #13) of my arm64 kexec_file patch set[1]. Patch #1 allows making a use of purgatory optional, particularly useful for arm64. Patch #2 commonalizes arch_kexec_kernel_{image_probe, image_load, verify_sig}() and arch_kimage_file_post_load_cleanup() across architectures. Patches #3-#7 are also intended to generalize parse_elf64_headers(), along with exclude_mem_range(), to be made best re-use of. [1] http://lists.infradead.org/pipermail/linux-arm-kernel/2018-February/561182.html [2] http://lkml.iu.edu//hypermail/linux/kernel/1802.1/02596.html This patch (of 7): On arm64, crash dump kernel's usable memory is protected by *unmapping* it from kernel virtual space unlike other architectures where the region is just made read-only. It is highly unlikely that the region is accidentally corrupted and this observation rationalizes that digest check code can also be dropped from purgatory. The resulting code is so simple as it doesn't require a bit ugly re-linking/relocation stuff, i.e. arch_kexec_apply_relocations_add(). Please see: http://lists.infradead.org/pipermail/linux-arm-kernel/2017-December/545428.html All that the purgatory does is to shuffle arguments and jump into a new kernel, while we still need to have some space for a hash value (purgatory_sha256_digest) which is never checked against. As such, it doesn't make sense to have trampline code between old kernel and new kernel on arm64. This patch introduces a new configuration, ARCH_HAS_KEXEC_PURGATORY, and allows related code to be compiled in only if necessary. [takahiro.akashi@linaro.org: fix trivial screwup] Link: http://lkml.kernel.org/r/20180309093346.GF25863@linaro.org Link: http://lkml.kernel.org/r/20180306102303.9063-2-takahiro.akashi@linaro.org Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org> Acked-by: Dave Young <dyoung@redhat.com> Tested-by: Dave Young <dyoung@redhat.com> Cc: Vivek Goyal <vgoyal@redhat.com> Cc: Baoquan He <bhe@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-04-13 22:35:45 +00:00
if (!IS_ENABLED(CONFIG_ARCH_HAS_KEXEC_PURGATORY))
return 0;
zero_buf = __va(page_to_pfn(ZERO_PAGE(0)) << PAGE_SHIFT);
zero_buf_sz = PAGE_SIZE;
tfm = crypto_alloc_shash("sha256", 0, 0);
if (IS_ERR(tfm)) {
ret = PTR_ERR(tfm);
goto out;
}
desc_size = crypto_shash_descsize(tfm) + sizeof(*desc);
desc = kzalloc(desc_size, GFP_KERNEL);
if (!desc) {
ret = -ENOMEM;
goto out_free_tfm;
}
sha_region_sz = KEXEC_SEGMENT_MAX * sizeof(struct kexec_sha_region);
sha_regions = vzalloc(sha_region_sz);
if (!sha_regions) {
ret = -ENOMEM;
goto out_free_desc;
}
desc->tfm = tfm;
ret = crypto_shash_init(desc);
if (ret < 0)
goto out_free_sha_regions;
digest = kzalloc(SHA256_DIGEST_SIZE, GFP_KERNEL);
if (!digest) {
ret = -ENOMEM;
goto out_free_sha_regions;
}
for (j = i = 0; i < image->nr_segments; i++) {
struct kexec_segment *ksegment;
ksegment = &image->segment[i];
/*
* Skip purgatory as it will be modified once we put digest
* info in purgatory.
*/
if (ksegment->kbuf == pi->purgatory_buf)
continue;
ret = crypto_shash_update(desc, ksegment->kbuf,
ksegment->bufsz);
if (ret)
break;
/*
* Assume rest of the buffer is filled with zero and
* update digest accordingly.
*/
nullsz = ksegment->memsz - ksegment->bufsz;
while (nullsz) {
unsigned long bytes = nullsz;
if (bytes > zero_buf_sz)
bytes = zero_buf_sz;
ret = crypto_shash_update(desc, zero_buf, bytes);
if (ret)
break;
nullsz -= bytes;
}
if (ret)
break;
sha_regions[j].start = ksegment->mem;
sha_regions[j].len = ksegment->memsz;
j++;
}
if (!ret) {
ret = crypto_shash_final(desc, digest);
if (ret)
goto out_free_digest;
kexec, x86/purgatory: Unbreak it and clean it up The purgatory code defines global variables which are referenced via a symbol lookup in the kexec code (core and arch). A recent commit addressing sparse warnings made these static and thereby broke kexec_file. Why did this happen? Simply because the whole machinery is undocumented and lacks any form of forward declarations. The variable names are unspecific and lack a prefix, so adding forward declarations creates shadow variables in the core code. Aside of that the code relies on magic constants and duplicate struct definitions with no way to ensure that these things stay in sync. The section placement of the purgatory variables happened by chance and not by design. Unbreak kexec and cleanup the mess: - Add proper forward declarations and document the usage - Use common struct definition - Use the proper common defines instead of magic constants - Add a purgatory_ prefix to have a proper name space - Use ARRAY_SIZE() instead of a homebrewn reimplementation - Add proper sections to the purgatory variables [ From Mike ] Fixes: 72042a8c7b01 ("x86/purgatory: Make functions and variables static") Reported-by: Mike Galbraith <<efault@gmx.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Nicholas Mc Guire <der.herr@hofr.at> Cc: Borislav Petkov <bp@alien8.de> Cc: Vivek Goyal <vgoyal@redhat.com> Cc: "Tobin C. Harding" <me@tobin.cc> Link: http://lkml.kernel.org/r/alpine.DEB.2.20.1703101315140.3681@nanos Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2017-03-10 12:17:18 +00:00
ret = kexec_purgatory_get_set_symbol(image, "purgatory_sha_regions",
sha_regions, sha_region_sz, 0);
if (ret)
goto out_free_digest;
kexec, x86/purgatory: Unbreak it and clean it up The purgatory code defines global variables which are referenced via a symbol lookup in the kexec code (core and arch). A recent commit addressing sparse warnings made these static and thereby broke kexec_file. Why did this happen? Simply because the whole machinery is undocumented and lacks any form of forward declarations. The variable names are unspecific and lack a prefix, so adding forward declarations creates shadow variables in the core code. Aside of that the code relies on magic constants and duplicate struct definitions with no way to ensure that these things stay in sync. The section placement of the purgatory variables happened by chance and not by design. Unbreak kexec and cleanup the mess: - Add proper forward declarations and document the usage - Use common struct definition - Use the proper common defines instead of magic constants - Add a purgatory_ prefix to have a proper name space - Use ARRAY_SIZE() instead of a homebrewn reimplementation - Add proper sections to the purgatory variables [ From Mike ] Fixes: 72042a8c7b01 ("x86/purgatory: Make functions and variables static") Reported-by: Mike Galbraith <<efault@gmx.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Nicholas Mc Guire <der.herr@hofr.at> Cc: Borislav Petkov <bp@alien8.de> Cc: Vivek Goyal <vgoyal@redhat.com> Cc: "Tobin C. Harding" <me@tobin.cc> Link: http://lkml.kernel.org/r/alpine.DEB.2.20.1703101315140.3681@nanos Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2017-03-10 12:17:18 +00:00
