linux-stable/mm/kfence
Muchun Song 5229bb42fb mm: kfence: fix using kfence_metadata without initialization in show_object()
commit 1c86a188e0 upstream.

The variable kfence_metadata is initialized in kfence_init_pool(), then,
it is not initialized if kfence is disabled after booting.  In this case,
kfence_metadata will be used (e.g.  ->lock and ->state fields) without
initialization when reading /sys/kernel/debug/kfence/objects.  There will
be a warning if you enable CONFIG_DEBUG_SPINLOCK.  Fix it by creating
debugfs files when necessary.

Link: https://lkml.kernel.org/r/20230315034441.44321-1-songmuchun@bytedance.com
Fixes: 0ce20dd840 ("mm: add Kernel Electric-Fence infrastructure")
Signed-off-by: Muchun Song <songmuchun@bytedance.com>
Tested-by: Marco Elver <elver@google.com>
Reviewed-by: Marco Elver <elver@google.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Jann Horn <jannh@google.com>
Cc: SeongJae Park <sjpark@amazon.de>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-03-30 12:48:01 +02:00
..
Makefile kfence: avoid passing -g for test 2023-03-30 12:47:58 +02:00
core.c mm: kfence: fix using kfence_metadata without initialization in show_object() 2023-03-30 12:48:01 +02:00
kfence.h mm: kfence: fix objcgs vector allocation 2022-05-01 17:22:28 +02:00
kfence_test.c Merge branch 'akpm' (patches from Andrew) 2021-09-08 12:55:35 -07:00
report.c panic: Consolidate open-coded panic_on_warn checks 2023-02-01 08:27:22 +01:00