DAMON_SYSFS can leak memory under allocation failure, and do NULL
pointer dereference when a privileged user make wrong sequences of
control.  Fix those.

Changes from v2
(https://lore.kernel.org/20260320163559.178101-1-objecting@objecting.org)
- Wordsmith second patch commit message.
- Add NULL dereference trigger steps on the commit messages.
- Collect the valid Reviewed-by: from SJ for the second patch.
- Rebased to latest mm-new.
Changes from v1
(https://lore.kernel.org/20260319155742.186627-1-objecting@objecting.org)
- Check kdamond->contexts->nr from damon_sysfs_handle_cmd()
- Collect Reviewed-by: from SJ for the first and the third patch.

Josh Law (3):
  mm/damon/sysfs: fix param_ctx leak on damon_sysfs_new_test_ctx()
    failure
  mm/damon/sysfs: check contexts->nr before accessing contexts_arr[0]
  mm/damon/sysfs: check contexts->nr in repeat_call_fn

 mm/damon/sysfs.c | 10 +++++++++-
 1 file changed, 9 insertions(+), 1 deletion(-)


base-commit: 42bc5b563370622d688719aa248a4c861839373a
-- 
2.47.3

Forwarding sashiko.dev review status for this thread.

# review url: https://sashiko.dev/#/patchset/20260321175427.86000-1-sj@kernel.org

- [PATCH v3 1/3] mm/damon/sysfs: fix param_ctx leak on damon_sysfs_new_test_ctx() failure
  - status: Reviewed
  - review: No issues found.
- [PATCH v3 2/3] mm/damon/sysfs: check contexts->nr before accessing contexts_arr[0]
  - status: Reviewed
  - review: No issues found.
- [PATCH v3 3/3] mm/damon/sysfs: check contexts->nr in repeat_call_fn
  - status: Reviewed

# hkml [1] generated a draft of this mail.  It can be regenerated
# using below command:
#
#     hkml patch sashiko_dev --thread_status --for_forwarding \
#             20260321175427.86000-1-sj@kernel.org
#
# [1] https://github.com/sjp38/hackermail


Thanks,
SJ