From owner-svn-src-stable-12@freebsd.org Tue May 14 20:41:25 2019 Return-Path: Delivered-To: svn-src-stable-12@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 4FDB115984F0; Tue, 14 May 2019 20:41:25 +0000 (UTC) (envelope-from trasz@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) server-signature RSA-PSS (4096 bits) client-signature RSA-PSS (4096 bits) client-digest SHA256) (Client CN "mxrelay.nyi.freebsd.org", Issuer "Let's Encrypt Authority X3" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id EB8C783DB3; Tue, 14 May 2019 20:41:24 +0000 (UTC) (envelope-from trasz@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 C5876262D8; Tue, 14 May 2019 20:41:24 +0000 (UTC) (envelope-from trasz@FreeBSD.org) Received: from repo.freebsd.org ([127.0.1.37]) by repo.freebsd.org (8.15.2/8.15.2) with ESMTP id x4EKfOEJ078704; Tue, 14 May 2019 20:41:24 GMT (envelope-from trasz@FreeBSD.org) Received: (from trasz@localhost) by repo.freebsd.org (8.15.2/8.15.2/Submit) id x4EKfO7v078703; Tue, 14 May 2019 20:41:24 GMT (envelope-from trasz@FreeBSD.org) Message-Id: <201905142041.x4EKfO7v078703@repo.freebsd.org> X-Authentication-Warning: repo.freebsd.org: trasz set sender to trasz@FreeBSD.org using -f From: Edward Tomasz Napierala Date: Tue, 14 May 2019 20:41:24 +0000 (UTC) To: src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-stable@freebsd.org, svn-src-stable-12@freebsd.org Subject: svn commit: r347579 - stable/12/sys/kern X-SVN-Group: stable-12 X-SVN-Commit-Author: trasz X-SVN-Commit-Paths: stable/12/sys/kern X-SVN-Commit-Revision: 347579 X-SVN-Commit-Repository: base MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-Rspamd-Queue-Id: EB8C783DB3 X-Spamd-Bar: -- Authentication-Results: mx1.freebsd.org X-Spamd-Result: default: False [-2.98 / 15.00]; local_wl_from(0.00)[FreeBSD.org]; NEURAL_HAM_MEDIUM(-1.00)[-0.998,0]; NEURAL_HAM_SHORT(-0.98)[-0.978,0]; ASN(0.00)[asn:11403, ipnet:2610:1c1:1::/48, country:US]; NEURAL_HAM_LONG(-1.00)[-1.000,0] X-BeenThere: svn-src-stable-12@freebsd.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: SVN commit messages for only the 12-stable src tree List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 14 May 2019 20:41:25 -0000 Author: trasz Date: Tue May 14 20:41:24 2019 New Revision: 347579 URL: https://svnweb.freebsd.org/changeset/base/347579 Log: MFC r346120: Use shared vnode locks for the ELF interpreter. Sponsored by: DARPA, AFRL Modified: stable/12/sys/kern/imgact_elf.c Directory Properties: stable/12/ (props changed) Modified: stable/12/sys/kern/imgact_elf.c ============================================================================== --- stable/12/sys/kern/imgact_elf.c Tue May 14 20:32:29 2019 (r347578) +++ stable/12/sys/kern/imgact_elf.c Tue May 14 20:41:24 2019 (r347579) @@ -717,7 +717,7 @@ __elfN(load_file)(struct proc *p, const char *file, u_ struct nameidata *nd; struct vattr *attr; struct image_params *imgp; - u_long rbase; + u_long flags, rbase; u_long base_addr = 0; int error; @@ -745,7 +745,10 @@ __elfN(load_file)(struct proc *p, const char *file, u_ imgp->object = NULL; imgp->execlabel = NULL; - NDINIT(nd, LOOKUP, LOCKLEAF | FOLLOW, UIO_SYSSPACE, file, curthread); + flags = FOLLOW | LOCKSHARED | LOCKLEAF; + +again: + NDINIT(nd, LOOKUP, flags, UIO_SYSSPACE, file, curthread); if ((error = namei(nd)) != 0) { nd->ni_vp = NULL; goto fail; @@ -760,15 +763,30 @@ __elfN(load_file)(struct proc *p, const char *file, u_ if (error) goto fail; + /* + * Also make certain that the interpreter stays the same, + * so set its VV_TEXT flag, too. Since this function is only + * used to load the interpreter, the VV_TEXT is almost always + * already set. + */ + if (VOP_IS_TEXT(nd->ni_vp) == 0) { + if (VOP_ISLOCKED(nd->ni_vp) != LK_EXCLUSIVE) { + /* + * LK_UPGRADE could have resulted in dropping + * the lock. Just try again from the start, + * this time with exclusive vnode lock. + */ + vput(nd->ni_vp); + flags &= ~LOCKSHARED; + goto again; + } + + VOP_SET_TEXT(nd->ni_vp); + } + error = exec_map_first_page(imgp); if (error) goto fail; - - /* - * Also make certain that the interpreter stays the same, so set - * its VV_TEXT flag, too. - */ - VOP_SET_TEXT(nd->ni_vp); imgp->object = nd->ni_vp->v_object;