From mboxrd@z Thu Jan 1 00:00:00 1970 From: Maxime Coquelin Subject: Re: [PATCH v3 07/19] vhost: add number of fds to vhost-user messages and use it Date: Mon, 8 Oct 2018 14:56:16 +0200 Message-ID: References: <20181004081403.8039-1-maxime.coquelin@redhat.com> <20181004081403.8039-8-maxime.coquelin@redhat.com> <20181005095427eucas1p118e02435cf618d4f5306c734b423d0b1~arcEyNIT03167231672eucas1p1b@eucas1p1.samsung.com> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit Cc: dgilbert@redhat.com, stable@dpdk.org To: Ilya Maximets , dev@dpdk.org, tiwei.bie@intel.com, zhihong.wang@intel.com, jfreimann@redhat.com, nicknickolaev@gmail.com, bruce.richardson@intel.com, alejandro.lucero@netronome.com Return-path: In-Reply-To: <20181005095427eucas1p118e02435cf618d4f5306c734b423d0b1~arcEyNIT03167231672eucas1p1b@eucas1p1.samsung.com> Content-Language: en-US List-Id: DPDK patches and discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dev-bounces@dpdk.org Sender: "dev" On 10/05/2018 11:56 AM, Ilya Maximets wrote: > On 04.10.2018 11:13, Maxime Coquelin wrote: >> As soons as some anciliarry datai (fds) are received, it is copied >> without checking its length. >> >> This patch adds adds the number of fds received to the message, >> which is set in read_vhost_message(). >> >> This is preliminary work to support sending fds to Qemu. >> >> Signed-off-by: Dr. David Alan Gilbert >> Signed-off-by: Maxime Coquelin >> --- >> lib/librte_vhost/socket.c | 21 ++++++++++++++++----- >> lib/librte_vhost/vhost_user.c | 2 +- >> lib/librte_vhost/vhost_user.h | 4 +++- >> 3 files changed, 20 insertions(+), 7 deletions(-) >> >> diff --git a/lib/librte_vhost/socket.c b/lib/librte_vhost/socket.c >> index d63031747..c04d3d305 100644 >> --- a/lib/librte_vhost/socket.c >> +++ b/lib/librte_vhost/socket.c >> @@ -94,18 +94,23 @@ static struct vhost_user vhost_user = { >> .mutex = PTHREAD_MUTEX_INITIALIZER, >> }; >> >> -/* return bytes# of read on success or negative val on failure. */ >> +/* >> + * return bytes# of read on success or negative val on failure. Update fdnum >> + * with number of fds read. >> + */ >> int >> -read_fd_message(int sockfd, char *buf, int buflen, int *fds, int fd_num) >> +read_fd_message(int sockfd, char *buf, int buflen, int *fds, int max_fds, >> + int *fd_num) >> { >> struct iovec iov; >> struct msghdr msgh; >> - size_t fdsize = fd_num * sizeof(int); >> - char control[CMSG_SPACE(fdsize)]; >> + char control[CMSG_SPACE(max_fds * sizeof(int))]; >> struct cmsghdr *cmsg; >> int got_fds = 0; >> int ret; >> >> + *fd_num = 0; >> + >> memset(&msgh, 0, sizeof(msgh)); >> iov.iov_base = buf; >> iov.iov_len = buflen; >> @@ -131,13 +136,19 @@ read_fd_message(int sockfd, char *buf, int buflen, int *fds, int fd_num) >> if ((cmsg->cmsg_level == SOL_SOCKET) && >> (cmsg->cmsg_type == SCM_RIGHTS)) { >> got_fds = (cmsg->cmsg_len - CMSG_LEN(0)) / sizeof(int); >> + if (got_fds > max_fds) { >> + RTE_LOG(ERR, VHOST_CONFIG, >> + "Received msg contains more fds than supported\n"); >> + return -1; > > Looks like we'll leak all that file descriptors here. > I think, we need to get and close the valid ones anyway. Indeed. I fixed it as below in upcoming iteration: if (got_fds > max_fds) { RTE_LOG(ERR, VHOST_CONFIG, "Received msg contains more fds than supported\n"); tmp_fds = (int *)CMSG_DATA(cmsg); while (got_fds--) close(tmp_fds[got_fds]); return -1; } >> + } >> + *fd_num = got_fds; >> memcpy(fds, CMSG_DATA(cmsg), got_fds * sizeof(int)); >> break; >> } >> } >> >> /* Clear out unused file descriptors */ >> - while (got_fds < fd_num) >> + while (got_fds < max_fds) >> fds[got_fds++] = -1; >> >> return ret; >> diff --git a/lib/librte_vhost/vhost_user.c b/lib/librte_vhost/vhost_user.c >> index b6eae8dc5..ad69a267e 100644 >> --- a/lib/librte_vhost/vhost_user.c >> +++ b/lib/librte_vhost/vhost_user.c >> @@ -1518,7 +1518,7 @@ read_vhost_message(int sockfd, struct VhostUserMsg *msg) >> int ret; >> >> ret = read_fd_message(sockfd, (char *)msg, VHOST_USER_HDR_SIZE, >> - msg->fds, VHOST_MEMORY_MAX_NREGIONS); >> + msg->fds, VHOST_MEMORY_MAX_NREGIONS, &msg->fd_num); >> if (ret <= 0) >> return ret; >> >> diff --git a/lib/librte_vhost/vhost_user.h b/lib/librte_vhost/vhost_user.h >> index 42166adf2..dd0262f8f 100644 >> --- a/lib/librte_vhost/vhost_user.h >> +++ b/lib/librte_vhost/vhost_user.h >> @@ -132,6 +132,7 @@ typedef struct VhostUserMsg { >> VhostUserVringArea area; >> } payload; >> int fds[VHOST_MEMORY_MAX_NREGIONS]; >> + int fd_num; >> } __attribute((packed)) VhostUserMsg; >> >> #define VHOST_USER_HDR_SIZE offsetof(VhostUserMsg, payload.u64) >> @@ -146,7 +147,8 @@ int vhost_user_iotlb_miss(struct virtio_net *dev, uint64_t iova, uint8_t perm); >> int vhost_user_host_notifier_ctrl(int vid, bool enable); >> >> /* socket.c */ >> -int read_fd_message(int sockfd, char *buf, int buflen, int *fds, int fd_num); >> +int read_fd_message(int sockfd, char *buf, int buflen, int *fds, int max_fds, >> + int *fd_num); >> int send_fd_message(int sockfd, char *buf, int buflen, int *fds, int fd_num); >> >> #endif >>