From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from zeniv.linux.org.uk (zeniv.linux.org.uk [62.89.141.173]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 345A534A797; Mon, 1 Jun 2026 18:47:23 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=62.89.141.173 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1780339647; cv=none; b=q9kAuMkkiOlkiwiBOE9JTsbp6ixtxBK6SskkK22UfEQTHLdCCRThr0guGdgRhidB4tnHZPvYt/JCEDi8GR2N2gCfMWbbsfepgx6G3TzLlp7a2COkNdko7IcZkw2bnuY+z5OkpoR2l/MmBjSHziylJIU1qmO5tGja0p69WNmOM3o= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1780339647; c=relaxed/simple; bh=20T54J+jQNZmADsMBseHhaKW95Pi0I49+HpNkopXDLg=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=VQzdCkNRv0+NeszdXI/sE7DVJvg1+v7py2fCQYw451FAA13vwBubvLlLHglHDGFn1Ik5U/c6O2imkhlsnxlcxkauz33JEpB4NdsfUlbBcxOt80FrjzXY9WIaabIf3mZx8Ebf1p1VgDENs1GPJrhLjFSOl66jYVM2tlXD5pInMAo= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=zeniv.linux.org.uk; spf=none smtp.mailfrom=ftp.linux.org.uk; dkim=pass (2048-bit key) header.d=linux.org.uk header.i=@linux.org.uk header.b=tykIP5KY; arc=none smtp.client-ip=62.89.141.173 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=zeniv.linux.org.uk Authentication-Results: smtp.subspace.kernel.org; spf=none smtp.mailfrom=ftp.linux.org.uk Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=linux.org.uk header.i=@linux.org.uk header.b="tykIP5KY" DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=linux.org.uk; s=zeniv-20220401; h=Sender:In-Reply-To:Content-Type: MIME-Version:References:Message-ID:Subject:Cc:To:From:Date:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description; bh=ctY67JM/7uBpWvM3JS0gHoDy69jmoh0iHIjO+3IZLzg=; b=tykIP5KYQhl6VIUGWUMnd+bOl5 1j0tHikqu0mpGA3jGQbLV0AQ/AqwKhjWslyTGR//ulV4olwtqa+YKwqPNnNHmBXV3wFes96gw4ghb oIkdklRjnyf4u9KFmkpaIyrPFG4SH1FCy6N24On90Ek8Cwg0yFNnudynnOncXFnWxPsDASfFocYPD OwK8VFOdUsQexCj/kem0Sn5tsINcYUfFUX+wRrEvO9eMO+WYYoYl6C4MbFuuIJz46v0Bl0WtIbglk mt55Vd13rHZTxW6QSwFqPQXa4OchwYFs1oR3R7MCUZ+9akEKS/0zQ+/bHPUGA5aIEZSR3coj8YCoJ 3RPgNReQ==; Received: from viro by zeniv.linux.org.uk with local (Exim 4.99.2 #2 (Red Hat Linux)) id 1wU7fP-00000003g9c-0db1; Mon, 01 Jun 2026 18:47:16 +0000 Date: Mon, 1 Jun 2026 19:47:15 +0100 From: Al Viro To: Jeff Layton Cc: Chuck Lever , NeilBrown , Olga Kornievskaia , Dai Ngo , Tom Talpey , David Howells , Rick Macklem , Chris Mason , linux-nfs@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH 2/6] nfsd: release path refs on follow_down() error Message-ID: <20260601184715.GJ2636677@ZenIV> References: <20260531-nfsd-testing-v1-0-7bfa481b0540@kernel.org> <20260531-nfsd-testing-v1-2-7bfa481b0540@kernel.org> Precedence: bulk X-Mailing-List: linux-nfs@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20260531-nfsd-testing-v1-2-7bfa481b0540@kernel.org> Sender: Al Viro On Sun, May 31, 2026 at 08:06:59AM -0400, Jeff Layton wrote: > Fix by calling path_put(&path) before the goto out in the err < 0 > arm so the entry-time refs are released on all follow_down() error > returns. Might be better to unify all those path_put()... Something like this, perhaps? diff --git a/fs/nfsd/vfs.c b/fs/nfsd/vfs.c index eafdf7b7890f..bdcd78f49112 100644 --- a/fs/nfsd/vfs.c +++ b/fs/nfsd/vfs.c @@ -141,13 +141,13 @@ nfsd_cross_mnt(struct svc_rqst *rqstp, struct dentry **dpp, if (path.mnt == exp->ex_path.mnt && path.dentry == dentry && nfsd_mountpoint(dentry, exp) == 2) { /* This is only a mountpoint in some other namespace */ - path_put(&path); goto out; } exp2 = rqst_exp_get_by_name(rqstp, &path); if (IS_ERR(exp2)) { err = PTR_ERR(exp2); + exp2 = NULL; /* * We normally allow NFS clients to continue * "underneath" a mountpoint that is not exported. @@ -157,10 +157,7 @@ nfsd_cross_mnt(struct svc_rqst *rqstp, struct dentry **dpp, */ if (err == -ENOENT && !(exp->ex_flags & NFSEXP_V4ROOT)) err = 0; - path_put(&path); - goto out; - } - if (nfsd_v4client(rqstp) || + } else if (nfsd_v4client(rqstp) || (exp->ex_flags & NFSEXP_CROSSMOUNT) || EX_NOHIDE(exp2)) { /* successfully crossed mount point */ /* @@ -174,9 +171,10 @@ nfsd_cross_mnt(struct svc_rqst *rqstp, struct dentry **dpp, *expp = exp2; exp2 = exp; } - path_put(&path); - exp_put(exp2); out: + path_put(&path); + if (exp2) + exp_put(exp2); return err; }