ret = kexec_purgatory_get_set_symbol(image, "purgatory_sha256_digest",
digest, SHA256_DIGEST_SIZE, 0);
if (ret)
goto out_free_digest;
}
out_free_digest:
kfree(digest);
out_free_sha_regions:
vfree(sha_regions);
out_free_desc:
kfree(desc);
out_free_tfm:
kfree(tfm);
out:
return ret;
}
kexec_file: make use of purgatory optional Patch series "kexec_file, x86, powerpc: refactoring for other architecutres", v2. This is a preparatory patchset for adding kexec_file support on arm64. It was originally included in a arm64 patch set[1], but Philipp is also working on their kexec_file support on s390[2] and some changes are now conflicting. So these common parts were extracted and put into a separate patch set for better integration. What's more, my original patch#4 was split into a few small chunks for easier review after Dave's comment. As such, the resulting code is basically identical with my original, and the only *visible* differences are: - renaming of _kexec_kernel_image_probe() and _kimage_file_post_load_cleanup() - change one of types of arguments at prepare_elf64_headers() Those, unfortunately, require a couple of trivial changes on the rest (#1, #6 to #13) of my arm64 kexec_file patch set[1]. Patch #1 allows making a use of purgatory optional, particularly useful for arm64. Patch #2 commonalizes arch_kexec_kernel_{image_probe, image_load, verify_sig}() and arch_kimage_file_post_load_cleanup() across architectures. Patches #3-#7 are also intended to generalize parse_elf64_headers(), along with exclude_mem_range(), to be made best re-use of. [1] http://lists.infradead.org/pipermail/linux-arm-kernel/2018-February/561182.html [2] http://lkml.iu.edu//hypermail/linux/kernel/1802.1/02596.html This patch (of 7): On arm64, crash dump kernel's usable memory is protected by *unmapping* it from kernel virtual space unlike other architectures where the region is just made read-only. It is highly unlikely that the region is accidentally corrupted and this observation rationalizes that digest check code can also be dropped from purgatory. The resulting code is so simple as it doesn't require a bit ugly re-linking/relocation stuff, i.e. arch_kexec_apply_relocations_add(). Please see: http://lists.infradead.org/pipermail/linux-arm-kernel/2017-December/545428.html All that the purgatory does is to shuffle arguments and jump into a new kernel, while we still need to have some space for a hash value (purgatory_sha256_digest) which is never checked against. As such, it doesn't make sense to have trampline code between old kernel and new kernel on arm64. This patch introduces a new configuration, ARCH_HAS_KEXEC_PURGATORY, and allows related code to be compiled in only if necessary. [takahiro.akashi@linaro.org: fix trivial screwup] Link: http://lkml.kernel.org/r/20180309093346.GF25863@linaro.org Link: http://lkml.kernel.org/r/20180306102303.9063-2-takahiro.akashi@linaro.org Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org> Acked-by: Dave Young <dyoung@redhat.com> Tested-by: Dave Young <dyoung@redhat.com> Cc: Vivek Goyal <vgoyal@redhat.com> Cc: Baoquan He <bhe@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-04-13 22:35:45 +00:00
#ifdef CONFIG_ARCH_HAS_KEXEC_PURGATORY
/*
* kexec_purgatory_setup_kbuf - prepare buffer to load purgatory.
* @pi: Purgatory to be loaded.
* @kbuf: Buffer to setup.
*
* Allocates the memory needed for the buffer. Caller is responsible to free
* the memory after use.
*
* Return: 0 on success, negative errno on error.
*/
static int kexec_purgatory_setup_kbuf(struct purgatory_info *pi,
struct kexec_buf *kbuf)
{
const Elf_Shdr *sechdrs;
unsigned long bss_align;
unsigned long bss_sz;
unsigned long align;
int i, ret;
sechdrs = (void *)pi->ehdr + pi->ehdr->e_shoff;
kernel/kexec_file.c: allow archs to set purgatory load address For s390 new kernels are loaded to fixed addresses in memory before they are booted. With the current code this is a problem as it assumes the kernel will be loaded to an 'arbitrary' address. In particular, kexec_locate_mem_hole searches for a large enough memory region and sets the load address (kexec_bufer->mem) to it. Luckily there is a simple workaround for this problem. By returning 1 in arch_kexec_walk_mem, kexec_locate_mem_hole is turned off. This allows the architecture to set kbuf->mem by hand. While the trick works fine for the kernel it does not for the purgatory as here the architectures don't have access to its kexec_buffer. Give architectures access to the purgatories kexec_buffer by changing kexec_load_purgatory to take a pointer to it. With this change architectures have access to the buffer and can edit it as they need. A nice side effect of this change is that we can get rid of the purgatory_info->purgatory_load_address field. As now the information stored there can directly be accessed from kbuf->mem. Link: http://lkml.kernel.org/r/20180321112751.22196-11-prudo@linux.vnet.ibm.com Signed-off-by: Philipp Rudo <prudo@linux.vnet.ibm.com> Reviewed-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Acked-by: Dave Young <dyoung@redhat.com> Cc: AKASHI Takahiro <takahiro.akashi@linaro.org> Cc: Eric Biederman <ebiederm@xmission.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com> Cc: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-04-13 22:36:43 +00:00
kbuf->buf_align = bss_align = 1;
kbuf->bufsz = bss_sz = 0;
for (i = 0; i < pi->ehdr->e_shnum; i++) {
if (!(sechdrs[i].sh_flags & SHF_ALLOC))
continue;
align = sechdrs[i].sh_addralign;
if (sechdrs[i].sh_type != SHT_NOBITS) {
if (kbuf->buf_align < align)
kbuf->buf_align = align;
kbuf->bufsz = ALIGN(kbuf->bufsz, align);
kbuf->bufsz += sechdrs[i].sh_size;
} else {
if (bss_align < align)
bss_align = align;
bss_sz = ALIGN(bss_sz, align);
bss_sz += sechdrs[i].sh_size;
}
}
kbuf->bufsz = ALIGN(kbuf->bufsz, bss_align);
kbuf->memsz = kbuf->bufsz + bss_sz;
if (kbuf->buf_align < bss_align)
kbuf->buf_align = bss_align;
kbuf->buffer = vzalloc(kbuf->bufsz);
if (!kbuf->buffer)
return -ENOMEM;
pi->purgatory_buf = kbuf->buffer;
ret = kexec_add_buffer(kbuf);
if (ret)
goto out;
return 0;
out:
vfree(pi->purgatory_buf);
pi->purgatory_buf = NULL;
return ret;
}
/*
* kexec_purgatory_setup_sechdrs - prepares the pi->sechdrs buffer.
* @pi: Purgatory to be loaded.
* @kbuf: Buffer prepared to store purgatory.
*
* Allocates the memory needed for the buffer. Caller is responsible to free
* the memory after use.
*
* Return: 0 on success, negative errno on error.
*/
static int kexec_purgatory_setup_sechdrs(struct purgatory_info *pi,
struct kexec_buf *kbuf)
{
unsigned long bss_addr;
unsigned long offset;
Elf_Shdr *sechdrs;
int i;
/*
* The section headers in kexec_purgatory are read-only. In order to
* have them modifiable make a temporary copy.
