Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]
Groups > linux.kernel > #1718948 > unrolled thread
| Started by | AKASHI Takahiro <takahiro.akashi@linaro.org> |
|---|---|
| First post | 2017-08-24 10:20 +0200 |
| Last post | 2017-08-24 10:30 +0200 |
| Articles | 9 on this page of 49 — 8 participants |
Back to article view | Back to linux.kernel
[PATCH 00/14] arm64: kexec: add kexec_file_load support AKASHI Takahiro <takahiro.akashi@linaro.org> - 2017-08-24 10:20 +0200
[PATCH 14/14] arm64: kexec_file: add vmlinux format support AKASHI Takahiro <takahiro.akashi@linaro.org> - 2017-08-24 10:20 +0200
Re: [PATCH 14/14] arm64: kexec_file: add vmlinux format support Mark Rutland <mark.rutland@arm.com> - 2017-08-24 19:40 +0200
Re: [PATCH 14/14] arm64: kexec_file: add vmlinux format support AKASHI Takahiro <takahiro.akashi@linaro.org> - 2017-08-25 04:10 +0200
Re: [PATCH 14/14] arm64: kexec_file: add vmlinux format support Dave Young <dyoung@redhat.com> - 2017-08-25 08:20 +0200
Re: [PATCH 14/14] arm64: kexec_file: add vmlinux format support AKASHI Takahiro <takahiro.akashi@linaro.org> - 2017-09-08 05:00 +0200
Re: [PATCH 14/14] arm64: kexec_file: add vmlinux format support Mark Rutland <mark.rutland@arm.com> - 2017-08-29 12:10 +0200
Re: [PATCH 14/14] arm64: kexec_file: add vmlinux format support Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com> - 2017-08-29 18:20 +0200
Re: [PATCH 14/14] arm64: kexec_file: add vmlinux format support Michael Ellerman <mpe@ellerman.id.au> - 2017-08-30 10:50 +0200
Re: [PATCH 14/14] arm64: kexec_file: add vmlinux format support AKASHI Takahiro <takahiro.akashi@linaro.org> - 2017-09-08 05:10 +0200
[PATCH 08/14] arm64: kexec_file: create purgatory AKASHI Takahiro <takahiro.akashi@linaro.org> - 2017-08-24 10:20 +0200
Re: [PATCH 08/14] arm64: kexec_file: create purgatory Ard Biesheuvel <ard.biesheuvel@linaro.org> - 2017-08-24 11:20 +0200
Re: [PATCH 08/14] arm64: kexec_file: create purgatory AKASHI Takahiro <takahiro.akashi@linaro.org> - 2017-08-25 03:20 +0200
Re: [PATCH 08/14] arm64: kexec_file: create purgatory Mark Rutland <mark.rutland@arm.com> - 2017-08-24 19:00 +0200
Re: [PATCH 08/14] arm64: kexec_file: create purgatory AKASHI Takahiro <takahiro.akashi@linaro.org> - 2017-08-25 03:10 +0200
Re: [PATCH 08/14] arm64: kexec_file: create purgatory Mark Rutland <mark.rutland@arm.com> - 2017-08-25 12:30 +0200
Re: [PATCH 08/14] arm64: kexec_file: create purgatory Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com> - 2017-08-25 18:20 +0200
Re: [PATCH 08/14] arm64: kexec_file: create purgatory AKASHI Takahiro <takahiro.akashi@linaro.org> - 2017-09-08 04:50 +0200
[PATCH 02/14] include: pe.h: remove message[] from mz header definition AKASHI Takahiro <takahiro.akashi@linaro.org> - 2017-08-24 10:20 +0200
Re: [PATCH 02/14] include: pe.h: remove message[] from mz header definition Ard Biesheuvel <ard.biesheuvel@linaro.org> - 2017-08-24 11:10 +0200
[PATCH 01/14] MODSIGN: Export module signature definitions AKASHI Takahiro <takahiro.akashi@linaro.org> - 2017-08-24 10:20 +0200
[PATCH 09/14] arm64: kexec_file: add sha256 digest check in purgatory AKASHI Takahiro <takahiro.akashi@linaro.org> - 2017-08-24 10:30 +0200
Re: [PATCH 09/14] arm64: kexec_file: add sha256 digest check in purgatory Ard Biesheuvel <ard.biesheuvel@linaro.org> - 2017-08-24 11:20 +0200
Re: [PATCH 09/14] arm64: kexec_file: add sha256 digest check in purgatory AKASHI Takahiro <takahiro.akashi@linaro.org> - 2017-08-25 03:30 +0200
Re: [PATCH 09/14] arm64: kexec_file: add sha256 digest check in purgatory Mark Rutland <mark.rutland@arm.com> - 2017-08-24 19:10 +0200
Re: [PATCH 09/14] arm64: kexec_file: add sha256 digest check in purgatory AKASHI Takahiro <takahiro.akashi@linaro.org> - 2017-08-25 03:30 +0200
Re: [PATCH 09/14] arm64: kexec_file: add sha256 digest check in purgatory Mark Rutland <mark.rutland@arm.com> - 2017-08-25 12:50 +0200
Re: [PATCH 09/14] arm64: kexec_file: add sha256 digest check in purgatory AKASHI Takahiro <takahiro.akashi@linaro.org> - 2017-09-08 04:50 +0200
Re: [PATCH 09/14] arm64: kexec_file: add sha256 digest check in purgatory Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com> - 2017-09-08 18:00 +0200
[PATCH 07/14] asm-generic: add kexec_file_load system call to unistd.h AKASHI Takahiro <takahiro.akashi@linaro.org> - 2017-08-24 10:30 +0200
Re: [PATCH 07/14] asm-generic: add kexec_file_load system call to unistd.h Arnd Bergmann <arnd@arndb.de> - 2017-08-24 13:00 +0200
[PATCH 13/14] arm64: kexec_file: add Image format support AKASHI Takahiro <takahiro.akashi@linaro.org> - 2017-08-24 10:30 +0200
Re: [PATCH 13/14] arm64: kexec_file: add Image format support Mark Rutland <mark.rutland@arm.com> - 2017-08-24 19:30 +0200
Re: [PATCH 13/14] arm64: kexec_file: add Image format support AKASHI Takahiro <takahiro.akashi@linaro.org> - 2017-08-25 04:00 +0200
[PATCH 03/14] resource: add walk_system_ram_res_rev() AKASHI Takahiro <takahiro.akashi@linaro.org> - 2017-08-24 10:30 +0200
Re: [PATCH 03/14] resource: add walk_system_ram_res_rev() Ard Biesheuvel <ard.biesheuvel@linaro.org> - 2017-08-24 11:10 +0200
Re: [PATCH 03/14] resource: add walk_system_ram_res_rev() AKASHI Takahiro <takahiro.akashi@linaro.org> - 2017-08-25 03:00 +0200
Re: [PATCH 03/14] resource: add walk_system_ram_res_rev() Pratyush Anand <panand@redhat.com> - 2017-08-31 04:40 +0200
Re: [PATCH 03/14] resource: add walk_system_ram_res_rev() AKASHI Takahiro <takahiro.akashi@linaro.org> - 2017-09-08 04:40 +0200
[PATCH 10/14] arm64: kexec_file: load initrd, device-tree and purgatory segments AKASHI Takahiro <takahiro.akashi@linaro.org> - 2017-08-24 10:30 +0200
Re: [PATCH 10/14] arm64: kexec_file: load initrd, device-tree and purgatory segments Mark Rutland <mark.rutland@arm.com> - 2017-08-24 19:20 +0200
Re: [PATCH 10/14] arm64: kexec_file: load initrd, device-tree and purgatory segments AKASHI Takahiro <takahiro.akashi@linaro.org> - 2017-08-25 03:40 +0200
[PATCH 04/14] kexec_file: factor out vmlinux (elf) parser from powerpc AKASHI Takahiro <takahiro.akashi@linaro.org> - 2017-08-24 10:30 +0200
[PATCH 05/14] kexec_file: factor out crashdump elf header function from x86 AKASHI Takahiro <takahiro.akashi@linaro.org> - 2017-08-24 10:30 +0200
Re: [PATCH 05/14] kexec_file: factor out crashdump elf header function from x86 Dave Young <dyoung@redhat.com> - 2017-08-25 07:50 +0200
Re: [PATCH 05/14] kexec_file: factor out crashdump elf header function from x86 AKASHI Takahiro <takahiro.akashi@linaro.org> - 2017-09-08 04:30 +0200
[PATCH 06/14] kexec_file: add kexec_add_segment() AKASHI Takahiro <takahiro.akashi@linaro.org> - 2017-08-24 10:30 +0200
[PATCH 12/14] arm64: enable KEXEC_FILE config AKASHI Takahiro <takahiro.akashi@linaro.org> - 2017-08-24 10:30 +0200
[PATCH 11/14] arm64: kexec_file: set up for crash dump adding elf core header AKASHI Takahiro <takahiro.akashi@linaro.org> - 2017-08-24 10:30 +0200
Page 3 of 3 — ← Prev page 1 2 [3]
| From | Mark Rutland <mark.rutland@arm.com> |
|---|---|
| Date | 2017-08-24 19:20 +0200 |
| Subject | Re: [PATCH 10/14] arm64: kexec_file: load initrd, device-tree and purgatory segments |
| Message-ID | <ui3Xr-Z6-3@gated-at.bofh.it> |
| In reply to | #1718969 |
On Thu, Aug 24, 2017 at 05:18:07PM +0900, AKASHI Takahiro wrote:
> load_other_segments() sets up and adds all the memory segments necessary
> other than kernel, including initrd, device-tree blob and purgatory.
> Most of the code was borrowed from kexec-tools' counterpart.
>
> In addition, arch_kexec_image_probe(), arch_kexec_image_load() and
> arch_kexec_kernel_verify_sig() are stubs for supporting multiple types
> of kernel image formats.
>
> Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org>
> Cc: Catalin Marinas <catalin.marinas@arm.com>
> Cc: Will Deacon <will.deacon@arm.com>
> ---
> arch/arm64/include/asm/kexec.h | 18 +++
> arch/arm64/kernel/machine_kexec_file.c | 255 +++++++++++++++++++++++++++++++++
> 2 files changed, 273 insertions(+)
> +int load_other_segments(struct kimage *image, unsigned long kernel_load_addr,
> + char *initrd, unsigned long initrd_len,
> + char *cmdline, unsigned long cmdline_len)
> +{
> + struct kexec_buf kbuf;
> + unsigned long initrd_load_addr = 0;
> + unsigned long purgatory_load_addr, dtb_load_addr;
> + char *dtb = NULL;
> + unsigned long dtb_len;
> + int ret = 0;
> +
> + kbuf.image = image;
> +
> + /* Load initrd */
> + if (initrd) {
> + kbuf.buffer = initrd;
> + kbuf.bufsz = initrd_len;
> + kbuf.memsz = initrd_len;
> + kbuf.buf_align = PAGE_SIZE;
> + /* within 1GB-aligned window of up to 32GB in size */
> + kbuf.buf_min = kernel_load_addr;
> + kbuf.buf_max = round_down(kernel_load_addr, SZ_1G)
> + + (unsigned long)SZ_1G * 31;
> + kbuf.top_down = 0;
> +
> + ret = kexec_add_buffer(&kbuf);
> + if (ret)
> + goto out_err;
> + initrd_load_addr = kbuf.mem;
> +
> + pr_debug("Loaded initrd at 0x%lx bufsz=0x%lx memsz=0x%lx\n",
> + initrd_load_addr, initrd_len, initrd_len);
> + }
> +
> + /* Load dtb blob */
> + ret = setup_dtb(image, initrd_load_addr, initrd_len,
> + cmdline, cmdline_len, &dtb, &dtb_len);
> + if (ret) {
> + pr_err("Preparing for new dtb failed\n");
> + goto out_err;
> + }
> +
> + kbuf.buffer = dtb;
> + kbuf.bufsz = dtb_len;
> + kbuf.memsz = dtb_len;
> + /* not across 2MB boundary */
> + kbuf.buf_align = SZ_2M;
> + /*
> + * Note for backporting:
> + * On kernel prior to v4.2, fdt must reside within 512MB block
> + * where the kernel also resides. So
> + * kbuf.buf_min = round_down(kernel_load_addr, SZ_512M);
> + * kbuf.buf_max = round_up(kernel_load_addr, SZ_512M);
> + * would be required.
