Merge tag 'for-netdev' of https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next

Daniel Borkmann says:

====================
pull-request: bpf-next 2023-03-06

We've added 85 non-merge commits during the last 13 day(s) which contain
a total of 131 files changed, 7102 insertions(+), 1792 deletions(-).

The main changes are:

1) Add skb and XDP typed dynptrs which allow BPF programs for more
   ergonomic and less brittle iteration through data and variable-sized
   accesses, from Joanne Koong.

2) Bigger batch of BPF verifier improvements to prepare for upcoming BPF
   open-coded iterators allowing for less restrictive looping capabilities,
   from Andrii Nakryiko.

3) Rework RCU enforcement in the verifier, add kptr_rcu and enforce BPF
   programs to NULL-check before passing such pointers into kfunc,
   from Alexei Starovoitov.

4) Add support for kptrs in percpu hashmaps, percpu LRU hashmaps and in
   local storage maps, from Kumar Kartikeya Dwivedi.

5) Add BPF verifier support for ST instructions in convert_ctx_access()
   which will help new -mcpu=v4 clang flag to start emitting them,
   from Eduard Zingerman.

6) Make uprobe attachment Android APK aware by supporting attachment
   to functions inside ELF objects contained in APKs via function names,
   from Daniel Müller.

7) Add a new flag BPF_F_TIMER_ABS flag for bpf_timer_start() helper
   to start the timer with absolute expiration value instead of relative
   one, from Tero Kristo.

8) Add a new kfunc bpf_cgroup_from_id() to look up cgroups via id,
   from Tejun Heo.

9) Extend libbpf to support users manually attaching kprobes/uprobes
   in the legacy/perf/link mode, from Menglong Dong.

10) Implement workarounds in the mips BPF JIT for DADDI/R4000,
   from Jiaxun Yang.

11) Enable mixing bpf2bpf and tailcalls for the loongarch BPF JIT,
    from Hengqi Chen.

12) Extend BPF instruction set doc with describing the encoding of BPF
    instructions in terms of how bytes are stored under big/little endian,
    from Jose E. Marchesi.

13) Follow-up to enable kfunc support for riscv BPF JIT, from Pu Lehui.

14) Fix bpf_xdp_query() backwards compatibility on old kernels,
    from Yonghong Song.

15) Fix BPF selftest cross compilation with CLANG_CROSS_FLAGS,
    from Florent Revest.

16) Improve bpf_cpumask_ma to only allocate one bpf_mem_cache,
    from Hou Tao.

17) Fix BPF verifier's check_subprogs to not unnecessarily mark
    a subprogram with has_tail_call, from Ilya Leoshkevich.

18) Fix arm syscall regs spec in libbpf's bpf_tracing.h, from Puranjay Mohan.

* tag 'for-netdev' of https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (85 commits)
  selftests/bpf: Add test for legacy/perf kprobe/uprobe attach mode
  selftests/bpf: Split test_attach_probe into multi subtests
  libbpf: Add support to set kprobe/uprobe attach mode
  tools/resolve_btfids: Add /libsubcmd to .gitignore
  bpf: add support for fixed-size memory pointer returns for kfuncs
  bpf: generalize dynptr_get_spi to be usable for iters
  bpf: mark PTR_TO_MEM as non-null register type
  bpf: move kfunc_call_arg_meta higher in the file
  bpf: ensure that r0 is marked scratched after any function call
  bpf: fix visit_insn()'s detection of BPF_FUNC_timer_set_callback helper
  bpf: clean up visit_insn()'s instruction processing
  selftests/bpf: adjust log_fixup's buffer size for proper truncation
  bpf: honor env->test_state_freq flag in is_state_visited()
  selftests/bpf: enhance align selftest's expected log matching
  bpf: improve regsafe() checks for PTR_TO_{MEM,BUF,TP_BUFFER}
  bpf: improve stack slot state printing
  selftests/bpf: Disassembler tests for verifier.c:convert_ctx_access()
  selftests/bpf: test if pointer type is tracked for BPF_ST_MEM
  bpf: allow ctx writes using BPF_ST_MEM instruction
  bpf: Use separate RCU callbacks for freeing selem
  ...
====================

Link: https://lore.kernel.org/r/20230307004346.27578-1-daniel@iogearbox.net
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

1 files changed, 113 insertions, 23 deletions

diff --git a/tools/testing/selftests/bpf/prog_tests/map_kptr.c b/tools/testing/selftests/bpf/prog_tests/map_kptr.c
index 3533a4ecad01..8743df599567 100644
--- a/tools/testing/selftests/bpf/prog_tests/map_kptr.c
+++ b/tools/testing/selftests/bpf/prog_tests/map_kptr.c
@@ -4,70 +4,160 @@
 
