* Copyright (C) 2020 Francis Deslauriers <francis.deslauriers@efficios.com>
*/
+#include <asm/barrier.h>
#include <linux/bug.h>
#include <lttng/lttng-bytecode.h>
#include <lttng/msgpack.h>
#include <lttng/event-notifier-notification.h>
#include <lttng/events-internal.h>
-#include <wrapper/barrier.h>
+#include <lttng/probe-user.h>
/*
* The capture buffer size needs to be below 1024 bytes to avoid the
*/
#define CAPTURE_BUFFER_SIZE 512
+#define MSG_WRITE_NIL_LEN 1
+
struct lttng_event_notifier_notification {
int notification_fd;
uint64_t event_notifier_token;
*/
ret = lttng_msgpack_begin_map(writer, 2);
if (ret) {
- WARN_ON_ONCE(1);
goto end;
}
ret = lttng_msgpack_write_str(writer, "type");
if (ret) {
- WARN_ON_ONCE(1);
goto end;
}
ret = lttng_msgpack_write_str(writer, "enum");
if (ret) {
- WARN_ON_ONCE(1);
goto end;
}
ret = lttng_msgpack_write_str(writer, "value");
if (ret) {
- WARN_ON_ONCE(1);
goto end;
}
case LTTNG_INTERPRETER_TYPE_SIGNED_ENUM:
ret = lttng_msgpack_write_signed_integer(writer, output->u.s);
if (ret) {
- WARN_ON_ONCE(1);
goto end;
}
break;
case LTTNG_INTERPRETER_TYPE_UNSIGNED_ENUM:
ret = lttng_msgpack_write_signed_integer(writer, output->u.u);
if (ret) {
- WARN_ON_ONCE(1);
goto end;
}
break;
default:
- WARN_ON(1);
+ WARN_ON_ONCE(1);
+ ret = -1;
+ goto end;
}
ret = lttng_msgpack_end_map(writer);
- if (ret)
- WARN_ON_ONCE(1);
-
end:
return ret;
}
static
-int64_t capture_sequence_element_signed(uint8_t *ptr,
- const struct lttng_kernel_type_integer *type)
+int capture_sequence_element_signed(uint8_t *ptr,
+ const struct lttng_kernel_type_integer *type,
+ int64_t *_value)
{
int64_t value = 0;
unsigned int size = type->size;
+ bool user = type->user;
bool byte_order_reversed = type->reverse_byte_order;
switch (size) {
case 8:
- value = *ptr;
+ {
+ int8_t tmp;
+
+ if (user) {
+ if (lttng_copy_from_user_check_nofault(&tmp, ptr, sizeof(int8_t)))
+ return -1;
+ } else {
+ tmp = *ptr;
+ }
+ value = tmp;
break;
+ }
case 16:
{
int16_t tmp;
- tmp = *(int16_t *) ptr;
+
+ if (user) {
+ if (lttng_copy_from_user_check_nofault(&tmp, ptr, sizeof(int16_t)))
+ return -1;
+ } else {
+ tmp = *(int16_t *) ptr;
+ }
if (byte_order_reversed)
__swab16s(&tmp);
-
value = tmp;
break;
}
case 32:
{
int32_t tmp;
- tmp = *(int32_t *) ptr;
+
+ if (user) {
+ if (lttng_copy_from_user_check_nofault(&tmp, ptr, sizeof(int32_t)))
+ return -1;
+ } else {
+ tmp = *(int32_t *) ptr;
+ }
if (byte_order_reversed)
__swab32s(&tmp);
-
value = tmp;
break;
}
case 64:
{
int64_t tmp;
- tmp = *(int64_t *) ptr;
+
+ if (user) {
+ if (lttng_copy_from_user_check_nofault(&tmp, ptr, sizeof(int64_t)))
+ return -1;
+ } else {
+ tmp = *(int64_t *) ptr;
+ }
if (byte_order_reversed)
__swab64s(&tmp);
-
value = tmp;
break;
}
default:
- WARN_ON(1);
+ WARN_ON_ONCE(1);
+ return -1;
}
- return value;
+ *_value = value;
+ return 0;
}
static
-uint64_t capture_sequence_element_unsigned(uint8_t *ptr,
- const struct lttng_kernel_type_integer *type)
+int capture_sequence_element_unsigned(uint8_t *ptr,
+ const struct lttng_kernel_type_integer *type,
+ uint64_t *_value)
{
uint64_t value = 0;
unsigned int size = type->size;
+ bool user = type->user;
bool byte_order_reversed = type->reverse_byte_order;
switch (size) {
case 8:
- value = *ptr;
+ {
+ uint8_t tmp;
+
+ if (user) {
+ if (lttng_copy_from_user_check_nofault(&tmp, ptr, sizeof(uint8_t)))
+ return -1;
+ } else {
+ tmp = *ptr;
+ }
+ value = tmp;
break;
+ }
case 16:
{
uint16_t tmp;
- tmp = *(uint16_t *) ptr;
+
+ if (user) {
+ if (lttng_copy_from_user_check_nofault(&tmp, ptr, sizeof(uint16_t)))
+ return -1;
+ } else {
+ tmp = *(uint16_t *) ptr;
+ }
if (byte_order_reversed)
__swab16s(&tmp);
-
value = tmp;
