net: filter: cleanup invocation of internal BPF

Kernel API for classic BPF socket filters is:

sk_unattached_filter_create() - validate classic BPF, convert, JIT
SK_RUN_FILTER() - run it
sk_unattached_filter_destroy() - destroy socket filter

Cleanup internal BPF kernel API as following:

sk_filter_select_runtime() - final step of internal BPF creation.
  Try to JIT internal BPF program, if JIT is not available select interpreter
SK_RUN_FILTER() - run it
sk_filter_free() - free internal BPF program

Disallow direct calls to BPF interpreter. Execution of the BPF program should
be done with SK_RUN_FILTER() macro.

Example of internal BPF create, run, destroy:

  struct sk_filter *fp;

  fp = kzalloc(sk_filter_size(prog_len), GFP_KERNEL);
  memcpy(fp->insni, prog, prog_len * sizeof(fp->insni[0]));
  fp->len = prog_len;

  sk_filter_select_runtime(fp);

  SK_RUN_FILTER(fp, ctx);

  sk_filter_free(fp);

Sockets, seccomp, testsuite, tracing are using different ways to populate
sk_filter, so first steps of program creation are not common.

Signed-off-by: Alexei Starovoitov <ast@plumgrid.com>
Acked-by: Daniel Borkmann <dborkman@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 2 insertions, 2 deletions

diff --git a/lib/test_bpf.c b/lib/test_bpf.c
index 3603ebc..e160934 100644
--- a/lib/test_bpf.c
+++ b/lib/test_bpf.c
@@ -1489,7 +1489,7 @@ static __init int test_bpf(void)
 			memcpy(fp_ext->insns, tests[i].insns_int,
 			       fprog.len * 8);
 			fp->len = fprog.len;
-			fp->bpf_func = sk_run_filter_int_skb;
+			sk_filter_select_runtime(fp);
 		} else {
 			err = sk_unattached_filter_create(&fp, &fprog);
 			if (tests[i].data_type == EXPECTED_FAIL) {
@@ -1516,7 +1516,7 @@ static __init int test_bpf(void)
 		if (tests[i].data_type != SKB_INT)
 			sk_unattached_filter_destroy(fp);
 		else
-			kfree(fp);
+			sk_filter_free(fp);
 
 		if (err) {
 			pr_cont("FAIL %d\n", err);