*/
treewide: Use array_size() in vzalloc() The vzalloc() function has no 2-factor argument form, so multiplication factors need to be wrapped in array_size(). This patch replaces cases of: vzalloc(a * b) with: vzalloc(array_size(a, b)) as well as handling cases of: vzalloc(a * b * c) with: vzalloc(array3_size(a, b, c)) This does, however, attempt to ignore constant size factors like: vzalloc(4 * 1024) though any constants defined via macros get caught up in the conversion. Any factors with a sizeof() of "unsigned char", "char", and "u8" were dropped, since they're redundant. The Coccinelle script used for this was: // Fix redundant parens around sizeof(). @@ type TYPE; expression THING, E; @@ ( vzalloc( - (sizeof(TYPE)) * E + sizeof(TYPE) * E , ...) | vzalloc( - (sizeof(THING)) * E + sizeof(THING) * E , ...) ) // Drop single-byte sizes and redundant parens. @@ expression COUNT; typedef u8; typedef __u8; @@ ( vzalloc( - sizeof(u8) * (COUNT) + COUNT , ...) | vzalloc( - sizeof(__u8) * (COUNT) + COUNT , ...) | vzalloc( - sizeof(char) * (COUNT) + COUNT , ...) | vzalloc( - sizeof(unsigned char) * (COUNT) + COUNT , ...) | vzalloc( - sizeof(u8) * COUNT + COUNT , ...) | vzalloc( - sizeof(__u8) * COUNT + COUNT , ...) | vzalloc( - sizeof(char) * COUNT + COUNT , ...) | vzalloc( - sizeof(unsigned char) * COUNT + COUNT , ...) ) // 2-factor product with sizeof(type/expression) and identifier or constant. @@ type TYPE; expression THING; identifier COUNT_ID; constant COUNT_CONST; @@ ( vzalloc( - sizeof(TYPE) * (COUNT_ID) + array_size(COUNT_ID, sizeof(TYPE)) , ...) | vzalloc( - sizeof(TYPE) * COUNT_ID + array_size(COUNT_ID, sizeof(TYPE)) , ...) | vzalloc( - sizeof(TYPE) * (COUNT_CONST) + array_size(COUNT_CONST, sizeof(TYPE)) , ...) | vzalloc( - sizeof(TYPE) * COUNT_CONST + array_size(COUNT_CONST, sizeof(TYPE)) , ...) | vzalloc( - sizeof(THING) * (COUNT_ID) + array_size(COUNT_ID, sizeof(THING)) , ...) | vzalloc( - sizeof(THING) * COUNT_ID + array_size(COUNT_ID, sizeof(THING)) , ...) | vzalloc( - sizeof(THING) * (COUNT_CONST) + array_size(COUNT_CONST, sizeof(THING)) , ...) | vzalloc( - sizeof(THING) * COUNT_CONST + array_size(COUNT_CONST, sizeof(THING)) , ...) ) // 2-factor product, only identifiers. @@ identifier SIZE, COUNT; @@ vzalloc( - SIZE * COUNT + array_size(COUNT, SIZE) , ...) // 3-factor product with 1 sizeof(type) or sizeof(expression), with // redundant parens removed. @@ expression THING; identifier STRIDE, COUNT; type TYPE; @@ ( vzalloc( - sizeof(TYPE) * (COUNT) * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | vzalloc( - sizeof(TYPE) * (COUNT) * STRIDE + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | vzalloc( - sizeof(TYPE) * COUNT * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | vzalloc( - sizeof(TYPE) * COUNT * STRIDE + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | vzalloc( - sizeof(THING) * (COUNT) * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) | vzalloc( - sizeof(THING) * (COUNT) * STRIDE + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) | vzalloc( - sizeof(THING) * COUNT * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) | vzalloc( - sizeof(THING) * COUNT * STRIDE + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) ) // 3-factor product with 2 sizeof(variable), with redundant parens removed. @@ expression THING1, THING2; identifier COUNT; type TYPE1, TYPE2; @@ ( vzalloc( - sizeof(TYPE1) * sizeof(TYPE2) * COUNT + array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2)) , ...) | vzalloc( - sizeof(TYPE1) * sizeof(THING2) * (COUNT) + array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2)) , ...) | vzalloc( - sizeof(THING1) * sizeof(THING2) * COUNT + array3_size(COUNT, sizeof(THING1), sizeof(THING2)) , ...) | vzalloc( - sizeof(THING1) * sizeof(THING2) * (COUNT) + array3_size(COUNT, sizeof(THING1), sizeof(THING2)) , ...) | vzalloc( - sizeof(TYPE1) * sizeof(THING2) * COUNT + array3_size(COUNT, sizeof(TYPE1), sizeof(THING2)) , ...) | vzalloc( - sizeof(TYPE1) * sizeof(THING2) * (COUNT) + array3_size(COUNT, sizeof(TYPE1), sizeof(THING2)) , ...) ) // 3-factor product, only identifiers, with redundant parens removed. @@ identifier STRIDE, SIZE, COUNT; @@ ( vzalloc( - (COUNT) * STRIDE * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) | vzalloc( - COUNT * (STRIDE) * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) | vzalloc( - COUNT * STRIDE * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | vzalloc( - (COUNT) * (STRIDE) * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) | vzalloc( - COUNT * (STRIDE) * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | vzalloc( - (COUNT) * STRIDE * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | vzalloc( - (COUNT) * (STRIDE) * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | vzalloc( - COUNT * STRIDE * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) ) // Any remaining multi-factor products, first at least 3-factor products // when they're not all constants... @@ expression E1, E2, E3; constant C1, C2, C3; @@ ( vzalloc(C1 * C2 * C3, ...) | vzalloc( - E1 * E2 * E3 + array3_size(E1, E2, E3) , ...) ) // And then all remaining 2 factors products when they're not all constants. @@ expression E1, E2; constant C1, C2; @@ ( vzalloc(C1 * C2, ...) | vzalloc( - E1 * E2 + array_size(E1, E2) , ...) ) Signed-off-by: Kees Cook <keescook@chromium.org>
2018-06-12 21:27:37 +00:00
sechdrs = vzalloc(array_size(sizeof(Elf_Shdr), pi->ehdr->e_shnum));
if (!sechdrs)
return -ENOMEM;
memcpy(sechdrs, (void *)pi->ehdr + pi->ehdr->e_shoff,
pi->ehdr->e_shnum * sizeof(Elf_Shdr));
pi->sechdrs = sechdrs;
offset = 0;
bss_addr = kbuf->mem + kbuf->bufsz;
kbuf->image->start = pi->ehdr->e_entry;
for (i = 0; i < pi->ehdr->e_shnum; i++) {
unsigned long align;
void *src, *dst;
if (!(sechdrs[i].sh_flags & SHF_ALLOC))
continue;
align = sechdrs[i].sh_addralign;
if (sechdrs[i].sh_type == SHT_NOBITS) {
bss_addr = ALIGN(bss_addr, align);
sechdrs[i].sh_addr = bss_addr;
bss_addr += sechdrs[i].sh_size;
continue;
}
offset = ALIGN(offset, align);
if (sechdrs[i].sh_flags & SHF_EXECINSTR &&
pi->ehdr->e_entry >= sechdrs[i].sh_addr &&
pi->ehdr->e_entry < (sechdrs[i].sh_addr
+ sechdrs[i].sh_size)) {
kbuf->image->start -= sechdrs[i].sh_addr;
kbuf->image->start += kbuf->mem + offset;
}
src = (void *)pi->ehdr + sechdrs[i].sh_offset;
dst = pi->purgatory_buf + offset;
memcpy(dst, src, sechdrs[i].sh_size);
sechdrs[i].sh_addr = kbuf->mem + offset;
sechdrs[i].sh_offset = offset;
offset += sechdrs[i].sh_size;
}
return 0;
}
static int kexec_apply_relocations(struct kimage *image)
{
int i, ret;
struct purgatory_info *pi = &image->purgatory_info;
const Elf_Shdr *sechdrs;
sechdrs = (void *)pi->ehdr + pi->ehdr->e_shoff;
for (i = 0; i < pi->ehdr->e_shnum; i++) {
const Elf_Shdr *relsec;
const Elf_Shdr *symtab;
Elf_Shdr *section;
relsec = sechdrs + i;
if (relsec->sh_type != SHT_RELA &&
relsec->sh_type != SHT_REL)
continue;
/*
* For section of type SHT_RELA/SHT_REL,
* ->sh_link contains section header index of associated
* symbol table. And ->sh_info contains section header
* index of section to which relocations apply.
*/
if (relsec->sh_info >= pi->ehdr->e_shnum ||
relsec->sh_link >= pi->ehdr->e_shnum)
return -ENOEXEC;
section = pi->sechdrs + relsec->sh_info;
symtab = sechdrs + relsec->sh_link;
if (!(section->sh_flags & SHF_ALLOC))
continue;
/*
* symtab->sh_link contain section header index of associated
* string table.
*/
if (symtab->sh_link >= pi->ehdr->e_shnum)
/* Invalid section number? */
continue;
/*
* Respective architecture needs to provide support for applying
* relocations of type SHT_RELA/SHT_REL.