break;
}
case 32:
{
uint32_t tmp;
- tmp = *(uint32_t *) ptr;
+
+ if (user) {
+ if (lttng_copy_from_user_check_nofault(&tmp, ptr, sizeof(uint32_t)))
+ return -1;
+ } else {
+ tmp = *(uint32_t *) ptr;
+ }
if (byte_order_reversed)
__swab32s(&tmp);
-
value = tmp;
break;
}
case 64:
{
uint64_t tmp;
- tmp = *(uint64_t *) ptr;
+
+ if (user) {
+ if (lttng_copy_from_user_check_nofault(&tmp, ptr, sizeof(uint64_t)))
+ return -1;
+ } else {
+ tmp = *(uint64_t *) ptr;
+ }
if (byte_order_reversed)
__swab64s(&tmp);
-
value = tmp;
break;
}
default:
- WARN_ON(1);
+ WARN_ON_ONCE(1);
+ return -1;
}
- return value;
+ *_value = value;
+ return 0;
}
+static
int capture_sequence(struct lttng_msgpack_writer *writer,
struct lttng_interpreter_output *output)
{
ret = lttng_msgpack_begin_array(writer, output->u.sequence.nr_elem);
if (ret) {
- WARN_ON_ONCE(1);
goto end;
}
break;
default:
/* Capture of array of non-integer are not supported. */
- WARN_ON(1);
+ WARN_ON_ONCE(1);
+ ret = -1;
+ goto end;
}
signedness = integer_type->signedness;
for (i = 0; i < output->u.sequence.nr_elem; i++) {
if (signedness) {
- ret = lttng_msgpack_write_signed_integer(writer,
- capture_sequence_element_signed(ptr, integer_type));
+ int64_t v;
+
+ ret = capture_sequence_element_signed(ptr, integer_type, &v);
+ if (ret) {
+ goto end;
+ }
+ ret = lttng_msgpack_write_signed_integer(writer, v);
if (ret) {
- WARN_ON_ONCE(1);
goto end;
}
} else {
- ret = lttng_msgpack_write_unsigned_integer(writer,
- capture_sequence_element_unsigned(ptr, integer_type));
+ uint64_t v;
+
+ ret = capture_sequence_element_unsigned(ptr, integer_type, &v);
+ if (ret) {
+ goto end;
+ }
+ ret = lttng_msgpack_write_unsigned_integer(writer, v);
if (ret) {
- WARN_ON_ONCE(1);
goto end;
}
}
* take into account that the next element might be further
* away.
*/
- WARN_ON(integer_type->alignment > integer_type->size);
+ WARN_ON_ONCE(integer_type->alignment > integer_type->size);
/* Size is in number of bits. */
ptr += (integer_type->size / CHAR_BIT) ;
}
ret = lttng_msgpack_end_array(writer);
- if (ret)
- WARN_ON_ONCE(1);
end:
return ret;
}
switch (output->type) {
case LTTNG_INTERPRETER_TYPE_S64:
ret = lttng_msgpack_write_signed_integer(writer, output->u.s);
- if (ret) {
- WARN_ON_ONCE(1);
- goto end;
- }
break;
case LTTNG_INTERPRETER_TYPE_U64:
ret = lttng_msgpack_write_unsigned_integer(writer, output->u.u);
- if (ret) {
- WARN_ON_ONCE(1);
- goto end;
- }
break;
case LTTNG_INTERPRETER_TYPE_STRING:
- ret = lttng_msgpack_write_str(writer, output->u.str.str);
- if (ret) {
- WARN_ON_ONCE(1);
- goto end;
+ if (output->u.str.user) {
+ ret = lttng_msgpack_write_user_str(writer, output->u.str.user_str);
+ } else {
+ ret = lttng_msgpack_write_str(writer, output->u.str.str);
}
break;
case LTTNG_INTERPRETER_TYPE_SEQUENCE:
ret = capture_sequence(writer, output);
- if (ret) {
- WARN_ON_ONCE(1);
- goto end;
- }
break;
case LTTNG_INTERPRETER_TYPE_SIGNED_ENUM:
case LTTNG_INTERPRETER_TYPE_UNSIGNED_ENUM:
ret = capture_enum(writer, output);
- if (ret) {
- WARN_ON_ONCE(1);
- goto end;
- }
break;
default:
ret = -1;
- WARN_ON(1);
+ WARN_ON_ONCE(1);
}
-end:
return ret;
}
int notification_append_empty_capture(
struct lttng_event_notifier_notification *notif)
{
- int ret = lttng_msgpack_write_nil(¬if->writer);
- if (ret)
- WARN_ON_ONCE(1);
-
- return ret;
+ return lttng_msgpack_write_nil(¬if->writer);
}
static
ret = lttng_msgpack_begin_array(writer, event_notifier->priv->num_captures);
if (ret) {
- WARN_ON_ONCE(1);
goto end;
}
int ret;
/*
- * lttng_smp_load_acquire paired with lttng_smp_store_release orders
- * creation of the error counter and setting error_counter_len
- * before the error_counter is used.
