From owner-dev-commits-src-all@freebsd.org Sun Sep 26 15:55:44 2021 Return-Path: Delivered-To: dev-commits-src-all@mailman.nyi.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mailman.nyi.freebsd.org (Postfix) with ESMTP id A528B67B5AC; Sun, 26 Sep 2021 15:55:44 +0000 (UTC) (envelope-from git@FreeBSD.org) Received: from mxrelay.nyi.freebsd.org (mxrelay.nyi.freebsd.org [IPv6:2610:1c1:1:606c::19:3]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256 client-signature RSA-PSS (4096 bits) client-digest SHA256) (Client CN "mxrelay.nyi.freebsd.org", Issuer "R3" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id 4HHVjX49wdz4dCk; Sun, 26 Sep 2021 15:55:44 +0000 (UTC) (envelope-from git@FreeBSD.org) Received: from gitrepo.freebsd.org (gitrepo.freebsd.org [IPv6:2610:1c1:1:6068::e6a:5]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (Client did not present a certificate) by mxrelay.nyi.freebsd.org (Postfix) with ESMTPS id 650EF2042D; Sun, 26 Sep 2021 15:55:44 +0000 (UTC) (envelope-from git@FreeBSD.org) Received: from gitrepo.freebsd.org ([127.0.1.44]) by gitrepo.freebsd.org (8.16.1/8.16.1) with ESMTP id 18QFtiw2008676; Sun, 26 Sep 2021 15:55:44 GMT (envelope-from git@gitrepo.freebsd.org) Received: (from git@localhost) by gitrepo.freebsd.org (8.16.1/8.16.1/Submit) id 18QFtipl008675; Sun, 26 Sep 2021 15:55:44 GMT (envelope-from git) Date: Sun, 26 Sep 2021 15:55:44 GMT Message-Id: <202109261555.18QFtipl008675@gitrepo.freebsd.org> To: src-committers@FreeBSD.org, dev-commits-src-all@FreeBSD.org, dev-commits-src-branches@FreeBSD.org From: Mark Johnston Subject: git: bcff2fdf8ee4 - stable/13 - freebsd32: Fix a double copyin in sendmsg() and recvmsg() MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8bit X-Git-Committer: markj X-Git-Repository: src X-Git-Refname: refs/heads/stable/13 X-Git-Reftype: branch X-Git-Commit: bcff2fdf8ee4b5053a5c7a7221879d2caf046b2b Auto-Submitted: auto-generated X-BeenThere: dev-commits-src-all@freebsd.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: Commit messages for all branches of the src repository List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sun, 26 Sep 2021 15:55:44 -0000 The branch stable/13 has been updated by markj: URL: https://cgit.FreeBSD.org/src/commit/?id=bcff2fdf8ee4b5053a5c7a7221879d2caf046b2b commit bcff2fdf8ee4b5053a5c7a7221879d2caf046b2b Author: Mark Johnston AuthorDate: 2021-09-19 17:45:09 +0000 Commit: Mark Johnston CommitDate: 2021-09-26 15:55:05 +0000 freebsd32: Fix a double copyin in sendmsg() and recvmsg() freebsd32_sendmsg() and freebsd32_recvmsg() both copyin the message header twice, once directly and once in freebsd32_copyinmsghdr(). The iovec length from the former is used when copying in msg_iov, but the rest of the kernel uses the iovec length from the latter. When kern_sendit() and kern_recvit() iterate over the iovec to compute the residual for I/O, they can therefore end up walking past the end of the copied in iovec, either resulting in a system call error, userspace memory corruption from uiomove() with invalid iovecs, or a kernel page fault if the copied-in iovec is followed by an unmapped KVA region. Reported by: syzbot+7cc64cd0c49605acd421@syzkaller.appspotmail.com Reviewed by: kib, emaste Sponsored by: The FreeBSD Foundation (cherry picked from commit fea1a98ead918b39280b586773a923e76194400b) --- sys/compat/freebsd32/freebsd32_misc.c | 14 +++----------- 1 file changed, 3 insertions(+), 11 deletions(-) diff --git a/sys/compat/freebsd32/freebsd32_misc.c b/sys/compat/freebsd32/freebsd32_misc.c index a4ae014dbe85..fd5ef9171982 100644 --- a/sys/compat/freebsd32/freebsd32_misc.c +++ b/sys/compat/freebsd32/freebsd32_misc.c @@ -1403,19 +1403,15 @@ int freebsd32_recvmsg(struct thread *td, struct freebsd32_recvmsg_args *uap) { struct msghdr msg; - struct msghdr32 m32; struct iovec *uiov, *iov; struct mbuf *control = NULL; struct mbuf **controlp; - int error; - error = copyin(uap->msg, &m32, sizeof(m32)); - if (error) - return (error); + error = freebsd32_copyinmsghdr(uap->msg, &msg); if (error) return (error); - error = freebsd32_copyiniov(PTRIN(m32.msg_iov), m32.msg_iovlen, &iov, + error = freebsd32_copyiniov((void *)msg.msg_iov, msg.msg_iovlen, &iov, EMSGSIZE); if (error) return (error); @@ -1548,19 +1544,15 @@ int freebsd32_sendmsg(struct thread *td, struct freebsd32_sendmsg_args *uap) { struct msghdr msg; - struct msghdr32 m32; struct iovec *iov; struct mbuf *control = NULL; struct sockaddr *to = NULL; int error; - error = copyin(uap->msg, &m32, sizeof(m32)); - if (error) - return (error); error = freebsd32_copyinmsghdr(uap->msg, &msg); if (error) return (error); - error = freebsd32_copyiniov(PTRIN(m32.msg_iov), m32.msg_iovlen, &iov, + error = freebsd32_copyiniov((void *)msg.msg_iov, msg.msg_iovlen, &iov, EMSGSIZE); if (error) return (error);