From owner-dev-commits-src-all@freebsd.org Wed Jun 16 16:21:03 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 94A1E665383; Wed, 16 Jun 2021 16:21:03 +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 4G4r5q3bdLz4jX2; Wed, 16 Jun 2021 16:21:03 +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 649451E8FD; Wed, 16 Jun 2021 16:21:03 +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 15GGL3eY007089; Wed, 16 Jun 2021 16:21:03 GMT (envelope-from git@gitrepo.freebsd.org) Received: (from git@localhost) by gitrepo.freebsd.org (8.16.1/8.16.1/Submit) id 15GGL3BS007088; Wed, 16 Jun 2021 16:21:03 GMT (envelope-from git) Date: Wed, 16 Jun 2021 16:21:03 GMT Message-Id: <202106161621.15GGL3BS007088@gitrepo.freebsd.org> To: src-committers@FreeBSD.org, dev-commits-src-all@FreeBSD.org, dev-commits-src-main@FreeBSD.org From: Alex Richardson Subject: git: 1a2f06d0f290 - main - vis(3): avoid out-of-bounds stack buffer reads MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8bit X-Git-Committer: arichardson X-Git-Repository: src X-Git-Refname: refs/heads/main X-Git-Reftype: branch X-Git-Commit: 1a2f06d0f2905c9a18340b377cbbe772f2ca6844 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: Wed, 16 Jun 2021 16:21:03 -0000 The branch main has been updated by arichardson: URL: https://cgit.FreeBSD.org/src/commit/?id=1a2f06d0f2905c9a18340b377cbbe772f2ca6844 commit 1a2f06d0f2905c9a18340b377cbbe772f2ca6844 Author: Alex Richardson AuthorDate: 2021-06-16 15:27:13 +0000 Commit: Alex Richardson CommitDate: 2021-06-16 15:27:13 +0000 vis(3): avoid out-of-bounds stack buffer reads I found this while running kdump(1) on a CheriBSD system due to a capability length violation when printing the /etc/libmap.conf read() system call: it crashed immediately after printing the first line. Found by: CHERI Reviewed By: jhb MFC after: 3 days Differential Revision: https://reviews.freebsd.org/D30771 --- contrib/libc-vis/vis.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/contrib/libc-vis/vis.c b/contrib/libc-vis/vis.c index 21c07b70619d..c43186a44b51 100644 --- a/contrib/libc-vis/vis.c +++ b/contrib/libc-vis/vis.c @@ -465,7 +465,8 @@ istrsenvisx(char **mbdstp, size_t *dlen, const char *mbsrc, size_t mblength, while (mbslength > 0) { /* Convert one multibyte character to wchar_t. */ if (!cerr) - clen = mbrtowc(src, mbsrc, MB_LEN_MAX, &mbstate); + clen = mbrtowc(src, mbsrc, MIN(mbslength, MB_LEN_MAX), + &mbstate); if (cerr || clen < 0) { /* Conversion error, process as a byte instead. */ *src = (wint_t)(u_char)*mbsrc;