This patch adds default BPF capabilities initialization for
program types.
Since this is a proof of concept, only BPF capabilities initialization
for BPF_PROG_TYPE_STRUCT_OPS is added.
BPF_PROG_TYPE_STRUCT_OPS enables only STRUCT_OPS_BASE_CAPS and
BPF_CAP_SCX_ANY by default.
Signed-off-by: Juntong Deng <juntong.deng@xxxxxxxxxxx>
---
kernel/bpf/verifier.c | 37 +++++++++++++++++++++++++++++++++++++
1 file changed, 37 insertions(+)
diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c
index 2a321a641b4a..7a69a581861f 100644
--- a/kernel/bpf/verifier.c
+++ b/kernel/bpf/verifier.c
@@ -22959,6 +22959,40 @@ static int process_fd_array(struct bpf_verifier_env *env, union bpf_attr *attr,
return 0;
}
+#define STRUCT_OPS_BASE_CAPS \
+ BPF_CAP_TEST_1, \
+ BPF_CAP_TEST_2, \
+ BPF_CAP_TEST_3
+
+static const enum bpf_capability struct_ops_caps[] = {
+ STRUCT_OPS_BASE_CAPS,
+ BPF_CAP_SCX_ANY
+};
+
+struct bpf_program_type_caps {
+ enum bpf_prog_type type;
+ u32 size;
+ const enum bpf_capability *capabilities;
+};
+
+static const struct bpf_program_type_caps bpf_default_capabilities[] = {
+ {
+ .type = BPF_PROG_TYPE_STRUCT_OPS,
+ .size = ARRAY_SIZE(struct_ops_caps),
+ .capabilities = struct_ops_caps
+ },
+};
+
+static void setup_bpf_capabilities(unsigned long *bpf_capabilities,
+ const struct bpf_program_type_caps *caps)
+{
+ int i;
+
+ bitmap_zero(bpf_capabilities, __MAX_BPF_CAP);
+ for (i = 0; i < caps->size; i++)
+ ENABLE_BPF_CAPABILITY(bpf_capabilities, caps->capabilities[i]);
+}
+
int bpf_check(struct bpf_prog **prog, union bpf_attr *attr, bpfptr_t uattr, __u32 uattr_size)
{
u64 start_time = ktime_get_ns();
@@ -22997,6 +23031,9 @@ int bpf_check(struct bpf_prog **prog, union bpf_attr *attr, bpfptr_t uattr, __u3
env->bypass_spec_v4 = bpf_bypass_spec_v4(env->prog->aux->token);
env->bpf_capable = is_priv = bpf_token_capable(env->prog->aux->token, CAP_BPF);
+ if (env->prog->type == BPF_PROG_TYPE_STRUCT_OPS)
+ setup_bpf_capabilities(env->bpf_capabilities, &bpf_default_capabilities[0]);
+
bpf_get_btf_vmlinux();
/* grab the mutex to protect few globals used by verifier */
--
2.39.5
