diff options
| -rw-r--r-- | include/linux/crash_core.h | 6 | ||||
| -rw-r--r-- | kernel/crash_core.c | 50 |
2 files changed, 56 insertions, 0 deletions
diff --git a/include/linux/crash_core.h b/include/linux/crash_core.h index 525510a9f965..6594dbc34a37 100644 --- a/include/linux/crash_core.h +++ b/include/linux/crash_core.h @@ -38,6 +38,8 @@ phys_addr_t paddr_vmcoreinfo_note(void); #define VMCOREINFO_OSRELEASE(value) \ vmcoreinfo_append_str("OSRELEASE=%s\n", value) +#define VMCOREINFO_BUILD_ID(value) \ + vmcoreinfo_append_str("BUILD-ID=%s\n", value) #define VMCOREINFO_PAGESIZE(value) \ vmcoreinfo_append_str("PAGESIZE=%ld\n", value) #define VMCOREINFO_SYMBOL(name) \ @@ -64,6 +66,10 @@ extern unsigned char *vmcoreinfo_data; extern size_t vmcoreinfo_size; extern u32 *vmcoreinfo_note; +/* raw contents of kernel .notes section */ +extern const void __start_notes __weak; +extern const void __stop_notes __weak; + Elf_Word *append_elf_note(Elf_Word *buf, char *name, unsigned int type, void *data, size_t data_len); void final_note(Elf_Word *buf); diff --git a/kernel/crash_core.c b/kernel/crash_core.c index 18175687133a..106e4500fd53 100644 --- a/kernel/crash_core.c +++ b/kernel/crash_core.c @@ -11,6 +11,8 @@ #include <asm/page.h> #include <asm/sections.h> +#include <crypto/sha.h> + /* vmcoreinfo stuff */ unsigned char *vmcoreinfo_data; size_t vmcoreinfo_size; @@ -376,6 +378,53 @@ phys_addr_t __weak paddr_vmcoreinfo_note(void) } EXPORT_SYMBOL(paddr_vmcoreinfo_note); +#define NOTES_SIZE (&__stop_notes - &__start_notes) +#define BUILD_ID_MAX SHA1_DIGEST_SIZE +#define NT_GNU_BUILD_ID 3 + +struct elf_note_section { + struct elf_note n_hdr; + u8 n_data[]; +}; + +/* + * Add build ID from .notes section as generated by the GNU ld(1) + * or LLVM lld(1) --build-id option. + */ +static void add_build_id_vmcoreinfo(void) +{ + char build_id[BUILD_ID_MAX * 2 + 1]; + int n_remain = NOTES_SIZE; + + while (n_remain >= sizeof(struct elf_note)) { + const struct elf_note_section *note_sec = + &__start_notes + NOTES_SIZE - n_remain; + const u32 n_namesz = note_sec->n_hdr.n_namesz; + + if (note_sec->n_hdr.n_type == NT_GNU_BUILD_ID && + n_namesz != 0 && + !strcmp((char *)¬e_sec->n_data[0], "GNU")) { + if (note_sec->n_hdr.n_descsz <= BUILD_ID_MAX) { + const u32 n_descsz = note_sec->n_hdr.n_descsz; + const u8 *s = ¬e_sec->n_data[n_namesz]; + + s = PTR_ALIGN(s, 4); + bin2hex(build_id, s, n_descsz); + build_id[2 * n_descsz] = '\0'; + VMCOREINFO_BUILD_ID(build_id); + return; + } + pr_warn("Build ID is too large to include in vmcoreinfo: %u > %u\n", + note_sec->n_hdr.n_descsz, + BUILD_ID_MAX); + return; + } + n_remain -= sizeof(struct elf_note) + + ALIGN(note_sec->n_hdr.n_namesz, 4) + + ALIGN(note_sec->n_hdr.n_descsz, 4); + } +} + static int __init crash_save_vmcoreinfo_init(void) { vmcoreinfo_data = (unsigned char *)get_zeroed_page(GFP_KERNEL); @@ -394,6 +443,7 @@ static int __init crash_save_vmcoreinfo_init(void) } VMCOREINFO_OSRELEASE(init_uts_ns.name.release); + add_build_id_vmcoreinfo(); VMCOREINFO_PAGESIZE(PAGE_SIZE); VMCOREINFO_SYMBOL(init_uts_ns); |