From nobody Sun Nov 12 02:56:43 2023 X-Original-To: dev-commits-src-all@mlmmj.nyi.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mlmmj.nyi.freebsd.org (Postfix) with ESMTP id 4SScf32rcmz50fWh; Sun, 12 Nov 2023 02:56:43 +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 4SScf32QDjz3K6C; Sun, 12 Nov 2023 02:56:43 +0000 (UTC) (envelope-from git@FreeBSD.org) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=freebsd.org; s=dkim; t=1699757803; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding; bh=SKBetqd3552fAcxTNnrTy09SBf6tEVu0LcQWl2dseMg=; b=kPOAhuxBeEm5svj3qL2FUIeiP4ENw+uzCTds9HjVhMkjNLB7don1a48SF0zV7mLg8W6bRx OwXnFkJouDfpUjOWBQKndrT4whF6zV3gLR+4DaELA/YfXXv8fwTlx2OeRUCm4ecCJTWvTe fSNw3SmHZqoUlT8QyqAJCsoWlLfgZJSNp539XSj9IfHnOPyap0WMN68h4y5sUJ8XwUSry+ yUWkHtPN+9z6g3zuo7rR+wZAlTUqTey+f36KXkJKBud72OWFqZeRvhcIWadHblKpjt1FTB lC+jHWYlD22mCC12BTT2hddU+ZiDf+bEzfKpbu5DTmumc51pxA/DZmdKn5u34w== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=freebsd.org; s=dkim; t=1699757803; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding; bh=SKBetqd3552fAcxTNnrTy09SBf6tEVu0LcQWl2dseMg=; b=Dzqu8+HpQc2B7RPccnQzqTl0MyDoODITgDLQYqg5OPqAbIId30WdBrqeaqoZwjGeruTG0C JQkhA+UBpU1W8+egkX5zO1zsMiHhfnlHTx3Nl0riKQjJyOd6lut7Qp+84R7GIRj+jNE6f6 FKKpBTBj4Qwv1DQvyIz7YAPCVpH6/iwGbontWqTv3/O9NKEOjkPkfseEH3cdDaAV3duJYZ ea9eS0mvIrXZDeqIxdOR2yEOKdFJs9woxHPzyVMNXeYCFTEEkrnzKyrwBGN5XVrckW8xDM 2+rzaKze7cD0qPLx4nnQlz6NIBudsnA9oH5cnkOXo1BSWFk8zAoGtA2wTNqqpw== ARC-Authentication-Results: i=1; mx1.freebsd.org; none ARC-Seal: i=1; s=dkim; d=freebsd.org; t=1699757803; a=rsa-sha256; cv=none; b=NtWt06DfT94l16wdlWRlgqF2Q9zA/m+xWMJMS05daAFhfctuMDAx5H4HdanM1FJpHQ1My/ LntK0tOmz9Pr4xnGuDBDQVC50OVLf1Fpuiwki5TbvBLKmZpk6eCNlJanpwy26WGyug3gp1 cb0cRp3Dc/ZBQ8PfQq4KAPgwBkhd5OddYMQyn5p404gQ/cRzUW5/CuDWWeM+qMpI/q+8s6 GfmX6Wltpwsqvj2JgE3E2Kisn+lUs/3HxiHVDTJIrLs+GnosoVOpkoInnj1yuK3gwvdmYF jL02qitAk7LflB9UeuV3ZXL99PMYgGb6nSLDCyTUoP+C9C0gcKw2jX/MoQhQUw== 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 4SScf31TmQz15d7; Sun, 12 Nov 2023 02:56:43 +0000 (UTC) (envelope-from git@FreeBSD.org) Received: from gitrepo.freebsd.org ([127.0.1.44]) by gitrepo.freebsd.org (8.17.1/8.17.1) with ESMTP id 3AC2uh6c005774; Sun, 12 Nov 2023 02:56:43 GMT (envelope-from git@gitrepo.freebsd.org) Received: (from git@localhost) by gitrepo.freebsd.org (8.17.1/8.17.1/Submit) id 3AC2uhCX005771; Sun, 12 Nov 2023 02:56:43 GMT (envelope-from git) Date: Sun, 12 Nov 2023 02:56:43 GMT Message-Id: <202311120256.3AC2uhCX005771@gitrepo.freebsd.org> To: src-committers@FreeBSD.org, dev-commits-src-all@FreeBSD.org, dev-commits-src-branches@FreeBSD.org From: "Jason A. Harmening" Subject: git: 66b8f5484cfe - stable/14 - vfs_lookup_cross_mount(): restore previous do...while loop List-Id: