diff options
Diffstat (limited to 'kernel/kexec_file.c')
| -rw-r--r-- | kernel/kexec_file.c | 673 |
1 files changed, 315 insertions, 358 deletions
diff --git a/kernel/kexec_file.c b/kernel/kexec_file.c index f1d0e00a3971..eb62a9794242 100644 --- a/kernel/kexec_file.c +++ b/kernel/kexec_file.c @@ -1,12 +1,10 @@ +// SPDX-License-Identifier: GPL-2.0-only /* * kexec: kexec_file_load system call * * Copyright (C) 2014 Red Hat Inc. * Authors: * Vivek Goyal <vgoyal@redhat.com> - * - * This source code is licensed under the GNU General Public License, - * Version 2. See the file COPYING for more details. */ #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt @@ -21,17 +19,45 @@ #include <linux/list.h> #include <linux/fs.h> #include <linux/ima.h> -#include <crypto/hash.h> -#include <crypto/sha.h> +#include <crypto/sha2.h> #include <linux/elf.h> #include <linux/elfcore.h> #include <linux/kernel.h> +#include <linux/kernel_read_file.h> #include <linux/syscalls.h> #include <linux/vmalloc.h> +#include <linux/dma-map-ops.h> #include "kexec_internal.h" +#ifdef CONFIG_KEXEC_SIG +static bool sig_enforce = IS_ENABLED(CONFIG_KEXEC_SIG_FORCE); + +void set_kexec_sig_enforced(void) +{ + sig_enforce = true; +} +#endif + +#ifdef CONFIG_IMA_KEXEC +static bool check_ima_segment_index(struct kimage *image, int i) +{ + if (image->is_ima_segment_index_set && i == image->ima_segment_index) + return true; + else + return false; +} +#else +static bool check_ima_segment_index(struct kimage *image, int i) +{ + return false; +} +#endif + static int kexec_calculate_store_digests(struct kimage *image); +/* Maximum size in bytes for kernel/initrd files. */ +#define KEXEC_FILE_SIZE_MAX min_t(s64, 4LL << 30, SSIZE_MAX) + /* * Currently this is the only default function that is exported as some * architectures need it to do additional handlings. @@ -54,13 +80,6 @@ int kexec_image_probe_default(struct kimage *image, void *buf, return ret; } -/* Architectures can provide this probe function */ -int __weak arch_kexec_kernel_image_probe(struct kimage *image, void *buf, - unsigned long buf_len) -{ - return kexec_image_probe_default(image, buf, buf_len); -} - static void *kexec_image_load_default(struct kimage *image) { if (!image->fops || !image->fops->load) @@ -72,11 +91,6 @@ static void *kexec_image_load_default(struct kimage *image) image->cmdline_buf_len); } -void * __weak arch_kexec_kernel_image_load(struct kimage *image) -{ - return kexec_image_load_default(image); -} - int kexec_image_post_load_cleanup_default(struct kimage *image) { if (!image->fops || !image->fops->cleanup) @@ -85,64 +99,6 @@ int kexec_image_post_load_cleanup_default(struct kimage *image) return image->fops->cleanup(image->image_loader_data); } -int __weak arch_kimage_file_post_load_cleanup(struct kimage *image) -{ - return kexec_image_post_load_cleanup_default(image); -} - -#ifdef CONFIG_KEXEC_VERIFY_SIG -static int kexec_image_verify_sig_default(struct kimage *image, void *buf, - unsigned long buf_len) -{ - if (!image->fops || !image->fops->verify_sig) { - pr_debug("kernel loader does not support signature verification.\n"); - return -EKEYREJECTED; - } - - return image->fops->verify_sig(buf, buf_len); -} - -int __weak arch_kexec_kernel_verify_sig(struct kimage *image, void *buf, - unsigned long buf_len) -{ - return kexec_image_verify_sig_default(image, buf, buf_len); -} -#endif - -/* - * arch_kexec_apply_relocations_add - apply relocations of type RELA - * @pi: Purgatory to be relocated. - * @section: Section relocations applying to. - * @relsec: Section containing RELAs. - * @symtab: Corresponding symtab. - * - * Return: 0 on success, negative errno on error. - */ -int __weak -arch_kexec_apply_relocations_add(struct purgatory_info *pi, Elf_Shdr *section, - const Elf_Shdr *relsec, const Elf_Shdr *symtab) -{ - pr_err("RELA relocation unsupported.