From owner-dev-commits-src-all@freebsd.org Sun Jul 18 00:36:57 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 A503B65F842; Sun, 18 Jul 2021 00:36:57 +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 4GS5dh6N6Tz4Rmv; Sun, 18 Jul 2021 00:36:56 +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 790371A69C; Sun, 18 Jul 2021 00:36:54 +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 16I0asqp049739; Sun, 18 Jul 2021 00:36:54 GMT (envelope-from git@gitrepo.freebsd.org) Received: (from git@localhost) by gitrepo.freebsd.org (8.16.1/8.16.1/Submit) id 16I0ass2049738; Sun, 18 Jul 2021 00:36:54 GMT (envelope-from git) Date: Sun, 18 Jul 2021 00:36:54 GMT Message-Id: <202107180036.16I0ass2049738@gitrepo.freebsd.org> To: src-committers@FreeBSD.org, dev-commits-src-all@FreeBSD.org, dev-commits-src-branches@FreeBSD.org From: "Bjoern A. Zeeb" Subject: git: d2c8c4d15a6e - stable/13 - LinuxKPI: fix sg_pcopy_from_buffer() MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8bit X-Git-Committer: bz X-Git-Repository: src X-Git-Refname: refs/heads/stable/13 X-Git-Reftype: branch X-Git-Commit: d2c8c4d15a6e65657b52b058b38d609e65202ad4 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, 18 Jul 2021 00:36:58 -0000 The branch stable/13 has been updated by bz: URL: https://cgit.FreeBSD.org/src/commit/?id=d2c8c4d15a6e65657b52b058b38d609e65202ad4 commit d2c8c4d15a6e65657b52b058b38d609e65202ad4 Author: Bjoern A. Zeeb AuthorDate: 2021-06-07 15:00:19 +0000 Commit: Bjoern A. Zeeb CommitDate: 2021-07-18 00:35:04 +0000 LinuxKPI: fix sg_pcopy_from_buffer() In sg_pcopy_from_buffer() is an error in that skip can underflow and lead to bogus page arithmetics which may lead to memory corruption or more likely panics. Once we found a s/g page to copy into there is nothing to skip anymore so simply set skip to 0. Sponsored by: The FreeBSD Foundation Reviewed by: hselasky Differential Revision: https://reviews.freebsd.org/D30676 (cherry picked from commit edfcdffefc1671b7688c8806ae1f59484954dcc7) --- sys/compat/linuxkpi/common/include/linux/scatterlist.h | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/sys/compat/linuxkpi/common/include/linux/scatterlist.h b/sys/compat/linuxkpi/common/include/linux/scatterlist.h index ebf0632f6f58..5e42876facd0 100644 --- a/sys/compat/linuxkpi/common/include/linux/scatterlist.h +++ b/sys/compat/linuxkpi/common/include/linux/scatterlist.h @@ -520,12 +520,13 @@ sg_pcopy_from_buffer(struct scatterlist *sgl, unsigned int nents, memcpy(p, b, len); sf_buf_free(sf); + /* We copied so nothing more to skip. */ + skip = 0; copied += len; /* Either we exactly filled the page, or we are done. */ buflen -= len; if (buflen == 0) break; - skip -= len; b += len; } sched_unpin();