From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mx1.redhat.com (mx1.redhat.com [209.132.183.28]) by dpdk.org (Postfix) with ESMTP id 641591B19F; Fri, 12 Oct 2018 10:46:03 +0200 (CEST) Received: from smtp.corp.redhat.com (int-mx07.intmail.prod.int.phx2.redhat.com [10.5.11.22]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 9ED9C3001910; Fri, 12 Oct 2018 08:46:02 +0000 (UTC) Received: from [10.36.112.48] (ovpn-112-48.ams2.redhat.com [10.36.112.48]) by smtp.corp.redhat.com (Postfix) with ESMTPS id C755B10018FF; Fri, 12 Oct 2018 08:45:53 +0000 (UTC) From: Maxime Coquelin 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, dgilbert@redhat.com Cc: stable@dpdk.org References: <20181011092432.22275-1-maxime.coquelin@redhat.com> <20181011092432.22275-8-maxime.coquelin@redhat.com> <20181011155709eucas1p20da3d82e3f74a0f8b8bd06eae4baa0c5~cmQddRjzg2527125271eucas1p2_@eucas1p2.samsung.com> <377e0ee1-562d-e5cb-e411-e041f8c60ba5@redhat.com> Message-ID: <7df5b8ea-6570-e2ab-1983-e74d316e530d@redhat.com> Date: Fri, 12 Oct 2018 10:45:51 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.9.1 MIME-Version: 1.0 In-Reply-To: <377e0ee1-562d-e5cb-e411-e041f8c60ba5@redhat.com> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 8bit X-Scanned-By: MIMEDefang 2.84 on 10.5.11.22 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.47]); Fri, 12 Oct 2018 08:46:02 +0000 (UTC) Subject: Re: [dpdk-dev] [PATCH v6 07/19] vhost: add number of fds to vhost-user messages and use it X-BeenThere: dev@dpdk.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: DPDK patches and discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 12 Oct 2018 08:46:03 -0000 On 10/12/2018 10:43 AM, Maxime Coquelin wrote: > > > On 10/11/2018 05:59 PM, Ilya Maximets wrote: >> On 11.10.2018 12:24, Maxime Coquelin wrote: >>> As soon as some ancillary data (fds) are received, it is copied >>> without checking its length. >>> >>> This patch 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     | 25 ++++++++++++++++++++----- >>>   lib/librte_vhost/vhost_user.c |  2 +- >>>   lib/librte_vhost/vhost_user.h |  4 +++- >>>   3 files changed, 24 insertions(+), 7 deletions(-) >>> >>> diff --git a/lib/librte_vhost/socket.c b/lib/librte_vhost/socket.c >>> index d63031747..3b0287a26 100644 >>> --- a/lib/librte_vhost/socket.c >>> +++ b/lib/librte_vhost/socket.c >>> @@ -94,18 +94,24 @@ 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 *tmp_fds; >>>       int ret; >>> +    *fd_num = 0; >>> + >>>       memset(&msgh, 0, sizeof(msgh)); >>>       iov.iov_base = buf; >>>       iov.iov_len  = buflen; >>> @@ -131,13 +137,22 @@ 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) { >> >> Hmm. I just noticed that 'msg_controllen' is set to receive >> not more than max_fds descriptors. So, this case should not >> be possible. We will receive MSG_CTRUNC and return before >> the loop. > > Maybe it is better to remove check for MSG_CTRUNC. s/remove/rework/ > IIUC, if MSG_CTRUNC happens, we may have to close anyway the ones > received. > > Do you agree? >>> +                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 83d3e6321..c1c5f35ff 100644 >>> --- a/lib/librte_vhost/vhost_user.c >>> +++ b/lib/librte_vhost/vhost_user.c >>> @@ -1509,7 +1509,7 @@ 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 62654f736..9a91d496b 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) >>> @@ -155,7 +156,8 @@ 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 >>>