From eeee05f35f014a8c068e0d29b18629cafbfdfc1d Mon Sep 17 00:00:00 2001 From: Mathieu Desnoyers Date: Fri, 13 Jan 2012 16:11:32 -0500 Subject: [PATCH] ust comm: Receive second FD even if 1st receive failed Ensures proper protocol behavior, because the sender expects the receiver to get the two file descriptors. Signed-off-by: Mathieu Desnoyers --- liblttng-ust-ctl/ustctl.c | 48 +++++++++++++++++++++++++++++---------- 1 file changed, 36 insertions(+), 12 deletions(-) diff --git a/liblttng-ust-ctl/ustctl.c b/liblttng-ust-ctl/ustctl.c index 8dce7878..fc7f57ca 100644 --- a/liblttng-ust-ctl/ustctl.c +++ b/liblttng-ust-ctl/ustctl.c @@ -135,7 +135,7 @@ int ustctl_open_metadata(int sock, int session_handle, struct ustcomm_ust_msg lum; struct ustcomm_ust_reply lur; struct lttng_ust_object_data *metadata_data; - int ret; + int ret, err = 0; metadata_data = malloc(sizeof(*metadata_data)); if (!metadata_data) @@ -166,13 +166,21 @@ int ustctl_open_metadata(int sock, int session_handle, /* get shm fd */ ret = ustcomm_recv_fd(sock); if (ret < 0) - goto error; - metadata_data->shm_fd = ret; + err = 1; + else + metadata_data->shm_fd = ret; + /* + * We need to get the second FD even if the first fails, because + * libust expects us to read the two FDs. + */ /* get wait fd */ ret = ustcomm_recv_fd(sock); if (ret < 0) + err = 1; + else + metadata_data->wait_fd = ret; + if (err) goto error; - metadata_data->wait_fd = ret; *_metadata_data = metadata_data; return 0; @@ -189,7 +197,7 @@ int ustctl_create_channel(int sock, int session_handle, struct ustcomm_ust_msg lum; struct ustcomm_ust_reply lur; struct lttng_ust_object_data *channel_data; - int ret; + int ret, err = 0; channel_data = malloc(sizeof(*channel_data)); if (!channel_data) @@ -220,13 +228,21 @@ int ustctl_create_channel(int sock, int session_handle, /* get shm fd */ ret = ustcomm_recv_fd(sock); if (ret < 0) - goto error; - channel_data->shm_fd = ret; + err = 1; + else + channel_data->shm_fd = ret; + /* + * We need to get the second FD even if the first fails, because + * libust expects us to read the two FDs. + */ /* get wait fd */ ret = ustcomm_recv_fd(sock); if (ret < 0) + err = 1; + else + channel_data->wait_fd = ret; + if (err) goto error; - channel_data->wait_fd = ret; *_channel_data = channel_data; return 0; @@ -247,7 +263,7 @@ int ustctl_create_stream(int sock, struct lttng_ust_object_data *channel_data, struct ustcomm_ust_msg lum; struct ustcomm_ust_reply lur; struct lttng_ust_object_data *stream_data; - int ret, fd; + int ret, fd, err = 0; stream_data = malloc(sizeof(*stream_data)); if (!stream_data) @@ -272,13 +288,21 @@ int ustctl_create_stream(int sock, struct lttng_ust_object_data *channel_data, /* get shm fd */ fd = ustcomm_recv_fd(sock); if (fd < 0) - goto error; - stream_data->shm_fd = fd; + err = 1; + else + stream_data->shm_fd = fd; + /* + * We need to get the second FD even if the first fails, because + * libust expects us to read the two FDs. + */ /* get wait fd */ fd = ustcomm_recv_fd(sock); if (fd < 0) + err = 1; + else + stream_data->wait_fd = fd; + if (err) goto error; - stream_data->wait_fd = fd; *_stream_data = stream_data; return ret; -- 2.34.1