Re: [PATCH 00/21] Multipath-tools: various bug fixes

[Benjamin Marzinski <bmarzins@redhat.com>]

On Wed, Dec 17, 2025 at 10:20:52PM +0100, Martin Wilck wrote:
> This series contains a number of fixes for various recent issues with
> multipath-tools. The starting point was a use-after-free issue reported on
> GitHub [1]. The actual fixes for that are 02/21 and 06/21. Because this
> Patches 3-12 generally rework the freeing of maps, trying to avoid unexpected
> freeing of paths while freeing multipath structures.
> 
> Because this changes memory handling in multipathd, I ran a set of tests to
> make sure the series doesn't open up new memory leaks. The good news is that I
> haven't found any, except some trivial ones (15/21, 16/21). But I did see one
> minor issue related to libudev [2]. After I found a warning in the libudev man
> page about the library not being thread-safe, I suspected that this might be
> causing the leak, and came up with code wrapping all libudev calls with a
> mutex (18/21, 19/21).  Unfortunately it didn't fix the observed leak, but I
> suppose it's still useful because multipathd is using libudev in a way that
> the authors of the library explicitly dismiss as unsupported.
> 
> The release of cmocka 2.0 [3] necessitated rather large-ish adaptations in our
> unit test code (20/21, 21/21).
> 
> Finally 13/21 and 17/21 are bug fixes; in particular the latter is rather nasty.
> 
> [1] https://github.com/opensvc/multipath-tools/issues/128
> [2] https://github.com/opensvc/multipath-tools/issues/130
> [3] https://github.com/opensvc/multipath-tools/issues/129
> 

For everything but 3,9,12, and 17

Reviewed-by: Benjamin Marzinski <bmarzins@redhat.com>

> Martin Wilck (21):
>   libmultipath: drop drop_multipath
>   libmultipath: don't access path members in free_pgvec()
>   multipathd: free paths in checker_finished()
>   libmultipath: don't touch mpvec in remove_map()
>   libmpathutil: constify find_slot()
>   libmultipath: don't free paths in orphan_paths()
>   libmultipath: free orphaned paths in check_removed_paths()
>   libmultipath: remove free_paths argument from free_pathgroup()
>   libmultipath: fix numeric value of free_paths in free_multipaths()
>   libmultipath: remove free_paths argument from free_pgvec()
>   libmultipath: remove free_paths argument from free_multipathvec()
>   libmultipath: free_multipath: fix FREE_PATHS case
>   multipath-tools: Fix ISO C23 errors with strchr()
>   libmultipath: simplify sysfs_get_target_nodename()
>   multipathd: join the init_unwinder dummy thread
>   kpartx: fix some memory leaks
>   libmpathutil: use union for bitfield
>   libmpathutil: add wrapper code for libudev
>   multipath-tools: use the libudev wrapper functions
>   Makefile: add functionality to determine cmocka version
>   multipath-tools tests: adaptations for cmocka 2.0
> 
>  Makefile.inc                          |   2 +-
>  create-config.mk                      |   5 +
>  kpartx/kpartx.c                       |  18 +-
>  libdmmp/Makefile                      |   2 +-
>  libdmmp/libdmmp.c                     |   2 +-
>  libmpathpersist/mpath_persist.c       |   2 +-
>  libmpathpersist/mpath_persist_int.c   |   2 +-
>  libmpathpersist/mpath_pr_ioctl.c      |   2 +-
>  libmpathpersist/mpath_updatepr.c      |   2 +-
>  libmpathutil/Makefile                 |   2 +-
>  libmpathutil/globals.c                |   2 +-
>  libmpathutil/libmpathutil.version     |  62 ++
>  libmpathutil/mt-libudev.c             | 776 ++++++++++++++++++++++++++
>  libmpathutil/mt-libudev.h             | 120 ++++
>  libmpathutil/mt-udev-wrap.h           |  90 +++
>  libmpathutil/parser.c                 |   2 +-
>  libmpathutil/util.c                   |  12 +-
>  libmpathutil/util.h                   |  43 +-
>  libmpathutil/vector.c                 |   3 +-
>  libmpathutil/vector.h                 |   2 +-
>  libmpathvalid/mpath_valid.c           |   2 +-
>  libmultipath/blacklist.c              |   2 +-
>  libmultipath/blacklist.h              |   2 +-
>  libmultipath/config.c                 |   2 +-
>  libmultipath/configure.c              |  22 +-
>  libmultipath/dict.c                   |   2 +-
>  libmultipath/discovery.c              |  36 +-
>  libmultipath/dmparser.c               |   6 +-
>  libmultipath/foreign.c                |   2 +-
>  libmultipath/foreign.h                |   2 +-
>  libmultipath/foreign/nvme.c           |   2 +-
>  libmultipath/libmultipath.version     |   2 +
>  libmultipath/pgpolicies.c             |  14 +-
>  libmultipath/print.c                  |   2 +-
>  libmultipath/prio.c                   |   2 +-
>  libmultipath/prioritizers/alua_rtpg.c |   2 +-
>  libmultipath/prioritizers/ana.c       |   2 +-
>  libmultipath/prkey.c                  |   4 +-
>  libmultipath/prkey.h                  |   2 +-
>  libmultipath/propsel.c                |   2 +-
>  libmultipath/structs.c                |  94 ++--
>  libmultipath/structs.h                |   7 +-
>  libmultipath/structs_vec.c            |  58 +-
>  libmultipath/structs_vec.h            |   4 +-
>  libmultipath/sysfs.c                  |   2 +-
>  libmultipath/uevent.c                 |   2 +-
>  libmultipath/valid.c                  |   2 +-
>  mpathpersist/main.c                   |   2 +-
>  multipath/main.c                      |  16 +-
>  multipathd/cli_handlers.c             |   2 +-
>  multipathd/fpin_handlers.c            |   2 +-
>  multipathd/init_unwinder.c            |   4 +-
>  multipathd/main.c                     |  20 +-
>  tests/Makefile                        |  22 +-
>  tests/alias.c                         |  44 +-
>  tests/blacklist.c                     |   2 +-
>  tests/cli.c                           |   8 +-
>  tests/cmocka-compat.h                 |  16 +
>  tests/devt.c                          |   6 +-
>  tests/directio.c                      |  23 +-
>  tests/dmevents.c                      |  74 +--
>  tests/features.c                      |   2 +-
>  tests/hwtable.c                       |   6 +-
>  tests/mapinfo.c                       |  82 +--
>  tests/mpathvalid.c                    |  18 +-
>  tests/parser.c                        |   2 +-
>  tests/pgpolicy.c                      |   4 +-
>  tests/strbuf.c                        | 130 ++---
>  tests/sysfs.c                         |  76 +--
>  tests/test-lib.c                      |  90 +--
>  tests/test-log.c                      |  10 +-
>  tests/uevent.c                        |   2 +-
>  tests/unaligned.c                     |   8 +-
>  tests/util.c                          | 116 ++--
>  tests/valid.c                         |  30 +-
>  tests/vpd.c                           |  12 +-
>  76 files changed, 1680 insertions(+), 581 deletions(-)
>  create mode 100644 libmpathutil/mt-libudev.c
>  create mode 100644 libmpathutil/mt-libudev.h
>  create mode 100644 libmpathutil/mt-udev-wrap.h
>  create mode 100644 tests/cmocka-compat.h
> 
> -- 
> 2.52.0