> + */
> + kbuf.buf_min = kernel_load_addr;
> + kbuf.buf_max = ULONG_MAX;
> + kbuf.top_down = 1;
IIUC, this is trying to load the DTB above the kernel. Is that correct?
Assuming so, shouldn't that kernel_load_addr be kernel_load_addr +
image_size from the kernel header?
Otherwise, if the kernel is loaded close to the end of memory, the DTB
could overlap.
Thanks,
Mark.
[toc] | [prev] | [next] | [standalone]
| From | AKASHI Takahiro <takahiro.akashi@linaro.org> |
|---|---|
| Date | 2017-08-25 03:40 +0200 |
| Subject | Re: [PATCH 10/14] arm64: kexec_file: load initrd, device-tree and purgatory segments |
| Message-ID | <uibLk-5Xx-9@gated-at.bofh.it> |
| In reply to | #1719449 |
On Thu, Aug 24, 2017 at 06:11:31PM +0100, Mark Rutland wrote:
> On Thu, Aug 24, 2017 at 05:18:07PM +0900, AKASHI Takahiro wrote:
> > load_other_segments() sets up and adds all the memory segments necessary
> > other than kernel, including initrd, device-tree blob and purgatory.
> > Most of the code was borrowed from kexec-tools' counterpart.
> >
> > In addition, arch_kexec_image_probe(), arch_kexec_image_load() and
> > arch_kexec_kernel_verify_sig() are stubs for supporting multiple types
> > of kernel image formats.
> >
> > Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org>
> > Cc: Catalin Marinas <catalin.marinas@arm.com>
> > Cc: Will Deacon <will.deacon@arm.com>
> > ---
> > arch/arm64/include/asm/kexec.h | 18 +++
> > arch/arm64/kernel/machine_kexec_file.c | 255 +++++++++++++++++++++++++++++++++
> > 2 files changed, 273 insertions(+)
>
> > +int load_other_segments(struct kimage *image, unsigned long kernel_load_addr,
> > + char *initrd, unsigned long initrd_len,
> > + char *cmdline, unsigned long cmdline_len)
> > +{
> > + struct kexec_buf kbuf;
> > + unsigned long initrd_load_addr = 0;
> > + unsigned long purgatory_load_addr, dtb_load_addr;
> > + char *dtb = NULL;
> > + unsigned long dtb_len;
> > + int ret = 0;
> > +
> > + kbuf.image = image;
> > +
> > + /* Load initrd */
> > + if (initrd) {
> > + kbuf.buffer = initrd;
> > + kbuf.bufsz = initrd_len;
> > + kbuf.memsz = initrd_len;
> > + kbuf.buf_align = PAGE_SIZE;
> > + /* within 1GB-aligned window of up to 32GB in size */
> > + kbuf.buf_min = kernel_load_addr;
> > + kbuf.buf_max = round_down(kernel_load_addr, SZ_1G)
> > + + (unsigned long)SZ_1G * 31;
> > + kbuf.top_down = 0;
> > +
> > + ret = kexec_add_buffer(&kbuf);
> > + if (ret)
> > + goto out_err;
> > + initrd_load_addr = kbuf.mem;
> > +
> > + pr_debug("Loaded initrd at 0x%lx bufsz=0x%lx memsz=0x%lx\n",
> > + initrd_load_addr, initrd_len, initrd_len);
> > + }
> > +
> > + /* Load dtb blob */
> > + ret = setup_dtb(image, initrd_load_addr, initrd_len,
> > + cmdline, cmdline_len, &dtb, &dtb_len);
> > + if (ret) {
> > + pr_err("Preparing for new dtb failed\n");
> > + goto out_err;
> > + }
> > +
> > + kbuf.buffer = dtb;
> > + kbuf.bufsz = dtb_len;
> > + kbuf.memsz = dtb_len;
> > + /* not across 2MB boundary */
> > + kbuf.buf_align = SZ_2M;
> > + /*
> > + * Note for backporting:
> > + * On kernel prior to v4.2, fdt must reside within 512MB block
> > + * where the kernel also resides. So
> > + * kbuf.buf_min = round_down(kernel_load_addr, SZ_512M);
> > + * kbuf.buf_max = round_up(kernel_load_addr, SZ_512M);
> > + * would be required.
> > + */
> > + kbuf.buf_min = kernel_load_addr;
> > + kbuf.buf_max = ULONG_MAX;
> > + kbuf.top_down = 1;
>
> IIUC, this is trying to load the DTB above the kernel. Is that correct?
Yes.
> Assuming so, shouldn't that kernel_load_addr be kernel_load_addr +
> image_size from the kernel header?
Okey, it would be much safer.
> Otherwise, if the kernel is loaded close to the end of memory, the DTB
> could overlap.
Right, but we allocate the kernel from "bottom up"(top_down=0)
and such a corruption is very unlikely. If it happens, it means
that system memory is just too small.
Thanks,
-Takahiro AKASHI
> Thanks,
> Mark.
[toc] | [prev] | [next] | [standalone]
| From | AKASHI Takahiro <takahiro.akashi@linaro.org> |
|---|---|
| Date | 2017-08-24 10:30 +0200 |
| Subject | [PATCH 04/14] kexec_file: factor out vmlinux (elf) parser from powerpc |
| Message-ID | <uhVGy-405-25@gated-at.bofh.it> |
| In reply to | #1718948 |
build_elf_exec_info() can also be useful for other architectures,
including arm64. So let it factored out.
Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: Baoquan He <bhe@redhat.com>
---
arch/Kconfig | 3 +
arch/powerpc/Kconfig | 1 +
arch/powerpc/kernel/kexec_elf_64.c | 464 -------------------------------------
include/linux/elf.h | 62 +++++
include/linux/kexec.h | 19 ++
kernel/Makefile | 1 +
kernel/kexec_file_elf.c | 454 ++++++++++++++++++++++++++++++++++++
7 files changed, 540 insertions(+), 464 deletions(-)
create mode 100644 kernel/kexec_file_elf.c
diff --git a/arch/Kconfig b/arch/Kconfig
index 21d0089117fe..e940d16412f4 100644
--- a/arch/Kconfig
+++ b/arch/Kconfig
@@ -9,6 +9,9 @@ config KEXEC_CORE
select CRASH_CORE
bool
+config KEXEC_FILE_ELF
+ bool
+
config HAVE_IMA_KEXEC
bool
diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig
index 36f858c37ca7..f73921bbe29a 100644
--- a/arch/powerpc/Kconfig
+++ b/arch/powerpc/Kconfig
@@ -529,6 +529,7 @@ config KEXEC
config KEXEC_FILE
bool "kexec file based system call"
select KEXEC_CORE
+ select KEXEC_FILE_ELF
select HAVE_IMA_KEXEC
select BUILD_BIN2C
depends on PPC64
diff --git a/arch/powerpc/kernel/kexec_elf_64.c b/arch/powerpc/kernel/kexec_elf_64.c
index 9a42309b091a..a0c92bd14259 100644
--- a/arch/powerpc/kernel/kexec_elf_64.c
+++ b/arch/powerpc/kernel/kexec_elf_64.c
@@ -26,475 +26,11 @@
#include <linux/elf.h>
#include <linux/kexec.h>
#include <linux/libfdt.h>
-#include <linux/module.h>
#include <linux/of_fdt.h>
#include <linux/slab.h>
-#include <linux/types.h>
#define PURGATORY_STACK_SIZE (16 * 1024)
-#define elf_addr_to_cpu elf64_to_cpu
-
-#ifndef Elf_Rel
-#define Elf_Rel Elf64_Rel
-#endif /* Elf_Rel */
-
-struct elf_info {
- /*
- * Where the ELF binary contents are kept.
- * Memory managed by the user of the struct.
- */
- const char *buffer;
-
- const struct elfhdr *ehdr;
- const struct elf_phdr *proghdrs;
- struct elf_shdr *sechdrs;
-};
-
-static inline bool elf_is_elf_file(const struct elfhdr *ehdr)
-{
- return memcmp(ehdr->e_ident, ELFMAG, SELFMAG) == 0;
-}
-
-static uint64_t elf64_to_cpu(const struct elfhdr *ehdr, uint64_t value)
-{
- if (ehdr->e_ident[EI_DATA] == ELFDATA2LSB)
- value = le64_to_cpu(value);
- else if (ehdr->e_ident[EI_DATA] == ELFDATA2MSB)
- value = be64_to_cpu(value);
-
- return value;
-}
-
-static uint16_t elf16_to_cpu(const struct elfhdr *ehdr, uint16_t value)
-{
- if (ehdr->e_ident[EI_DATA] == ELFDATA2LSB)
- value = le16_to_cpu(value);
- else if (ehdr->e_ident[EI_DATA] == ELFDATA2MSB)
- value = be16_to_cpu(value);
-
- return value;
-}
-
-static uint32_t elf32_to_cpu(const struct elfhdr *ehdr, uint32_t value)
-{
- if (ehdr->e_ident[EI_DATA] == ELFDATA2LSB)
- value = le32_to_cpu(value);
- else if (ehdr->e_ident[EI_DATA] == ELFDATA2MSB)
- value = be32_to_cpu(value);
-
- return value;
-}
-
-/**
- * elf_is_ehdr_sane - check that it is safe to use the ELF header
- * @buf_len: size of the buffer in which the ELF file is loaded.
- */
-static bool elf_is_ehdr_sane(const struct elfhdr *ehdr, size_t buf_len)
-{
- if (ehdr->e_phnum > 0 && ehdr->e_phentsize != sizeof(struct elf_phdr)) {
- pr_debug("Bad program header size.\n");
- return false;
- } else if (ehdr->e_shnum > 0 &&
- ehdr->e_shentsize != sizeof(struct elf_shdr)) {
- pr_debug("Bad section header size.\n");
- return false;
- } else if (ehdr->e_ident[EI_VERSION] != EV_CURRENT ||
- ehdr->e_version != EV_CURRENT) {
- pr_debug("Unknown ELF version.\n");
- return false;
- }
-
- if (ehdr->e_phoff > 0 && ehdr->e_phnum > 0) {
- size_t phdr_size;
-
- /*
- * e_phnum is at most 65535 so calculating the size of the
- * program header cannot overflow.
- */
- phdr_size = sizeof(struct elf_phdr) * ehdr->e_phnum;
-
- /* Sanity check the program header table location. */
- if (ehdr->e_phoff + phdr_size < ehdr->e_phoff) {
- pr_debug("Program headers at invalid location.\n");
- return false;
- } else if (ehdr->e_phoff + phdr_size > buf_len) {
- pr_debug("Program headers truncated.\n");
- return false;
- }
- }
-
- if (ehdr->e_shoff > 0 && ehdr->e_shnum > 0) {
- size_t shdr_size;
-
- /*
- * e_shnum is at most 65536 so calculating
- * the size of the section header cannot overflow.
