From a56376080a9378a40a85cef455f7455a48d171ce Mon Sep 17 00:00:00 2001 From: Eric DeVolder Date: Wed, 27 Sep 2023 14:11:34 -0400 Subject: crashdump: exclude elfcorehdr segment from digest for hotplug To allow direct modification of the elfcorehdr by the kernel, in response to CPU and memory hot un/plug and/or online/offline events, the buffer containing the elfcorehdr must be excluded from the purgatory checksum/digest. If the elfcorehdr is not excluded from the purgatory checksum/digest, then at panic time, the checksum/digest check fails (due to the elfcorehdr having been modified), and the kdump capture kernel does not start. Signed-off-by: Eric DeVolder Signed-off-by: Simon Horman --- kexec/kexec.c | 8 ++++++++ kexec/kexec.h | 1 + 2 files changed, 9 insertions(+) diff --git a/kexec/kexec.c b/kexec/kexec.c index 02076081..fdb4c984 100644 --- a/kexec/kexec.c +++ b/kexec/kexec.c @@ -689,6 +689,14 @@ static void update_purgatory(struct kexec_info *info) if (info->segment[i].mem == (void *)info->rhdr.rel_addr) { continue; } + + /* Don't include elfcorehdr in the checksum, if hotplug + * support enabled. + */ + if (do_hotplug && (info->segment[i].mem == (void *)info->elfcorehdr)) { + continue; + } + sha256_update(&ctx, info->segment[i].buf, info->segment[i].bufsz); nullsz = info->segment[i].memsz - info->segment[i].bufsz; diff --git a/kexec/kexec.h b/kexec/kexec.h index 487f707a..1004aff1 100644 --- a/kexec/kexec.h +++ b/kexec/kexec.h @@ -170,6 +170,7 @@ struct kexec_info { int command_line_len; int skip_checks; + unsigned long elfcorehdr; }; struct arch_map_entry { -- cgit 1.2.3-korg