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 8EDDB18D636; Fri, 4 Sep 2026 05:56:41 +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=1788501402; cv=none; b=uTLFW1uOVDFXCTca9GOsJWJxVEJ80BO7txmTwpUt5TkP4oedaGe6iPKz6MUc9zFQbayTLGQHtTdir2ldBEEJdd5ANDrb39mvjGlkTcTGV+iep08XIESrq0Cr9hD58dwtSmzAds0qQ152fhQWKjQ830AeBcfQRo2acNCudxkyUD0= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788501402; c=relaxed/simple; bh=hkscTYuskfAYtfOzMeHWZ6aBpX6yjwgUj9IM1HKW+y8=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=TLgF7VC94/5XDPjLiPaDsLuzp3v9Tp+7QrcqKRCD0DIwfVL+EtedZuvqJhaeimwsDlwMGiL36KTjSpPGfvdM87yZLfnPS9E1EP8oAS9tBSeRbQ1yw5XVtP/OpSJ3dasRlY0vo5Rp1h6ux94w5t4zqjgHGJJ+4Tv56Ieh9e/X150= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=Z4VLyqYC; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="Z4VLyqYC" Received: by smtp.kernel.org (Postfix) with ESMTPSA id EA8A51F00A3D; Fri, 4 Sep 2026 05:56:40 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1788501401; bh=xQ3RZDokQEpACCbIFQ9ZbfKTz9I+Z0hp67jTrW13Elg=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=Z4VLyqYCyM9ZsQCK5GSnzrtKWQRGJEOXXUpq7MTnDVkp9Wej/GSylHeS7lmos3Paq HLhfqVI+14Kd3b0b64TOkg8385rO0h9a6ivmt0lNj0DbLc3IdK2hWpX3uYJu9uCpUY c+4DKC+O4gzae1LpcLckKDz050i1oTnUHOdbVl3Q= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Shuangpeng Bai , Trond Myklebust Subject: [PATCH 6.18 354/552] lockd: fix NULL dereference on lockowner allocation failure Date: Fri, 4 Sep 2026 06:58:31 +0200 Message-ID: <20260904045758.268055631@linuxfoundation.org> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260904045747.813364717@linuxfoundation.org> References: <20260904045747.813364717@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.18-stable review patch. If anyone has any objections, please let me know. ------------------ From: Shuangpeng Bai commit 4c7fc129db061c7daab841c4f3c342d894832362 upstream. 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: Greg Kroah-Hartman --- fs/lockd/clntproc.c | 3 +++ 1 file changed, 3 insertions(+) --- a/fs/lockd/clntproc.c +++ b/fs/lockd/clntproc.c @@ -487,9 +487,12 @@ static const struct file_lock_operations 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; }