The patch titled Subject: mm/damon/sysfs-schemes: handle tried region directory allocation failure has been added to the -mm mm-hotfixes-unstable branch. Its filename is mm-damon-sysfs-schemes-handle-tried-region-directory-allocation-failure.patch

This patch will shortly appear at https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches...

This patch will later appear in the mm-hotfixes-unstable branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

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------------------------------------------------------ From: SeongJae Park sj@kernel.org Subject: mm/damon/sysfs-schemes: handle tried region directory allocation failure Date: Mon, 6 Nov 2023 23:34:08 +0000

DAMON sysfs interface's before_damos_apply callback (damon_sysfs_before_damos_apply()), which creates the DAMOS tried regions for each DAMOS action applied region, is not handling the allocation failure for the sysfs directory data. As a result, NULL pointer derefeence is possible. Fix it by handling the case.

Link: https://lkml.kernel.org/r/20231106233408.51159-4-sj@kernel.org Fixes: f1d13cacabe1 ("mm/damon/sysfs: implement DAMOS tried regions update command") Signed-off-by: SeongJae Park sj@kernel.org Cc: stable@vger.kernel.org [6.2+] Signed-off-by: Andrew Morton akpm@linux-foundation.org ---

mm/damon/sysfs-schemes.c | 2 ++ 1 file changed, 2 insertions(+)

--- a/mm/damon/sysfs-schemes.c~mm-damon-sysfs-schemes-handle-tried-region-directory-allocation-failure +++ a/mm/damon/sysfs-schemes.c @@ -1826,6 +1826,8 @@ static int damon_sysfs_before_damos_appl return 0;

region = damon_sysfs_scheme_region_alloc(r); + if (!region) + return 0; list_add_tail(&region->list, &sysfs_regions->regions_list); sysfs_regions->nr_regions++; if (kobject_init_and_add(&region->kobj, _

Patches currently in -mm which might be from sj@kernel.org are

mm-damon-sysfs-check-error-from-damon_sysfs_update_target.patch mm-damon-sysfs-schemes-handle-tried-regions-sysfs-directory-allocation-failure.patch mm-damon-sysfs-schemes-handle-tried-region-directory-allocation-failure.patch