*/
if (relsec->sh_type == SHT_RELA)
ret = arch_kexec_apply_relocations_add(pi, section,
relsec, symtab);
else if (relsec->sh_type == SHT_REL)
ret = arch_kexec_apply_relocations(pi, section,
relsec, symtab);
if (ret)
return ret;
}
return 0;
}
kernel/kexec_file.c: allow archs to set purgatory load address For s390 new kernels are loaded to fixed addresses in memory before they are booted. With the current code this is a problem as it assumes the kernel will be loaded to an 'arbitrary' address. In particular, kexec_locate_mem_hole searches for a large enough memory region and sets the load address (kexec_bufer->mem) to it. Luckily there is a simple workaround for this problem. By returning 1 in arch_kexec_walk_mem, kexec_locate_mem_hole is turned off. This allows the architecture to set kbuf->mem by hand. While the trick works fine for the kernel it does not for the purgatory as here the architectures don't have access to its kexec_buffer. Give architectures access to the purgatories kexec_buffer by changing kexec_load_purgatory to take a pointer to it. With this change architectures have access to the buffer and can edit it as they need. A nice side effect of this change is that we can get rid of the purgatory_info->purgatory_load_address field. As now the information stored there can directly be accessed from kbuf->mem. Link: http://lkml.kernel.org/r/20180321112751.22196-11-prudo@linux.vnet.ibm.com Signed-off-by: Philipp Rudo <prudo@linux.vnet.ibm.com> Reviewed-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Acked-by: Dave Young <dyoung@redhat.com> Cc: AKASHI Takahiro <takahiro.akashi@linaro.org> Cc: Eric Biederman <ebiederm@xmission.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com> Cc: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-04-13 22:36:43 +00:00
/*
* kexec_load_purgatory - Load and relocate the purgatory object.
* @image: Image to add the purgatory to.
* @kbuf: Memory parameters to use.
*
* Allocates the memory needed for image->purgatory_info.sechdrs and
* image->purgatory_info.purgatory_buf/kbuf->buffer. Caller is responsible
* to free the memory after use.
*
* Return: 0 on success, negative errno on error.
*/
int kexec_load_purgatory(struct kimage *image, struct kexec_buf *kbuf)
{
struct purgatory_info *pi = &image->purgatory_info;
int ret;
if (kexec_purgatory_size <= 0)
return -EINVAL;
pi->ehdr = (const Elf_Ehdr *)kexec_purgatory;
kernel/kexec_file.c: allow archs to set purgatory load address For s390 new kernels are loaded to fixed addresses in memory before they are booted. With the current code this is a problem as it assumes the kernel will be loaded to an 'arbitrary' address. In particular, kexec_locate_mem_hole searches for a large enough memory region and sets the load address (kexec_bufer->mem) to it. Luckily there is a simple workaround for this problem. By returning 1 in arch_kexec_walk_mem, kexec_locate_mem_hole is turned off. This allows the architecture to set kbuf->mem by hand. While the trick works fine for the kernel it does not for the purgatory as here the architectures don't have access to its kexec_buffer. Give architectures access to the purgatories kexec_buffer by changing kexec_load_purgatory to take a pointer to it. With this change architectures have access to the buffer and can edit it as they need. A nice side effect of this change is that we can get rid of the purgatory_info->purgatory_load_address field. As now the information stored there can directly be accessed from kbuf->mem. Link: http://lkml.kernel.org/r/20180321112751.22196-11-prudo@linux.vnet.ibm.com Signed-off-by: Philipp Rudo <prudo@linux.vnet.ibm.com> Reviewed-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Acked-by: Dave Young <dyoung@redhat.com> Cc: AKASHI Takahiro <takahiro.akashi@linaro.org> Cc: Eric Biederman <ebiederm@xmission.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com> Cc: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-04-13 22:36:43 +00:00
ret = kexec_purgatory_setup_kbuf(pi, kbuf);
if (ret)
return ret;
kernel/kexec_file.c: allow archs to set purgatory load address For s390 new kernels are loaded to fixed addresses in memory before they are booted. With the current code this is a problem as it assumes the kernel will be loaded to an 'arbitrary' address. In particular, kexec_locate_mem_hole searches for a large enough memory region and sets the load address (kexec_bufer->mem) to it. Luckily there is a simple workaround for this problem. By returning 1 in arch_kexec_walk_mem, kexec_locate_mem_hole is turned off. This allows the architecture to set kbuf->mem by hand. While the trick works fine for the kernel it does not for the purgatory as here the architectures don't have access to its kexec_buffer. Give architectures access to the purgatories kexec_buffer by changing kexec_load_purgatory to take a pointer to it. With this change architectures have access to the buffer and can edit it as they need. A nice side effect of this change is that we can get rid of the purgatory_info->purgatory_load_address field. As now the information stored there can directly be accessed from kbuf->mem. Link: http://lkml.kernel.org/r/20180321112751.22196-11-prudo@linux.vnet.ibm.com Signed-off-by: Philipp Rudo <prudo@linux.vnet.ibm.com> Reviewed-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Acked-by: Dave Young <dyoung@redhat.com> Cc: AKASHI Takahiro <takahiro.akashi@linaro.org> Cc: Eric Biederman <ebiederm@xmission.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com> Cc: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-04-13 22:36:43 +00:00
ret = kexec_purgatory_setup_sechdrs(pi, kbuf);
if (ret)
goto out_free_kbuf;
ret = kexec_apply_relocations(image);
if (ret)
goto out;
return 0;
out:
vfree(pi->sechdrs);
kexec: fix double-free when failing to relocate the purgatory If kexec_apply_relocations fails, kexec_load_purgatory frees pi->sechdrs and pi->purgatory_buf. This is redundant, because in case of error kimage_file_prepare_segments calls kimage_file_post_load_cleanup, which will also free those buffers. This causes two warnings like the following, one for pi->sechdrs and the other for pi->purgatory_buf: kexec-bzImage64: Loading purgatory failed ------------[ cut here ]------------ WARNING: CPU: 1 PID: 2119 at mm/vmalloc.c:1490 __vunmap+0xc1/0xd0 Trying to vfree() nonexistent vm area (ffffc90000e91000) Modules linked in: CPU: 1 PID: 2119 Comm: kexec Not tainted 4.8.0-rc3+ #5 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011 Call Trace: dump_stack+0x4d/0x65 __warn+0xcb/0xf0 warn_slowpath_fmt+0x4f/0x60 ? find_vmap_area+0x19/0x70 ? kimage_file_post_load_cleanup+0x47/0xb0 __vunmap+0xc1/0xd0 vfree+0x2e/0x70 kimage_file_post_load_cleanup+0x5e/0xb0 SyS_kexec_file_load+0x448/0x680 ? putname+0x54/0x60 ? do_sys_open+0x190/0x1f0 entry_SYSCALL_64_fastpath+0x13/0x8f ---[ end trace 158bb74f5950ca2b ]--- Fix by setting pi->sechdrs an pi->purgatory_buf to NULL, since vfree won't try to free a NULL pointer. Link: http://lkml.kernel.org/r/1472083546-23683-1-git-send-email-bauerman@linux.vnet.ibm.com Signed-off-by: Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com> Acked-by: Baoquan He <bhe@redhat.com> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Vivek Goyal <vgoyal@redhat.com> Cc: Dave Young <dyoung@redhat.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-09-01 23:14:44 +00:00
pi->sechdrs = NULL;
out_free_kbuf:
vfree(pi->purgatory_buf);
kexec: fix double-free when failing to relocate the purgatory If kexec_apply_relocations fails, kexec_load_purgatory frees pi->sechdrs and pi->purgatory_buf. This is redundant, because in case of error kimage_file_prepare_segments calls kimage_file_post_load_cleanup, which will also free those buffers. This causes two warnings like the following, one for pi->sechdrs and the other for pi->purgatory_buf: kexec-bzImage64: Loading purgatory failed ------------[ cut here ]------------ WARNING: CPU: 1 PID: 2119 at mm/vmalloc.c:1490 __vunmap+0xc1/0xd0 Trying to vfree() nonexistent vm area (ffffc90000e91000) Modules linked in: CPU: 1 PID: 2119 Comm: kexec Not tainted 4.8.0-rc3+ #5 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011 Call Trace: dump_stack+0x4d/0x65 __warn+0xcb/0xf0 warn_slowpath_fmt+0x4f/0x60 ? find_vmap_area+0x19/0x70 ? kimage_file_post_load_cleanup+0x47/0xb0 __vunmap+0xc1/0xd0 vfree+0x2e/0x70 kimage_file_post_load_cleanup+0x5e/0xb0 SyS_kexec_file_load+0x448/0x680 ? putname+0x54/0x60 ? do_sys_open+0x190/0x1f0 entry_SYSCALL_64_fastpath+0x13/0x8f ---[ end trace 158bb74f5950ca2b ]--- Fix by setting pi->sechdrs an pi->purgatory_buf to NULL, since vfree won't try to free a NULL pointer. Link: http://lkml.kernel.org/r/1472083546-23683-1-git-send-email-bauerman@linux.vnet.ibm.com Signed-off-by: Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com> Acked-by: Baoquan He <bhe@redhat.com> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Vivek Goyal <vgoyal@redhat.com> Cc: Dave Young <dyoung@redhat.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-09-01 23:14:44 +00:00
pi->purgatory_buf = NULL;
return ret;
}
/*
* kexec_purgatory_find_symbol - find a symbol in the purgatory
* @pi: Purgatory to search in.