- */
- shdr_size = sizeof(struct elf_shdr) * ehdr->e_shnum;
-
- /* Sanity check the section header table location. */
- if (ehdr->e_shoff + shdr_size < ehdr->e_shoff) {
- pr_debug("Section headers at invalid location.\n");
- return false;
- } else if (ehdr->e_shoff + shdr_size > buf_len) {
- pr_debug("Section headers truncated.\n");
- return false;
- }
- }
-
- return true;
-}
-
-static int elf_read_ehdr(const char *buf, size_t len, struct elfhdr *ehdr)
-{
- struct elfhdr *buf_ehdr;
-
- if (len < sizeof(*buf_ehdr)) {
- pr_debug("Buffer is too small to hold ELF header.\n");
- return -ENOEXEC;
- }
-
- memset(ehdr, 0, sizeof(*ehdr));
- memcpy(ehdr->e_ident, buf, sizeof(ehdr->e_ident));
- if (!elf_is_elf_file(ehdr)) {
- pr_debug("No ELF header magic.\n");
- return -ENOEXEC;
- }
-
- if (ehdr->e_ident[EI_CLASS] != ELF_CLASS) {
- pr_debug("Not a supported ELF class.\n");
- return -ENOEXEC;
- } else if (ehdr->e_ident[EI_DATA] != ELFDATA2LSB &&
- ehdr->e_ident[EI_DATA] != ELFDATA2MSB) {
- pr_debug("Not a supported ELF data format.\n");
- return -ENOEXEC;
- }
-
- buf_ehdr = (struct elfhdr *) buf;
- if (elf16_to_cpu(ehdr, buf_ehdr->e_ehsize) != sizeof(*buf_ehdr)) {
- pr_debug("Bad ELF header size.\n");
- return -ENOEXEC;
- }
-
- ehdr->e_type = elf16_to_cpu(ehdr, buf_ehdr->e_type);
- ehdr->e_machine = elf16_to_cpu(ehdr, buf_ehdr->e_machine);
- ehdr->e_version = elf32_to_cpu(ehdr, buf_ehdr->e_version);
- ehdr->e_entry = elf_addr_to_cpu(ehdr, buf_ehdr->e_entry);
- ehdr->e_phoff = elf_addr_to_cpu(ehdr, buf_ehdr->e_phoff);
- ehdr->e_shoff = elf_addr_to_cpu(ehdr, buf_ehdr->e_shoff);
- ehdr->e_flags = elf32_to_cpu(ehdr, buf_ehdr->e_flags);
- ehdr->e_phentsize = elf16_to_cpu(ehdr, buf_ehdr->e_phentsize);
- ehdr->e_phnum = elf16_to_cpu(ehdr, buf_ehdr->e_phnum);
- ehdr->e_shentsize = elf16_to_cpu(ehdr, buf_ehdr->e_shentsize);
- ehdr->e_shnum = elf16_to_cpu(ehdr, buf_ehdr->e_shnum);
- ehdr->e_shstrndx = elf16_to_cpu(ehdr, buf_ehdr->e_shstrndx);
-
- return elf_is_ehdr_sane(ehdr, len) ? 0 : -ENOEXEC;
-}
-
-/**
- * elf_is_phdr_sane - check that it is safe to use the program header
- * @buf_len: size of the buffer in which the ELF file is loaded.
- */
-static bool elf_is_phdr_sane(const struct elf_phdr *phdr, size_t buf_len)
-{
-
- if (phdr->p_offset + phdr->p_filesz < phdr->p_offset) {
- pr_debug("ELF segment location wraps around.\n");
- return false;
- } else if (phdr->p_offset + phdr->p_filesz > buf_len) {
- pr_debug("ELF segment not in file.\n");
- return false;
- } else if (phdr->p_paddr + phdr->p_memsz < phdr->p_paddr) {
- pr_debug("ELF segment address wraps around.\n");
- return false;
- }
-
- return true;
-}
-
-static int elf_read_phdr(const char *buf, size_t len, struct elf_info *elf_info,
- int idx)
-{
- /* Override the const in proghdrs, we are the ones doing the loading. */
- struct elf_phdr *phdr = (struct elf_phdr *) &elf_info->proghdrs[idx];
- const char *pbuf;
- struct elf_phdr *buf_phdr;
-
- pbuf = buf + elf_info->ehdr->e_phoff + (idx * sizeof(*buf_phdr));
- buf_phdr = (struct elf_phdr *) pbuf;
-
- phdr->p_type = elf32_to_cpu(elf_info->ehdr, buf_phdr->p_type);
- phdr->p_offset = elf_addr_to_cpu(elf_info->ehdr, buf_phdr->p_offset);
- phdr->p_paddr = elf_addr_to_cpu(elf_info->ehdr, buf_phdr->p_paddr);
- phdr->p_vaddr = elf_addr_to_cpu(elf_info->ehdr, buf_phdr->p_vaddr);
- phdr->p_flags = elf32_to_cpu(elf_info->ehdr, buf_phdr->p_flags);
-
- /*
- * The following fields have a type equivalent to Elf_Addr
- * both in 32 bit and 64 bit ELF.
- */
- phdr->p_filesz = elf_addr_to_cpu(elf_info->ehdr, buf_phdr->p_filesz);
- phdr->p_memsz = elf_addr_to_cpu(elf_info->ehdr, buf_phdr->p_memsz);
- phdr->p_align = elf_addr_to_cpu(elf_info->ehdr, buf_phdr->p_align);
-
- return elf_is_phdr_sane(phdr, len) ? 0 : -ENOEXEC;
-}
-
-/**
- * elf_read_phdrs - read the program headers from the buffer
- *
- * This function assumes that the program header table was checked for sanity.
- * Use elf_is_ehdr_sane() if it wasn't.
- */
-static int elf_read_phdrs(const char *buf, size_t len,
- struct elf_info *elf_info)
-{
- size_t phdr_size, i;
- const struct elfhdr *ehdr = elf_info->ehdr;
-
- /*
- * e_phnum is at most 65535 so calculating the size of the
- * program header cannot overflow.
- */
- phdr_size = sizeof(struct elf_phdr) * ehdr->e_phnum;
-
- elf_info->proghdrs = kzalloc(phdr_size, GFP_KERNEL);
- if (!elf_info->proghdrs)
- return -ENOMEM;
-
- for (i = 0; i < ehdr->e_phnum; i++) {
- int ret;
-
- ret = elf_read_phdr(buf, len, elf_info, i);
- if (ret) {
- kfree(elf_info->proghdrs);
- elf_info->proghdrs = NULL;
- return ret;
- }
- }
-
- return 0;
-}
-
-/**
- * elf_is_shdr_sane - check that it is safe to use the section header
- * @buf_len: size of the buffer in which the ELF file is loaded.
- */
-static bool elf_is_shdr_sane(const struct elf_shdr *shdr, size_t buf_len)
-{
- bool size_ok;
-
- /* SHT_NULL headers have undefined values, so we can't check them. */
- if (shdr->sh_type == SHT_NULL)
- return true;
-
- /* Now verify sh_entsize */
- switch (shdr->sh_type) {
- case SHT_SYMTAB:
- size_ok = shdr->sh_entsize == sizeof(Elf_Sym);
- break;
- case SHT_RELA:
- size_ok = shdr->sh_entsize == sizeof(Elf_Rela);
- break;
- case SHT_DYNAMIC:
- size_ok = shdr->sh_entsize == sizeof(Elf_Dyn);
- break;
- case SHT_REL:
- size_ok = shdr->sh_entsize == sizeof(Elf_Rel);
- break;
- case SHT_NOTE:
- case SHT_PROGBITS:
- case SHT_HASH:
- case SHT_NOBITS:
- default:
- /*
- * This is a section whose entsize requirements
- * I don't care about. If I don't know about
- * the section I can't care about it's entsize
- * requirements.
- */
- size_ok = true;
- break;
- }
-
- if (!size_ok) {
- pr_debug("ELF section with wrong entry size.\n");
- return false;
- } else if (shdr->sh_addr + shdr->sh_size < shdr->sh_addr) {
- pr_debug("ELF section address wraps around.\n");
- return false;
- }
-
- if (shdr->sh_type != SHT_NOBITS) {
- if (shdr->sh_offset + shdr->sh_size < shdr->sh_offset) {
- pr_debug("ELF section location wraps around.\n");
- return false;
- } else if (shdr->sh_offset + shdr->sh_size > buf_len) {
- pr_debug("ELF section not in file.\n");
- return false;
- }
- }
-
- return true;
-}
-
-static int elf_read_shdr(const char *buf, size_t len, struct elf_info *elf_info,
- int idx)
-{
- struct elf_shdr *shdr = &elf_info->sechdrs[idx];
- const struct elfhdr *ehdr = elf_info->ehdr;
- const char *sbuf;
- struct elf_shdr *buf_shdr;
-
- sbuf = buf + ehdr->e_shoff + idx * sizeof(*buf_shdr);
- buf_shdr = (struct elf_shdr *) sbuf;
-
- shdr->sh_name = elf32_to_cpu(ehdr, buf_shdr->sh_name);
- shdr->sh_type = elf32_to_cpu(ehdr, buf_shdr->sh_type);
- shdr->sh_addr = elf_addr_to_cpu(ehdr, buf_shdr->sh_addr);
- shdr->sh_offset = elf_addr_to_cpu(ehdr, buf_shdr->sh_offset);
- shdr->sh_link = elf32_to_cpu(ehdr, buf_shdr->sh_link);
- shdr->sh_info = elf32_to_cpu(ehdr, buf_shdr->sh_info);
-
- /*
- * The following fields have a type equivalent to Elf_Addr
- * both in 32 bit and 64 bit ELF.
- */
- shdr->sh_flags = elf_addr_to_cpu(ehdr, buf_shdr->sh_flags);
- shdr->sh_size = elf_addr_to_cpu(ehdr, buf_shdr->sh_size);
- shdr->sh_addralign = elf_addr_to_cpu(ehdr, buf_shdr->sh_addralign);
- shdr->sh_entsize = elf_addr_to_cpu(ehdr, buf_shdr->sh_entsize);
-
- return elf_is_shdr_sane(shdr, len) ? 0 : -ENOEXEC;
-}
-
-/**
- * elf_read_shdrs - read the section headers from the buffer
- *
- * This function assumes that the section header table was checked for sanity.
- * Use elf_is_ehdr_sane() if it wasn't.
- */
-static int elf_read_shdrs(const char *buf, size_t len,
- struct elf_info *elf_info)
-{
- size_t shdr_size, i;
-
- /*
- * e_shnum is at most 65536 so calculating
- * the size of the section header cannot overflow.
- */
- shdr_size = sizeof(struct elf_shdr) * elf_info->ehdr->e_shnum;
-
- elf_info->sechdrs = kzalloc(shdr_size, GFP_KERNEL);
- if (!elf_info->sechdrs)
- return -ENOMEM;
-
- for (i = 0; i < elf_info->ehdr->e_shnum; i++) {
- int ret;
-
- ret = elf_read_shdr(buf, len, elf_info, i);
- if (ret) {
- kfree(elf_info->sechdrs);
- elf_info->sechdrs = NULL;
- return ret;
- }
- }
-
- return 0;
-}
-
-/**
- * elf_read_from_buffer - read ELF file and sets up ELF header and ELF info
- * @buf: Buffer to read ELF file from.
- * @len: Size of @buf.
- * @ehdr: Pointer to existing struct which will be populated.
- * @elf_info: Pointer to existing struct which will be populated.
- *
- * This function allows reading ELF files with different byte order than
- * the kernel, byte-swapping the fields as needed.
- *
- * Return:
- * On success returns 0, and the caller should call elf_free_info(elf_info) to
- * free the memory allocated for the section and program headers.
- */
-int elf_read_from_buffer(const char *buf, size_t len, struct elfhdr *ehdr,
- struct elf_info *elf_info)
-{
- int ret;
-
- ret = elf_read_ehdr(buf, len, ehdr);
- if (ret)
- return ret;
-
- elf_info->buffer = buf;
- elf_info->ehdr = ehdr;
- if (ehdr->e_phoff > 0 && ehdr->e_phnum > 0) {
- ret = elf_read_phdrs(buf, len, elf_info);
- if (ret)
- return ret;
- }
- if (ehdr->e_shoff > 0 && ehdr->e_shnum > 0) {
- ret = elf_read_shdrs(buf, len, elf_info);
- if (ret) {
- kfree(elf_info->proghdrs);
- return ret;
- }
- }
-
- return 0;
-}
-
-/**
- * elf_free_info - free memory allocated by elf_read_from_buffer
- */
-void elf_free_info(struct elf_info *elf_info)
-{
- kfree(elf_info->proghdrs);
- kfree(elf_info->sechdrs);
- memset(elf_info, 0, sizeof(*elf_info));
-}
-/**
- * build_elf_exec_info - read ELF executable and check that we can use it
- */
-static int build_elf_exec_info(const char *buf, size_t len, struct elfhdr *ehdr,
- struct elf_info *elf_info)
-{
- int i;
- int ret;
-
- ret = elf_read_from_buffer(buf, len, ehdr, elf_info);
- if (ret)
- return ret;
-
- /* Big endian vmlinux has type ET_DYN. */
- if (ehdr->e_type != ET_EXEC && ehdr->e_type != ET_DYN) {
- pr_err("Not an ELF executable.\n");
- goto error;
- } else if (!elf_info->proghdrs) {
- pr_err("No ELF program header.\n");
- goto error;
- }
-
- for (i = 0; i < ehdr->e_phnum; i++) {
- /*
- * Kexec does not support loading interpreters.
