[PATCH v2 0/9] Bug fixes and enhancements for kdump LUKS support

[Coiby Xu <coiby.xu@gmail.com>]

Hi all,

This patch set brings some stability fixes and improvements to the
recently introduced CONFIG_CRASH_DM_CRYPT feature [1][2] (which is to
support LUKS-encrypted device dump target),
  1. resolve dumping failure when there are >=5 dm-crypt keys
  2. address several memory management issues
  3. fix race conditions like configfs writing happens concurrently with
     kexec_file_load syscall
  4. improve configfs handling
  5. update documentation 


v2
 - A different way to address potential double and UAF issues
 - Address several issues [3] scrutinized by Sourabh based on
   Sashiko's review feedback [4] on v1 patch
 - Other improvements like logging fix and doc updates

[1] http://lists.infradead.org/pipermail/kexec/2025-February/031850.html
[2] https://lore.kernel.org/all/20260225060347.718905-1-coxu@redhat.com/
[3] https://lore.kernel.org/all/972b9a73-d066-4a38-8a4b-fe7d1ba2944b@linux.ibm.com/
[4] https://sashiko.dev/#/patchset/20260403100126.1468200-1-coxu%40redhat.com

Coiby Xu (9):
  crash_dump: Release reference to a keyring at correct time
  crash_dump: Fix potential double free and UAF of keys_header
  crash_dump: Disallow writing to dm-crypt configfs during
    kexec_file_load syscall
  crash_dump: Read the number of dm-crypt keys from reserved memory
  crash_dump: Free temporary dm-crypt keys_header buffer in kdump kernel
  crash_dump: Only use kexec_dprintk during the kexec_file_load syscall
  crash_dump: Improve readability of config_keys_restore_store
  crash_dump: Disallow configfs/crash_dm_crypt_key/reuse if
    CONFIG_CRASH_HOTPLUG enabled
  Documentation: kdump: Add arm64 and ppc64le to encrypted dump target
    support list

 Documentation/admin-guide/kdump/kdump.rst |  13 ++-
 include/linux/kexec.h                     |   6 +
 kernel/crash_dump_dm_crypt.c              | 131 ++++++++++++++++------
 kernel/kexec_file.c                       |   2 +
 4 files changed, 111 insertions(+), 41 deletions(-)


base-commit: 08d0d3466664000ba0670e0ef0d447f23459e0d4
-- 
2.54.0