diff --git a/tools/testing/selftests/bpf/progs/dynptr_fail.c b/tools/testing/selftests/bpf/progs/dynptr_fail.c index 1cbec5468879..5950ad6ec2e6 100644 --- a/tools/testing/selftests/bpf/progs/dynptr_fail.c +++ b/tools/testing/selftests/bpf/progs/dynptr_fail.c @@ -900,3 +900,195 @@ int dynptr_partial_slot_invalidate(struct __sk_buff *ctx) ); return 0; } + +/* Test that it is allowed to overwrite unreferenced dynptr. */ +SEC("?raw_tp") +__success +int dynptr_overwrite_unref(void *ctx) +{ + struct bpf_dynptr ptr; + + if (get_map_val_dynptr(&ptr)) + return 0; + if (get_map_val_dynptr(&ptr)) + return 0; + if (get_map_val_dynptr(&ptr)) + return 0; + + return 0; +} + +/* Test that slices are invalidated on reinitializing a dynptr. */ +SEC("?raw_tp") +__failure __msg("invalid mem access 'scalar'") +int dynptr_invalidate_slice_reinit(void *ctx) +{ + struct bpf_dynptr ptr; + __u8 *p; + + if (get_map_val_dynptr(&ptr)) + return 0; + p = bpf_dynptr_data(&ptr, 0, 1); + if (!p) + return 0; + if (get_map_val_dynptr(&ptr)) + return 0; + /* this should fail */ + return *p; +} + +/* Invalidation of dynptr slices on destruction of dynptr should not miss + * mem_or_null pointers. + */ +SEC("?raw_tp") +__failure __msg("R1 type=scalar expected=percpu_ptr_") +int dynptr_invalidate_slice_or_null(void *ctx) +{ + struct bpf_dynptr ptr; + __u8 *p; + + if (get_map_val_dynptr(&ptr)) + return 0; + + p = bpf_dynptr_data(&ptr, 0, 1); + *(__u8 *)&ptr = 0; + /* this should fail */ + bpf_this_cpu_ptr(p); + return 0; +} + +/* Destruction of dynptr should also any slices obtained from it */ +SEC("?raw_tp") +__failure __msg("R7 invalid mem access 'scalar'") +int dynptr_invalidate_slice_failure(void *ctx) +{ + struct bpf_dynptr ptr1; + struct bpf_dynptr ptr2; + __u8 *p1, *p2; + + if (get_map_val_dynptr(&ptr1)) + return 0; + if (get_map_val_dynptr(&ptr2)) + return 0; + + p1 = bpf_dynptr_data(&ptr1, 0, 1); + if (!p1) + return 0; + p2 = bpf_dynptr_data(&ptr2, 0, 1); + if (!p2) + return 0; + + *(__u8 *)&ptr1 = 0; + /* this should fail */ + return *p1; +} + +/* Invalidation of slices should be scoped and should not prevent dereferencing + * slices of another dynptr after destroying unrelated dynptr + */ +SEC("?raw_tp") +__success +int dynptr_invalidate_slice_success(void *ctx) +{ + struct bpf_dynptr ptr1; + struct bpf_dynptr ptr2; + __u8 *p1, *p2; + + if (get_map_val_dynptr(&ptr1)) + return 1; + if (get_map_val_dynptr(&ptr2)) + return 1; + + p1 = bpf_dynptr_data(&ptr1, 0, 1); + if (!p1) + return 1; + p2 = bpf_dynptr_data(&ptr2, 0, 1); + if (!p2) + return 1; + + *(__u8 *)&ptr1 = 0; + return *p2; +} + +/* Overwriting referenced dynptr should be rejected */ +SEC("?raw_tp") +__failure __msg("cannot overwrite referenced dynptr") +int dynptr_overwrite_ref(void *ctx) +{ + struct bpf_dynptr ptr; + + bpf_ringbuf_reserve_dynptr(&ringbuf, 64, 0, &ptr); + /* this should fail */ + if (get_map_val_dynptr(&ptr)) + bpf_ringbuf_discard_dynptr(&ptr, 0); + return 0; +} + +/* Reject writes to dynptr slot from bpf_dynptr_read */ +SEC("?raw_tp") +__failure __msg("potential write to dynptr at off=-16") +int dynptr_read_into_slot(void *ctx) +{ + union { + struct { + char _pad[48]; + struct bpf_dynptr ptr; + }; + char buf[64]; + } data; + + bpf_ringbuf_reserve_dynptr(&ringbuf, 64, 0, &data.ptr); + /* this should fail */ + bpf_dynptr_read(data.buf, sizeof(data.buf), &data.ptr, 0, 0); + + return 0; +} + +/* Reject writes to dynptr slot for uninit arg */ +SEC("?raw_tp") +__failure __msg("potential write to dynptr at off=-16") +int uninit_write_into_slot(void *ctx) +{ + struct { + char buf[64]; + struct bpf_dynptr ptr; + } data; + + bpf_ringbuf_reserve_dynptr(&ringbuf, 80, 0, &data.ptr); + /* this should fail */ + bpf_get_current_comm(data.buf, 80); + + return 0; +} + +static int callback(__u32 index, void *data) +{ + *(__u32 *)data = 123; + + return 0; +} + +/* If the dynptr is written into in a callback function, its data + * slices should be invalidated as well. + */ +SEC("?raw_tp") +__failure __msg("invalid mem access 'scalar'") +int invalid_data_slices(void *ctx) +{ + struct bpf_dynptr ptr; + __u32 *slice; + + if (get_map_val_dynptr(&ptr)) + return 0; + + slice = bpf_dynptr_data(&ptr, 0, sizeof(__u32)); + if (!slice) + return 0; + + bpf_loop(10, callback, &ptr, 0); + + /* this should fail */ + *slice = 1; + + return 0; +}