From e1919a410049bf776e29f4da4d48e514476db455 Mon Sep 17 00:00:00 2001 From: Mathieu Desnoyers Date: Fri, 21 Feb 2014 13:00:59 -0500 Subject: [PATCH] Fix: dereference before null check Found by Coverity: CID 1090602 (#1 of 1): Dereference before null check (REVERSE_INULL) check_after_deref: Null-checking "stream" suggests that it may be null, but it has already been dereferenced on all paths leading to the check Signed-off-by: Mathieu Desnoyers --- liblttng-ust-ctl/ustctl.c | 42 ++++++++++++++++++++++++++------------- 1 file changed, 28 insertions(+), 14 deletions(-) diff --git a/liblttng-ust-ctl/ustctl.c b/liblttng-ust-ctl/ustctl.c index bc3ea9b1..854d8ae3 100644 --- a/liblttng-ust-ctl/ustctl.c +++ b/liblttng-ust-ctl/ustctl.c @@ -1523,11 +1523,13 @@ int ustctl_get_timestamp_begin(struct ustctl_consumer_stream *stream, uint64_t *timestamp_begin) { struct lttng_ust_client_lib_ring_buffer_client_cb *client_cb; - struct lttng_ust_lib_ring_buffer *buf = stream->buf; - struct lttng_ust_shm_handle *handle = stream->chan->chan->handle; + struct lttng_ust_lib_ring_buffer *buf; + struct lttng_ust_shm_handle *handle; if (!stream || !timestamp_begin) return -EINVAL; + buf = stream->buf; + handle = stream->chan->chan->handle; client_cb = get_client_cb(buf, handle); if (!client_cb) return -ENOSYS; @@ -1538,11 +1540,13 @@ int ustctl_get_timestamp_end(struct ustctl_consumer_stream *stream, uint64_t *timestamp_end) { struct lttng_ust_client_lib_ring_buffer_client_cb *client_cb; - struct lttng_ust_lib_ring_buffer *buf = stream->buf; - struct lttng_ust_shm_handle *handle = stream->chan->chan->handle; + struct lttng_ust_lib_ring_buffer *buf; + struct lttng_ust_shm_handle *handle; if (!stream || !timestamp_end) return -EINVAL; + buf = stream->buf; + handle = stream->chan->chan->handle; client_cb = get_client_cb(buf, handle); if (!client_cb) return -ENOSYS; @@ -1553,11 +1557,13 @@ int ustctl_get_events_discarded(struct ustctl_consumer_stream *stream, uint64_t *events_discarded) { struct lttng_ust_client_lib_ring_buffer_client_cb *client_cb; - struct lttng_ust_lib_ring_buffer *buf = stream->buf; - struct lttng_ust_shm_handle *handle = stream->chan->chan->handle; + struct lttng_ust_lib_ring_buffer *buf; + struct lttng_ust_shm_handle *handle; if (!stream || !events_discarded) return -EINVAL; + buf = stream->buf; + handle = stream->chan->chan->handle; client_cb = get_client_cb(buf, handle); if (!client_cb) return -ENOSYS; @@ -1568,11 +1574,13 @@ int ustctl_get_content_size(struct ustctl_consumer_stream *stream, uint64_t *content_size) { struct lttng_ust_client_lib_ring_buffer_client_cb *client_cb; - struct lttng_ust_lib_ring_buffer *buf = stream->buf; - struct lttng_ust_shm_handle *handle = stream->chan->chan->handle; + struct lttng_ust_lib_ring_buffer *buf; + struct lttng_ust_shm_handle *handle; if (!stream || !content_size) return -EINVAL; + buf = stream->buf; + handle = stream->chan->chan->handle; client_cb = get_client_cb(buf, handle); if (!client_cb) return -ENOSYS; @@ -1583,11 +1591,13 @@ int ustctl_get_packet_size(struct ustctl_consumer_stream *stream, uint64_t *packet_size) { struct lttng_ust_client_lib_ring_buffer_client_cb *client_cb; - struct lttng_ust_lib_ring_buffer *buf = stream->buf; - struct lttng_ust_shm_handle *handle = stream->chan->chan->handle; + struct lttng_ust_lib_ring_buffer *buf; + struct lttng_ust_shm_handle *handle; if (!stream || !packet_size) return -EINVAL; + buf = stream->buf; + handle = stream->chan->chan->handle; client_cb = get_client_cb(buf, handle); if (!client_cb) return -ENOSYS; @@ -1598,11 +1608,13 @@ int ustctl_get_stream_id(struct ustctl_consumer_stream *stream, uint64_t *stream_id) { struct lttng_ust_client_lib_ring_buffer_client_cb *client_cb; - struct lttng_ust_lib_ring_buffer *buf = stream->buf; - struct lttng_ust_shm_handle *handle = stream->chan->chan->handle; + struct lttng_ust_lib_ring_buffer *buf; + struct lttng_ust_shm_handle *handle; if (!stream || !stream_id) return -EINVAL; + buf = stream->buf; + handle = stream->chan->chan->handle; client_cb = get_client_cb(buf, handle); if (!client_cb) return -ENOSYS; @@ -1613,11 +1625,13 @@ int ustctl_get_current_timestamp(struct ustctl_consumer_stream *stream, uint64_t *ts) { struct lttng_ust_client_lib_ring_buffer_client_cb *client_cb; - struct lttng_ust_lib_ring_buffer *buf = stream->buf; - struct lttng_ust_shm_handle *handle = stream->chan->chan->handle; + struct lttng_ust_lib_ring_buffer *buf; + struct lttng_ust_shm_handle *handle; if (!stream || !ts) return -EINVAL; + buf = stream->buf; + handle = stream->chan->chan->handle; client_cb = get_client_cb(buf, handle); if (!client_cb || !client_cb->current_timestamp) return -ENOSYS; -- 2.34.1