The patch titled Subject: mm/damon/core: handle error from 'damon_fill_regions_holes()' has been added to the -mm mm-unstable branch. Its filename is mm-damon-core-avoid-holes-in-newly-set-monitoring-target-ranges-fix.patch This patch will shortly appear at https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/mm-damon-core-avoid-holes-in-newly-set-monitoring-target-ranges-fix.patch This patch will later appear in the mm-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/core: handle error from 'damon_fill_regions_holes()' Date: Tue, 13 Sep 2022 21:54:20 +0000 Commit 91fc6af21c61 ("mm/damon/core: avoid holes in newly set monitoring target ranges") in mm-unstable tree introduces 'damon_fill_regions_holes()', which does not check failures of 'damon_new_region()' call, so NULL dereferencing is available. This commit fixes the issue by checking failure of the function and returning an error code. Link: https://lkml.kernel.org/r/20220913215420.57761-1-sj@xxxxxxxxxx Fixes: 91fc6af21c61 ("mm/damon/core: avoid holes in newly set monitoring target ranges") in mm-unstable Signed-off-by: SeongJae Park <sj@xxxxxxxxxx> Reported-by: Coverity Static Analyzer CID 1524904 Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- mm/damon/core.c | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-) --- a/mm/damon/core.c~mm-damon-core-avoid-holes-in-newly-set-monitoring-target-ranges-fix +++ a/mm/damon/core.c @@ -171,7 +171,7 @@ static bool damon_intersect(struct damon /* * Fill holes in regions with new regions. */ -static void damon_fill_regions_holes(struct damon_region *first, +static int damon_fill_regions_holes(struct damon_region *first, struct damon_region *last, struct damon_target *t) { struct damon_region *r = first; @@ -184,9 +184,12 @@ static void damon_fill_regions_holes(str next = damon_next_region(r); if (r->ar.end != next->ar.start) { newr = damon_new_region(r->ar.end, next->ar.start); + if (!newr) + return -ENOMEM; damon_insert_region(newr, r, next, t); } } + return 0; } /* @@ -205,6 +208,7 @@ int damon_set_regions(struct damon_targe { struct damon_region *r, *next; unsigned int i; + int err; /* Remove regions which are not in the new ranges */ damon_for_each_region_safe(r, next, t) { @@ -249,7 +253,9 @@ int damon_set_regions(struct damon_targe last->ar.end = ALIGN(range->end, DAMON_MIN_REGION); /* fill possible holes in the range */ - damon_fill_regions_holes(first, last, t); + err = damon_fill_regions_holes(first, last, t); + if (err) + return err; } } return 0; _ Patches currently in -mm which might be from sj@xxxxxxxxxx are mm-demotion-update-node_is_toptier-to-work-with-memory-tiers-fix.patch selftest-damon-add-a-test-for-duplicate-context-dirs-creation.patch mm-damon-core-avoid-holes-in-newly-set-monitoring-target-ranges.patch mm-damon-core-avoid-holes-in-newly-set-monitoring-target-ranges-fix.patch mm-damon-core-test-test-damon_set_regions.patch docs-admin-guide-mm-damon-rename-the-title-of-the-document.patch mm-damon-kconfig-notify-debugfs-deprecation-plan.patch docs-admin-guide-mm-damon-start-mention-the-dependency-as-sysfs-instead-of-debugfs.patch docs-admin-guide-mm-damon-usage-note-damon-debugfs-interface-deprecation-plan.patch mm-damon-paddr-make-supported-damos-actions-of-paddr-clear.patch mm-damon-paddr-deduplicate-damon_pa_mark_accesseddeactivate_pages.patch mm-damon-core-copy-struct-to-struct-instead-of-field-to-field-in-damon_new_scheme.patch mm-damon-core-factor-out-damos_quota-private-fileds-initialization.patch mm-damon-core-use-a-dedicated-struct-for-monitoring-attributes.patch mm-damon-core-reduce-parameters-for-damon_set_attrs.patch mm-damon-reclaim-use-struct-damon_attrs-for-storing-parameters-for-it.patch mm-damon-lru_sort-use-struct-damon_attrs-for-storing-parameters-for-it.patch mm-damon-implement-a-monitoring-attributes-module-parameters-generator-macro.patch mm-damon-lru_sort-use-monitoring-attributes-parameters-generaotr-macro.patch mm-damon-reclaim-use-monitoring-attributes-parameters-generator-macro.patch mm-damon-modules-common-implement-a-watermarks-module-parameters-generator-macro.patch mm-damon-lru_sort-use-watermarks-parameters-generator-macro.patch mm-damon-reclaim-use-watermarks-parameters-generator-macro.patch mm-damon-modules-common-implement-a-stats-parameters-generator-macro.patch mm-damon-reclaim-use-stat-parameters-generator.patch mm-damon-lru_sort-use-stat-generator.patch mm-damon-modules-common-implement-a-damos-quota-params-generator.patch mm-damon-modules-common-implement-damos-time-quota-params-generator.patch mm-damon-reclaim-use-the-quota-params-generator-macro.patch mm-damon-lru_sort-use-quotas-param-generator.patch mm-damon-lru_sort-deduplicate-hot-cold-schemes-generators.patch