From ae636ae2bbfd9279f5681dbf320d1da817e52b68 Mon Sep 17 00:00:00 2001 From: SeongJae Park Date: Mon, 6 Nov 2023 23:34:08 +0000 Subject: mm/damon/sysfs-schemes: handle tried region directory allocation failure 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 Cc: [6.2+] Signed-off-by: Andrew Morton --- mm/damon/sysfs-schemes.c | 2 ++ 1 file changed, 2 insertions(+) (limited to 'mm') diff --git a/mm/damon/sysfs-schemes.c b/mm/damon/sysfs-schemes.c index 7413cb35c5a9..be667236b8e6 100644 --- a/mm/damon/sysfs-schemes.c +++ b/mm/damon/sysfs-schemes.c @@ -1826,6 +1826,8 @@ static int damon_sysfs_before_damos_apply(struct damon_ctx *ctx, return 0; region = damon_sysfs_scheme_region_alloc(r); + if (!region) + return 0; list_add_tail(®ion->list, &sysfs_regions->regions_list); sysfs_regions->nr_regions++; if (kobject_init_and_add(®ion->kobj, -- cgit