projects / lttng-modules.git / blame
| Commit | Line | Data |
|---|---|---|
| b7cdc182 | 1 | /* SPDX-License-Identifier: (GPL-2.0-only or LGPL-2.1-only) |
| dc923e75 MJ |
2 | * |
| 3 | * lttng-context-vsuid.c | |
| 4 | * | |
| 5 | * LTTng namespaced saved set-user-ID context. | |
| 6 | * | |
| 7 | * Copyright (C) 2009-2012 Mathieu Desnoyers <mathieu.desnoyers@efficios.com> | |
| 8 | * 2019 Michael Jeanson <mjeanson@efficios.com> | |
| 9 | * | |
| 10 | */ | |
| 11 | ||
| 12 | #include <linux/module.h> | |
| 13 | #include <linux/sched.h> | |
| 2df37e95 MD |
14 | #include <lttng/events.h> |
| 15 | #include <lttng/tracer.h> | |
| 24591303 | 16 | #include <ringbuffer/frontend_types.h> |
| dc923e75 MJ |
17 | #include <wrapper/vmalloc.h> |
| 18 | #include <wrapper/user_namespace.h> | |
| 19 | ||
| 20 | static | |
| 21 | size_t vsuid_get_size(size_t offset) | |
| 22 | { | |
| 23 | size_t size = 0; | |
| 24 | ||
| 25 | size += lib_ring_buffer_align(offset, lttng_alignof(uid_t)); | |
| 26 | size += sizeof(uid_t); | |
| 27 | return size; | |
| 28 | } | |
| 29 | ||
| 30 | static | |
| 31 | void vsuid_record(struct lttng_ctx_field *field, | |
| 32 | struct lib_ring_buffer_ctx *ctx, | |
| 33 | struct lttng_channel *chan) | |
| 34 | { | |
| 35 | uid_t vsuid; | |
| 36 | ||
| 37 | vsuid = lttng_current_vsuid(); | |
| 38 | lib_ring_buffer_align_ctx(ctx, lttng_alignof(vsuid)); | |
| 39 | chan->ops->event_write(ctx, &vsuid, sizeof(vsuid)); | |
| 40 | } | |
| 41 | ||
| 42 | static | |
| 43 | void vsuid_get_value(struct lttng_ctx_field *field, | |
| 44 | struct lttng_probe_ctx *lttng_probe_ctx, | |
| 45 | union lttng_ctx_value *value) | |
| 46 | { | |
| 47 | value->s64 = lttng_current_vsuid(); | |
| 48 | } | |
| 49 | ||
| 50 | int lttng_add_vsuid_to_ctx(struct lttng_ctx **ctx) | |
| 51 | { | |
| 52 | struct lttng_ctx_field *field; | |
| 53 | ||
| 54 | field = lttng_append_context(ctx); | |
| 55 | if (!field) | |
| 56 | return -ENOMEM; | |
| 57 | if (lttng_find_context(*ctx, "vsuid")) { | |
| 58 | lttng_remove_context_field(ctx, field); | |
| 59 | return -EEXIST; | |
| 60 | } | |
| 61 | field->event_field.name = "vsuid"; | |
| 62 | field->event_field.type.atype = atype_integer; | |
| ceabb767 MD |
63 | field->event_field.type.u.integer.size = sizeof(uid_t) * CHAR_BIT; |
| 64 | field->event_field.type.u.integer.alignment = lttng_alignof(uid_t) * CHAR_BIT; | |
| 65 | field->event_field.type.u.integer.signedness = lttng_is_signed_type(uid_t); | |
| 66 | field->event_field.type.u.integer.reverse_byte_order = 0; | |
| 67 | field->event_field.type.u.integer.base = 10; | |
| 68 | field->event_field.type.u.integer.encoding = lttng_encode_none; | |
| dc923e75 MJ |
69 | field->get_size = vsuid_get_size; |
| 70 | field->record = vsuid_record; | |
| 71 | field->get_value = vsuid_get_value; | |
| 72 | lttng_context_update(*ctx); | |
| 263b6c88 | 73 | wrapper_vmalloc_sync_mappings(); |
| dc923e75 MJ |
74 | return 0; |
| 75 | } | |
| 76 | EXPORT_SYMBOL_GPL(lttng_add_vsuid_to_ctx); |