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 946B1530E05 for ; Wed, 9 Sep 2026 10:54:21 +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=1788951263; cv=none; b=K+Zu8eP83uor0byh4xRURGPwAAq8v+ou8gDIOpVU8nA75zn5XlCGsRvj7EwFY1rsLomQjyonIwzHCjImD0ihikf6yPAxuQPyeNHJ9ZUz7UujttwvdVapySF9CNk/9kWC6z7irunCupw4ir+q2lyz1K49Um3QfbuRUfpEvDKuShA= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788951263; c=relaxed/simple; bh=fsTTfnHQRtUYSvBRiiyTU/7kWFRmh7vaiicU9QQjtX8=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=HNIQRgQCUavAy0YRbCKDK0YZ06rUzqCNyPr0IualRz05KREv8hSl79OUjDmA58m9PpTfkWtspHLvdiB27+jmeAtywibl6211xPt5jEdDhA3x+6EF96B8b3KAdWw1QVi2ssL9a3DoUEB/uDc3CHQ+Omn8EbcgoJZ2La6irtTgC4Y= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=S8vbn6jX; 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="S8vbn6jX" Received: by smtp.kernel.org (Postfix) with ESMTPSA id F3C861F00AC4; Wed, 9 Sep 2026 10:54:20 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1788951261; bh=A9kxVVbuKbX4mfdY/DegnZSB7mF1OVpMqtIFpqh8pkw=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=S8vbn6jXbmDXWVQNw3fJWlh1VP8cK51EYTyU18Ub3rPd/QnTb7fFvD0XR+DfTfy0I y2ONTqiJ3dHpcMGCPB33MwD+AP5mbAkXUjjw3Gy1ch2vPgt2eBhUGp8JSesgNtNEMk T+LUc9OOylYEiejv4KCj2U9wj6SOyYUT3TBUjpEaemdaQv5oLq+u7ZQmLTiEfkhcXi msPuo7Hc6NO8DYxmBXXzKqJwtW92nR3G2+a2zUWRHndIgerpw/dmA1ZIPFT1ikdrgh +oB2cGMnPFO8NbHatlTsfKBex0vnot/J4fYtit328dztfYYCE4LE/HaJkHFxCRGmEQ vGud7GDQws7Vg== From: Sasha Levin To: stable@vger.kernel.org Cc: Shuangpeng Bai , Trond Myklebust , Sasha Levin Subject: [PATCH 6.6.y 2/2] lockd: fix NULL dereference on lockowner allocation failure Date: Wed, 9 Sep 2026 06:54:18 -0400 Message-ID: <20260909105418.1620378-2-sashal@kernel.org> X-Mailer: git-send-email 2.53.0 In-Reply-To: <20260909105418.1620378-1-sashal@kernel.org> References: <2026090350-anatomy-sublevel-d97c@gregkh> <20260909105418.1620378-1-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 d67af20386007..9f4fb49ba7704 100644 --- a/fs/lockd/clntproc.c +++ b/fs/lockd/clntproc.c @@ -486,9 +486,12 @@ 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