The incoming patches need to handle UEFI format image, which is in PE format. Hence introducing some routines here.
Signed-off-by: Pingfan Liu <[email protected]> Cc: Baoquan He <[email protected]> Cc: Dave Young <[email protected]> Cc: Andrew Morton <[email protected]> Cc: Philipp Rudo <[email protected]> To: [email protected] --- kernel/Makefile | 1 + kernel/kexec_internal.h | 3 ++ kernel/kexec_uefi_app.c | 81 +++++++++++++++++++++++++++++++++++++++++ 3 files changed, 85 insertions(+) create mode 100644 kernel/kexec_uefi_app.c diff --git a/kernel/Makefile b/kernel/Makefile index e83669841b8cc..f9e85c4a0622b 100644 --- a/kernel/Makefile +++ b/kernel/Makefile @@ -83,6 +83,7 @@ obj-$(CONFIG_CRASH_DUMP_KUNIT_TEST) += crash_core_test.o obj-$(CONFIG_KEXEC) += kexec.o obj-$(CONFIG_KEXEC_FILE) += kexec_file.o obj-$(CONFIG_KEXEC_ELF) += kexec_elf.o +obj-$(CONFIG_KEXEC_BPF) += kexec_uefi_app.o obj-$(CONFIG_BACKTRACE_SELF_TEST) += backtracetest.o obj-$(CONFIG_COMPAT) += compat.o obj-$(CONFIG_CGROUPS) += cgroup/ diff --git a/kernel/kexec_internal.h b/kernel/kexec_internal.h index 228bb88c018bc..8e5e5c1237732 100644 --- a/kernel/kexec_internal.h +++ b/kernel/kexec_internal.h @@ -36,6 +36,9 @@ static inline void kexec_unlock(void) void kimage_file_post_load_cleanup(struct kimage *image); extern char kexec_purgatory[]; extern size_t kexec_purgatory_size; +extern bool pe_has_bpf_section(const char *file_buf, unsigned long pe_sz); +extern int pe_get_section(const char *file_buf, const char *sect_name, + char **sect_start, unsigned long *sect_sz); #else /* CONFIG_KEXEC_FILE */ static inline void kimage_file_post_load_cleanup(struct kimage *image) { } #endif /* CONFIG_KEXEC_FILE */ diff --git a/kernel/kexec_uefi_app.c b/kernel/kexec_uefi_app.c new file mode 100644 index 0000000000000..dbe6d76d47ffa --- /dev/null +++ b/kernel/kexec_uefi_app.c @@ -0,0 +1,81 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * UEFI appilication file helpers + * + * Copyright (C) 2025, 2026 Red Hat, Inc + */ + +#include <linux/err.h> +#include <linux/errno.h> +#include <linux/list.h> +#include <linux/kernel.h> +#include <linux/pe.h> +#include <linux/string.h> +#include "kexec_internal.h" + +/* + * The UEFI Terse Executable (TE) image has MZ header. + */ +static bool is_valid_pe(const char *kernel_buf, unsigned long kernel_len) +{ + struct mz_hdr *mz; + struct pe_hdr *pe; + + if (!kernel_buf) + return false; + mz = (struct mz_hdr *)kernel_buf; + if (mz->magic != IMAGE_DOS_SIGNATURE) + return false; + pe = (struct pe_hdr *)(kernel_buf + mz->peaddr); + if (pe->magic != IMAGE_NT_SIGNATURE) + return false; + if (pe->opt_hdr_size == 0) { + pr_err("optional header is missing\n"); + return false; + } + return true; +} + +bool pe_has_bpf_section(const char *file_buf, unsigned long pe_sz) +{ + char *sect_start = NULL; + unsigned long sect_sz = 0; + int ret; + + if (!is_valid_pe(file_buf, pe_sz)) + return false; + ret = pe_get_section(file_buf, ".bpf", §_start, §_sz); + if (ret < 0) + return false; + return true; +} + +int pe_get_section(const char *file_buf, const char *sect_name, + char **sect_start, unsigned long *sect_sz) +{ + struct pe_hdr *pe_hdr; + struct pe32plus_opt_hdr *opt_hdr; + struct section_header *sect_hdr; + int section_nr, i; + struct mz_hdr *mz = (struct mz_hdr *)file_buf; + + *sect_start = NULL; + *sect_sz = 0; + pe_hdr = (struct pe_hdr *)(file_buf + mz->peaddr); + section_nr = pe_hdr->sections; + opt_hdr = (struct pe32plus_opt_hdr *)(file_buf + mz->peaddr + + sizeof(struct pe_hdr)); + sect_hdr = (struct section_header *)((char *)opt_hdr + + pe_hdr->opt_hdr_size); + + for (i = 0; i < section_nr; i++) { + if (strcmp(sect_hdr->name, sect_name) == 0) { + *sect_start = (char *)file_buf + sect_hdr->data_addr; + *sect_sz = sect_hdr->raw_data_size; + return 0; + } + sect_hdr++; + } + + return -1; +} -- 2.49.0