 #include "map_kptr.skel.h"
 #include "map_kptr_fail.skel.h"
+#include "rcu_tasks_trace_gp.skel.h"
 
 static void test_map_kptr_success(bool test_run)
 {
+	LIBBPF_OPTS(bpf_test_run_opts, lopts);
 	LIBBPF_OPTS(bpf_test_run_opts, opts,
 		.data_in = &pkt_v4,
 		.data_size_in = sizeof(pkt_v4),
 		.repeat = 1,
 	);
+	int key = 0, ret, cpu;
 	struct map_kptr *skel;
-	int key = 0, ret;
-	char buf[16];
+	char buf[16], *pbuf;
 
 	skel = map_kptr__open_and_load();
 	if (!ASSERT_OK_PTR(skel, "map_kptr__open_and_load"))
 		return;
 
-	ret = bpf_prog_test_run_opts(bpf_program__fd(skel->progs.test_map_kptr_ref), &opts);
-	ASSERT_OK(ret, "test_map_kptr_ref refcount");
-	ASSERT_OK(opts.retval, "test_map_kptr_ref retval");
+	ret = bpf_prog_test_run_opts(bpf_program__fd(skel->progs.test_map_kptr_ref1), &opts);
+	ASSERT_OK(ret, "test_map_kptr_ref1 refcount");
+	ASSERT_OK(opts.retval, "test_map_kptr_ref1 retval");
 	ret = bpf_prog_test_run_opts(bpf_program__fd(skel->progs.test_map_kptr_ref2), &opts);
 	ASSERT_OK(ret, "test_map_kptr_ref2 refcount");
 	ASSERT_OK(opts.retval, "test_map_kptr_ref2 retval");
 
+	ret = bpf_prog_test_run_opts(bpf_program__fd(skel->progs.test_ls_map_kptr_ref1), &lopts);
+	ASSERT_OK(ret, "test_ls_map_kptr_ref1 refcount");
+	ASSERT_OK(lopts.retval, "test_ls_map_kptr_ref1 retval");
+
+	ret = bpf_prog_test_run_opts(bpf_program__fd(skel->progs.test_ls_map_kptr_ref2), &lopts);
+	ASSERT_OK(ret, "test_ls_map_kptr_ref2 refcount");
+	ASSERT_OK(lopts.retval, "test_ls_map_kptr_ref2 retval");
+
 	if (test_run)
 		goto exit;
 
+	cpu = libbpf_num_possible_cpus();
+	if (!ASSERT_GT(cpu, 0, "libbpf_num_possible_cpus"))
+		goto exit;
+
+	pbuf = calloc(cpu, sizeof(buf));
+	if (!ASSERT_OK_PTR(pbuf, "calloc(pbuf)"))
+		goto exit;
+
 	ret = bpf_map__update_elem(skel->maps.array_map,
 				   &key, sizeof(key), buf, sizeof(buf), 0);
 	ASSERT_OK(ret, "array_map update");
-	ret = bpf_map__update_elem(skel->maps.array_map,
-				   &key, sizeof(key), buf, sizeof(buf), 0);
-	ASSERT_OK(ret, "array_map update2");
+	skel->data->ref--;
+	ret = bpf_prog_test_run_opts(bpf_program__fd(skel->progs.test_map_kptr_ref3), &opts);
+	ASSERT_OK(ret, "test_map_kptr_ref3 refcount");
+	ASSERT_OK(opts.retval, "test_map_kptr_ref3 retval");
+
+	ret = bpf_map__update_elem(skel->maps.pcpu_array_map,
+				   &key, sizeof(key), pbuf, cpu * sizeof(buf), 0);
+	ASSERT_OK(ret, "pcpu_array_map update");
+	skel->data->ref--;
+	ret = bpf_prog_test_run_opts(bpf_program__fd(skel->progs.test_map_kptr_ref3), &opts);
+	ASSERT_OK(ret, "test_map_kptr_ref3 refcount");
+	ASSERT_OK(opts.retval, "test_map_kptr_ref3 retval");
 
-	ret = bpf_map__update_elem(skel->maps.hash_map,
-				   &key, sizeof(key), buf, sizeof(buf), 0);
-	ASSERT_OK(ret, "hash_map update");
 	ret = bpf_map__delete_elem(skel->maps.hash_map, &key, sizeof(key), 0);
 	ASSERT_OK(ret, "hash_map delete");
+	skel->data->ref--;
+	ret = bpf_prog_test_run_opts(bpf_program__fd(skel->progs.test_map_kptr_ref3), &opts);
+	ASSERT_OK(ret, "test_map_kptr_ref3 refcount");
+	ASSERT_OK(opts.retval, "test_map_kptr_ref3 retval");
+
+	ret = bpf_map__delete_elem(skel->maps.pcpu_hash_map, &key, sizeof(key), 0);
+	ASSERT_OK(ret, "pcpu_hash_map delete");
+	skel->data->ref--;
+	ret = bpf_prog_test_run_opts(bpf_program__fd(skel->progs.test_map_kptr_ref3), &opts);
+	ASSERT_OK(ret, "test_map_kptr_ref3 refcount");
+	ASSERT_OK(opts.retval, "test_map_kptr_ref3 retval");
 