* @name: Name of the symbol.
*
* Return: pointer to symbol in read-only symtab on success, NULL on error.
*/
static const Elf_Sym *kexec_purgatory_find_symbol(struct purgatory_info *pi,
const char *name)
{
const Elf_Shdr *sechdrs;
const Elf_Ehdr *ehdr;
const Elf_Sym *syms;
const char *strtab;
int i, k;
if (!pi->ehdr)
return NULL;
ehdr = pi->ehdr;
sechdrs = (void *)ehdr + ehdr->e_shoff;
for (i = 0; i < ehdr->e_shnum; i++) {
if (sechdrs[i].sh_type != SHT_SYMTAB)
continue;
if (sechdrs[i].sh_link >= ehdr->e_shnum)
/* Invalid strtab section number */
continue;
strtab = (void *)ehdr + sechdrs[sechdrs[i].sh_link].sh_offset;
syms = (void *)ehdr + sechdrs[i].sh_offset;
/* Go through symbols for a match */
for (k = 0; k < sechdrs[i].sh_size/sizeof(Elf_Sym); k++) {
if (ELF_ST_BIND(syms[k].st_info) != STB_GLOBAL)
continue;
if (strcmp(strtab + syms[k].st_name, name) != 0)
continue;
if (syms[k].st_shndx == SHN_UNDEF ||
syms[k].st_shndx >= ehdr->e_shnum) {
pr_debug("Symbol: %s has bad section index %d.\n",
name, syms[k].st_shndx);
return NULL;
}
/* Found the symbol we are looking for */
return &syms[k];
}
}
return NULL;
}
void *kexec_purgatory_get_symbol_addr(struct kimage *image, const char *name)
{
struct purgatory_info *pi = &image->purgatory_info;
const Elf_Sym *sym;
Elf_Shdr *sechdr;
sym = kexec_purgatory_find_symbol(pi, name);
if (!sym)
return ERR_PTR(-EINVAL);
sechdr = &pi->sechdrs[sym->st_shndx];
/*
* Returns the address where symbol will finally be loaded after
* kexec_load_segment()
*/
return (void *)(sechdr->sh_addr + sym->st_value);
}
/*
* Get or set value of a symbol. If "get_value" is true, symbol value is
* returned in buf otherwise symbol value is set based on value in buf.
*/
int kexec_purgatory_get_set_symbol(struct kimage *image, const char *name,
void *buf, unsigned int size, bool get_value)
{
struct purgatory_info *pi = &image->purgatory_info;
const Elf_Sym *sym;
Elf_Shdr *sec;
char *sym_buf;
sym = kexec_purgatory_find_symbol(pi, name);
if (!sym)
return -EINVAL;
if (sym->st_size != size) {
pr_err("symbol %s size mismatch: expected %lu actual %u\n",
name, (unsigned long)sym->st_size, size);
return -EINVAL;
}
sec = pi->sechdrs + sym->st_shndx;
if (sec->sh_type == SHT_NOBITS) {
pr_err("symbol %s is in a bss section. Cannot %s\n", name,
get_value ? "get" : "set");
return -EINVAL;
}
sym_buf = (char *)pi->purgatory_buf + sec->sh_offset + sym->st_value;
if (get_value)
memcpy((void *)buf, sym_buf, size);
else
memcpy((void *)sym_buf, buf, size);
return 0;
}
kexec_file: make use of purgatory optional Patch series "kexec_file, x86, powerpc: refactoring for other architecutres", v2. This is a preparatory patchset for adding kexec_file support on arm64. It was originally included in a arm64 patch set[1], but Philipp is also working on their kexec_file support on s390[2] and some changes are now conflicting. So these common parts were extracted and put into a separate patch set for better integration. What's more, my original patch#4 was split into a few small chunks for easier review after Dave's comment. As such, the resulting code is basically identical with my original, and the only *visible* differences are: - renaming of _kexec_kernel_image_probe() and _kimage_file_post_load_cleanup() - change one of types of arguments at prepare_elf64_headers() Those, unfortunately, require a couple of trivial changes on the rest (#1, #6 to #13) of my arm64 kexec_file patch set[1]. Patch #1 allows making a use of purgatory optional, particularly useful for arm64. Patch #2 commonalizes arch_kexec_kernel_{image_probe, image_load, verify_sig}() and arch_kimage_file_post_load_cleanup() across architectures. Patches #3-#7 are also intended to generalize parse_elf64_headers(), along with exclude_mem_range(), to be made best re-use of. [1] http://lists.infradead.org/pipermail/linux-arm-kernel/2018-February/561182.html [2] http://lkml.iu.edu//hypermail/linux/kernel/1802.1/02596.html This patch (of 7): On arm64, crash dump kernel's usable memory is protected by *unmapping* it from kernel virtual space unlike other architectures where the region is just made read-only. It is highly unlikely that the region is accidentally corrupted and this observation rationalizes that digest check code can also be dropped from purgatory. The resulting code is so simple as it doesn't require a bit ugly re-linking/relocation stuff, i.e. arch_kexec_apply_relocations_add(). Please see: http://lists.infradead.org/pipermail/linux-arm-kernel/2017-December/545428.html All that the purgatory does is to shuffle arguments and jump into a new kernel, while we still need to have some space for a hash value (purgatory_sha256_digest) which is never checked against. As such, it doesn't make sense to have trampline code between old kernel and new kernel on arm64. This patch introduces a new configuration, ARCH_HAS_KEXEC_PURGATORY, and allows related code to be compiled in only if necessary. [takahiro.akashi@linaro.org: fix trivial screwup] Link: http://lkml.kernel.org/r/20180309093346.GF25863@linaro.org Link: http://lkml.kernel.org/r/20180306102303.9063-2-takahiro.akashi@linaro.org Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org> Acked-by: Dave Young <dyoung@redhat.com> Tested-by: Dave Young <dyoung@redhat.com> Cc: Vivek Goyal <vgoyal@redhat.com> Cc: Baoquan He <bhe@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-04-13 22:35:45 +00:00
#endif /* CONFIG_ARCH_HAS_KEXEC_PURGATORY */
int crash_exclude_mem_range(struct crash_mem *mem,
unsigned long long mstart, unsigned long long mend)
{
int i, j;
unsigned long long start, end, p_start, p_end;
struct crash_mem_range temp_range = {0, 0};
for (i = 0; i < mem->nr_ranges; i++) {
start = mem->ranges[i].start;
end = mem->ranges[i].end;
p_start = mstart;
p_end = mend;
if (mstart > end || mend < start)
continue;
/* Truncate any area outside of range */
if (mstart < start)
p_start = start;
if (mend > end)
p_end = end;
/* Found completely overlapping range */
if (p_start == start && p_end == end) {
mem->ranges[i].start = 0;
mem->ranges[i].end = 0;
if (i < mem->nr_ranges - 1) {
/* Shift rest of the ranges to left */
for (j = i; j < mem->nr_ranges - 1; j++) {
mem->ranges[j].start =
mem->ranges[j+1].start;
mem->ranges[j].end =
mem->ranges[j+1].end;
}
/*
* Continue to check if there are another overlapping ranges
* from the current position because of shifting the above
* mem ranges.
