The patch titled Subject: mm/damon/sysfs-schemes: handle schemes sysfs dir removal before commit_schemes_quota_goals has been added to the -mm mm-hotfixes-unstable branch. Its filename is mm-damon-sysfs-schemes-handle-schemes-sysfs-dir-removal-before-commit_schemes_quota_goals.patch This patch will shortly appear at https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/mm-damon-sysfs-schemes-handle-schemes-sysfs-dir-removal-before-commit_schemes_quota_goals.patch This patch will later appear in the mm-hotfixes-unstable branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's *** Remember to use Documentation/process/submit-checklist.rst when testing your code *** The -mm tree is included into linux-next via the mm-everything branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm and is updated there every 2-3 working days ------------------------------------------------------ From: SeongJae Park <sj@xxxxxxxxxx> Subject: mm/damon/sysfs-schemes: handle schemes sysfs dir removal before commit_schemes_quota_goals Date: Mon, 12 Feb 2024 18:36:32 -0800 'commit_schemes_quota_goals' command handler, damos_sysfs_set_quota_scores() assumes the number of schemes sysfs directory will be same to the number of schemes of the DAMON context. The assumption is wrong since users can remove schemes sysfs directories while DAMON is running. In the case, illegal memory accesses can happen. Fix it by checking the case. Link: https://lkml.kernel.org/r/20240213023633.124928-1-sj@xxxxxxxxxx Fixes: d91beaa505a0 ("mm/damon/sysfs-schemes: implement a command for scheme quota goals only commit") Signed-off-by: SeongJae Park <sj@xxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- mm/damon/sysfs-schemes.c | 4 ++++ 1 file changed, 4 insertions(+) --- a/mm/damon/sysfs-schemes.c~mm-damon-sysfs-schemes-handle-schemes-sysfs-dir-removal-before-commit_schemes_quota_goals +++ a/mm/damon/sysfs-schemes.c @@ -1905,6 +1905,10 @@ void damos_sysfs_set_quota_scores(struct damon_for_each_scheme(scheme, ctx) { struct damon_sysfs_scheme *sysfs_scheme; + /* user could have removed the scheme sysfs dir */ + if (i >= sysfs_schemes->nr) + break; + sysfs_scheme = sysfs_schemes->schemes_arr[i]; damos_sysfs_set_quota_score(sysfs_scheme->quotas->goals, &scheme->quota); _ Patches currently in -mm which might be from sj@xxxxxxxxxx are mm-damon-core-check-apply-interval-in-damon_do_apply_schemes.patch mm-damon-sysfs-schemes-handle-schemes-sysfs-dir-removal-before-commit_schemes_quota_goals.patch docs-admin-guide-mm-damon-usage-use-sysfs-interface-for-tracepoints-example.patch mm-damon-rename-config_damon_dbgfs-to-damon_dbgfs_deprecated.patch mm-damon-dbgfs-implement-deprecation-notice-file.patch mm-damon-dbgfs-make-debugfs-interface-deprecation-message-a-macro.patch docs-admin-guide-mm-damon-usage-document-deprecated-file-of-damon-debugfs-interface.patch selftets-damon-prepare-for-monitor_on-file-renaming.patch mm-damon-dbgfs-rename-monitor_on-file-to-monitor_on_deprecated.patch docs-admin-guide-mm-damon-usage-update-for-monitor_on-renaming.patch docs-translations-damon-usage-update-for-monitor_on-renaming.patch mm-damon-sysfs-handle-state-file-inputs-for-every-sampling-interval-if-possible.patch selftests-damon-_damon_sysfs-support-damos-quota.patch selftests-damon-_damon_sysfs-support-damos-stats.patch selftests-damon-_damon_sysfs-support-damos-apply-interval.patch selftests-damon-add-a-test-for-damos-quota.patch selftests-damon-add-a-test-for-damos-apply-intervals.patch selftests-damon-add-a-test-for-a-race-between-target_ids_read-and-dbgfs_before_terminate.patch selftests-damon-add-a-test-for-the-pid-leak-of-dbgfs_target_ids_write.patch selftests-damon-_chk_dependency-get-debugfs-mount-point-from-proc-mounts.patch