- * In addition this check keeps us from attempting
- * to kexec ordinay executables.
- */
- if (elf_info->proghdrs[i].p_type == PT_INTERP) {
- pr_err("Requires an ELF interpreter.\n");
- goto error;
- }
- }
-
- return 0;
-error:
- elf_free_info(elf_info);
- return -ENOEXEC;
-}
-
static int elf64_probe(const char *buf, unsigned long len)
{
struct elfhdr ehdr;
diff --git a/include/linux/elf.h b/include/linux/elf.h
index ba069e8f4f78..e758bb4365c1 100644
--- a/include/linux/elf.h
+++ b/include/linux/elf.h
@@ -1,6 +1,8 @@
#ifndef _LINUX_ELF_H
#define _LINUX_ELF_H
+#include <linux/types.h>
+#include <asm/byteorder.h>
#include <asm/elf.h>
#include <uapi/linux/elf.h>
@@ -55,4 +57,64 @@ static inline int elf_coredump_extra_notes_write(struct coredump_params *cprm) {
extern int elf_coredump_extra_notes_size(void);
extern int elf_coredump_extra_notes_write(struct coredump_params *cprm);
#endif
+
+static inline u16 elf16_to_cpu(const struct elfhdr *ehdr, u16 value)
+{
+ if (ehdr->e_ident[EI_DATA] == ELFDATA2LSB)
+ value = le16_to_cpu(value);
+ else if (ehdr->e_ident[EI_DATA] == ELFDATA2MSB)
+ value = be16_to_cpu(value);
+
+ return value;
+}
+
+static inline u16 cpu_to_elf16(const struct elfhdr *ehdr, u16 value)
+{
+ if (ehdr->e_ident[EI_DATA] == ELFDATA2LSB)
+ value = cpu_to_le16(value);
+ else if (ehdr->e_ident[EI_DATA] == ELFDATA2MSB)
+ value = cpu_to_be16(value);
+
+ return value;
+}
+
+static inline u32 elf32_to_cpu(const struct elfhdr *ehdr, u32 value)
+{
+ if (ehdr->e_ident[EI_DATA] == ELFDATA2LSB)
+ value = le32_to_cpu(value);
+ else if (ehdr->e_ident[EI_DATA] == ELFDATA2MSB)
+ value = be32_to_cpu(value);
+
+ return value;
+}
+
+static inline u32 cpu_to_elf32(const struct elfhdr *ehdr, u32 value)
+{
+ if (ehdr->e_ident[EI_DATA] == ELFDATA2LSB)
+ value = cpu_to_le32(value);
+ else if (ehdr->e_ident[EI_DATA] == ELFDATA2MSB)
+ value = cpu_to_be32(value);
+
+ return value;
+}
+
+static inline u64 elf64_to_cpu(const struct elfhdr *ehdr, u64 value)
+{
+ if (ehdr->e_ident[EI_DATA] == ELFDATA2LSB)
+ value = le64_to_cpu(value);
+ else if (ehdr->e_ident[EI_DATA] == ELFDATA2MSB)
+ value = be64_to_cpu(value);
+
+ return value;
+}
+
+static inline u64 cpu_to_elf64(const struct elfhdr *ehdr, u64 value)
+{
+ if (ehdr->e_ident[EI_DATA] == ELFDATA2LSB)
+ value = cpu_to_le64(value);
+ else if (ehdr->e_ident[EI_DATA] == ELFDATA2MSB)
+ value = cpu_to_be64(value);
+
+ return value;
+}
#endif /* _LINUX_ELF_H */
diff --git a/include/linux/kexec.h b/include/linux/kexec.h
index dd056fab9e35..db98e3459e90 100644
--- a/include/linux/kexec.h
+++ b/include/linux/kexec.h
@@ -22,6 +22,7 @@
#ifdef CONFIG_KEXEC_CORE
#include <linux/list.h>
#include <linux/compat.h>
+#include <linux/elf.h>
#include <linux/ioport.h>
#include <linux/module.h>
#include <asm/kexec.h>
@@ -162,6 +163,24 @@ int __weak arch_kexec_walk_mem(struct kexec_buf *kbuf,
int (*func)(u64, u64, void *));
extern int kexec_add_buffer(struct kexec_buf *kbuf);
int kexec_locate_mem_hole(struct kexec_buf *kbuf);
+
+#ifdef CONFIG_KEXEC_FILE_ELF
+struct elf_info {
+ /*
+ * Where the ELF binary contents are kept.
+ * Memory managed by the user of the struct.
+ */
+ const char *buffer;
+
+ const struct elfhdr *ehdr;
+ const struct elf_phdr *proghdrs;
+ struct elf_shdr *sechdrs;
+};
+
+extern void elf_free_info(struct elf_info *elf_info);
+extern int build_elf_exec_info(const char *buf, size_t len, struct elfhdr *ehdr,
+ struct elf_info *elf_info);
+#endif /* CONFIG_KEXEC_FILE_ELF */
#endif /* CONFIG_KEXEC_FILE */
struct kimage {
diff --git a/kernel/Makefile b/kernel/Makefile
index d5f9748ab19f..d07492eb3804 100644
--- a/kernel/Makefile
+++ b/kernel/Makefile
@@ -63,6 +63,7 @@ obj-$(CONFIG_CRASH_CORE) += crash_core.o
obj-$(CONFIG_KEXEC_CORE) += kexec_core.o
obj-$(CONFIG_KEXEC) += kexec.o
obj-$(CONFIG_KEXEC_FILE) += kexec_file.o
+obj-$(CONFIG_KEXEC_FILE_ELF) += kexec_file_elf.o
obj-$(CONFIG_BACKTRACE_SELF_TEST) += backtracetest.o
obj-$(CONFIG_COMPAT) += compat.o
obj-$(CONFIG_CGROUPS) += cgroup/
diff --git a/kernel/kexec_file_elf.c b/kernel/kexec_file_elf.c
new file mode 100644
index 000000000000..4fc049e9731b
--- /dev/null
+++ b/kernel/kexec_file_elf.c
@@ -0,0 +1,454 @@
+/*
+ * Load ELF vmlinux file for the kexec_file_load syscall.
+ *
+ * Copyright (C) 2004 Adam Litke (agl@us.ibm.com)
+ * Copyright (C) 2004 IBM Corp.
+ * Copyright (C) 2005 R Sharada (sharada@in.ibm.com)
+ * Copyright (C) 2006 Mohan Kumar M (mohan@in.ibm.com)
+ * Copyright (C) 2016 IBM Corporation
+ *
+ * Based on kexec-tools' kexec-elf-exec.c and kexec-elf-ppc64.c.
+ * Heavily modified for the kernel by
+ * Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com>.
+ * Factored out for general use by
+ * AKASHI Takahiro <takahiro.akashi@linaro.org>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation (version 2 of the License).
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ */
+
+#define pr_fmt(fmt) "kexec_elf_elf: " fmt
+
+#include <linux/elf.h>
+#include <linux/errno.h>
+#include <linux/kexec.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/types.h>
+#include <asm/byteorder.h>
+
+#if ELF_CLASS == ELFCLASS32
+#define elf_addr_to_cpu elf32_to_cpu
+#else
+#define elf_addr_to_cpu elf64_to_cpu
+#endif
+
+/**
+ * elf_is_ehdr_sane - check that it is safe to use the ELF header
+ * @buf_len: size of the buffer in which the ELF file is loaded.
+ */
+static bool elf_is_ehdr_sane(const struct elfhdr *ehdr, size_t buf_len)
+{
+ if (ehdr->e_phnum > 0 && ehdr->e_phentsize != sizeof(struct elf_phdr)) {
+ pr_debug("Bad program header size.\n");
+ return false;
+ } else if (ehdr->e_shnum > 0 &&
+ ehdr->e_shentsize != sizeof(struct elf_shdr)) {
+ pr_debug("Bad section header size.\n");
+ return false;
+ } else if (ehdr->e_ident[EI_VERSION] != EV_CURRENT ||
+ ehdr->e_version != EV_CURRENT) {
+ pr_debug("Unknown ELF version.\n");
+ return false;
+ }
+
+ if (ehdr->e_phoff > 0 && ehdr->e_phnum > 0) {
+ size_t phdr_size;
+
+ /*
+ * e_phnum is at most 65535 so calculating the size of the
+ * program header cannot overflow.
+ */
+ phdr_size = sizeof(struct elf_phdr) * ehdr->e_phnum;
+
+ /* Sanity check the program header table location. */
+ if (ehdr->e_phoff + phdr_size < ehdr->e_phoff) {
+ pr_debug("Program headers at invalid location.\n");
+ return false;
+ } else if (ehdr->e_phoff + phdr_size > buf_len) {
+ pr_debug("Program headers truncated.\n");
+ return false;
+ }
+ }
+
+ if (ehdr->e_shoff > 0 && ehdr->e_shnum > 0) {
+ size_t shdr_size;
+
+ /*
+ * e_shnum is at most 65536 so calculating
+ * the size of the section header cannot overflow.
+ */
+ shdr_size = sizeof(struct elf_shdr) * ehdr->e_shnum;
+
+ /* Sanity check the section header table location. */
+ if (ehdr->e_shoff + shdr_size < ehdr->e_shoff) {
+ pr_debug("Section headers at invalid location.\n");
+ return false;
+ } else if (ehdr->e_shoff + shdr_size > buf_len) {
+ pr_debug("Section headers truncated.\n");
+ return false;
+ }
+ }
+
+ return true;
+}
+
+static int elf_read_ehdr(const char *buf, size_t len, struct elfhdr *ehdr)
+{
+ struct elfhdr *buf_ehdr;
+
+ if (len < sizeof(*buf_ehdr)) {
+ pr_debug("Buffer is too small to hold ELF header.\n");
+ return -ENOEXEC;
+ }
+
+ memset(ehdr, 0, sizeof(*ehdr));
+ memcpy(ehdr->e_ident, buf, sizeof(ehdr->e_ident));
+ if (memcmp(ehdr->e_ident, ELFMAG, SELFMAG)) {
+ pr_debug("No ELF header magic.\n");
+ return -ENOEXEC;
+ }
+
+ if (ehdr->e_ident[EI_CLASS] != ELF_CLASS) {
+ pr_debug("Not a supported ELF class.\n");
+ return -ENOEXEC;
+ } else if (ehdr->e_ident[EI_DATA] != ELFDATA2LSB &&
+ ehdr->e_ident[EI_DATA] != ELFDATA2MSB) {
+ pr_debug("Not a supported ELF data format.\n");
+ return -ENOEXEC;
+ }
+
+ buf_ehdr = (struct elfhdr *) buf;
+ if (elf16_to_cpu(ehdr, buf_ehdr->e_ehsize) != sizeof(*buf_ehdr)) {
+ pr_debug("Bad ELF header size.\n");
+ return -ENOEXEC;
+ }
+
+ ehdr->e_type = elf16_to_cpu(ehdr, buf_ehdr->e_type);
+ ehdr->e_machine = elf16_to_cpu(ehdr, buf_ehdr->e_machine);
+ ehdr->e_version = elf32_to_cpu(ehdr, buf_ehdr->e_version);
+ ehdr->e_entry = elf_addr_to_cpu(ehdr, buf_ehdr->e_entry);
+ ehdr->e_phoff = elf_addr_to_cpu(ehdr, buf_ehdr->e_phoff);
+ ehdr->e_shoff = elf_addr_to_cpu(ehdr, buf_ehdr->e_shoff);
+ ehdr->e_flags = elf32_to_cpu(ehdr, buf_ehdr->e_flags);
+ ehdr->e_phentsize = elf16_to_cpu(ehdr, buf_ehdr->e_phentsize);
+ ehdr->e_phnum = elf16_to_cpu(ehdr, buf_ehdr->e_phnum);
+ ehdr->e_shentsize = elf16_to_cpu(ehdr, buf_ehdr->e_shentsize);
+ ehdr->e_shnum = elf16_to_cpu(ehdr, buf_ehdr->e_shnum);
+ ehdr->e_shstrndx = elf16_to_cpu(ehdr, buf_ehdr->e_shstrndx);
+
+ return elf_is_ehdr_sane(ehdr, len) ? 0 : -ENOEXEC;
+}
+
+/**
+ * elf_is_phdr_sane - check that it is safe to use the program header
+ * @buf_len: size of the buffer in which the ELF file is loaded.
