From 7fa875b8e53c288d616234b9daf417b0650ce1cc Mon Sep 17 00:00:00 2001 From: Dylan Yudaken Date: Thu, 14 Jul 2022 04:02:56 -0700 Subject: net: copy from user before calling __copy_msghdr this is in preparation for multishot receive from io_uring, where it needs to have access to the original struct user_msghdr. functionally this should be a no-op. Acked-by: Paolo Abeni Signed-off-by: Dylan Yudaken Link: https://lore.kernel.org/r/20220714110258.1336200-2-dylany@fb.com Signed-off-by: Jens Axboe --- net/socket.c | 37 ++++++++++++++++--------------------- 1 file changed, 16 insertions(+), 21 deletions(-) (limited to 'net/socket.c') diff --git a/net/socket.c b/net/socket.c index 96300cdc0625..843545c21ec2 100644 --- a/net/socket.c +++ b/net/socket.c @@ -2358,25 +2358,20 @@ struct used_address { unsigned int name_len; }; -int __copy_msghdr_from_user(struct msghdr *kmsg, - struct user_msghdr __user *umsg, - struct sockaddr __user **save_addr, - struct iovec __user **uiov, size_t *nsegs) +int __copy_msghdr(struct msghdr *kmsg, + struct user_msghdr *msg, + struct sockaddr __user **save_addr) { - struct user_msghdr msg; ssize_t err; - if (copy_from_user(&msg, umsg, sizeof(*umsg))) - return -EFAULT; - kmsg->msg_control_is_user = true; kmsg->msg_get_inq = 0; - kmsg->msg_control_user = msg.msg_control; - kmsg->msg_controllen = msg.msg_controllen; - kmsg->msg_flags = msg.msg_flags; + kmsg->msg_control_user = msg->msg_control; + kmsg->msg_controllen = msg->msg_controllen; + kmsg->msg_flags = msg->msg_flags; - kmsg->msg_namelen = msg.msg_namelen; - if (!msg.msg_name) + kmsg->msg_namelen = msg->msg_namelen; + if (!msg->msg_name) kmsg->msg_namelen = 0; if (kmsg->msg_namelen < 0) @@ -2386,11 +2381,11 @@ int __copy_msghdr_from_user(struct msghdr *kmsg, kmsg->msg_namelen = sizeof(struct sockaddr_storage); if (save_addr) - *save_addr = msg.msg_name; + *save_addr = msg->msg_name; - if (msg.msg_name && kmsg->msg_namelen) { + if (msg->msg_name && kmsg->msg_namelen) { if (!save_addr) { - err = move_addr_to_kernel(msg.msg_name, + err = move_addr_to_kernel(msg->msg_name, kmsg->msg_namelen, kmsg->msg_name); if (err < 0) @@ -2401,12 +2396,10 @@ int __copy_msghdr_from_user(struct msghdr *kmsg, kmsg->msg_namelen = 0; } - if (msg.msg_iovlen > UIO_MAXIOV) + if (msg->msg_iovlen > UIO_MAXIOV) return -EMSGSIZE; kmsg->msg_iocb = NULL; - *uiov = msg.msg_iov; - *nsegs = msg.msg_iovlen; return 0; } @@ -2418,8 +2411,10 @@ static int copy_msghdr_from_user(struct msghdr *kmsg, struct user_msghdr msg; ssize_t err; - err = __copy_msghdr_from_user(kmsg, umsg, save_addr, &msg.msg_iov, - &msg.msg_iovlen); + if (copy_from_user(&msg, umsg, sizeof(*umsg))) + return -EFAULT; + + err = __copy_msghdr(kmsg, &msg, save_addr); if (err) return err; -- cgit