From owner-dev-commits-src-all@freebsd.org Sat Sep 18 14:42:13 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 432A9677E40; Sat, 18 Sep 2021 14:42:13 +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 4HBYSP1Dstz3lvf; Sat, 18 Sep 2021 14:42:13 +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 0A66E38CB; Sat, 18 Sep 2021 14:42:13 +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 18IEgCdL024465; Sat, 18 Sep 2021 14:42:12 GMT (envelope-from git@gitrepo.freebsd.org) Received: (from git@localhost) by gitrepo.freebsd.org (8.16.1/8.16.1/Submit) id 18IEgCqN024464; Sat, 18 Sep 2021 14:42:12 GMT (envelope-from git) Date: Sat, 18 Sep 2021 14:42:12 GMT Message-Id: <202109181442.18IEgCqN024464@gitrepo.freebsd.org> To: src-committers@FreeBSD.org, dev-commits-src-all@FreeBSD.org, dev-commits-src-main@FreeBSD.org From: Mark Johnston Subject: git: 50b07c1f7131 - main - unix: Fix a use-after-free in unp_drop() 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/main X-Git-Reftype: branch X-Git-Commit: 50b07c1f7131fd535bbe1b53a3a2e4dfcdcc2e51 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: Sat, 18 Sep 2021 14:42:13 -0000 The branch main has been updated by markj: URL: https://cgit.FreeBSD.org/src/commit/?id=50b07c1f7131fd535bbe1b53a3a2e4dfcdcc2e51 commit 50b07c1f7131fd535bbe1b53a3a2e4dfcdcc2e51 Author: Mark Johnston AuthorDate: 2021-09-18 14:38:39 +0000 Commit: Mark Johnston CommitDate: 2021-09-18 14:38:39 +0000 unix: Fix a use-after-free in unp_drop() We need to load the socket pointer after locking the PCB, otherwise the socket may have been detached and freed by the time that unp_drop() sets so_error. This previously went unnoticed as the socket zone was _NOFREE. Reported by: pho MFC after: 1 week --- sys/kern/uipc_usrreq.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/sys/kern/uipc_usrreq.c b/sys/kern/uipc_usrreq.c index 5add930bfa8e..0ee29143c731 100644 --- a/sys/kern/uipc_usrreq.c +++ b/sys/kern/uipc_usrreq.c @@ -1971,7 +1971,7 @@ unp_shutdown(struct unpcb *unp) static void unp_drop(struct unpcb *unp) { - struct socket *so = unp->unp_socket; + struct socket *so; struct unpcb *unp2; /* @@ -1981,6 +1981,7 @@ unp_drop(struct unpcb *unp) */ UNP_PCB_LOCK(unp); + so = unp->unp_socket; if (so) so->so_error = ECONNRESET; if ((unp2 = unp_pcb_lock_peer(unp)) != NULL) {