[libqb] [PATCH 5/6] IPC: check for null ringbuffer

[Angus Salkeld]

Signed-off-by: Angus Salkeld 
---
 lib/ipc_shm.c |   34 ++++++++++++++++++++++++++--------
 lib/ipcs.c    |    3 ++-
 2 files changed, 28 insertions(+), 9 deletions(-)

diff --git a/lib/ipc_shm.c b/lib/ipc_shm.c
index e9b60d5..114a317 100644
--- a/lib/ipc_shm.c
+++ b/lib/ipc_shm.c
@@ -57,6 +57,10 @@ static ssize_t qb_ipc_shm_sendv(struct qb_ipc_one_way *one_way,
    int32_t i;
    char *pt = NULL;

+	if (one_way->u.shm.rb == NULL) {
+		return -EIDRM;
+	}
+
    for (i = 0; i < iov_len; i++) {
    	total_size += iov[i].iov_len;
    }
@@ -82,10 +86,14 @@ static ssize_t qb_ipc_shm_recv(struct qb_ipc_one_way *one_way,
    		       size_t msg_len,
    		       int32_t ms_timeout)
 {
-	ssize_t res = qb_rb_chunk_read(one_way->u.shm.rb,
-				       (void *)msg_ptr,
-				       msg_len,
-				       ms_timeout);
+	ssize_t res;
+	if (one_way->u.shm.rb == NULL) {
+		return -EIDRM;
+	}
+	res = qb_rb_chunk_read(one_way->u.shm.rb,
+			       (void *)msg_ptr,
+			       msg_len,
+			       ms_timeout);
    if (res == -ETIMEDOUT) {
    	return -EAGAIN;
    }
@@ -94,9 +102,14 @@ static ssize_t qb_ipc_shm_recv(struct qb_ipc_one_way *one_way,

static ssize_t qb_ipc_shm_peek(struct qb_ipc_one_way *one_way, void **data_out, int32_t ms_timeout)
 {
-	ssize_t res = qb_rb_chunk_peek(one_way->u.shm.rb,
-				       data_out,
-				       ms_timeout);
+	ssize_t res;
+
+	if (one_way->u.shm.rb == NULL) {
+		return -EIDRM;
+	}
+	res = qb_rb_chunk_peek(one_way->u.shm.rb,
+			       data_out,
+			       ms_timeout);
    if (res == -ETIMEDOUT) {
    	return -EAGAIN;
    }
@@ -105,7 +118,9 @@ static ssize_t qb_ipc_shm_peek(struct qb_ipc_one_way *one_way, void **data_out,

static void qb_ipc_shm_reclaim(struct qb_ipc_one_way *one_way)
 {
-	qb_rb_chunk_reclaim(one_way->u.shm.rb);
+	if (one_way->u.shm.rb != NULL) {
+		qb_rb_chunk_reclaim(one_way->u.shm.rb);
+	}
 }

static void qb_ipc_shm_fc_set(struct qb_ipc_one_way *one_way,
@@ -125,6 +140,9 @@ static int32_t qb_ipc_shm_fc_get(struct qb_ipc_one_way *one_way)

static ssize_t qb_ipc_shm_q_len_get(struct qb_ipc_one_way *one_way)
 {
+	if (one_way->u.shm.rb == NULL) {
+		return -EIDRM;
+	}
    return qb_rb_chunks_used(one_way->u.shm.rb);
 }

diff --git a/lib/ipcs.c b/lib/ipcs.c
index 1538d40..32ed22f 100644
--- a/lib/ipcs.c
+++ b/lib/ipcs.c
@@ -534,7 +534,7 @@ static ssize_t _request_q_len_get(struct qb_ipcs_connection *c)
    if (c->service->funcs.q_len_get) {
    	q_len = c->service->funcs.q_len_get(&c->request);
    	if (q_len < 0) {
-			q_len = 1;
+			return q_len;
    	}
    	q_len = QB_MIN(q_len, MAX_RECV_MSGS);
    	if (c->service->poll_priority == QB_LOOP_MED)
@@ -573,6 +573,7 @@ int32_t qb_ipcs_dispatch_connection_request(int32_t fd, int32_t revents,
    	return 0;
    }
    avail = _request_q_len_get(c);
+	res = avail; /* in case error */
    do {
    	res = _process_request_(c, IPC_REQUEST_TIMEOUT);
    	if (res > 0 || res == -ENOBUFS || res == -EINVAL) {