*/
i--;
mem->nr_ranges--;
continue;
}
mem->nr_ranges--;
return 0;
}
if (p_start > start && p_end < end) {
/* Split original range */
mem->ranges[i].end = p_start - 1;
temp_range.start = p_end + 1;
temp_range.end = end;
} else if (p_start != start)
mem->ranges[i].end = p_start - 1;
else
mem->ranges[i].start = p_end + 1;
break;
}
/* If a split happened, add the split to array */
if (!temp_range.end)
return 0;
/* Split happened */
if (i == mem->max_nr_ranges - 1)
return -ENOMEM;
/* Location where new range should go */
j = i + 1;
if (j < mem->nr_ranges) {
/* Move over all ranges one slot towards the end */
for (i = mem->nr_ranges - 1; i >= j; i--)
mem->ranges[i + 1] = mem->ranges[i];
}
mem->ranges[j].start = temp_range.start;
mem->ranges[j].end = temp_range.end;
mem->nr_ranges++;
return 0;
}
kexec_file: Fix kexec_file.c build error for riscv platform When CONFIG_KEXEC_FILE is set for riscv platform, the compilation of kernel/kexec_file.c generate build error: kernel/kexec_file.c: In function 'crash_prepare_elf64_headers': ./arch/riscv/include/asm/page.h:110:71: error: request for member 'virt_addr' in something not a structure or union 110 | ((x) >= PAGE_OFFSET && (!IS_ENABLED(CONFIG_64BIT) || (x) < kernel_map.virt_addr)) | ^ ./arch/riscv/include/asm/page.h:131:2: note: in expansion of macro 'is_linear_mapping' 131 | is_linear_mapping(_x) ? \ | ^~~~~~~~~~~~~~~~~ ./arch/riscv/include/asm/page.h:140:31: note: in expansion of macro '__va_to_pa_nodebug' 140 | #define __phys_addr_symbol(x) __va_to_pa_nodebug(x) | ^~~~~~~~~~~~~~~~~~ ./arch/riscv/include/asm/page.h:143:24: note: in expansion of macro '__phys_addr_symbol' 143 | #define __pa_symbol(x) __phys_addr_symbol(RELOC_HIDE((unsigned long)(x), 0)) | ^~~~~~~~~~~~~~~~~~ kernel/kexec_file.c:1327:36: note: in expansion of macro '__pa_symbol' 1327 | phdr->p_offset = phdr->p_paddr = __pa_symbol(_text); This occurs is because the "kernel_map" referenced in macro is_linear_mapping() is suppose to be the one of struct kernel_mapping defined in arch/riscv/mm/init.c, but the 2nd argument of crash_prepare_elf64_header() has same symbol name, in expansion of macro is_linear_mapping in function crash_prepare_elf64_header(), "kernel_map" actually is the local variable. Signed-off-by: Liao Chang <liaochang1@huawei.com> Link: https://lore.kernel.org/r/20220408100914.150110-2-lizhengyu3@huawei.com Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2022-04-08 10:09:09 +00:00
int crash_prepare_elf64_headers(struct crash_mem *mem, int need_kernel_map,
void **addr, unsigned long *sz)
{
Elf64_Ehdr *ehdr;
Elf64_Phdr *phdr;
unsigned long nr_cpus = num_possible_cpus(), nr_phdr, elf_sz;
unsigned char *buf;
unsigned int cpu, i;
unsigned long long notes_addr;
unsigned long mstart, mend;
kexec_file: Correctly output debugging information for the PT_LOAD ELF header Currently, when we enable the debugging switch to debug kexec_file, we always get the following incorrect results: kexec_file: Crash PT_LOAD elf header. phdr=00000000c988639b vaddr=0x0, paddr=0x0, sz=0x0 e_phnum=51 p_offset=0x0 kexec_file: Crash PT_LOAD elf header. phdr=000000003cca69a0 vaddr=0x0, paddr=0x0, sz=0x0 e_phnum=52 p_offset=0x0 kexec_file: Crash PT_LOAD elf header. phdr=00000000c584cb9f vaddr=0x0, paddr=0x0, sz=0x0 e_phnum=53 p_offset=0x0 kexec_file: Crash PT_LOAD elf header. phdr=00000000cf85d57f vaddr=0x0, paddr=0x0, sz=0x0 e_phnum=54 p_offset=0x0 kexec_file: Crash PT_LOAD elf header. phdr=00000000a4a8f847 vaddr=0x0, paddr=0x0, sz=0x0 e_phnum=55 p_offset=0x0 kexec_file: Crash PT_LOAD elf header. phdr=00000000272ec49f vaddr=0x0, paddr=0x0, sz=0x0 e_phnum=56 p_offset=0x0 kexec_file: Crash PT_LOAD elf header. phdr=00000000ea0b65de vaddr=0x0, paddr=0x0, sz=0x0 e_phnum=57 p_offset=0x0 kexec_file: Crash PT_LOAD elf header. phdr=000000001f5e490c vaddr=0x0, paddr=0x0, sz=0x0 e_phnum=58 p_offset=0x0 kexec_file: Crash PT_LOAD elf header. phdr=00000000dfe4109e vaddr=0x0, paddr=0x0, sz=0x0 e_phnum=59 p_offset=0x0 kexec_file: Crash PT_LOAD elf header. phdr=00000000480ed2b6 vaddr=0x0, paddr=0x0, sz=0x0 e_phnum=60 p_offset=0x0 kexec_file: Crash PT_LOAD elf header. phdr=0000000080b65151 vaddr=0x0, paddr=0x0, sz=0x0 e_phnum=61 p_offset=0x0 kexec_file: Crash PT_LOAD elf header. phdr=0000000024e31c5e vaddr=0x0, paddr=0x0, sz=0x0 e_phnum=62 p_offset=0x0 kexec_file: Crash PT_LOAD elf header. phdr=00000000332e0385 vaddr=0x0, paddr=0x0, sz=0x0 e_phnum=63 p_offset=0x0 kexec_file: Crash PT_LOAD elf header. phdr=000000002754d5da vaddr=0x0, paddr=0x0, sz=0x0 e_phnum=64 p_offset=0x0 kexec_file: Crash PT_LOAD elf header. phdr=00000000783320dd vaddr=0x0, paddr=0x0, sz=0x0 e_phnum=65 p_offset=0x0 kexec_file: Crash PT_LOAD elf header. phdr=0000000076fe5b64 vaddr=0x0, paddr=0x0, sz=0x0 e_phnum=66 p_offset=0x0 The reason is that kernel always prints the values of the next PT_LOAD instead of the current PT_LOAD. Change it to ensure that we can get the correct debugging information. [ mingo: Amended changelog, capitalized "ELF". ] Signed-off-by: Lianbo Jiang <lijiang@redhat.com> Signed-off-by: Ingo Molnar <mingo@kernel.org> Acked-by: Dave Young <dyoung@redhat.com> Link: https://lore.kernel.org/r/20200804044933.1973-4-lijiang@redhat.com
2020-08-04 04:49:33 +00:00
/* extra phdr for vmcoreinfo ELF note */
nr_phdr = nr_cpus + 1;
nr_phdr += mem->nr_ranges;
/*
* kexec-tools creates an extra PT_LOAD phdr for kernel text mapping
* area (for example, ffffffff80000000 - ffffffffa0000000 on x86_64).