+ * smp_load_acquire paired with smp_store_release orders creation of
+ * the error counter and setting error_counter_len before the
+ * error_counter is used.
*/
- error_counter = lttng_smp_load_acquire(&event_notifier_group->error_counter);
+ error_counter = smp_load_acquire(&event_notifier_group->error_counter);
/* This group may not have an error counter attached to it. */
if (!error_counter)
return;
struct lttng_kernel_event_notifier *event_notifier)
{
struct lttng_event_notifier_group *event_notifier_group = event_notifier->priv->group;
- struct lib_ring_buffer_ctx ctx;
+ struct lttng_kernel_ring_buffer_ctx ctx;
struct lttng_kernel_abi_event_notifier_notification kernel_notif;
size_t capture_buffer_content_len, reserve_size;
int ret;
return;
}
- lib_ring_buffer_align_ctx(&ctx, lttng_alignof(kernel_notif));
-
/* Write the notif structure. */
event_notifier_group->ops->event_write(&ctx, &kernel_notif,
- sizeof(kernel_notif));
+ sizeof(kernel_notif), lttng_alignof(kernel_notif));
/*
* Write the capture buffer. No need to realigned as the below is a raw
* char* buffer.
*/
event_notifier_group->ops->event_write(&ctx, ¬if->capture_buf,
- capture_buffer_content_len);
+ capture_buffer_content_len, 1);
event_notifier_group->ops->event_commit(&ctx);
irq_work_queue(&event_notifier_group->wakeup_pending);
}
+/*
+ * Validate that the buffer has enough room to hold empty capture fields.
+ */
+static
+bool validate_buffer_len(struct lttng_event_notifier_notification *notif, size_t captures_left)
+{
+ if (notif->writer.end_write_pos - notif->writer.write_pos < MSG_WRITE_NIL_LEN * captures_left)
+ return false;
+ return true;
+}
+
void lttng_event_notifier_notification_send(struct lttng_kernel_event_notifier *event_notifier,
const char *stack_data,
- struct lttng_probe_ctx *probe_ctx,
+ struct lttng_kernel_probe_ctx *probe_ctx,
struct lttng_kernel_notification_ctx *notif_ctx)
{
struct lttng_event_notifier_notification notif = { 0 };
- int ret;
+ size_t captures_left;
- if (unlikely(!READ_ONCE(event_notifier->parent.enabled)))
- return;
+ if (notification_init(¬if, event_notifier))
+ goto error;
- ret = notification_init(¬if, event_notifier);
- if (ret) {
- WARN_ON_ONCE(1);
- goto end;
- }
+ captures_left = event_notifier->priv->num_captures;
+ if (!validate_buffer_len(¬if, captures_left))
+ goto error;
if (unlikely(notif_ctx->eval_capture)) {
struct lttng_kernel_bytecode_runtime *capture_bc_runtime;
list_for_each_entry_rcu(capture_bc_runtime,
&event_notifier->priv->capture_bytecode_runtime_head, node) {
struct lttng_interpreter_output output;
+ uint8_t *save_pos;
+ int ret = -1;
+ lttng_msgpack_save_writer_pos(¬if.writer, &save_pos);
+ captures_left--;
if (capture_bc_runtime->interpreter_func(capture_bc_runtime,
stack_data, probe_ctx, &output) == LTTNG_KERNEL_BYTECODE_INTERPRETER_OK)
ret = notification_append_capture(¬if, &output);
- else
+ if (ret || !validate_buffer_len(¬if, captures_left)) {
+ /*
+ * On append capture error or if the generated
+ * buffer data would not leave enough room to
+ * write empty capture fields for the remaining
+ * fields, skip the field capture by restoring
+ * the msgpack writer position and writing an
+ * empty capture field.
+ */
+ lttng_msgpack_restore_writer_pos(¬if.writer, save_pos);
ret = notification_append_empty_capture(¬if);
-
- if (ret)
- printk(KERN_WARNING "Error appending capture to notification");
+ WARN_ON_ONCE(ret);
+ }
}
}
+ if (notif.has_captures && lttng_msgpack_end_array(¬if.writer))
+ goto error;
+
/*
* Send the notification (including the capture buffer) to the
* sessiond.
*/
notification_send(¬if, event_notifier);
-end:
+ return;
+
+error:
+ record_error(event_notifier);
return;
}
projects / lttng-modules.git / blobdiff