+ */
+static bool elf_is_phdr_sane(const struct elf_phdr *phdr, size_t buf_len)
+{
+
+ if (phdr->p_offset + phdr->p_filesz < phdr->p_offset) {
+ pr_debug("ELF segment location wraps around.\n");
+ return false;
+ } else if (phdr->p_offset + phdr->p_filesz > buf_len) {
+ pr_debug("ELF segment not in file.\n");
+ return false;
+ } else if (phdr->p_paddr + phdr->p_memsz < phdr->p_paddr) {
+ pr_debug("ELF segment address wraps around.\n");
+ return false;
+ }
+
+ return true;
+}
+
+static int elf_read_phdr(const char *buf, size_t len, struct elf_info *elf_info,
+ int idx)
+{
+ /* Override the const in proghdrs, we are the ones doing the loading. */
+ struct elf_phdr *phdr = (struct elf_phdr *) &elf_info->proghdrs[idx];
+ const char *pbuf;
+ struct elf_phdr *buf_phdr;
+
+ pbuf = buf + elf_info->ehdr->e_phoff + (idx * sizeof(*buf_phdr));
+ buf_phdr = (struct elf_phdr *) pbuf;
+
+ phdr->p_type = elf32_to_cpu(elf_info->ehdr, buf_phdr->p_type);
+ phdr->p_offset = elf_addr_to_cpu(elf_info->ehdr, buf_phdr->p_offset);
+ phdr->p_paddr = elf_addr_to_cpu(elf_info->ehdr, buf_phdr->p_paddr);
+ phdr->p_vaddr = elf_addr_to_cpu(elf_info->ehdr, buf_phdr->p_vaddr);
+ phdr->p_flags = elf32_to_cpu(elf_info->ehdr, buf_phdr->p_flags);
+
+ /*
+ * The following fields have a type equivalent to Elf_Addr
+ * both in 32 bit and 64 bit ELF.
+ */
+ phdr->p_filesz = elf_addr_to_cpu(elf_info->ehdr, buf_phdr->p_filesz);
+ phdr->p_memsz = elf_addr_to_cpu(elf_info->ehdr, buf_phdr->p_memsz);
+ phdr->p_align = elf_addr_to_cpu(elf_info->ehdr, buf_phdr->p_align);
+
+ return elf_is_phdr_sane(phdr, len) ? 0 : -ENOEXEC;
+}
+
+/**
+ * elf_read_phdrs - read the program headers from the buffer
+ *
+ * This function assumes that the program header table was checked for sanity.
+ * Use elf_is_ehdr_sane() if it wasn't.
+ */
+static int elf_read_phdrs(const char *buf, size_t len,
+ struct elf_info *elf_info)
+{
+ size_t phdr_size, i;
+ const struct elfhdr *ehdr = elf_info->ehdr;
+
+ /*
+ * e_phnum is at most 65535 so calculating the size of the
+ * program header cannot overflow.
+ */
+ phdr_size = sizeof(struct elf_phdr) * ehdr->e_phnum;
+
+ elf_info->proghdrs = kzalloc(phdr_size, GFP_KERNEL);
+ if (!elf_info->proghdrs)
+ return -ENOMEM;
+
+ for (i = 0; i < ehdr->e_phnum; i++) {
+ int ret;
+
+ ret = elf_read_phdr(buf, len, elf_info, i);
+ if (ret) {
+ kfree(elf_info->proghdrs);
+ elf_info->proghdrs = NULL;
+ return ret;
+ }
+ }
+
+ return 0;
+}
+
+/**
+ * elf_is_shdr_sane - check that it is safe to use the section header
+ * @buf_len: size of the buffer in which the ELF file is loaded.
+ */
+static bool elf_is_shdr_sane(const struct elf_shdr *shdr, size_t buf_len)
+{
+ bool size_ok;
+
+ /* SHT_NULL headers have undefined values, so we can't check them. */
+ if (shdr->sh_type == SHT_NULL)
+ return true;
+
+ /* Now verify sh_entsize */
+ switch (shdr->sh_type) {
+ case SHT_SYMTAB:
+ size_ok = shdr->sh_entsize == sizeof(Elf_Sym);
+ break;
+#ifdef Elf_Rela
+ case SHT_RELA:
+ size_ok = shdr->sh_entsize == sizeof(Elf_Rela);
+ break;
+#endif
+ case SHT_DYNAMIC:
+ size_ok = shdr->sh_entsize == sizeof(Elf_Dyn);
+ break;
+#ifdef Elf_Rel
+ case SHT_REL:
+ size_ok = shdr->sh_entsize == sizeof(Elf_Rel);
+ break;
+#endif
+ case SHT_NOTE:
+ case SHT_PROGBITS:
+ case SHT_HASH:
+ case SHT_NOBITS:
+ default:
+ /*
+ * This is a section whose entsize requirements
+ * I don't care about. If I don't know about
+ * the section I can't care about it's entsize
+ * requirements.
+ */
+ size_ok = true;
+ break;
+ }
+
+ if (!size_ok) {
+ pr_debug("ELF section with wrong entry size.\n");
+ return false;
+ } else if (shdr->sh_addr + shdr->sh_size < shdr->sh_addr) {
+ pr_debug("ELF section address wraps around.\n");
+ return false;
+ }
+
+ if (shdr->sh_type != SHT_NOBITS) {
+ if (shdr->sh_offset + shdr->sh_size < shdr->sh_offset) {
+ pr_debug("ELF section location wraps around.\n");
+ return false;
+ } else if (shdr->sh_offset + shdr->sh_size > buf_len) {
+ pr_debug("ELF section not in file.\n");
+ return false;
+ }
+ }
+
+ return true;
+}
+
+static int elf_read_shdr(const char *buf, size_t len, struct elf_info *elf_info,
+ int idx)
+{
+ struct elf_shdr *shdr = &elf_info->sechdrs[idx];
+ const struct elfhdr *ehdr = elf_info->ehdr;
+ const char *sbuf;
+ struct elf_shdr *buf_shdr;
+
+ sbuf = buf + ehdr->e_shoff + idx * sizeof(*buf_shdr);
+ buf_shdr = (struct elf_shdr *) sbuf;
+
+ shdr->sh_name = elf32_to_cpu(ehdr, buf_shdr->sh_name);
+ shdr->sh_type = elf32_to_cpu(ehdr, buf_shdr->sh_type);
+ shdr->sh_addr = elf_addr_to_cpu(ehdr, buf_shdr->sh_addr);
+ shdr->sh_offset = elf_addr_to_cpu(ehdr, buf_shdr->sh_offset);
+ shdr->sh_link = elf32_to_cpu(ehdr, buf_shdr->sh_link);
+ shdr->sh_info = elf32_to_cpu(ehdr, buf_shdr->sh_info);
+
+ /*
+ * The following fields have a type equivalent to Elf_Addr
+ * both in 32 bit and 64 bit ELF.
+ */
+ shdr->sh_flags = elf_addr_to_cpu(ehdr, buf_shdr->sh_flags);
+ shdr->sh_size = elf_addr_to_cpu(ehdr, buf_shdr->sh_size);
+ shdr->sh_addralign = elf_addr_to_cpu(ehdr, buf_shdr->sh_addralign);
+ shdr->sh_entsize = elf_addr_to_cpu(ehdr, buf_shdr->sh_entsize);
+
+ return elf_is_shdr_sane(shdr, len) ? 0 : -ENOEXEC;
+}
+
+/**
+ * elf_read_shdrs - read the section headers from the buffer
+ *
+ * This function assumes that the section header table was checked for sanity.
+ * Use elf_is_ehdr_sane() if it wasn't.
+ */
+static int elf_read_shdrs(const char *buf, size_t len,
+ struct elf_info *elf_info)
+{
+ size_t shdr_size, i;
+
+ /*
+ * e_shnum is at most 65536 so calculating
+ * the size of the section header cannot overflow.
+ */
+ shdr_size = sizeof(struct elf_shdr) * elf_info->ehdr->e_shnum;
+
+ elf_info->sechdrs = kzalloc(shdr_size, GFP_KERNEL);
+ if (!elf_info->sechdrs)
+ return -ENOMEM;
+
+ for (i = 0; i < elf_info->ehdr->e_shnum; i++) {
+ int ret;
+
+ ret = elf_read_shdr(buf, len, elf_info, i);
+ if (ret) {
+ kfree(elf_info->sechdrs);
+ elf_info->sechdrs = NULL;
+ return ret;
+ }
+ }
+
+ return 0;
+}
+
+/**
+ * elf_read_from_buffer - read ELF file and sets up ELF header and ELF info
+ * @buf: Buffer to read ELF file from.
+ * @len: Size of @buf.
+ * @ehdr: Pointer to existing struct which will be populated.
+ * @elf_info: Pointer to existing struct which will be populated.
+ *
+ * This function allows reading ELF files with different byte order than
+ * the kernel, byte-swapping the fields as needed.
+ *
+ * Return:
+ * On success returns 0, and the caller should call elf_free_info(elf_info) to
+ * free the memory allocated for the section and program headers.
+ */
+static int elf_read_from_buffer(const char *buf, size_t len,
+ struct elfhdr *ehdr, struct elf_info *elf_info)
+{
+ int ret;
+
+ ret = elf_read_ehdr(buf, len, ehdr);
+ if (ret)
+ return ret;
+
+ elf_info->buffer = buf;
+ elf_info->ehdr = ehdr;
+ if (ehdr->e_phoff > 0 && ehdr->e_phnum > 0) {
+ ret = elf_read_phdrs(buf, len, elf_info);
+ if (ret)
+ return ret;
+ }
+ if (ehdr->e_shoff > 0 && ehdr->e_shnum > 0) {
+ ret = elf_read_shdrs(buf, len, elf_info);
+ if (ret) {
+ kfree(elf_info->proghdrs);
+ return ret;
+ }
+ }
+
+ return 0;
+}
+
+/**
+ * elf_free_info - free memory allocated by elf_read_from_buffer
+ */
+void elf_free_info(struct elf_info *elf_info)
+{
+ kfree(elf_info->proghdrs);
+ kfree(elf_info->sechdrs);
+ memset(elf_info, 0, sizeof(*elf_info));
+}
+
+/**
+ * build_elf_exec_info - read ELF executable and check that we can use it
+ */
+int build_elf_exec_info(const char *buf, size_t len, struct elfhdr *ehdr,
+ struct elf_info *elf_info)
+{
+ int i;
+ int ret;
+
+ ret = elf_read_from_buffer(buf, len, ehdr, elf_info);
+ if (ret)
+ return ret;
+
+ /* Big endian vmlinux has type ET_DYN. */
+ if (ehdr->e_type != ET_EXEC && ehdr->e_type != ET_DYN) {
+ pr_err("Not an ELF executable.\n");
+ goto error;
+ } else if (!elf_info->proghdrs) {
+ pr_err("No ELF program header.\n");
+ goto error;
+ }
+
+ for (i = 0; i < ehdr->e_phnum; i++) {
+ /*
+ * Kexec does not support loading interpreters.