* I think this is required by tools like gdb. So same physical
kexec_file: Correctly output debugging information for the PT_LOAD ELF header Currently, when we enable the debugging switch to debug kexec_file, we always get the following incorrect results: kexec_file: Crash PT_LOAD elf header. phdr=00000000c988639b vaddr=0x0, paddr=0x0, sz=0x0 e_phnum=51 p_offset=0x0 kexec_file: Crash PT_LOAD elf header. phdr=000000003cca69a0 vaddr=0x0, paddr=0x0, sz=0x0 e_phnum=52 p_offset=0x0 kexec_file: Crash PT_LOAD elf header. phdr=00000000c584cb9f vaddr=0x0, paddr=0x0, sz=0x0 e_phnum=53 p_offset=0x0 kexec_file: Crash PT_LOAD elf header. phdr=00000000cf85d57f vaddr=0x0, paddr=0x0, sz=0x0 e_phnum=54 p_offset=0x0 kexec_file: Crash PT_LOAD elf header. phdr=00000000a4a8f847 vaddr=0x0, paddr=0x0, sz=0x0 e_phnum=55 p_offset=0x0 kexec_file: Crash PT_LOAD elf header. phdr=00000000272ec49f vaddr=0x0, paddr=0x0, sz=0x0 e_phnum=56 p_offset=0x0 kexec_file: Crash PT_LOAD elf header. phdr=00000000ea0b65de vaddr=0x0, paddr=0x0, sz=0x0 e_phnum=57 p_offset=0x0 kexec_file: Crash PT_LOAD elf header. phdr=000000001f5e490c vaddr=0x0, paddr=0x0, sz=0x0 e_phnum=58 p_offset=0x0 kexec_file: Crash PT_LOAD elf header. phdr=00000000dfe4109e vaddr=0x0, paddr=0x0, sz=0x0 e_phnum=59 p_offset=0x0 kexec_file: Crash PT_LOAD elf header. phdr=00000000480ed2b6 vaddr=0x0, paddr=0x0, sz=0x0 e_phnum=60 p_offset=0x0 kexec_file: Crash PT_LOAD elf header. phdr=0000000080b65151 vaddr=0x0, paddr=0x0, sz=0x0 e_phnum=61 p_offset=0x0 kexec_file: Crash PT_LOAD elf header. phdr=0000000024e31c5e vaddr=0x0, paddr=0x0, sz=0x0 e_phnum=62 p_offset=0x0 kexec_file: Crash PT_LOAD elf header. phdr=00000000332e0385 vaddr=0x0, paddr=0x0, sz=0x0 e_phnum=63 p_offset=0x0 kexec_file: Crash PT_LOAD elf header. phdr=000000002754d5da vaddr=0x0, paddr=0x0, sz=0x0 e_phnum=64 p_offset=0x0 kexec_file: Crash PT_LOAD elf header. phdr=00000000783320dd vaddr=0x0, paddr=0x0, sz=0x0 e_phnum=65 p_offset=0x0 kexec_file: Crash PT_LOAD elf header. phdr=0000000076fe5b64 vaddr=0x0, paddr=0x0, sz=0x0 e_phnum=66 p_offset=0x0 The reason is that kernel always prints the values of the next PT_LOAD instead of the current PT_LOAD. Change it to ensure that we can get the correct debugging information. [ mingo: Amended changelog, capitalized "ELF". ] Signed-off-by: Lianbo Jiang <lijiang@redhat.com> Signed-off-by: Ingo Molnar <mingo@kernel.org> Acked-by: Dave Young <dyoung@redhat.com> Link: https://lore.kernel.org/r/20200804044933.1973-4-lijiang@redhat.com
2020-08-04 04:49:33 +00:00
* memory will be mapped in two ELF headers. One will contain kernel
* text virtual addresses and other will have __va(physical) addresses.
*/
nr_phdr++;
elf_sz = sizeof(Elf64_Ehdr) + nr_phdr * sizeof(Elf64_Phdr);
elf_sz = ALIGN(elf_sz, ELF_CORE_HEADER_ALIGN);
buf = vzalloc(elf_sz);
if (!buf)
return -ENOMEM;
ehdr = (Elf64_Ehdr *)buf;
phdr = (Elf64_Phdr *)(ehdr + 1);
memcpy(ehdr->e_ident, ELFMAG, SELFMAG);
ehdr->e_ident[EI_CLASS] = ELFCLASS64;
ehdr->e_ident[EI_DATA] = ELFDATA2LSB;
ehdr->e_ident[EI_VERSION] = EV_CURRENT;
ehdr->e_ident[EI_OSABI] = ELF_OSABI;
memset(ehdr->e_ident + EI_PAD, 0, EI_NIDENT - EI_PAD);
ehdr->e_type = ET_CORE;
ehdr->e_machine = ELF_ARCH;
ehdr->e_version = EV_CURRENT;
ehdr->e_phoff = sizeof(Elf64_Ehdr);
ehdr->e_ehsize = sizeof(Elf64_Ehdr);
ehdr->e_phentsize = sizeof(Elf64_Phdr);
/* Prepare one phdr of type PT_NOTE for each present CPU */
for_each_present_cpu(cpu) {
phdr->p_type = PT_NOTE;
notes_addr = per_cpu_ptr_to_phys(per_cpu_ptr(crash_notes, cpu));
phdr->p_offset = phdr->p_paddr = notes_addr;
phdr->p_filesz = phdr->p_memsz = sizeof(note_buf_t);
(ehdr->e_phnum)++;
phdr++;
}
/* Prepare one PT_NOTE header for vmcoreinfo */
phdr->p_type = PT_NOTE;
phdr->p_offset = phdr->p_paddr = paddr_vmcoreinfo_note();
phdr->p_filesz = phdr->p_memsz = VMCOREINFO_NOTE_SIZE;
(ehdr->e_phnum)++;
phdr++;
/* Prepare PT_LOAD type program header for kernel text region */
kexec_file: Fix kexec_file.c build error for riscv platform When CONFIG_KEXEC_FILE is set for riscv platform, the compilation of kernel/kexec_file.c generate build error: kernel/kexec_file.c: In function 'crash_prepare_elf64_headers': ./arch/riscv/include/asm/page.h:110:71: error: request for member 'virt_addr' in something not a structure or union 110 | ((x) >= PAGE_OFFSET && (!IS_ENABLED(CONFIG_64BIT) || (x) < kernel_map.virt_addr)) | ^ ./arch/riscv/include/asm/page.h:131:2: note: in expansion of macro 'is_linear_mapping' 131 | is_linear_mapping(_x) ? \ | ^~~~~~~~~~~~~~~~~ ./arch/riscv/include/asm/page.h:140:31: note: in expansion of macro '__va_to_pa_nodebug' 140 | #define __phys_addr_symbol(x) __va_to_pa_nodebug(x) | ^~~~~~~~~~~~~~~~~~ ./arch/riscv/include/asm/page.h:143:24: note: in expansion of macro '__phys_addr_symbol' 143 | #define __pa_symbol(x) __phys_addr_symbol(RELOC_HIDE((unsigned long)(x), 0)) | ^~~~~~~~~~~~~~~~~~ kernel/kexec_file.c:1327:36: note: in expansion of macro '__pa_symbol' 1327 | phdr->p_offset = phdr->p_paddr = __pa_symbol(_text); This occurs is because the "kernel_map" referenced in macro is_linear_mapping() is suppose to be the one of struct kernel_mapping defined in arch/riscv/mm/init.c, but the 2nd argument of crash_prepare_elf64_header() has same symbol name, in expansion of macro is_linear_mapping in function crash_prepare_elf64_header(), "kernel_map" actually is the local variable. Signed-off-by: Liao Chang <liaochang1@huawei.com> Link: https://lore.kernel.org/r/20220408100914.150110-2-lizhengyu3@huawei.com Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2022-04-08 10:09:09 +00:00
if (need_kernel_map) {
phdr->p_type = PT_LOAD;
phdr->p_flags = PF_R|PF_W|PF_X;
phdr->p_vaddr = (unsigned long) _text;
