From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (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 9DE225476DF for ; Wed, 9 Sep 2026 11:40:41 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788954042; cv=none; b=I0vaX+MnlKLR0itHKXRtByu0Mtcc0C5pmlSxbuX52U2gqxofsO52mDj+A7zEVeRSNmcvASo0azoAVZPB0g7bdSF/GNCMAvTNrNlaYxi74KYhYLw4xnbOZiu5hj+ug7Rglt0F8brw5ZWZmObjFbwVmw8SAnrjDpw+c9r+uCrDSsI= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788954042; c=relaxed/simple; bh=iMWgsiNhNtAy3CsjVgxRhkN5xtlJDMlDR99fEcKUTJA=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=a/xwn2DWW4pE7ZTVw61ErTbQDHPhynDRCKc4EZNd+p5ntgeHr9oh5irol+ahtTtgsOQVVqSx9YCWnsz0uwTHyLH3BH8Gu83EBso2lKzLqjtA43JBXLo1DzO9Z8gRrVChc3M36lXcDQegohf4RwHwNdYLWKn4grbDPUI3EvbGqDk= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=B8aiT3EQ; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="B8aiT3EQ" Received: by smtp.kernel.org (Postfix) with ESMTPSA id C55431F00ADB; Wed, 9 Sep 2026 11:40:40 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1788954041; bh=0wIdoZMcYE7tkpkzR1hyuCD7vjuKYe+UV4njeSanUo8=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=B8aiT3EQvm9FyeMTqiao6wN0B3KVV3aF9g07IFQoq+JnzJvAxAKRh07IeKIMbuEAo 30WGpKWBPt9mQEKuatbdJCIdqrCKmMPUuouBqx7letCmOyaq0iqLd2tsqmD07nfvY2 G/KmRaxFo1AC+i9PKhZMjCCv2+dQdnv0Cx/dmcIk+N/mtlhRD2wRcRrmrE62rnoIur gpFj5LBzCQoL7nJ1yK6NSSn4bwCpKGm5TV0KIX5kfQV35fcknEsDQu1MeT+cDkX0gm OjrhI/F4NiaTi9H+TjWRUpZPoQyjkkMRByu84gUXSfaCLqV2MvarORImCx8QggceLH r97KrOvdy7McQ== From: Sasha Levin To: stable@vger.kernel.org Cc: Shuangpeng Bai , Trond Myklebust , Sasha Levin Subject: [PATCH 5.15.y 2/2] lockd: fix NULL dereference on lockowner allocation failure Date: Wed, 9 Sep 2026 07:40:38 -0400 Message-ID: <20260909114038.1915471-2-sashal@kernel.org> X-Mailer: git-send-email 2.53.0 In-Reply-To: <20260909114038.1915471-1-sashal@kernel.org> References: <2026090351-huskiness-ecosphere-5753@gregkh> <20260909114038.1915471-1-sashal@kernel.org> Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit From: Shuangpeng Bai [ Upstream commit 4c7fc129db061c7daab841c4f3c342d894832362 ] nlmclnt_locks_init_private() installs NLM file lock operations even when nlmclnt_find_lockowner() fails to allocate a lockowner. nlmclnt_proc() then returns -ENOMEM, but the VFS still tears down the partially initialized file_lock and calls locks_release_private(). That invokes nlmclnt_locks_release_private(), which dereferences fl->fl_u.nfs_fl.owner and crashes because the owner was never installed. Clear fl_ops before attempting to initialize the NLM private state, and install the NLM lock operations only after a lockowner has been allocated successfully. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Cc: stable@vger.kernel.org Signed-off-by: Shuangpeng Bai Signed-off-by: Trond Myklebust Signed-off-by: Sasha Levin --- fs/lockd/clntproc.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/fs/lockd/clntproc.c b/fs/lockd/clntproc.c index a00729a9acd58..0e2494f9ed018 100644 --- a/fs/lockd/clntproc.c +++ b/fs/lockd/clntproc.c @@ -479,9 +479,12 @@ static const struct file_lock_operations nlmclnt_lock_ops = { static void nlmclnt_locks_init_private(struct file_lock *fl, struct nlm_host *host) { fl->fl_u.nfs_fl.state = 0; + fl->fl_ops = NULL; fl->fl_u.nfs_fl.owner = nlmclnt_find_lockowner(host, fl->c.flc_owner); INIT_LIST_HEAD(&fl->fl_u.nfs_fl.list); + if (!fl->fl_u.nfs_fl.owner) + return; fl->fl_ops = &nlmclnt_lock_ops; } -- 2.53.0