\n"); - return -ENOEXEC; -} - -/* - * arch_kexec_apply_relocations - apply relocations of type REL - * @pi: Purgatory to be relocated. - * @section: Section relocations applying to. - * @relsec: Section containing RELs. - * @symtab: Corresponding symtab. - * - * Return: 0 on success, negative errno on error. - */ -int __weak -arch_kexec_apply_relocations(struct purgatory_info *pi, Elf_Shdr *section, - const Elf_Shdr *relsec, const Elf_Shdr *symtab) -{ - pr_err("REL relocation unsupported.\n"); - return -ENOEXEC; -} - /* * Free up memory used by kernel, initrd, and command line. This is temporary * memory allocation which is not needed any more after these buffers have @@ -167,6 +123,11 @@ void kimage_file_post_load_cleanup(struct kimage *image) vfree(pi->sechdrs); pi->sechdrs = NULL; +#ifdef CONFIG_IMA_KEXEC + vfree(image->ima_buffer); + image->ima_buffer = NULL; +#endif /* CONFIG_IMA_KEXEC */ + /* See if architecture has anything to cleanup post load */ arch_kimage_file_post_load_cleanup(image); @@ -177,6 +138,76 @@ void kimage_file_post_load_cleanup(struct kimage *image) */ kfree(image->image_loader_data); image->image_loader_data = NULL; + + kexec_file_dbg_print = false; +} + +#ifdef CONFIG_KEXEC_SIG +#ifdef CONFIG_SIGNED_PE_FILE_VERIFICATION +int kexec_kernel_verify_pe_sig(const char *kernel, unsigned long kernel_len) +{ + int ret; + + ret = verify_pefile_signature(kernel, kernel_len, + VERIFY_USE_SECONDARY_KEYRING, + VERIFYING_KEXEC_PE_SIGNATURE); + if (ret == -ENOKEY && IS_ENABLED(CONFIG_INTEGRITY_PLATFORM_KEYRING)) { + ret = verify_pefile_signature(kernel, kernel_len, + VERIFY_USE_PLATFORM_KEYRING, + VERIFYING_KEXEC_PE_SIGNATURE); + } + return ret; +} +#endif + +static int kexec_image_verify_sig(struct kimage *image, void *buf, + unsigned long buf_len) +{ + if (!image->fops || !image->fops->verify_sig) { + pr_debug("kernel loader does not support signature verification.\n"); + return -EKEYREJECTED; + } + + return image->fops->verify_sig(buf, buf_len); +} + +static int +kimage_validate_signature(struct kimage *image) +{ + int ret; + + ret = kexec_image_verify_sig(image, image->kernel_buf, + image->kernel_buf_len); + if (ret) { + + if (sig_enforce) { + pr_notice("Enforced kernel signature verification failed (%d).\n", ret); + return ret; + } + + /* + * If IMA is guaranteed to appraise a signature on the kexec + * image, permit it even if the kernel is otherwise locked + * down. + */ + if (!ima_appraise_signature(READING_KEXEC_IMAGE) && + security_locked_down(LOCKDOWN_KEXEC)) + return -EPERM; + + pr_debug("kernel signature verification failed (%d).\n", ret); + } + + return 0; +} +#endif + +static int kexec_post_load(struct kimage *image, unsigned long flags) +{ +#ifdef CONFIG_IMA_KEXEC + if (!