-	ret = bpf_map__update_elem(skel->maps.hash_malloc_map,
-				   &key, sizeof(key), buf, sizeof(buf), 0);
-	ASSERT_OK(ret, "hash_malloc_map update");
 	ret = bpf_map__delete_elem(skel->maps.hash_malloc_map, &key, sizeof(key), 0);
 	ASSERT_OK(ret, "hash_malloc_map delete");
+	skel->data->ref--;
+	ret = bpf_prog_test_run_opts(bpf_program__fd(skel->progs.test_map_kptr_ref3), &opts);
+	ASSERT_OK(ret, "test_map_kptr_ref3 refcount");
+	ASSERT_OK(opts.retval, "test_map_kptr_ref3 retval");
+
+	ret = bpf_map__delete_elem(skel->maps.pcpu_hash_malloc_map, &key, sizeof(key), 0);
+	ASSERT_OK(ret, "pcpu_hash_malloc_map delete");
+	skel->data->ref--;
+	ret = bpf_prog_test_run_opts(bpf_program__fd(skel->progs.test_map_kptr_ref3), &opts);
+	ASSERT_OK(ret, "test_map_kptr_ref3 refcount");
+	ASSERT_OK(opts.retval, "test_map_kptr_ref3 retval");
 
-	ret = bpf_map__update_elem(skel->maps.lru_hash_map,
-				   &key, sizeof(key), buf, sizeof(buf), 0);
-	ASSERT_OK(ret, "lru_hash_map update");
 	ret = bpf_map__delete_elem(skel->maps.lru_hash_map, &key, sizeof(key), 0);
 	ASSERT_OK(ret, "lru_hash_map delete");
+	skel->data->ref--;
+	ret = bpf_prog_test_run_opts(bpf_program__fd(skel->progs.test_map_kptr_ref3), &opts);
+	ASSERT_OK(ret, "test_map_kptr_ref3 refcount");
+	ASSERT_OK(opts.retval, "test_map_kptr_ref3 retval");
+
+	ret = bpf_map__delete_elem(skel->maps.lru_pcpu_hash_map, &key, sizeof(key), 0);
+	ASSERT_OK(ret, "lru_pcpu_hash_map delete");
+	skel->data->ref--;
+	ret = bpf_prog_test_run_opts(bpf_program__fd(skel->progs.test_map_kptr_ref3), &opts);
+	ASSERT_OK(ret, "test_map_kptr_ref3 refcount");
+	ASSERT_OK(opts.retval, "test_map_kptr_ref3 retval");
 
+	ret = bpf_prog_test_run_opts(bpf_program__fd(skel->progs.test_ls_map_kptr_ref_del), &lopts);
+	ASSERT_OK(ret, "test_ls_map_kptr_ref_del delete");
+	skel->data->ref--;
+	ASSERT_OK(lopts.retval, "test_ls_map_kptr_ref_del retval");
+
+	free(pbuf);
 exit:
 	map_kptr__destroy(skel);
 }
 
-void test_map_kptr(void)
+static int kern_sync_rcu_tasks_trace(struct rcu_tasks_trace_gp *rcu)
 {
-	if (test__start_subtest("success")) {
+	long gp_seq = READ_ONCE(rcu->bss->gp_seq);
+	LIBBPF_OPTS(bpf_test_run_opts, opts);
+
+	if (!ASSERT_OK(bpf_prog_test_run_opts(bpf_program__fd(rcu->progs.do_call_rcu_tasks_trace),
+					      &opts), "do_call_rcu_tasks_trace"))
+		return -EFAULT;
+	if (!ASSERT_OK(opts.retval, "opts.retval == 0"))
+		return -EFAULT;
+	while (gp_seq == READ_ONCE(rcu->bss->gp_seq))
+		sched_yield();
+	return 0;
+}
+
+void serial_test_map_kptr(void)
+{
+	struct rcu_tasks_trace_gp *skel;
+
+	RUN_TESTS(map_kptr_fail);
+
+	skel = rcu_tasks_trace_gp__open_and_load();
+	if (!ASSERT_OK_PTR(skel, "rcu_tasks_trace_gp__open_and_load"))
+		return;
+	if (!ASSERT_OK(rcu_tasks_trace_gp__attach(skel), "rcu_tasks_trace_gp__attach"))
+		goto end;
+
+	if (test__start_subtest("success-map")) {
+		test_map_kptr_success(true);
+
+		ASSERT_OK(kern_sync_rcu_tasks_trace(skel), "sync rcu_tasks_trace");
+		ASSERT_OK(kern_sync_rcu(), "sync rcu");
+		/* Observe refcount dropping to 1 on bpf_map_free_deferred */
 		test_map_kptr_success(false);
-		/* Do test_run twice, so that we see refcount going back to 1
-		 * after we leave it in map from first iteration.
-		 */
+
+		ASSERT_OK(kern_sync_rcu_tasks_trace(skel), "sync rcu_tasks_trace");
+		ASSERT_OK(kern_sync_rcu(), "sync rcu");
+		/* Observe refcount dropping to 1 on synchronous delete elem */
 		test_map_kptr_success(true);
 	}
 
-	RUN_TESTS(map_kptr_fail);
+end:
+	rcu_tasks_trace_gp__destroy(skel);
+	return;
 }