Commit messages for all branches of the src repository List-Archive: https://lists.freebsd.org/archives/dev-commits-src-all List-Help: List-Post: List-Subscribe: List-Unsubscribe: Sender: owner-dev-commits-src-all@freebsd.org X-BeenThere: dev-commits-src-all@freebsd.org MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8bit X-Git-Committer: jah X-Git-Repository: src X-Git-Refname: refs/heads/stable/14 X-Git-Reftype: branch X-Git-Commit: 66b8f5484cfe0e37078b8b56355f2fa18b585f88 Auto-Submitted: auto-generated The branch stable/14 has been updated by jah: URL: https://cgit.FreeBSD.org/src/commit/?id=66b8f5484cfe0e37078b8b56355f2fa18b585f88 commit 66b8f5484cfe0e37078b8b56355f2fa18b585f88 Author: Jason A. Harmening AuthorDate: 2023-11-04 16:56:45 +0000 Commit: Jason A. Harmening CommitDate: 2023-11-12 02:38:26 +0000 vfs_lookup_cross_mount(): restore previous do...while loop When the cross-mount walking logic in vfs_lookup() was factored into a separate function, the main cross-mount traversal loop was changed from a do...while loop conditional on the current vnode having VIRF_MOUNTPOINT set to an unconditional for(;;) loop. For the unionfs 'crosslock' case in which the vnode may be re-locked, this meant that continuing the loop upon finding inconsistent v_mountedhere state would no longer branch to a check that the vnode is in fact still a mountpoint. This would in turn lead to over- iteration and, for INVARIANTS builds, a failed assert on the next iteration. Fix this by restoring the previous loop behavior. Reported by: pho Tested by: pho Fixes: 80bd5ef0702562c546fa1717e8fe221058974eac (cherry picked from commit 586fed0b03561558644eccc37f824c7110500182) --- sys/kern/vfs_lookup.c | 12 ++++++++---- 1 file changed, 8 insertions(+), 4 deletions(-) diff --git a/sys/kern/vfs_lookup.c b/sys/kern/vfs_lookup.c index d75351c34314..922adda33b94 100644 --- a/sys/kern/vfs_lookup.c +++ b/sys/kern/vfs_lookup.c @@ -882,7 +882,7 @@ vfs_lookup_cross_mount(struct nameidata *ndp) * The vnode has been mounted on, find the root of the mounted * filesystem. */ - for (;;) { + do { mp = dp->v_mountedhere; ASSERT_VOP_LOCKED(dp, __func__); VNPASS((vn_irflag_read(dp) & VIRF_MOUNTPOINT) != 0 && mp != NULL, dp); @@ -915,6 +915,12 @@ vfs_lookup_cross_mount(struct nameidata *ndp) break; } if (dp->v_mountedhere != mp) { + /* + * Note that we rely on the + * VIRF_MOUNTPOINT loop condition to + * ensure we stop iterating if dp is + * no longer a mountpoint at all. + */ continue; } } else @@ -939,9 +945,7 @@ vfs_lookup_cross_mount(struct nameidata *ndp) if (error != 0) break; ndp->ni_vp = dp = tdp; - if ((vn_irflag_read(dp) & VIRF_MOUNTPOINT) == 0) - break; - } + } while ((vn_irflag_read(dp) & VIRF_MOUNTPOINT) != 0); return (error); }