diff options
| author | Tao Chen <chen.dylane@gmail.com> | 2024-09-10 22:41:10 +0800 |
|---|---|---|
| committer | Andrii Nakryiko <andrii@kernel.org> | 2024-09-11 13:22:37 -0700 |
| commit | 1d244784be6b01162b732a5a7d637dfc024c3203 (patch) | |
| tree | a37a02f5d5392573121f9257917ea21e5b6f2b91 | |
| parent | 300a90b2cb5d442879e6398920c49aebbd5c8e40 (diff) | |
bpf: Check percpu map value size first
Percpu map is often used, but the map value size limit often ignored,
like issue: https://github.com/iovisor/bcc/issues/2519. Actually,
percpu map value size is bound by PCPU_MIN_UNIT_SIZE, so we
can check the value size whether it exceeds PCPU_MIN_UNIT_SIZE first,
like percpu map of local_storage. Maybe the error message seems clearer
compared with "cannot allocate memory".
Signed-off-by: Jinke Han <jinkehan@didiglobal.com>
Signed-off-by: Tao Chen <chen.dylane@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20240910144111.1464912-2-chen.dylane@gmail.com
| -rw-r--r-- | kernel/bpf/arraymap.c | 3 | ||||
| -rw-r--r-- | kernel/bpf/hashtab.c | 3 |
2 files changed, 6 insertions, 0 deletions
diff --git a/kernel/bpf/arraymap.c b/kernel/bpf/arraymap.c index a43e62e2a8bb..79660e3fca4c 100644 --- a/kernel/bpf/arraymap.c +++ b/kernel/bpf/arraymap.c @@ -73,6 +73,9 @@ int array_map_alloc_check(union bpf_attr *attr) /* avoid overflow on round_up(map->value_size) */ if (attr->value_size > INT_MAX) return -E2BIG; + /* percpu map value size is bound by PCPU_MIN_UNIT_SIZE */ + if (percpu && round_up(attr->value_size, 8) > PCPU_MIN_UNIT_SIZE) + return -E2BIG; return 0; } diff --git a/kernel/bpf/hashtab.c b/kernel/bpf/hashtab.c index 45c7195b65ba..b14b87463ee0 100644 --- a/kernel/bpf/hashtab.c +++ b/kernel/bpf/hashtab.c @@ -462,6 +462,9 @@ static int htab_map_alloc_check(union bpf_attr *attr) * kmalloc-able later in htab_map_update_elem() */ return -E2BIG; + /* percpu map value size is bound by PCPU_MIN_UNIT_SIZE */ + if (percpu && round_up(attr->value_size, 8) > PCPU_MIN_UNIT_SIZE) + return -E2BIG; return 0; } |