linux-kernel - [PATCH bpf-next v3 05/17] bpf: mark struct oom_control's memcg field as TRUSTED_OR

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20260127024421.494929-6-roman.gushchin@linux.dev>
Date: Mon, 26 Jan 2026 18:44:08 -0800
From: Roman Gushchin <roman.gushchin@...ux.dev>
To: bpf@...r.kernel.org
Cc: Michal Hocko <mhocko@...e.com>,
	Alexei Starovoitov <ast@...nel.org>,
	Matt Bobrowski <mattbobrowski@...gle.com>,
	Shakeel Butt <shakeel.butt@...ux.dev>,
	JP Kobryn <inwardvessel@...il.com>,
	linux-kernel@...r.kernel.org,
	linux-mm@...ck.org,
	Suren Baghdasaryan <surenb@...gle.com>,
	Johannes Weiner <hannes@...xchg.org>,
	Andrew Morton <akpm@...ux-foundation.org>,
	Roman Gushchin <roman.gushchin@...ux.dev>,
	Kumar Kartikeya Dwivedi <memxor@...il.com>
Subject: [PATCH bpf-next v3 05/17] bpf: mark struct oom_control's memcg field as TRUSTED_OR_NULL

Struct oom_control is used to describe the OOM context.
It's memcg field defines the scope of OOM: it's NULL for global
OOMs and a valid memcg pointer for memcg-scoped OOMs.
Teach bpf verifier to recognize it as trusted or NULL pointer.
It will provide the bpf OOM handler a trusted memcg pointer,
which for example is required for iterating the memcg's subtree.

Signed-off-by: Roman Gushchin <roman.gushchin@...ux.dev>
Acked-by: Kumar Kartikeya Dwivedi <memxor@...il.com>
---
 kernel/bpf/verifier.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c
index c2f2650db9fd..cca36edb460d 100644
--- a/kernel/bpf/verifier.c
+++ b/kernel/bpf/verifier.c
@@ -7242,6 +7242,10 @@ BTF_TYPE_SAFE_TRUSTED_OR_NULL(struct vm_area_struct) {
 	struct file *vm_file;
 };
 
+BTF_TYPE_SAFE_TRUSTED_OR_NULL(struct oom_control) {
+	struct mem_cgroup *memcg;
+};
+
 static bool type_is_rcu(struct bpf_verifier_env *env,
 			struct bpf_reg_state *reg,
 			const char *field_name, u32 btf_id)
@@ -7284,6 +7288,7 @@ static bool type_is_trusted_or_null(struct bpf_verifier_env *env,
 	BTF_TYPE_EMIT(BTF_TYPE_SAFE_TRUSTED_OR_NULL(struct socket));
 	BTF_TYPE_EMIT(BTF_TYPE_SAFE_TRUSTED_OR_NULL(struct dentry));
 	BTF_TYPE_EMIT(BTF_TYPE_SAFE_TRUSTED_OR_NULL(struct vm_area_struct));
+	BTF_TYPE_EMIT(BTF_TYPE_SAFE_TRUSTED_OR_NULL(struct oom_control));
 
 	return btf_nested_type_is_trusted(&env->log, reg, field_name, btf_id,
 					  "__safe_trusted_or_null");
-- 
2.52.0