From b7c67206594a56be2407ae4da54a114c90609e53 Mon Sep 17 00:00:00 2001 From: Kees Cook Date: Fri, 22 Sep 2023 10:53:28 -0700 Subject: [PATCH] mm/memcg: annotate struct mem_cgroup_threshold_ary with __counted_by Prepare for the coming implementation by GCC and Clang of the __counted_by attribute. Flexible array members annotated with __counted_by can have their accesses bounds-checked at run-time checking via CONFIG_UBSAN_BOUNDS (for array indexing) and CONFIG_FORTIFY_SOURCE (for strcpy/memcpy-family functions). As found with Coccinelle[1], add __counted_by for struct mem_cgroup_threshold_ary. [1] https://github.com/kees/kernel-tools/blob/trunk/coccinelle/examples/counted_by.cocci Link: https://lkml.kernel.org/r/20230922175327.work.985-kees@kernel.org Signed-off-by: Kees Cook Acked-by: Shakeel Butt Acked-by: Roman Gushchin Reviewed-by: Gustavo A. R. Silva Acked-by: Michal Hocko Cc: Johannes Weiner Cc: "Matthew Wilcox (Oracle)" Signed-off-by: Andrew Morton --- include/linux/memcontrol.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/include/linux/memcontrol.h b/include/linux/memcontrol.h index 031102ac9311..c6029aeaa268 100644 --- a/include/linux/memcontrol.h +++ b/include/linux/memcontrol.h @@ -143,7 +143,7 @@ struct mem_cgroup_threshold_ary { /* Size of entries[] */ unsigned int size; /* Array of thresholds */ - struct mem_cgroup_threshold entries[]; + struct mem_cgroup_threshold entries[] __counted_by(size); }; struct mem_cgroup_thresholds {