+ * In addition this check keeps us from attempting
+ * to kexec ordinary executables.
+ */
+ if (elf_info->proghdrs[i].p_type == PT_INTERP) {
+ pr_err("Requires an ELF interpreter.\n");
+ goto error;
+ }
+ }
+
+ return 0;
+error:
+ elf_free_info(elf_info);
+ return -ENOEXEC;
+}
--
2.14.1
[toc] | [prev] | [next] | [standalone]
| From | AKASHI Takahiro <takahiro.akashi@linaro.org> |
|---|---|
| Date | 2017-08-24 10:30 +0200 |
| Subject | [PATCH 05/14] kexec_file: factor out crashdump elf header function from x86 |
| Message-ID | <uhVGz-405-43@gated-at.bofh.it> |
| In reply to | #1718948 |
prepare_elf_headers() can also be useful for other architectures,
including arm64. So let it factored out.
Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org>
Cc: Dave Young <dyoung@redhat.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: Baoquan He <bhe@redhat.com>
---
arch/x86/kernel/crash.c | 324 ----------------------------------------------
include/linux/kexec.h | 19 +++
kernel/crash_core.c | 333 ++++++++++++++++++++++++++++++++++++++++++++++++
3 files changed, 352 insertions(+), 324 deletions(-)
diff --git a/arch/x86/kernel/crash.c b/arch/x86/kernel/crash.c
index 44404e2307bb..3c6b880f6dbf 100644
--- a/arch/x86/kernel/crash.c
+++ b/arch/x86/kernel/crash.c
@@ -21,7 +21,6 @@
#include <linux/elf.h>
#include <linux/elfcore.h>
#include <linux/export.h>
-#include <linux/slab.h>
#include <linux/vmalloc.h>
#include <asm/processor.h>
@@ -41,34 +40,6 @@
/* Alignment required for elf header segment */
#define ELF_CORE_HEADER_ALIGN 4096
-/* This primarily represents number of split ranges due to exclusion */
-#define CRASH_MAX_RANGES 16
-
-struct crash_mem_range {
- u64 start, end;
-};
-
-struct crash_mem {
- unsigned int nr_ranges;
- struct crash_mem_range ranges[CRASH_MAX_RANGES];
-};
-
-/* Misc data about ram ranges needed to prepare elf headers */
-struct crash_elf_data {
- struct kimage *image;
- /*
- * Total number of ram ranges we have after various adjustments for
- * crash reserved region, etc.
- */
- unsigned int max_nr_ranges;
-
- /* Pointer to elf header */
- void *ehdr;
- /* Pointer to next phdr */
- void *bufp;
- struct crash_mem mem;
-};
-
/* Used while preparing memory map entries for second kernel */
struct crash_memmap_data {
struct boot_params *params;
@@ -209,301 +180,6 @@ void native_machine_crash_shutdown(struct pt_regs *regs)
}
#ifdef CONFIG_KEXEC_FILE
-static int get_nr_ram_ranges_callback(u64 start, u64 end, void *arg)
-{
- unsigned int *nr_ranges = arg;
-
- (*nr_ranges)++;
- return 0;
-}
-
-
-/* Gather all the required information to prepare elf headers for ram regions */
-static void fill_up_crash_elf_data(struct crash_elf_data *ced,
- struct kimage *image)
-{
- unsigned int nr_ranges = 0;
-
- ced->image = image;
-
- walk_system_ram_res(0, -1, &nr_ranges,
- get_nr_ram_ranges_callback);
-
- ced->max_nr_ranges = nr_ranges;
-
- /* Exclusion of crash region could split memory ranges */
- ced->max_nr_ranges++;
-
- /* If crashk_low_res is not 0, another range split possible */
- if (crashk_low_res.end)
- ced->max_nr_ranges++;
-}
-
-static int exclude_mem_range(struct crash_mem *mem,
- unsigned long long mstart, unsigned long long mend)
-{
- int i, j;
- unsigned long long start, 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;
-
- if (mstart > end || mend < start)
- continue;
-
- /* Truncate any area outside of range */
- if (mstart < start)
- mstart = start;
- if (mend > end)
- mend = end;
-
- /* Found completely overlapping range */
- if (mstart == start && mend == 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;
- }
- }
- mem->nr_ranges--;
- return 0;
- }
-
- if (mstart > start && mend < end) {
- /* Split original range */
- mem->ranges[i].end = mstart - 1;
- temp_range.start = mend + 1;
- temp_range.end = end;
- } else if (mstart != start)
- mem->ranges[i].end = mstart - 1;
- else
- mem->ranges[i].start = mend + 1;
- break;
- }
-
- /* If a split happend, add the split to array */
- if (!temp_range.end)
- return 0;
-
- /* Split happened */
- if (i == CRASH_MAX_RANGES - 1) {
- pr_err("Too many crash ranges after split\n");
- 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;
-}
-
-/*
- * Look for any unwanted ranges between mstart, mend and remove them. This
- * might lead to split and split ranges are put in ced->mem.ranges[] array
- */
-static int elf_header_exclude_ranges(struct crash_elf_data *ced,
- unsigned long long mstart, unsigned long long mend)
-{
- struct crash_mem *cmem = &ced->mem;
- int ret = 0;
-
- memset(cmem->ranges, 0, sizeof(cmem->ranges));
-
- cmem->ranges[0].start = mstart;
- cmem->ranges[0].end = mend;
- cmem->nr_ranges = 1;
-
- /* Exclude crashkernel region */
- ret = exclude_mem_range(cmem, crashk_res.start, crashk_res.end);
- if (ret)
- return ret;
-
- if (crashk_low_res.end) {
- ret = exclude_mem_range(cmem, crashk_low_res.start, crashk_low_res.end);
- if (ret)
- return ret;
- }
-
- return ret;
-}
-
-static int prepare_elf64_ram_headers_callback(u64 start, u64 end, void *arg)
-{
- struct crash_elf_data *ced = arg;
- Elf64_Ehdr *ehdr;
- Elf64_Phdr *phdr;
- unsigned long mstart, mend;
- struct kimage *image = ced->image;
- struct crash_mem *cmem;
- int ret, i;
-
- ehdr = ced->ehdr;
-
- /* Exclude unwanted mem ranges */
- ret = elf_header_exclude_ranges(ced, start, end);
- if (ret)
- return ret;
-
- /* Go through all the ranges in ced->mem.ranges[] and prepare phdr */
- cmem = &ced->mem;
-
- for (i = 0; i < cmem->nr_ranges; i++) {
- mstart = cmem->ranges[i].start;
- mend = cmem->ranges[i].end;
-
- phdr = ced->bufp;
- ced->bufp += sizeof(Elf64_Phdr);
-
- phdr->p_type = PT_LOAD;
- phdr->p_flags = PF_R|PF_W|PF_X;
- phdr->p_offset = mstart;
-
- /*
- * If a range matches backup region, adjust offset to backup
- * segment.
- */
- if (mstart == image->arch.backup_src_start &&
- (mend - mstart + 1) == image->arch.backup_src_sz)
- phdr->p_offset = image->arch.backup_load_addr;
-
- phdr->p_paddr = mstart;
- phdr->p_vaddr = (unsigned long long) __va(mstart);
- phdr->p_filesz = phdr->p_memsz = mend - mstart + 1;
- phdr->p_align = 0;
- ehdr->e_phnum++;
- 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);
- }
-
- return ret;
-}
-
-static int prepare_elf64_headers(struct crash_elf_data *ced,
- 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, *bufp;
- unsigned int cpu;
- unsigned long long notes_addr;
- int ret;
-
- /* extra phdr for vmcoreinfo elf note */
- nr_phdr = nr_cpus + 1;
- nr_phdr += ced->max_nr_ranges;
-
- /*
- * kexec-tools creates an extra PT_LOAD phdr for kernel text mapping
- * area on x86_64 (ffffffff80000000 - ffffffffa0000000).
- * I think this is required by tools like gdb. So same physical
- * 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;
-
- bufp = buf;
- ehdr = (Elf64_Ehdr *)bufp;
- bufp += sizeof(Elf64_Ehdr);
- 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 = (Elf64_Phdr *)bufp;
- bufp += sizeof(Elf64_Phdr);
- 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)++;
- }
-
- /* Prepare one PT_NOTE header for vmcoreinfo */
- phdr = (Elf64_Phdr *)bufp;
- bufp += sizeof(Elf64_Phdr);
- 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)++;
-
-#ifdef CONFIG_X86_64
- /* Prepare PT_LOAD type program header for kernel text region */
- phdr = (Elf64_Phdr *)bufp;
- bufp += sizeof(Elf64_Phdr);
- phdr->p_type = PT_LOAD;
- phdr->p_flags = PF_R|PF_W|PF_X;
- phdr->p_vaddr = (Elf64_Addr)_text;
- phdr->p_filesz = phdr->p_memsz = _end - _text;
- phdr->p_offset = phdr->p_paddr = __pa_symbol(_text);
- (ehdr->e_phnum)++;
-#endif
-
- /* Prepare PT_LOAD headers for system ram chunks. */
- ced->ehdr = ehdr;
- ced->bufp = bufp;
- ret = walk_system_ram_res(0, -1, ced,
- prepare_elf64_ram_headers_callback);
- if (ret < 0)
- return ret;
-
- *addr = buf;
- *sz = elf_sz;
- return 0;
-}
-
-/* Prepare elf headers. Return addr and size */
-static int prepare_elf_headers(struct kimage *image, void **addr,
- unsigned long *sz)
-{
- struct crash_elf_data *ced;
- int ret;
-
- ced = kzalloc(sizeof(*ced), GFP_KERNEL);
- if (!ced)
- return -ENOMEM;
-
- fill_up_crash_elf_data(ced, image);
-
- /* By default prepare 64bit headers */
- ret = prepare_elf64_headers(ced, addr, sz);
- kfree(ced);
- return ret;
-}
-
static int add_e820_entry(struct boot_params *params, struct e820_entry *entry)
{
unsigned int nr_e820_entries;
diff --git a/include/linux/kexec.h b/include/linux/kexec.h
index db98e3459e90..acaecd72b134 100644
--- a/include/linux/kexec.h
+++ b/include/linux/kexec.h
@@ -163,6 +163,25 @@ int __weak arch_kexec_walk_mem(struct kexec_buf *kbuf,
int (*func)(u64, u64, void *));
extern int kexec_add_buffer(struct kexec_buf *kbuf);
int kexec_locate_mem_hole(struct kexec_buf *kbuf);
+#ifdef CONFIG_CRASH_CORE
+extern int prepare_elf_headers(struct kimage *image, void **addr,
+ unsigned long *sz);
+
+/* This primarily represents number of split ranges due to exclusion */
+#define CRASH_MAX_RANGES 16
+
+struct crash_mem_range {
+ u64 start, end;
+};
+
+struct crash_mem {
+ unsigned int nr_ranges;
+ struct crash_mem_range ranges[CRASH_MAX_RANGES];
+};
+
+extern int exclude_mem_range(struct crash_mem *mem,
+ unsigned long long mstart, unsigned long long mend);
+#endif
#ifdef CONFIG_KEXEC_FILE_ELF
struct elf_info {
diff --git a/kernel/crash_core.c b/kernel/crash_core.c
index 6db80fc0810b..f2385590e94b 100644
--- a/kernel/crash_core.c
+++ b/kernel/crash_core.c
@@ -7,6 +7,11 @@
*/
#include <linux/crash_core.h>
+#include <linux/elf.h>
+#include <linux/elfcore.h>
+#include <linux/kernel.h>
+#include <linux/kexec.h>
+#include <linux/slab.h>
#include <linux/utsname.h>
#include <linux/vmalloc.h>
@@ -469,3 +474,331 @@ static int __init crash_save_vmcoreinfo_init(void)
}
subsys_initcall(crash_save_vmcoreinfo_init);
+
+#ifdef CONFIG_KEXEC_FILE
+/*
+ * The following definitions are for local use only.
