From owner-svn-src-all@freebsd.org Fri May 25 07:29:53 2018 Return-Path: Delivered-To: svn-src-all@mailman.ysv.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mailman.ysv.freebsd.org (Postfix) with ESMTP id B949CF74F5C; Fri, 25 May 2018 07:29:53 +0000 (UTC) (envelope-from avg@FreeBSD.org) Received: from mxrelay.nyi.freebsd.org (mxrelay.nyi.freebsd.org [IPv6:2610:1c1:1:606c::19:3]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client CN "mxrelay.nyi.freebsd.org", Issuer "Let's Encrypt Authority X3" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id 570297630D; Fri, 25 May 2018 07:29:53 +0000 (UTC) (envelope-from avg@FreeBSD.org) Received: from repo.freebsd.org (repo.freebsd.org [IPv6:2610:1c1:1:6068::e6a:0]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client did not present a certificate) by mxrelay.nyi.freebsd.org (Postfix) with ESMTPS id 2BB7D1DC64; Fri, 25 May 2018 07:29:53 +0000 (UTC) (envelope-from avg@FreeBSD.org) Received: from repo.freebsd.org ([127.0.1.37]) by repo.freebsd.org (8.15.2/8.15.2) with ESMTP id w4P7Tq5x021380; Fri, 25 May 2018 07:29:52 GMT (envelope-from avg@FreeBSD.org) Received: (from avg@localhost) by repo.freebsd.org (8.15.2/8.15.2/Submit) id w4P7TqGY021379; Fri, 25 May 2018 07:29:52 GMT (envelope-from avg@FreeBSD.org) Message-Id: <201805250729.w4P7TqGY021379@repo.freebsd.org> X-Authentication-Warning: repo.freebsd.org: avg set sender to avg@FreeBSD.org using -f From: Andriy Gapon Date: Fri, 25 May 2018 07:29:52 +0000 (UTC) To: src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-head@freebsd.org Subject: svn commit: r334203 - head/sys/cddl/contrib/opensolaris/uts/common/fs/zfs X-SVN-Group: head X-SVN-Commit-Author: avg X-SVN-Commit-Paths: head/sys/cddl/contrib/opensolaris/uts/common/fs/zfs X-SVN-Commit-Revision: 334203 X-SVN-Commit-Repository: base MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-BeenThere: svn-src-all@freebsd.org X-Mailman-Version: 2.1.26 Precedence: list List-Id: "SVN commit messages for the entire src tree \(except for " user" and " projects" \)" List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 25 May 2018 07:29:54 -0000 Author: avg Date: Fri May 25 07:29:52 2018 New Revision: 334203 URL: https://svnweb.freebsd.org/changeset/base/334203 Log: fix zfs_getpages crash when called from sendfile, followup to r329363 It turns out that sendfile_swapin() has an optimization where it may insert pointers to bogus_page into the page array that it passes to VOP_GETPAGES. That happens to work with buffer cache, because it extensively uses bogus_page internally, so it has the necessary checks. However, ZFS did not expect bogus_page as VOP_GETPAGES(9) does not document such a (ab)use of bogus_page. So, this commit adds checks and handling of bogus_page. I expect that use of bogus_page with VOP_GETPAGES will get documented sooner rather than later. Reported by: Andrew Reilly , delphij Tested by: Andrew Reilly Requested by: many MFC after: 1 week Modified: head/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/dmu.c Modified: head/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/dmu.c ============================================================================== --- head/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/dmu.c Fri May 25 06:26:07 2018 (r334202) +++ head/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/dmu.c Fri May 25 07:29:52 2018 (r334203) @@ -1732,17 +1732,21 @@ dmu_read_pages(objset_t *os, uint64_t object, vm_page_ for (mi = 0, di = 0; mi < count && di < numbufs; ) { if (pgoff == 0) { m = ma[mi]; - vm_page_assert_xbusied(m); - ASSERT(m->valid == 0); - ASSERT(m->dirty == 0); - ASSERT(!pmap_page_is_mapped(m)); - va = zfs_map_page(m, &sf); + if (m != bogus_page) { + vm_page_assert_xbusied(m); + ASSERT(m->valid == 0); + ASSERT(m->dirty == 0); + ASSERT(!pmap_page_is_mapped(m)); + va = zfs_map_page(m, &sf); + } } if (bufoff == 0) db = dbp[di]; - ASSERT3U(IDX_TO_OFF(m->pindex) + pgoff, ==, - db->db_offset + bufoff); + if (m != bogus_page) { + ASSERT3U(IDX_TO_OFF(m->pindex) + pgoff, ==, + db->db_offset + bufoff); + } /* * We do not need to clamp the copy size by the file @@ -1750,13 +1754,16 @@ dmu_read_pages(objset_t *os, uint64_t object, vm_page_ * end of file anyway. */ tocpy = MIN(db->db_size - bufoff, PAGESIZE - pgoff); - bcopy((char *)db->db_data + bufoff, va + pgoff, tocpy); + if (m != bogus_page) + bcopy((char *)db->db_data + bufoff, va + pgoff, tocpy); pgoff += tocpy; ASSERT(pgoff <= PAGESIZE); if (pgoff == PAGESIZE) { - zfs_unmap_page(sf); - m->valid = VM_PAGE_BITS_ALL; + if (m != bogus_page) { + zfs_unmap_page(sf); + m->valid = VM_PAGE_BITS_ALL; + } ASSERT(mi < count); mi++; pgoff = 0; @@ -1801,6 +1808,7 @@ dmu_read_pages(objset_t *os, uint64_t object, vm_page_ } #endif if (pgoff != 0) { + ASSERT(m != bogus_page); bzero(va + pgoff, PAGESIZE - pgoff); zfs_unmap_page(sf); m->valid = VM_PAGE_BITS_ALL;