From 65d9a9a60fd71be964effb2e94747a6acb6e7015 Mon Sep 17 00:00:00 2001 From: "Naveen N. Rao" Date: Fri, 1 Jul 2022 13:04:04 +0530 Subject: kexec_file: drop weak attribute from functions As requested (http://lkml.kernel.org/r/87ee0q7b92.fsf@email.froward.int.ebiederm.org), this series converts weak functions in kexec to use the #ifdef approach. Quoting the 3e35142ef99fe ("kexec_file: drop weak attribute from arch_kexec_apply_relocations[_add]") changelog: : Since commit d1bcae833b32f1 ("ELF: Don't generate unused section symbols") : [1], binutils (v2.36+) started dropping section symbols that it thought : were unused. This isn't an issue in general, but with kexec_file.c, gcc : is placing kexec_arch_apply_relocations[_add] into a separate : .text.unlikely section and the section symbol ".text.unlikely" is being : dropped. Due to this, recordmcount is unable to find a non-weak symbol in : .text.unlikely to generate a relocation record against. This patch (of 2); Drop __weak attribute from functions in kexec_file.c: - arch_kexec_kernel_image_probe() - arch_kimage_file_post_load_cleanup() - arch_kexec_kernel_image_load() - arch_kexec_locate_mem_hole() - arch_kexec_kernel_verify_sig() arch_kexec_kernel_image_load() calls into kexec_image_load_default(), so drop the static attribute for the latter. arch_kexec_kernel_verify_sig() is not overridden by any architecture, so drop the __weak attribute. Link: https://lkml.kernel.org/r/cover.1656659357.git.naveen.n.rao@linux.vnet.ibm.com Link: https://lkml.kernel.org/r/2cd7ca1fe4d6bb6ca38e3283c717878388ed6788.1656659357.git.naveen.n.rao@linux.vnet.ibm.com Signed-off-by: Naveen N. Rao Suggested-by: Eric Biederman Signed-off-by: Andrew Morton Signed-off-by: Mimi Zohar --- include/linux/kexec.h | 44 ++++++++++++++++++++++++++++++++++++++------ 1 file changed, 38 insertions(+), 6 deletions(-) (limited to 'include/linux') diff --git a/include/linux/kexec.h b/include/linux/kexec.h index 475683cd67f1..6958c6b471f4 100644 --- a/include/linux/kexec.h +++ b/include/linux/kexec.h @@ -188,21 +188,53 @@ int kexec_purgatory_get_set_symbol(struct kimage *image, const char *name, void *buf, unsigned int size, bool get_value); void *kexec_purgatory_get_symbol_addr(struct kimage *image, const char *name); +void *kexec_image_load_default(struct kimage *image); + +#ifndef arch_kexec_kernel_image_probe +static inline int +arch_kexec_kernel_image_probe(struct kimage *image, void *buf, unsigned long buf_len) +{ + return kexec_image_probe_default(image, buf, buf_len); +} +#endif + +#ifndef arch_kimage_file_post_load_cleanup +static inline int arch_kimage_file_post_load_cleanup(struct kimage *image) +{ + return kexec_image_post_load_cleanup_default(image); +} +#endif + +#ifndef arch_kexec_kernel_image_load +static inline void *arch_kexec_kernel_image_load(struct kimage *image) +{ + return kexec_image_load_default(image); +} +#endif -/* Architectures may override the below functions */ -int arch_kexec_kernel_image_probe(struct kimage *image, void *buf, - unsigned long buf_len); -void *arch_kexec_kernel_image_load(struct kimage *image); -int arch_kimage_file_post_load_cleanup(struct kimage *image); #ifdef CONFIG_KEXEC_SIG int arch_kexec_kernel_verify_sig(struct kimage *image, void *buf, unsigned long buf_len); #endif -int arch_kexec_locate_mem_hole(struct kexec_buf *kbuf); extern int kexec_add_buffer(struct kexec_buf *kbuf); int kexec_locate_mem_hole(struct kexec_buf *kbuf); +#ifndef arch_kexec_locate_mem_hole +/** + * 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. + */ +static inline int arch_kexec_locate_mem_hole(struct kexec_buf *kbuf) +{ + return kexec_locate_mem_hole(kbuf); +} +#endif + /* Alignment required for elf header segment */ #define ELF_CORE_HEADER_ALIGN 4096 -- cgit From 0738eceb6201691534df07e0928d0a6168a35787 Mon Sep 17 00:00:00 2001 From: "Naveen N. Rao" Date: Fri, 1 Jul 2022 13:04:05 +0530 Subject: kexec: drop weak attribute from functions Drop __weak attribute from functions in kexec_core.c: - machine_kexec_post_load() - arch_kexec_protect_crashkres() - arch_kexec_unprotect_crashkres() - crash_free_reserved_phys_range() Link: https://lkml.kernel.org/r/c0f6219e03cb399d166d518ab505095218a902dd.1656659357.git.naveen.n.rao@linux.vnet.ibm.com Signed-off-by: Naveen N. Rao Suggested-by: Eric Biederman Signed-off-by: Andrew Morton Signed-off-by: Mimi Zohar --- include/linux/kexec.h | 32 ++++++++++++++++++++++++++++---- 1 file changed, 28 insertions(+), 4 deletions(-) (limited to 'include/linux') diff --git a/include/linux/kexec.h b/include/linux/kexec.h index 6958c6b471f4..8107606ad1e8 100644 --- a/include/linux/kexec.h +++ b/include/linux/kexec.h @@ -390,7 +390,10 @@ extern void machine_kexec_cleanup(struct kimage *image); extern int kernel_kexec(void); extern struct page *kimage_alloc_control_pages(struct kimage *image, unsigned int order); -int machine_kexec_post_load(struct kimage *image); + +#ifndef machine_kexec_post_load +static inline int machine_kexec_post_load(struct kimage *image) { return 0; } +#endif extern void __crash_kexec(struct pt_regs *); extern void crash_kexec(struct pt_regs *); @@ -423,10 +426,21 @@ extern bool kexec_in_progress; int crash_shrink_memory(unsigned long new_size); size_t crash_get_memory_size(void); -void crash_free_reserved_phys_range(unsigned long begin, unsigned long end); -void arch_kexec_protect_crashkres(void); -void arch_kexec_unprotect_crashkres(void); +#ifndef arch_kexec_protect_crashkres +/* + * Protection mechanism for crashkernel reserved memory after + * the kdump kernel is loaded. + * + * Provide an empty default implementation here -- architecture + * code may override this + */ +static inline void arch_kexec_protect_crashkres(void) { } +#endif + +#ifndef arch_kexec_unprotect_crashkres +static inline void arch_kexec_unprotect_crashkres(void) { } +#endif #ifndef page_to_boot_pfn static inline unsigned long page_to_boot_pfn(struct page *page) @@ -456,6 +470,16 @@ static inline phys_addr_t boot_phys_to_phys(unsigned long boot_phys) } #endif +#ifndef crash_free_reserved_phys_range +static inline void crash_free_reserved_phys_range(unsigned long begin, unsigned long end) +{ + unsigned long addr; + + for (addr = begin; addr < end; addr += PAGE_SIZE) + free_reserved_page(boot_pfn_to_page(addr >> PAGE_SHIFT)); +} +#endif + static inline unsigned long virt_to_boot_phys(void *addr) { return phys_to_boot_phys(__pa((unsigned long)addr)); -- cgit From 689a71493bd2f31c024f8c0395f85a1fd4b2138e Mon Sep 17 00:00:00 2001 From: Coiby Xu Date: Thu, 14 Jul 2022 21:40:24 +0800 Subject: kexec: clean up arch_kexec_kernel_verify_sig Before commit 105e10e2cf1c ("kexec_file: drop weak attribute from functions"), there was already no arch-specific implementation of arch_kexec_kernel_verify_sig. With weak attribute dropped by that commit, arch_kexec_kernel_verify_sig is completely useless. So clean it up. Note later patches are dependent on this patch so it should be backported to the stable tree as well. Cc: stable@vger.kernel.org Suggested-by: Eric W. Biederman Reviewed-by: Michal Suchanek Acked-by: Baoquan He Signed-off-by: Coiby Xu [zohar@linux.ibm.com: reworded patch description "Note"] Link: https://lore.kernel.org/linux-integrity/20220714134027.394370-1-coxu@redhat.com/ Signed-off-by: Mimi Zohar --- include/linux/kexec.h | 5 ----- 1 file changed, 5 deletions(-) (limited to 'include/linux') diff --git a/include/linux/kexec.h b/include/linux/kexec.h index 8107606ad1e8..7f710fb3712b 100644 --- a/include/linux/kexec.h +++ b/include/linux/kexec.h @@ -212,11 +212,6 @@ static inline void *arch_kexec_kernel_image_load(struct kimage *image) } #endif -#ifdef CONFIG_KEXEC_SIG -int arch_kexec_kernel_verify_sig(struct kimage *image, void *buf, - unsigned long buf_len); -#endif - extern int kexec_add_buffer(struct kexec_buf *kbuf); int kexec_locate_mem_hole(struct kexec_buf *kbuf); -- cgit From c903dae8941deb55043ee46ded29e84e97cd84bb Mon Sep 17 00:00:00 2001 From: Coiby Xu Date: Thu, 14 Jul 2022 21:40:25 +0800 Subject: kexec, KEYS: make the code in bzImage64_verify_sig generic commit 278311e417be ("kexec, KEYS: Make use of platform keyring for signature verify") adds platform keyring support on x86 kexec but not arm64. The code in bzImage64_verify_sig uses the keys on the .builtin_trusted_keys, .machine, if configured and enabled, .secondary_trusted_keys, also if configured, and .platform keyrings to verify the signed kernel image as PE file. Cc: kexec@lists.infradead.org Cc: keyrings@vger.kernel.org Cc: linux-security-module@vger.kernel.org Reviewed-by: Michal Suchanek Signed-off-by: Coiby Xu Signed-off-by: Mimi Zohar --- include/linux/kexec.h | 7 +++++++ 1 file changed, 7 insertions(+) (limited to 'include/linux') diff --git a/include/linux/kexec.h b/include/linux/kexec.h index 7f710fb3712b..13e6c4b58f07 100644 --- a/include/linux/kexec.h +++ b/include/linux/kexec.h @@ -19,6 +19,7 @@ #include #include +#include /* Location of a reserved region to hold the crash kernel. */ @@ -212,6 +213,12 @@ static inline void *arch_kexec_kernel_image_load(struct kimage *image) } #endif +#ifdef CONFIG_KEXEC_SIG +#ifdef CONFIG_SIGNED_PE_FILE_VERIFICATION +int kexec_kernel_verify_pe_sig(const char *kernel, unsigned long kernel_len); +#endif +#endif + extern int kexec_add_buffer(struct kexec_buf *kbuf); int kexec_locate_mem_hole(struct kexec_buf *kbuf); -- cgit