diff --git a/tools/testing/selftests/bpf/prog_tests/dynptr.c b/tools/testing/selftests/bpf/prog_tests/dynptr.c index 3c7aa82b98e2..bcf80b9f7c27 100644 --- a/tools/testing/selftests/bpf/prog_tests/dynptr.c +++ b/tools/testing/selftests/bpf/prog_tests/dynptr.c @@ -22,7 +22,8 @@ static struct { {"add_dynptr_to_map2", "invalid indirect read from stack"}, {"data_slice_out_of_bounds_ringbuf", "value is outside of the allowed memory range"}, {"data_slice_out_of_bounds_map_value", "value is outside of the allowed memory range"}, - {"data_slice_use_after_release", "invalid mem access 'scalar'"}, + {"data_slice_use_after_release1", "invalid mem access 'scalar'"}, + {"data_slice_use_after_release2", "invalid mem access 'scalar'"}, {"data_slice_missing_null_check1", "invalid mem access 'mem_or_null'"}, {"data_slice_missing_null_check2", "invalid mem access 'mem_or_null'"}, {"invalid_helper1", "invalid indirect read from stack"}, diff --git a/tools/testing/selftests/bpf/progs/dynptr_fail.c b/tools/testing/selftests/bpf/progs/dynptr_fail.c index b5e0a87f0a36..b0f08ff024fb 100644 --- a/tools/testing/selftests/bpf/progs/dynptr_fail.c +++ b/tools/testing/selftests/bpf/progs/dynptr_fail.c @@ -248,7 +248,7 @@ int data_slice_out_of_bounds_map_value(void *ctx) /* A data slice can't be used after it has been released */ SEC("?raw_tp") -int data_slice_use_after_release(void *ctx) +int data_slice_use_after_release1(void *ctx) { struct bpf_dynptr ptr; struct sample *sample; @@ -272,6 +272,42 @@ done: return 0; } +/* A data slice can't be used after it has been released. + * + * This tests the case where the data slice tracks a dynptr (ptr2) + * that is at a non-zero offset from the frame pointer (ptr1 is at fp, + * ptr2 is at fp - 16). + */ +SEC("?raw_tp") +int data_slice_use_after_release2(void *ctx) +{ + struct bpf_dynptr ptr1, ptr2; + struct sample *sample; + + bpf_ringbuf_reserve_dynptr(&ringbuf, 64, 0, &ptr1); + bpf_ringbuf_reserve_dynptr(&ringbuf, sizeof(*sample), 0, &ptr2); + + sample = bpf_dynptr_data(&ptr2, 0, sizeof(*sample)); + if (!sample) + goto done; + + sample->pid = 23; + + bpf_ringbuf_submit_dynptr(&ptr2, 0); + + /* this should fail */ + sample->pid = 23; + + bpf_ringbuf_submit_dynptr(&ptr1, 0); + + return 0; + +done: + bpf_ringbuf_discard_dynptr(&ptr2, 0); + bpf_ringbuf_discard_dynptr(&ptr1, 0); + return 0; +} + /* A data slice must be first checked for NULL */ SEC("?raw_tp") int data_slice_missing_null_check1(void *ctx)