(flags & KEXEC_FILE_ON_CRASH)) + ima_kexec_post_load(image); +#endif + return machine_kexec_post_load(image); } /* @@ -188,18 +219,17 @@ kimage_file_prepare_segments(struct kimage *image, int kernel_fd, int initrd_fd, const char __user *cmdline_ptr, unsigned long cmdline_len, unsigned flags) { - int ret = 0; + ssize_t ret; void *ldata; - loff_t size; - ret = kernel_read_file_from_fd(kernel_fd, &image->kernel_buf, - &size, INT_MAX, READING_KEXEC_IMAGE); - if (ret) + ret = kernel_read_file_from_fd(kernel_fd, 0, &image->kernel_buf, + KEXEC_FILE_SIZE_MAX, NULL, + READING_KEXEC_IMAGE); + if (ret < 0) return ret; - image->kernel_buf_len = size; - - /* IMA needs to pass the measurement list to the next kernel. */ - ima_add_kexec_buffer(image); + image->kernel_buf_len = ret; + kexec_dprintk("kernel: %p kernel_size: %#lx\n", + image->kernel_buf, image->kernel_buf_len); /* Call arch image probe handlers */ ret = arch_kexec_kernel_image_probe(image, image->kernel_buf, @@ -207,25 +237,26 @@ kimage_file_prepare_segments(struct kimage *image, int kernel_fd, int initrd_fd, if (ret) goto out; -#ifdef CONFIG_KEXEC_VERIFY_SIG - ret = arch_kexec_kernel_verify_sig(image, image->kernel_buf, - image->kernel_buf_len); - if (ret) { - pr_debug("kernel signature verification failed.\n"); +#ifdef CONFIG_KEXEC_SIG + ret = kimage_validate_signature(image); + + if (ret) goto out; - } - pr_debug("kernel signature verification successful.\n"); #endif /* It is possible that there no initramfs is being loaded */ if (!(flags & KEXEC_FILE_NO_INITRAMFS)) { - ret = kernel_read_file_from_fd(initrd_fd, &image->initrd_buf, - &size, INT_MAX, + ret = kernel_read_file_from_fd(initrd_fd, 0, &image->initrd_buf, + KEXEC_FILE_SIZE_MAX, NULL, READING_KEXEC_INITRAMFS); - if (ret) + if (ret < 0) goto out; - image->initrd_buf_len = size; + image->initrd_buf_len = ret; + ret = 0; } + image->no_cma = !!(flags & KEXEC_FILE_NO_CMA); + image->force_dtb = flags & KEXEC_FILE_FORCE_DTB; + if (cmdline_len) { image->cmdline_buf = memdup_user(cmdline_ptr, cmdline_len); if (IS_ERR(image->cmdline_buf)) { @@ -241,10 +272,21 @@ kimage_file_prepare_segments(struct kimage *image, int kernel_fd, int initrd_fd, ret = -EINVAL; goto out; } + + ima_kexec_cmdline(kernel_fd, image->cmdline_buf, + image->cmdline_buf_len - 1); } - /* Call arch image load handlers */ - ldata = arch_kexec_kernel_image_load(image); + /* IMA needs to pass the measurement list to the next kernel. */ + ima_add_kexec_buffer(image); + + /* If KHO is active, add its images to the list */ + ret = kho_fill_kimage(image); + if (ret) + goto out; + + /* Call image load handler */ + ldata = kexec_image_load_default(image); if (IS_ERR(ldata)) { ret = PTR_ERR(ldata); @@ -272,13 +314,16 @@ kimage_file_alloc_init(struct kimage **rimage, int kernel_fd, if (!image) return -ENOMEM; + kexec_file_dbg_print = !!(flags & KEXEC_FILE_DEBUG); image->file_mode = 1; +#ifdef CONFIG_CRASH_DUMP if (kexec_on_panic) { /* Enable special crash kernel control page alloc policy. */ image->control_page = crashk_res.start; image->type = KEXEC_TYPE_CRASH; } +#endif ret = kimage_file_prepare_segments(image, kernel_fd, initrd_fd, cmdline_ptr, cmdline_len, flags); @@ -320,11 +365,13 @@ SYSCALL_DEFINE5(kexec_file_load, int, kernel_fd, int, initrd_fd, unsigned long, cmdline_len, const char __user *, cmdline_ptr, unsigned long, flags) { - int ret = 0, i; + int image_type = (flags & KEXEC_FILE_ON_CRASH) ? + KEXEC_TYPE_CRASH : KEXEC_TYPE_DEFAULT; struct kimage **dest_image, *image; + int ret = 0, i; /* We only trust the superuser with rebooting the system. */ - if (!capable(CAP_SYS_BOOT) || kexec_load_disabled) + if (!kexec_load_permitted(image_type)) return -EPERM; /* Make sure we have a legal set of flags */ @@ -333,15 +380,17 @@ SYSCALL_DEFINE5(kexec_file_load, int, kernel_fd, int, initrd_fd, image = NULL; - if (!mutex_trylock(&kexec_mutex)) + if (!kexec_trylock()) return -EBUSY; - dest_image = &kexec_image; - if (flags & KEXEC_FILE_ON_CRASH) { +#ifdef CONFIG_CRASH_DUMP + if (image_type == KEXEC_TYPE_CRASH) { dest_image = &kexec_crash_image; if (kexec_crash_image) arch_kexec_unprotect_crashkres(); - } + } else +#endif + dest_image = &kexec_image; if (flags & KEXEC_FILE_UNLOAD) goto exchange; @@ -359,6 +408,11 @@ SYSCALL_DEFINE5(kexec_file_load, int, kernel_fd, int, initrd_fd, if (ret) goto out; +#ifdef CONFIG_CRASH_HOTPLUG + if ((flags & KEXEC_FILE_ON_CRASH) && arch_crash_hotplug_support(image, flags)) + image->hotplug_support = 1; +#endif + ret = machine_kexec_prepare(image); if (ret) goto out; @@ -375,21 +429,28 @@ SYSCALL_DEFINE5(kexec_file_load, int, kernel_fd, int, initrd_fd, if (ret) goto out; + kexec_dprintk("nr_segments = %lu\n", image->nr_segments); for (i = 0; i < image->nr_segments; i++) { struct kexec_segment *ksegment; ksegment = &image->segment[i]; - pr_debug("Loading segment %d: buf=0x%p bufsz=0x%zx mem=0x%lx memsz=0x%zx\n", - i, ksegment->buf, ksegment->bufsz, ksegment->mem, - ksegment->memsz); + kexec_dprintk("segment[%d]: buf=0x%p bufsz=0x%zx mem=0x%lx memsz=0x%zx\n", + i, ksegment->buf, ksegment->bufsz, ksegment->mem, + ksegment->memsz); - ret = kimage_load_segment(image, &image->segment[i]); + ret = kimage_load_segment(image, i); if (ret) goto out; } kimage_terminate(image); + ret = kexec_post_load(image, flags); + if (ret) + goto out; + + kexec_dprintk("kexec_file_load: type:%u, start:0x%lx head:0x%lx flags:0x%lx\n", + image->type, image->start, image->head, flags); /* * Free up any temporary buffers allocated which are not needed * after image has been loaded @@ -398,10 +459,12 @@ SYSCALL_DEFINE5(kexec_file_load, int, kernel_fd, int, initrd_fd, exchange: image = xchg(dest_image, image); out: +#ifdef CONFIG_CRASH_DUMP if ((flags & KEXEC_FILE_ON_CRASH) && kexec_crash_image) arch_kexec_protect_crashkres(); +#endif - mutex_unlock(&kexec_mutex); + kexec_unlock(); kimage_free(image); return ret; } @@ -413,11 +476,12 @@ static int locate_mem_hole_top_down(unsigned long start, unsigned long end, unsigned long temp_start, temp_end; temp_end = min(end, kbuf->buf_max); - temp_start = temp_end - kbuf->memsz; + temp_start = temp_end - kbuf->memsz + 1; + kexec_random_range_start(temp_start, temp_end, kbuf, &temp_start); do { /* align down start */ - temp_start = temp_start & (~(kbuf->buf_align - 1)); + temp_start = ALIGN_DOWN(temp_start, kbuf->buf_align); if (temp_start < start || temp_start < kbuf->buf_min) return 0; @@ -433,6 +497,12 @@ static int locate_mem_hole_top_down(unsigned long start, unsigned long end, continue; } + /* Make sure this does not conflict with exclude range */ + if (arch_check_excluded_range(image, temp_start, temp_end)) { + temp_start = temp_start - PAGE_SIZE; + continue; + } + /* We found a suitable memory range */ break; } while (1); @@ -452,6 +522,8 @@ static int locate_mem_hole_bottom_up(unsigned long start, unsigned long end, temp_start = max(start, kbuf->buf_min); + kexec_random_range_start(temp_start, end, kbuf, &temp_start); + do { temp_start = ALIGN(temp_start, kbuf->buf_align); temp_end = temp_start + kbuf->memsz - 1; @@ -467,6 +539,12 @@ static int locate_mem_hole_bottom_up(unsigned long start, unsigned long end, continue; } + /* Make sure this does not conflict with exclude range */ + if (arch_check_excluded_range(image, temp_start, temp_end)) { + temp_start = temp_start + PAGE_SIZE; + continue; + } + /* We found a suitable memory range */ break; } while (1); @@ -485,6 +563,11 @@ static int locate_mem_hole_callback(struct resource *res, void *arg) unsigned long sz = end - start + 1; /* Returning 0 will take to next memory range */ + + /* Don't use memory that will be detected and handled by a driver. */ + if (res->flags & IORESOURCE_SYSRAM_DRIVER_MANAGED) + return 0; + if (sz < kbuf->memsz) return 0; @@ -500,13 +583,7 @@ static int locate_mem_hole_callback(struct resource *res, void *arg) return locate_mem_hole_bottom_up(start, end, kbuf); } -#ifdef CONFIG_ARCH_DISCARD_MEMBLOCK -static int kexec_walk_memblock(struct kexec_buf *kbuf, - int (*func)(struct resource *, void *)) -{ - return 0; -} -#else +#ifdef CONFIG_ARCH_KEEP_MEMBLOCK static int kexec_walk_memblock(struct kexec_buf *kbuf, int (*func)(struct resource *, void *)) { @@ -515,9 +592,16 @@ static int kexec_walk_memblock(struct kexec_buf *kbuf, phys_addr_t mstart, mend; struct resource res = { }; +#ifdef CONFIG_CRASH_DUMP if (kbuf->image->type == KEXEC_TYPE_CRASH) return func(&crashk_res, kbuf); +#endif + /* + * Using MEMBLOCK_NONE will properly skip MEMBLOCK_DRIVER_MANAGED. See + * IORESOURCE_SYSRAM_DRIVER_MANAGED handling in + * locate_mem_hole_callback(). + */ if (kbuf->top_down) { for_each_free_mem_range_reverse(i, NUMA_NO_NODE, MEMBLOCK_NONE, &mstart, &mend, NULL) { @@ -550,6 +634,12 @@ static int kexec_walk_memblock(struct kexec_buf *kbuf, return ret; } +#else +static int kexec_walk_memblock(struct kexec_buf *kbuf, + int (*func)(struct resource *, void *)) +{ + return 0; +} #endif /** @@ -564,15 +654,56 @@ static int kexec_walk_memblock(struct kexec_buf *kbuf, static int kexec_walk_resources(struct kexec_buf *kbuf, int (*func)(struct resource *, void *)) { +#ifdef CONFIG_CRASH_DUMP if (kbuf->image->type == KEXEC_TYPE_CRASH) return walk_iomem_res_desc(crashk_res.desc, IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY, crashk_res.start, crashk_res.end, kbuf, func); +#endif + if (kbuf->top_down) + return walk_system_ram_res_rev(0, ULONG_MAX, kbuf, func); else return walk_system_ram_res(0, ULONG_MAX, kbuf, func); } +static int kexec_alloc_contig(struct kexec_buf *kbuf) +{ + size_t nr_pages = kbuf->memsz >> PAGE_SHIFT; + unsigned long mem; + struct page *p; + + /* User space disabled CMA allocations, bail out. */ + if (kbuf->image->no_cma) + return -EPERM; + + /* Skip CMA logic for crash kernel */ + if (kbuf->image->type == KEXEC_TYPE_CRASH) + return -EPERM; + + p = dma_alloc_from_contiguous(NULL, nr_pages, get_order(kbuf->buf_align), true); + if (!p) + return -ENOMEM; + + pr_debug("allocated %zu DMA pages at 0x%lx", nr_pages, page_to_boot_pfn(p)); + + mem = page_to_boot_pfn(p) << PAGE_SHIFT; + + if (kimage_is_destination_range(kbuf->image, mem, mem + kbuf->memsz)) { + /* Our region is already in use by a statically defined one. Bail out. */ + pr_debug("CMA overlaps existing mem: 0x%lx+0x%lx\n", mem, kbuf->memsz); + dma_release_from_contiguous(NULL, p, nr_pages); + return -EBUSY; + } + + kbuf->mem = page_to_boot_pfn(p) << PAGE_SHIFT; + kbuf->cma = p; + + arch_kexec_post_alloc_pages(page_address(p), (int)nr_pages, 0); + + return 0; +} + /** * kexec_locate_mem_hole - find free memory for the purgatory or the next kernel * @kbuf: Parameters for the memory search. @@ -589,7 +720,22 @@ int kexec_locate_mem_hole(struct kexec_buf *kbuf) if (kbuf->mem != KEXEC_BUF_MEM_UNKNOWN) return 0; - if (IS_ENABLED(CONFIG_ARCH_DISCARD_MEMBLOCK)) + /* + * If KHO is active, only use KHO scratch memory. All other memory + * could potentially be handed over. + */ + ret = kho_locate_mem_hole(kbuf, locate_mem_hole_callback); + if (ret <= 0) + return ret; + + /* + * Try to find a free physically contiguous block of memory first. With that, we + * can avoid any copying at kexec time. + */ + if (!kexec_alloc_contig(kbuf)) + return 0; + + if (!IS_ENABLED(CONFIG_ARCH_KEEP_MEMBLOCK)) ret = kexec_walk_resources(kbuf, locate_mem_hole_callback); else ret = kexec_walk_memblock(kbuf, locate_mem_hole_callback); @@ -601,7 +747,7 @@ int kexec_locate_mem_hole(struct kexec_buf *kbuf) * kexec_add_buffer - place a buffer in a kexec segment * @kbuf: Buffer contents and memory parameters. * - * This function assumes that kexec_mutex is held. + * This function assumes that kexec_lock is held. * On successful return, @kbuf->mem will have the physical address of * the buffer in memory. * @@ -609,7 +755,6 @@ int kexec_locate_mem_hole(struct kexec_buf *kbuf) */ int kexec_add_buffer(struct kexec_buf *kbuf) { - struct kexec_segment *ksegment; int ret; @@ -635,9 +780,10 @@ int kexec_add_buffer(struct kexec_buf *kbuf) /* Ensure minimum alignment needed for segments. */ kbuf->memsz = ALIGN(kbuf->memsz, PAGE_SIZE); kbuf->buf_align = max(kbuf->buf_align, PAGE_SIZE); + kbuf->cma = NULL; /* Walk the RAM ranges and allocate a suitable range for the buffer */ - ret = kexec_locate_mem_hole(kbuf); + ret = arch_kexec_locate_mem_hole(kbuf); if (ret) return ret; @@ -647,6 +793,7 @@ int kexec_add_buffer(struct kexec_buf *kbuf) ksegment->bufsz = kbuf->bufsz; ksegment->mem = kbuf->mem; ksegment->memsz = kbuf->memsz; + kbuf->image->segment_cma[kbuf->image->nr_segments] = kbuf->cma; kbuf->image->nr_segments++; return 0; } @@ -654,55 +801,36 @@ int kexec_add_buffer(struct kexec_buf *kbuf) /* Calculate and store the digest of segments */ static int kexec_calculate_store_digests(struct kimage *image) { - struct crypto_shash *tfm; - struct shash_desc *desc; + struct sha256_ctx sctx; int ret = 0, i, j, zero_buf_sz, sha_region_sz; - size_t desc_size, nullsz; - char *digest; + size_t nullsz; + u8 digest[SHA256_DIGEST_SIZE]; void *zero_buf; struct kexec_sha_region *sha_regions; struct purgatory_info *pi = &image->purgatory_info; - if (!IS_ENABLED(CONFIG_ARCH_HAS_KEXEC_PURGATORY)) + if (!IS_ENABLED(CONFIG_ARCH_SUPPORTS_KEXEC_PURGATORY)) return 0; zero_buf = __va(page_to_pfn(ZERO_PAGE(0)) << PAGE_SHIFT); zero_buf_sz = PAGE_SIZE; - tfm = crypto_alloc_shash("sha256", 0, 0); - if (IS_ERR(tfm)) { - ret = PTR_ERR(tfm); - goto out; - } - - desc_size = crypto_shash_descsize(tfm) + sizeof(*desc); - desc = kzalloc(desc_size, GFP_KERNEL); - if (!desc) { - ret = -ENOMEM; - goto out_free_tfm; - } - sha_region_sz = KEXEC_SEGMENT_MAX * sizeof(struct kexec_sha_region); sha_regions = vzalloc(sha_region_sz); if (!sha_regions) - goto out_free_desc; + return -ENOMEM; - desc->tfm = tfm; - desc->flags = 0; - - ret = crypto_shash_init(desc); - if (ret < 0) - goto out_free_sha_regions; - - digest = kzalloc(SHA256_DIGEST_SIZE, GFP_KERNEL); - if (!digest) { - ret = -ENOMEM; - goto out_free_sha_regions; - } + sha256_init(&sctx); for (j = i = 0; i < image->nr_segments; i++) { struct kexec_segment *ksegment; +#ifdef CONFIG_CRASH_HOTPLUG + /* Exclude elfcorehdr segment to allow future changes via hotplug */ + if (i == image->elfcorehdr_index) + continue; +#endif + ksegment = &image->segment[i]; /* * Skip purgatory as it will be modified once we put digest @@ -711,10 +839,14 @@ static int kexec_calculate_store_digests(struct kimage *image) if (ksegment->kbuf == pi->purgatory_buf) continue; - ret = crypto_shash_update(desc, ksegment->kbuf, - ksegment->bufsz); - if (ret) - break; + /* + * Skip the segment if ima_segment_index is set and matches + * the current index + */ + if (check_ima_segment_index(image, i)) + continue; + + sha256_update(&sctx, ksegment->kbuf, ksegment->bufsz); /* * Assume rest of the buffer is filled with zero and @@ -726,48 +858,30 @@ static int kexec_calculate_store_digests(struct kimage *image) if (bytes > zero_buf_sz) bytes = zero_buf_sz; - ret = crypto_shash_update(desc, zero_buf, bytes); - if (ret) - break; + sha256_update(&sctx, zero_buf, bytes); nullsz -= bytes; } - if (ret) - break; - sha_regions[j].start = ksegment->mem; sha_regions[j].len = ksegment->memsz; j++; } - if (!ret) { - ret = crypto_shash_final(desc, digest); - if (ret) - goto out_free_digest; - ret = kexec_purgatory_get_set_symbol(image, "purgatory_sha_regions", - sha_regions, sha_region_sz, 0); - if (ret) - goto out_free_digest; + sha256_final(&sctx, digest); - ret = kexec_purgatory_get_set_symbol(image, "purgatory_sha256_digest", - digest, SHA256_DIGEST_SIZE, 0); - if (ret) - goto out_free_digest; - } + ret = kexec_purgatory_get_set_symbol(image, "purgatory_sha_regions", + sha_regions, sha_region_sz, 0); + if (ret) + goto out_free_sha_regions; -out_free_digest: - kfree(digest); + ret = kexec_purgatory_get_set_symbol(image, "purgatory_sha256_digest", + digest, SHA256_DIGEST_SIZE, 0); out_free_sha_regions: vfree(sha_regions); -out_free_desc: - kfree(desc); -out_free_tfm: - kfree(tfm); -out: return ret; } -#ifdef CONFIG_ARCH_HAS_KEXEC_PURGATORY +#ifdef CONFIG_ARCH_SUPPORTS_KEXEC_PURGATORY /* * kexec_purgatory_setup_kbuf - prepare buffer to load purgatory. * @pi: Purgatory to be loaded. @@ -844,6 +958,7 @@ static int kexec_purgatory_setup_sechdrs(struct purgatory_info *pi, { unsigned long bss_addr; unsigned long offset; + size_t sechdrs_size; Elf_Shdr *sechdrs; int i; @@ -851,11 +966,11 @@ static int kexec_purgatory_setup_sechdrs(struct purgatory_info *pi, * The section headers in kexec_purgatory are read-only. In order to * have them modifiable make a temporary copy. */ - sechdrs = vzalloc(array_size(sizeof(Elf_Shdr), pi->ehdr->e_shnum)); + sechdrs_size = array_size(sizeof(Elf_Shdr), pi->ehdr->e_shnum); + sechdrs = vzalloc(sechdrs_size); if (!sechdrs) return -ENOMEM; - memcpy(sechdrs, (void *)pi->ehdr + pi->ehdr->e_shoff, - pi->ehdr->e_shnum * sizeof(Elf_Shdr)); + memcpy(sechdrs, (void *)pi->ehdr + pi->ehdr->e_shoff, sechdrs_size); pi->sechdrs = sechdrs; offset = 0; @@ -878,10 +993,22 @@ static int kexec_purgatory_setup_sechdrs(struct purgatory_info *pi, } offset = ALIGN(offset, align); + + /* + * Check if the segment contains the entry point, if so, + * calculate the value of image->start based on it. + * If the compiler has produced more than one .text section + * (Eg: .text.hot), they are generally after the main .text + * section, and they shall not be used to calculate + * image->start. So do not re-calculate image->start if it + * is not set to the initial value, and warn the user so they + * have a chance to fix their purgatory's linker script. + */ if (sechdrs[i].sh_flags & SHF_EXECINSTR && pi->ehdr->e_entry >= sechdrs[i].sh_addr && pi->ehdr->e_entry < (sechdrs[i].sh_addr - + sechdrs[i].sh_size)) { + + sechdrs[i].sh_size) && + !WARN_ON(kbuf->image->start != pi->ehdr->e_entry)) { kbuf->image->start -= sechdrs[i].sh_addr; kbuf->image->start += kbuf->mem + offset; } @@ -1114,174 +1241,4 @@ int kexec_purgatory_get_set_symbol(struct kimage *image, const char *name, return 0; } -#endif /* CONFIG_ARCH_HAS_KEXEC_PURGATORY */ - -int crash_exclude_mem_range(struct crash_mem *mem, - unsigned long long mstart, unsigned long long mend) -{ - int i, j; - unsigned long long start, end; - 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 == mem->max_nr_ranges - 1) - return -ENOMEM; - - /* Location where new range should go */ - j = i + 1; - if (j < mem->nr_ranges) { - /* Move over all ranges one slot towards the end */ - for (i = mem->nr_ranges - 1; i >= j; i--) - mem->ranges[i + 1] = mem->ranges[i]; - } - - mem->ranges[j].start = temp_range.start; - mem->ranges[j].end = temp_range.end; - mem->nr_ranges++; - return 0; -} - -int crash_prepare_elf64_headers(struct crash_mem *mem, int kernel_map, - void **addr, unsigned long *sz) -{ - Elf64_Ehdr *ehdr; - Elf64_Phdr *phdr; - unsigned long nr_cpus = num_possible_cpus(), nr_phdr, elf_sz; - unsigned char *buf; - unsigned int cpu, i; - unsigned long long notes_addr; - unsigned long mstart, mend; - - /* extra phdr for vmcoreinfo elf note */ - nr_phdr = nr_cpus + 1; - nr_phdr += mem->nr_ranges; - - /* - * kexec-tools creates an extra PT_LOAD phdr for kernel text mapping - * area (for example, ffffffff80000000 - ffffffffa0000000 on x86_64). - * I think this is required by tools like gdb. So same physical - * memory will be mapped in two elf headers. One will contain kernel - * text virtual addresses and other will have __va(physical) addresses. - */ - - nr_phdr++; - elf_sz = sizeof(Elf64_Ehdr) + nr_phdr * sizeof(Elf64_Phdr); - elf_sz = ALIGN(elf_sz, ELF_CORE_HEADER_ALIGN); - - buf = vzalloc(elf_sz); - if (!buf) - return -ENOMEM; - - ehdr = (Elf64_Ehdr *)buf; - phdr = (Elf64_Phdr *)(ehdr + 1); - memcpy(ehdr->e_ident, ELFMAG, SELFMAG); - ehdr->e_ident[EI_CLASS] = ELFCLASS64; - ehdr->e_ident[EI_DATA] = ELFDATA2LSB; - ehdr->e_ident[EI_VERSION] = EV_CURRENT; - ehdr->e_ident[EI_OSABI] = ELF_OSABI; - memset(ehdr->e_ident + EI_PAD, 0, EI_NIDENT - EI_PAD); - ehdr->e_type = ET_CORE; - ehdr->e_machine = ELF_ARCH; - ehdr->e_version = EV_CURRENT; - ehdr->e_phoff = sizeof(Elf64_Ehdr); - ehdr->e_ehsize = sizeof(Elf64_Ehdr); - ehdr->e_phentsize = sizeof(Elf64_Phdr); - - /* Prepare one phdr of type PT_NOTE for each present cpu */ - for_each_present_cpu(cpu) { - phdr->p_type = PT_NOTE; - notes_addr = per_cpu_ptr_to_phys(per_cpu_ptr(crash_notes, cpu)); - phdr->p_offset = phdr->p_paddr = notes_addr; - phdr->p_filesz = phdr->p_memsz = sizeof(note_buf_t); - (ehdr->e_phnum)++; - phdr++; - } - - /* Prepare one PT_NOTE header for vmcoreinfo */ - phdr->p_type = PT_NOTE; - phdr->p_offset = phdr->p_paddr = paddr_vmcoreinfo_note(); - phdr->p_filesz = phdr->p_memsz = VMCOREINFO_NOTE_SIZE; - (ehdr->e_phnum)++; - phdr++; - - /* Prepare PT_LOAD type program header for kernel text region */ - if (kernel_map) { - 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++; - phdr++; - } - - /* Go through all the ranges in mem->ranges[] and prepare phdr */ - for (i = 0; i < mem->nr_ranges; i++) { - mstart = mem->ranges[i].start; - mend = mem->ranges[i].end; - - phdr->p_type = PT_LOAD; - phdr->p_flags = PF_R|PF_W|PF_X; - phdr->p_offset = mstart; - - phdr->p_paddr = mstart; - phdr->p_vaddr = (unsigned long long) __va(mstart); - phdr->p_filesz = phdr->p_memsz = mend - mstart + 1; - phdr->p_align = 0; - ehdr->e_phnum++; - phdr++; - 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); - } - - *addr = buf; - *sz = elf_sz; - return 0; -} +#endif /* CONFIG_ARCH_SUPPORTS_KEXEC_PURGATORY */ |