[pulseaudio-discuss] [PATCH] virtual sources and sinks: Fix possible segfault

[Georg Chini]

Several virtual sources and sinks apart from module-echo-cancel also query the master
sink or source to estimate the current latency. Those modules might potentially show
the bug that is described for module-echo-cancel in bug 100277.

This patch checks in the message handlers for the PA_{SINK,SOURCE}_MESSAGE_GET_LATENCY
if the master sink or source is valid and returns 0 as latency if not.
---
 src/modules/module-ladspa-sink.c           | 3 ++-
 src/modules/module-remap-sink.c            | 3 ++-
 src/modules/module-remap-source.c          | 3 ++-
 src/modules/module-virtual-sink.c          | 3 ++-
 src/modules/module-virtual-source.c        | 3 ++-
 src/modules/module-virtual-surround-sink.c | 3 ++-
 6 files changed, 12 insertions(+), 6 deletions(-)

diff --git a/src/modules/module-ladspa-sink.c b/src/modules/module-ladspa-sink.c
index 7b2e651f..86ab4a6f 100644
--- a/src/modules/module-ladspa-sink.c
+++ b/src/modules/module-ladspa-sink.c
@@ -347,7 +347,8 @@ static int sink_process_msg_cb(pa_msgobject *o, int code, void *data, int64_t of
          * make sure we don't access it in that time. Also, the
          * sink input is first shut down, the sink second. */
         if (!PA_SINK_IS_LINKED(u->sink->thread_info.state) ||
-                !PA_SINK_INPUT_IS_LINKED(u->sink_input->thread_info.state)) {
+            !PA_SINK_INPUT_IS_LINKED(u->sink_input->thread_info.state) ||
+            !u->sink_input->sink) {
             *((int64_t*) data) = 0;
             return 0;
         }
diff --git a/src/modules/module-remap-sink.c b/src/modules/module-remap-sink.c
index 37f4f56c..534874d7 100644
--- a/src/modules/module-remap-sink.c
+++ b/src/modules/module-remap-sink.c
@@ -83,7 +83,8 @@ static int sink_process_msg(pa_msgobject *o, int code, void *data, int64_t offse
             /* The sink is _put() before the sink input is, so let's
              * make sure we don't access it yet */
             if (!PA_SINK_IS_LINKED(u->sink->thread_info.state) ||
-                !PA_SINK_INPUT_IS_LINKED(u->sink_input->thread_info.state)) {
+                !PA_SINK_INPUT_IS_LINKED(u->sink_input->thread_info.state) ||
+                !u->sink_input->sink) {
                 *((int64_t*) data) = 0;
                 return 0;
             }
diff --git a/src/modules/module-remap-source.c b/src/modules/module-remap-source.c
index 0bdeb381..25772ecd 100644
--- a/src/modules/module-remap-source.c
+++ b/src/modules/module-remap-source.c
@@ -91,7 +91,8 @@ static int source_process_msg_cb(pa_msgobject *o, int code, void *data, int64_t
              * make sure we don't access it in that time. Also, the
              * source output is first shut down, the source second. */
             if (!PA_SOURCE_IS_LINKED(u->source->thread_info.state) ||
-                !PA_SOURCE_OUTPUT_IS_LINKED(u->source_output->thread_info.state)) {
+                !PA_SOURCE_OUTPUT_IS_LINKED(u->source_output->thread_info.state) ||
+                !u->source_output->source) {
                 *((int64_t*) data) = 0;
                 return 0;
             }
diff --git a/src/modules/module-virtual-sink.c b/src/modules/module-virtual-sink.c
index 4fa4a56e..6175ca8e 100644
--- a/src/modules/module-virtual-sink.c
+++ b/src/modules/module-virtual-sink.c
@@ -94,7 +94,8 @@ static int sink_process_msg_cb(pa_msgobject *o, int code, void *data, int64_t of
              * make sure we don't access it in that time. Also, the
              * sink input is first shut down, the sink second. */
             if (!PA_SINK_IS_LINKED(u->sink->thread_info.state) ||
-                !PA_SINK_INPUT_IS_LINKED(u->sink_input->thread_info.state)) {
+                !PA_SINK_INPUT_IS_LINKED(u->sink_input->thread_info.state) ||
+                !u->sink_input->sink) {
                 *((int64_t*) data) = 0;
                 return 0;
             }
diff --git a/src/modules/module-virtual-source.c b/src/modules/module-virtual-source.c
index 42aefd05..dd0b40e1 100644
--- a/src/modules/module-virtual-source.c
+++ b/src/modules/module-virtual-source.c
@@ -175,7 +175,8 @@ static int source_process_msg_cb(pa_msgobject *o, int code, void *data, int64_t
              * make sure we don't access it in that time. Also, the
              * source output is first shut down, the source second. */
             if (!PA_SOURCE_IS_LINKED(u->source->thread_info.state) ||
-                !PA_SOURCE_OUTPUT_IS_LINKED(u->source_output->thread_info.state)) {
+                !PA_SOURCE_OUTPUT_IS_LINKED(u->source_output->thread_info.state) ||
+                !u->source_output->source) {
                 *((pa_usec_t*) data) = 0;
                 return 0;
             }
diff --git a/src/modules/module-virtual-surround-sink.c b/src/modules/module-virtual-surround-sink.c
index 23c6bdc5..94ea9f4a 100644
--- a/src/modules/module-virtual-surround-sink.c
+++ b/src/modules/module-virtual-surround-sink.c
@@ -122,7 +122,8 @@ static int sink_process_msg_cb(pa_msgobject *o, int code, void *data, int64_t of
              * make sure we don't access it in that time. Also, the
              * sink input is first shut down, the sink second. */
             if (!PA_SINK_IS_LINKED(u->sink->thread_info.state) ||
-                !PA_SINK_INPUT_IS_LINKED(u->sink_input->thread_info.state)) {
+                !PA_SINK_INPUT_IS_LINKED(u->sink_input->thread_info.state) ||
+                !u->sink_input->sink) {
                 *((int64_t*) data) = 0;
                 return 0;
             }
-- 
2.11.0