From owner-svn-src-stable-12@freebsd.org Sun May 19 09:24:52 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 AF74615A8CDE; Sun, 19 May 2019 09:24:52 +0000 (UTC) (envelope-from kib@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 520D086563; Sun, 19 May 2019 09:24:52 +0000 (UTC) (envelope-from kib@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 2715951F1; Sun, 19 May 2019 09:24:52 +0000 (UTC) (envelope-from kib@FreeBSD.org) Received: from repo.freebsd.org ([127.0.1.37]) by repo.freebsd.org (8.15.2/8.15.2) with ESMTP id x4J9OqPH041749; Sun, 19 May 2019 09:24:52 GMT (envelope-from kib@FreeBSD.org) Received: (from kib@localhost) by repo.freebsd.org (8.15.2/8.15.2/Submit) id x4J9OqQp041748; Sun, 19 May 2019 09:24:52 GMT (envelope-from kib@FreeBSD.org) Message-Id: <201905190924.x4J9OqQp041748@repo.freebsd.org> X-Authentication-Warning: repo.freebsd.org: kib set sender to kib@FreeBSD.org using -f From: Konstantin Belousov Date: Sun, 19 May 2019 09:24:52 +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: r347970 - stable/12/sys/kern X-SVN-Group: stable-12 X-SVN-Commit-Author: kib X-SVN-Commit-Paths: stable/12/sys/kern X-SVN-Commit-Revision: 347970 X-SVN-Commit-Repository: base MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-Rspamd-Queue-Id: 520D086563 X-Spamd-Bar: -- Authentication-Results: mx1.freebsd.org X-Spamd-Result: default: False [-2.95 / 15.00]; local_wl_from(0.00)[FreeBSD.org]; NEURAL_HAM_MEDIUM(-1.00)[-0.999,0]; NEURAL_HAM_LONG(-1.00)[-1.000,0]; NEURAL_HAM_SHORT(-0.95)[-0.953,0]; ASN(0.00)[asn:11403, ipnet:2610:1c1:1::/48, country:US] 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: Sun, 19 May 2019 09:24:52 -0000 Author: kib Date: Sun May 19 09:24:51 2019 New Revision: 347970 URL: https://svnweb.freebsd.org/changeset/base/347970 Log: MFC r347690, r347946: imgact_elf.c: Add comment explaining the malloc/VOP_UNLOCK() dance from r347148. 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 Sun May 19 09:23:20 2019 (r347969) +++ stable/12/sys/kern/imgact_elf.c Sun May 19 09:24:51 2019 (r347970) @@ -958,12 +958,22 @@ __elfN(get_interp)(struct image_params *imgp, const El interp_name_len = phdr->p_filesz; if (phdr->p_offset > PAGE_SIZE || interp_name_len > PAGE_SIZE - phdr->p_offset) { + /* + * The vnode lock might be needed by the pagedaemon to + * clean pages owned by the vnode. Do not allow sleep + * waiting for memory with the vnode locked, instead + * try non-sleepable allocation first, and if it + * fails, go to the slow path were we drop the lock + * and do M_WAITOK. A text reference prevents + * modifications to the vnode content. + */ interp = malloc(interp_name_len + 1, M_TEMP, M_NOWAIT); if (interp == NULL) { VOP_UNLOCK(imgp->vp, 0); interp = malloc(interp_name_len + 1, M_TEMP, M_WAITOK); vn_lock(imgp->vp, LK_EXCLUSIVE | LK_RETRY); } + error = vn_rdwr(UIO_READ, imgp->vp, interp, interp_name_len, phdr->p_offset, UIO_SYSSPACE, IO_NODELOCKED, td->td_ucred,