phdr->p_filesz = phdr->p_memsz = _end - _text;
phdr->p_offset = phdr->p_paddr = __pa_symbol(_text);
ehdr->e_phnum++;
phdr++;
}
/* Go through all the ranges in mem->ranges[] and prepare phdr */
for (i = 0; i < mem->nr_ranges; i++) {
mstart = mem->ranges[i].start;
mend = mem->ranges[i].end;
phdr->p_type = PT_LOAD;
phdr->p_flags = PF_R|PF_W|PF_X;
phdr->p_offset = mstart;
phdr->p_paddr = mstart;
phdr->p_vaddr = (unsigned long) __va(mstart);
phdr->p_filesz = phdr->p_memsz = mend - mstart + 1;
phdr->p_align = 0;
ehdr->e_phnum++;
kexec_file: Correctly output debugging information for the PT_LOAD ELF header Currently, when we enable the debugging switch to debug kexec_file, we always get the following incorrect results: kexec_file: Crash PT_LOAD elf header. phdr=00000000c988639b vaddr=0x0, paddr=0x0, sz=0x0 e_phnum=51 p_offset=0x0 kexec_file: Crash PT_LOAD elf header. phdr=000000003cca69a0 vaddr=0x0, paddr=0x0, sz=0x0 e_phnum=52 p_offset=0x0 kexec_file: Crash PT_LOAD elf header. phdr=00000000c584cb9f vaddr=0x0, paddr=0x0, sz=0x0 e_phnum=53 p_offset=0x0 kexec_file: Crash PT_LOAD elf header. phdr=00000000cf85d57f vaddr=0x0, paddr=0x0, sz=0x0 e_phnum=54 p_offset=0x0 kexec_file: Crash PT_LOAD elf header. phdr=00000000a4a8f847 vaddr=0x0, paddr=0x0, sz=0x0 e_phnum=55 p_offset=0x0 kexec_file: Crash PT_LOAD elf header. phdr=00000000272ec49f vaddr=0x0, paddr=0x0, sz=0x0 e_phnum=56 p_offset=0x0 kexec_file: Crash PT_LOAD elf header. phdr=00000000ea0b65de vaddr=0x0, paddr=0x0, sz=0x0 e_phnum=57 p_offset=0x0 kexec_file: Crash PT_LOAD elf header. phdr=000000001f5e490c vaddr=0x0, paddr=0x0, sz=0x0 e_phnum=58 p_offset=0x0 kexec_file: Crash PT_LOAD elf header. phdr=00000000dfe4109e vaddr=0x0, paddr=0x0, sz=0x0 e_phnum=59 p_offset=0x0 kexec_file: Crash PT_LOAD elf header. phdr=00000000480ed2b6 vaddr=0x0, paddr=0x0, sz=0x0 e_phnum=60 p_offset=0x0 kexec_file: Crash PT_LOAD elf header. phdr=0000000080b65151 vaddr=0x0, paddr=0x0, sz=0x0 e_phnum=61 p_offset=0x0 kexec_file: Crash PT_LOAD elf header. phdr=0000000024e31c5e vaddr=0x0, paddr=0x0, sz=0x0 e_phnum=62 p_offset=0x0 kexec_file: Crash PT_LOAD elf header. phdr=00000000332e0385 vaddr=0x0, paddr=0x0, sz=0x0 e_phnum=63 p_offset=0x0 kexec_file: Crash PT_LOAD elf header. phdr=000000002754d5da vaddr=0x0, paddr=0x0, sz=0x0 e_phnum=64 p_offset=0x0 kexec_file: Crash PT_LOAD elf header. phdr=00000000783320dd vaddr=0x0, paddr=0x0, sz=0x0 e_phnum=65 p_offset=0x0 kexec_file: Crash PT_LOAD elf header. phdr=0000000076fe5b64 vaddr=0x0, paddr=0x0, sz=0x0 e_phnum=66 p_offset=0x0 The reason is that kernel always prints the values of the next PT_LOAD instead of the current PT_LOAD. Change it to ensure that we can get the correct debugging information. [ mingo: Amended changelog, capitalized "ELF". ] Signed-off-by: Lianbo Jiang <lijiang@redhat.com> Signed-off-by: Ingo Molnar <mingo@kernel.org> Acked-by: Dave Young <dyoung@redhat.com> Link: https://lore.kernel.org/r/20200804044933.1973-4-lijiang@redhat.com
2020-08-04 04:49:33 +00:00
pr_debug("Crash PT_LOAD ELF header. phdr=%p vaddr=0x%llx, paddr=0x%llx, sz=0x%llx e_phnum=%d p_offset=0x%llx\n",
phdr, phdr->p_vaddr, phdr->p_paddr, phdr->p_filesz,
ehdr->e_phnum, phdr->p_offset);
kexec_file: Correctly output debugging information for the PT_LOAD ELF header Currently, when we enable the debugging switch to debug kexec_file, we always get the following incorrect results: kexec_file: Crash PT_LOAD elf header. phdr=00000000c988639b vaddr=0x0, paddr=0x0, sz=0x0 e_phnum=51 p_offset=0x0 kexec_file: Crash PT_LOAD elf header. phdr=000000003cca69a0 vaddr=0x0, paddr=0x0, sz=0x0 e_phnum=52 p_offset=0x0 kexec_file: Crash PT_LOAD elf header. phdr=00000000c584cb9f vaddr=0x0, paddr=0x0, sz=0x0 e_phnum=53 p_offset=0x0 kexec_file: Crash PT_LOAD elf header. phdr=00000000cf85d57f vaddr=0x0, paddr=0x0, sz=0x0 e_phnum=54 p_offset=0x0 kexec_file: Crash PT_LOAD elf header. phdr=00000000a4a8f847 vaddr=0x0, paddr=0x0, sz=0x0 e_phnum=55 p_offset=0x0 kexec_file: Crash PT_LOAD elf header. phdr=00000000272ec49f vaddr=0x0, paddr=0x0, sz=0x0 e_phnum=56 p_offset=0x0 kexec_file: Crash PT_LOAD elf header. phdr=00000000ea0b65de vaddr=0x0, paddr=0x0, sz=0x0 e_phnum=57 p_offset=0x0 kexec_file: Crash PT_LOAD elf header. phdr=000000001f5e490c vaddr=0x0, paddr=0x0, sz=0x0 e_phnum=58 p_offset=0x0 kexec_file: Crash PT_LOAD elf header. phdr=00000000dfe4109e vaddr=0x0, paddr=0x0, sz=0x0 e_phnum=59 p_offset=0x0 kexec_file: Crash PT_LOAD elf header. phdr=00000000480ed2b6 vaddr=0x0, paddr=0x0, sz=0x0 e_phnum=60 p_offset=0x0 kexec_file: Crash PT_LOAD elf header. phdr=0000000080b65151 vaddr=0x0, paddr=0x0, sz=0x0 e_phnum=61 p_offset=0x0 kexec_file: Crash PT_LOAD elf header. phdr=0000000024e31c5e vaddr=0x0, paddr=0x0, sz=0x0 e_phnum=62 p_offset=0x0 kexec_file: Crash PT_LOAD elf header. phdr=00000000332e0385 vaddr=0x0, paddr=0x0, sz=0x0 e_phnum=63 p_offset=0x0 kexec_file: Crash PT_LOAD elf header. phdr=000000002754d5da vaddr=0x0, paddr=0x0, sz=0x0 e_phnum=64 p_offset=0x0 kexec_file: Crash PT_LOAD elf header. phdr=00000000783320dd vaddr=0x0, paddr=0x0, sz=0x0 e_phnum=65 p_offset=0x0 kexec_file: Crash PT_LOAD elf header. phdr=0000000076fe5b64 vaddr=0x0, paddr=0x0, sz=0x0 e_phnum=66 p_offset=0x0 The reason is that kernel always prints the values of the next PT_LOAD instead of the current PT_LOAD. Change it to ensure that we can get the correct debugging information. [ mingo: Amended changelog, capitalized "ELF". ] Signed-off-by: Lianbo Jiang <lijiang@redhat.com> Signed-off-by: Ingo Molnar <mingo@kernel.org> Acked-by: Dave Young <dyoung@redhat.com> Link: https://lore.kernel.org/r/20200804044933.1973-4-lijiang@redhat.com
2020-08-04 04:49:33 +00:00
phdr++;
}
*addr = buf;
*sz = elf_sz;
return 0;
}