bpf: Disable unsupported operations for map with dynptr key

Both batched map operation and dumping the map content through bpffs for maps with dynptr keys are not supported, so disable these operations for now. Signed-off-by: Hou Tao <[email protected]>
kernel-patches · Jan 25, 2025 · c3ef957 · c3ef957
1 parent fe35030
commit c3ef957
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Showing 2 changed files with 6 additions and 1 deletion.
diff --git a/include/linux/bpf.h b/include/linux/bpf.h
@@ -635,7 +635,8 @@ static inline bool bpf_map_offload_neutral(const struct bpf_map *map)
 static inline bool bpf_map_support_seq_show(const struct bpf_map *map)
 {
 	return (map->btf_value_type_id || map->btf_vmlinux_value_type_id) &&
-		map->ops->map_seq_show_elem;
+		map->ops->map_seq_show_elem &&
+		!bpf_map_has_dynptr_key(map);
 }
 
 int map_check_no_btf(const struct bpf_map *map,

diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c
@@ -5542,6 +5542,10 @@ static int bpf_map_do_batch(const union bpf_attr *attr,
 		err = -EPERM;
 		goto err_put;
 	}
+	if (bpf_map_has_dynptr_key(map)) {
+		err = -EOPNOTSUPP;
+		goto err_put;
+	}
 
 	if (cmd == BPF_MAP_LOOKUP_BATCH)
 		BPF_DO_BATCH(map->ops->map_lookup_batch, map, attr, uattr);