+ */
+
+/* Alignment required for elf header segment */
+#define ELF_CORE_HEADER_ALIGN 4096
+
+/* Misc data about ram ranges needed to prepare elf headers */
+struct crash_elf_data {
+ struct kimage *image;
+ /*
+ * Total number of ram ranges we have after various adjustments for
+ * crash reserved region, etc.
+ */
+ unsigned int max_nr_ranges;
+
+ /* Pointer to elf header */
+ void *ehdr;
+ /* Pointer to next phdr */
+ void *bufp;
+ struct crash_mem mem;
+};
+
+static int get_nr_ram_ranges_callback(u64 start, u64 end, void *arg)
+{
+ unsigned int *nr_ranges = arg;
+
+ (*nr_ranges)++;
+ return 0;
+}
+
+
+/* Gather all the required information to prepare elf headers for ram regions */
+static void fill_up_crash_elf_data(struct crash_elf_data *ced,
+ struct kimage *image)
+{
+ unsigned int nr_ranges = 0;
+
+ ced->image = image;
+
+ walk_system_ram_res(0, -1, &nr_ranges,
+ get_nr_ram_ranges_callback);
+
+ ced->max_nr_ranges = nr_ranges;
+
+ /* Exclusion of crash region could split memory ranges */
+ ced->max_nr_ranges++;
+
+#ifdef CONFIG_X86_64
+ /* If crashk_low_res is not 0, another range split possible */
+ if (crashk_low_res.end)
+ ced->max_nr_ranges++;
+#endif
+}
+
+int exclude_mem_range(struct crash_mem *mem,
+ unsigned long long mstart, unsigned long long mend)
+{
+ int i, j;
+ unsigned long long start, 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;
+
+ if (mstart > end || mend < start)
+ continue;
+
+ /* Truncate any area outside of range */
+ if (mstart < start)
+ mstart = start;
+ if (mend > end)
+ mend = end;
+
+ /* Found completely overlapping range */
+ if (mstart == start && mend == 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;
+ }
+ }
+ mem->nr_ranges--;
+ return 0;
+ }
+
+ if (mstart > start && mend < end) {
+ /* Split original range */
+ mem->ranges[i].end = mstart - 1;
+ temp_range.start = mend + 1;
+ temp_range.end = end;
+ } else if (mstart != start)
+ mem->ranges[i].end = mstart - 1;
+ else
+ mem->ranges[i].start = mend + 1;
+ break;
+ }
+
+ /* If a split happened, add the split to array */
+ if (!temp_range.end)
+ return 0;
+
+ /* Split happened */
+ if (i == CRASH_MAX_RANGES - 1) {
+ pr_err("Too many crash ranges after split\n");
+ 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;
+}
+
+/*
+ * Look for any unwanted ranges between mstart, mend and remove them. This
+ * might lead to split and split ranges are put in ced->mem.ranges[] array
+ */
+static int elf_header_exclude_ranges(struct crash_elf_data *ced,
+ unsigned long long mstart, unsigned long long mend)
+{
+ struct crash_mem *cmem = &ced->mem;
+ int ret = 0;
+
+ memset(cmem->ranges, 0, sizeof(cmem->ranges));
+
+ cmem->ranges[0].start = mstart;
+ cmem->ranges[0].end = mend;
+ cmem->nr_ranges = 1;
+
+ /* Exclude crashkernel region */
+ ret = exclude_mem_range(cmem, crashk_res.start, crashk_res.end);
+ if (ret)
+ return ret;
+
+#ifdef CONFIG_X86_64
+ if (crashk_low_res.end) {
+ ret = exclude_mem_range(cmem, crashk_low_res.start,
+ crashk_low_res.end);
+ if (ret)
+ return ret;
+ }
+#endif
+
+ return ret;
+}
+
+static int prepare_elf64_ram_headers_callback(u64 start, u64 end, void *arg)
+{
+ struct crash_elf_data *ced = arg;
+ Elf64_Ehdr *ehdr;
+ Elf64_Phdr *phdr;
+ unsigned long mstart, mend;
+#ifdef CONFIG_X86_64
+ struct kimage *image = ced->image;
+#endif
+ struct crash_mem *cmem;
+ int ret, i;
+
+ ehdr = ced->ehdr;
+
+ /* Exclude unwanted mem ranges */
+ ret = elf_header_exclude_ranges(ced, start, end);
+ if (ret)
+ return ret;
+
+ /* Go through all the ranges in ced->mem.ranges[] and prepare phdr */
+ cmem = &ced->mem;
+
+ for (i = 0; i < cmem->nr_ranges; i++) {
+ mstart = cmem->ranges[i].start;
+ mend = cmem->ranges[i].end;
+
+ phdr = ced->bufp;
+ ced->bufp += sizeof(Elf64_Phdr);
+
+ phdr->p_type = PT_LOAD;
+ phdr->p_flags = PF_R|PF_W|PF_X;
+ phdr->p_offset = mstart;
+
+#ifdef CONFIG_X86_64
+ /*
+ * If a range matches backup region, adjust offset to backup
+ * segment.
+ */
+ if (mstart == image->arch.backup_src_start &&
+ (mend - mstart + 1) == image->arch.backup_src_sz)
+ phdr->p_offset = image->arch.backup_load_addr;
+#endif
+
+ phdr->p_paddr = mstart;
+ phdr->p_vaddr = (unsigned long long) __va(mstart);
+ phdr->p_filesz = phdr->p_memsz = mend - mstart + 1;
+ phdr->p_align = 0;
+ ehdr->e_phnum++;
+ 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);
+ }
+
+ return ret;
+}
+
+static int prepare_elf64_headers(struct crash_elf_data *ced,
+ 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, *bufp;
+ unsigned int cpu;
+ unsigned long long notes_addr;
+ int ret;
+
+ /* extra phdr for vmcoreinfo elf note */
+ nr_phdr = nr_cpus + 1;
+ nr_phdr += ced->max_nr_ranges;
+
+ /*
+ * kexec-tools creates an extra PT_LOAD phdr for kernel text mapping
+ * area on x86_64 (ffffffff80000000 - ffffffffa0000000).
+ * I think this is required by tools like gdb. So same physical
+ * 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;
+
+ bufp = buf;
+ ehdr = (Elf64_Ehdr *)bufp;
+ bufp += sizeof(Elf64_Ehdr);
+ 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 = (Elf64_Phdr *)bufp;
+ bufp += sizeof(Elf64_Phdr);
+ 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)++;
+ }
+
+ /* Prepare one PT_NOTE header for vmcoreinfo */
+ phdr = (Elf64_Phdr *)bufp;
+ bufp += sizeof(Elf64_Phdr);
+ 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)++;
+
+#ifdef CONFIG_X86_64
+ /* Prepare PT_LOAD type program header for kernel text region */
+ phdr = (Elf64_Phdr *)bufp;
+ bufp += sizeof(Elf64_Phdr);
+ phdr->p_type = PT_LOAD;
+ phdr->p_flags = PF_R|PF_W|PF_X;
+ phdr->p_vaddr = (Elf64_Addr)_text;
+ phdr->p_filesz = phdr->p_memsz = _end - _text;
+ phdr->p_offset = phdr->p_paddr = __pa_symbol(_text);
+ (ehdr->e_phnum)++;
+#endif
+
+ /* Prepare PT_LOAD headers for system ram chunks. */
+ ced->ehdr = ehdr;
+ ced->bufp = bufp;
+ ret = walk_system_ram_res(0, -1, ced,
+ prepare_elf64_ram_headers_callback);
+ if (ret < 0)
+ return ret;
+
+ *addr = buf;
+ *sz = elf_sz;
+ return 0;
+}
+
+/* Prepare elf headers. Return addr and size */
+int prepare_elf_headers(struct kimage *image, void **addr, unsigned long *sz)
+{
+ struct crash_elf_data *ced;
+ int ret;
+
+ ced = kzalloc(sizeof(*ced), GFP_KERNEL);
+ if (!ced)
+ return -ENOMEM;
+
+ fill_up_crash_elf_data(ced, image);
+
+ /* By default prepare 64bit headers */
+ ret = prepare_elf64_headers(ced, addr, sz);
+ kfree(ced);
+ return ret;
+}
+#endif /* CONFIG_KEXEC_FILE */
--
2.14.1
[toc] | [prev] | [next] | [standalone]
| From | Dave Young <dyoung@redhat.com> |
|---|---|
| Date | 2017-08-25 07:50 +0200 |
| Subject | Re: [PATCH 05/14] kexec_file: factor out crashdump elf header function from x86 |
| Message-ID | <uifFg-8sr-3@gated-at.bofh.it> |
| In reply to | #1718975 |
On 08/24/17 at 05:18pm, AKASHI Takahiro wrote: > prepare_elf_headers() can also be useful for other architectures, > including arm64. So let it factored out. > > Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org> > Cc: Dave Young <dyoung@redhat.com> > Cc: Vivek Goyal <vgoyal@redhat.com> > Cc: Baoquan He <bhe@redhat.com> > --- > arch/x86/kernel/crash.c | 324 ---------------------------------------------- > include/linux/kexec.h | 19 +++ > kernel/crash_core.c | 333 ++++++++++++++++++++++++++++++++++++++++++++++++ It looks better to add these to kexec_file.c instead. Thanks Dave
[toc] | [prev] | [next] | [standalone]
| From | AKASHI Takahiro <takahiro.akashi@linaro.org> |
|---|---|
| Date | 2017-09-08 04:30 +0200 |
| Subject | Re: [PATCH 05/14] kexec_file: factor out crashdump elf header function from x86 |
| Message-ID | <unhdo-A0-9@gated-at.bofh.it> |
| In reply to | #1719762 |
On Fri, Aug 25, 2017 at 01:47:49PM +0800, Dave Young wrote: > On 08/24/17 at 05:18pm, AKASHI Takahiro wrote: > > prepare_elf_headers() can also be useful for other architectures, > > including arm64. So let it factored out. > > > > Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org> > > Cc: Dave Young <dyoung@redhat.com> > > Cc: Vivek Goyal <vgoyal@redhat.com> > > Cc: Baoquan He <bhe@redhat.com> > > --- > > arch/x86/kernel/crash.c | 324 ---------------------------------------------- > > include/linux/kexec.h | 19 +++ > > kernel/crash_core.c | 333 ++++++++++++++++++++++++++++++++++++++++++++++++ > > It looks better to add these to kexec_file.c instead. Sure -Takahiro AKASHI > Thanks > Dave
[toc] | [prev] | [next] | [standalone]
| From | AKASHI Takahiro <takahiro.akashi@linaro.org> |
|---|---|
| Date | 2017-08-24 10:30 +0200 |
| Subject | [PATCH 06/14] kexec_file: add kexec_add_segment() |
| Message-ID | <uhVGA-405-55@gated-at.bofh.it> |
| In reply to | #1718948 |
In contrast to kexec_add_buffer(), this function assumes that kbuf->mem
is already assigned by caller. This type of allocation is commonly used
in kexec-tools.
This function will be used on arm64 in loading vmlinux(elf) binary.
Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org>
Cc: Dave Young <dyoung@redhat.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: Baoquan He <bhe@redhat.com>
---
include/linux/kexec.h | 1 +
kernel/kexec_file.c | 47 +++++++++++++++++++++++++++++++++++++++++++++++
2 files changed, 48 insertions(+)
diff --git a/include/linux/kexec.h b/include/linux/kexec.h
index acaecd72b134..be5e99afaf77 100644
--- a/include/linux/kexec.h
+++ b/include/linux/kexec.h
@@ -162,6 +162,7 @@ struct kexec_buf {
int __weak arch_kexec_walk_mem(struct kexec_buf *kbuf,
int (*func)(u64, u64, void *));
extern int kexec_add_buffer(struct kexec_buf *kbuf);
+extern int kexec_add_segment(struct kexec_buf *kbuf);
int kexec_locate_mem_hole(struct kexec_buf *kbuf);
#ifdef CONFIG_CRASH_CORE
extern int prepare_elf_headers(struct kimage *image, void **addr,
diff --git a/kernel/kexec_file.c b/kernel/kexec_file.c
index 9f48f4412297..d898dec37816 100644
--- a/kernel/kexec_file.c
+++ b/kernel/kexec_file.c
@@ -519,6 +519,53 @@ int kexec_add_buffer(struct kexec_buf *kbuf)
return 0;
}
+/**
+ * kexec_add_segment - place a buffer in a kexec segment
+ * @kbuf: Buffer contents and memory parameters.
+ *
+ * In contrast to kexec_add_buffer(), this function assumes
+ * that kbuf->mem is already assigned by caller.
+ *
+ * Return: 0 on success, negative errno on error.
+ */
+int kexec_add_segment(struct kexec_buf *kbuf)
+{
+
+ struct kexec_segment *ksegment;
+
+ /* 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);
+
+ /* 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)
{
--
2.14.1
[toc] | [prev] | [next] | [standalone]
| From | AKASHI Takahiro <takahiro.akashi@linaro.org> |
|---|---|
| Date | 2017-08-24 10:30 +0200 |
| Subject | [PATCH 12/14] arm64: enable KEXEC_FILE config |
| Message-ID | <uhVGA-405-59@gated-at.bofh.it> |
| In reply to | #1718948 |
Modify arm64/Kconfig and Makefile to enable kexec_file_load support. Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will.deacon@arm.com> --- arch/arm64/Kconfig | 22 ++++++++++++++++++++++ arch/arm64/kernel/Makefile | 2 +- 2 files changed, 23 insertions(+), 1 deletion(-) diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig index dfd908630631..cf10bc720d9e 100644 --- a/arch/arm64/Kconfig +++ b/arch/arm64/Kconfig @@ -756,6 +756,28 @@ config KEXEC but it is independent of the system firmware. And like a reboot you can start any kernel with it, not just Linux. +config KEXEC_FILE + bool "kexec file based system call" + select KEXEC_CORE + select BUILD_BIN2C + ---help--- + This is new version of kexec system call. This system call is + file based and takes file descriptors as system call argument + for kernel and initramfs as opposed to list of segments as + accepted by previous system call. + +config KEXEC_VERIFY_SIG + bool "Verify kernel signature during kexec_file_load() syscall" + depends on KEXEC_FILE + select SYSTEM_DATA_VERIFICATION + ---help--- + This option makes kernel signature verification mandatory for + the kexec_file_load() syscall. + + In addition to that option, you need to enable signature + verification for the corresponding kernel image type being + loaded in order for this to work. + config CRASH_DUMP bool "Build kdump crash kernel" help diff --git a/arch/arm64/kernel/Makefile b/arch/arm64/kernel/Makefile index 16e9f56b536a..5df003d6157c 100644 --- a/arch/arm64/kernel/Makefile +++ b/arch/arm64/kernel/Makefile @@ -48,7 +48,7 @@ arm64-obj-$(CONFIG_ARM64_ACPI_PARKING_PROTOCOL) += acpi_parking_protocol.o arm64-obj-$(CONFIG_PARAVIRT) += paravirt.o arm64-obj-$(CONFIG_RANDOMIZE_BASE) += kaslr.o arm64-obj-$(CONFIG_HIBERNATION) += hibernate.o hibernate-asm.o -arm64-obj-$(CONFIG_KEXEC) += machine_kexec.o relocate_kernel.o \ +arm64-obj-$(CONFIG_KEXEC_CORE) += machine_kexec.o relocate_kernel.o \ cpu-reset.o arm64-obj-$(CONFIG_KEXEC_FILE) += machine_kexec_file.o arm64-obj-$(CONFIG_ARM64_RELOC_TEST) += arm64-reloc-test.o -- 2.14.1
[toc] | [prev] | [next] | [standalone]
| From | AKASHI Takahiro <takahiro.akashi@linaro.org> |
|---|---|
| Date | 2017-08-24 10:30 +0200 |
| Subject | [PATCH 11/14] arm64: kexec_file: set up for crash dump adding elf core header |
| Message-ID | <uhVGA-405-69@gated-at.bofh.it> |
| In reply to | #1718948 |
load_crashdump_segments() creates and loads a memory segment of elf core
header for crash dump.
"linux,usable-memory-range" and "linux,elfcorehdr" will add to the 2nd
kernel's device-tree blob. The logic of this cod is also from kexec-tools.
Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
---
arch/arm64/include/asm/kexec.h | 5 ++
arch/arm64/kernel/machine_kexec_file.c | 145 +++++++++++++++++++++++++++++++++
2 files changed, 150 insertions(+)
diff --git a/arch/arm64/include/asm/kexec.h b/arch/arm64/include/asm/kexec.h
index ebc4aaa707ae..46b21512efbe 100644
--- a/arch/arm64/include/asm/kexec.h
+++ b/arch/arm64/include/asm/kexec.h
@@ -98,6 +98,10 @@ static inline void crash_post_resume(void) {}
struct kimage_arch {
void *dtb_buf;
+ /* Core ELF header buffer */
+ void *elf_headers;
+ unsigned long elf_headers_sz;
+ unsigned long elf_load_addr;
};
struct kimage;
@@ -109,6 +113,7 @@ extern int load_other_segments(struct kimage *image,
unsigned long kernel_load_addr,
char *initrd, unsigned long initrd_len,
char *cmdline, unsigned long cmdline_len);
+extern int load_crashdump_segments(struct kimage *image);
#endif
#endif /* __ASSEMBLY__ */
diff --git a/arch/arm64/kernel/machine_kexec_file.c b/arch/arm64/kernel/machine_kexec_file.c
index cd12e451e474..012063307001 100644
--- a/arch/arm64/kernel/machine_kexec_file.c
+++ b/arch/arm64/kernel/machine_kexec_file.c
@@ -281,6 +281,77 @@ int arch_kexec_walk_mem(struct kexec_buf *kbuf, int (*func)(u64, u64, void *))
return walk_system_ram_res(0, ULONG_MAX, kbuf, func);
}
+static int __init arch_kexec_file_init(void)
+{
+ /* Those values are used later on loading the kernel */
+ __dt_root_addr_cells = dt_root_addr_cells;
+ __dt_root_size_cells = dt_root_size_cells;
+
+ return 0;
+}
+late_initcall(arch_kexec_file_init);
+
+#define FDT_ALIGN(x, a) (((x) + (a) - 1) & ~((a) - 1))
+#define FDT_TAGALIGN(x) (FDT_ALIGN((x), FDT_TAGSIZE))
+
+static int fdt_prop_len(const char *prop_name, int len)
+{
+ return (strlen(prop_name) + 1) +
+ sizeof(struct fdt_property) +
+ FDT_TAGALIGN(len);
+}
+
+static bool cells_size_fitted(unsigned long base, unsigned long size)
+{
+ /* if *_cells >= 2, cells can hold 64-bit values anyway */
+ if ((__dt_root_addr_cells == 1) && (base >= (1ULL << 32)))
+ return false;
+
+ if ((__dt_root_size_cells == 1) && (size >= (1ULL << 32)))
+ return false;
+
+ return true;
+}
+
+static void fill_property(void *buf, u64 val64, int cells)
+{
+ u32 val32;
+ int i;
+
+ if (cells == 1) {
+ val32 = cpu_to_fdt32((u32)val64);
+ memcpy(buf, &val32, sizeof(val32));
+ } else {
+ for (i = 0; i < (cells * sizeof(u32) - sizeof(u64)); i++)
+ *(char *)buf++ = 0;
+
+ val64 = cpu_to_fdt64(val64);
+ memcpy(buf, &val64, sizeof(val64));
+ }
+}
+
+static int fdt_setprop_range(void *fdt, int nodeoffset, const char *name,
+ unsigned long addr, unsigned long size)
+{
+ u64 range[2];
+ void *prop;
+ size_t buf_size;
+ int result;
+
+ prop = range;
+ buf_size = (__dt_root_addr_cells + __dt_root_size_cells) * sizeof(u32);
+
+ fill_property(prop, addr, __dt_root_addr_cells);
+ prop += __dt_root_addr_cells * sizeof(u32);
+
+ fill_property(prop, size, __dt_root_size_cells);
+ prop += __dt_root_size_cells * sizeof(u32);
+
+ result = fdt_setprop(fdt, nodeoffset, name, range, buf_size);
+
+ return result;
+}
+
int setup_dtb(struct kimage *image,
unsigned long initrd_load_addr, unsigned long initrd_len,
char *cmdline, unsigned long cmdline_len,
@@ -293,10 +364,26 @@ int setup_dtb(struct kimage *image,
int range_len;
int ret;
+ /* check ranges against root's #address-cells and #size-cells */
+ if (image->type == KEXEC_TYPE_CRASH &&
+ (!cells_size_fitted(image->arch.elf_load_addr,
+ image->arch.elf_headers_sz) ||
+ !cells_size_fitted(crashk_res.start,
+ crashk_res.end - crashk_res.start + 1))) {
+ pr_err("Crash memory region doesn't fit into DT's root cell sizes.\n");
+ ret = -EINVAL;
+ goto out_err;
+ }
+
/* duplicate dt blob */
buf_size = fdt_totalsize(initial_boot_params);
range_len = (__dt_root_addr_cells + __dt_root_size_cells) * sizeof(u32);
+ if (image->type == KEXEC_TYPE_CRASH)
+ buf_size += fdt_prop_len("linux,elfcorehdr", range_len)
+ + fdt_prop_len("linux,usable-memory-range",
+ range_len);
+
if (initrd_load_addr)
buf_size += fdt_prop_len("initrd-start", sizeof(u64))
+ fdt_prop_len("initrd-end", sizeof(u64));
@@ -318,6 +405,23 @@ int setup_dtb(struct kimage *image,
if (nodeoffset < 0)
goto out_err;
+ if (image->type == KEXEC_TYPE_CRASH) {
+ /* add linux,elfcorehdr */
+ ret = fdt_setprop_range(buf, nodeoffset, "linux,elfcorehdr",
+ image->arch.elf_load_addr,
+ image->arch.elf_headers_sz);
+ if (ret)
+ goto out_err;
+
+ /* add linux,usable-memory-range */
+ ret = fdt_setprop_range(buf, nodeoffset,
+ "linux,usable-memory-range",
+ crashk_res.start,
+ crashk_res.end - crashk_res.start + 1);
+ if (ret)
+ goto out_err;
+ }
+
/* add bootargs */
if (cmdline) {
ret = fdt_setprop(buf, nodeoffset, "bootargs",
@@ -452,3 +556,44 @@ int load_other_segments(struct kimage *image, unsigned long kernel_load_addr,
image->arch.dtb_buf = NULL;
return ret;
}
+
+int load_crashdump_segments(struct kimage *image)
+{
+ void *elf_addr;
+ unsigned long elf_sz;
+ struct kexec_buf kbuf;
+ int ret;
+
+ if (image->type != KEXEC_TYPE_CRASH)
+ return 0;
+
+ /* Prepare elf headers and add a segment */
+ ret = prepare_elf_headers(image, &elf_addr, &elf_sz);
+ if (ret) {
+ pr_err("Preparing elf core header failed\n");
+ return ret;
+ }
+
+ kbuf.image = image;
+ kbuf.buffer = elf_addr;
+ kbuf.bufsz = elf_sz;
+ kbuf.memsz = elf_sz;
+ kbuf.buf_align = PAGE_SIZE;
+ kbuf.buf_min = crashk_res.start;
+ kbuf.buf_max = crashk_res.end + 1;
+ kbuf.top_down = 1;
+
+ ret = kexec_add_buffer(&kbuf);
+ if (ret) {
+ vfree(elf_addr);
+ return ret;
+ }
+ image->arch.elf_headers = elf_addr;
+ image->arch.elf_headers_sz = elf_sz;
+ image->arch.elf_load_addr = kbuf.mem;
+
+ pr_debug("Loaded elf core header at 0x%lx bufsz=0x%lx memsz=0x%lx\n",
+ image->arch.elf_load_addr, elf_sz, elf_sz);
+
+ return ret;
+}
--
2.14.1
[toc] | [prev] | [standalone]
Page 3 of 3 — ← Prev page 1 2 [3]
Back to top | Article view | linux.kernel
csiph-web