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 3695041D21E; Fri, 4 Sep 2026 06:16:24 +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=1788502586; cv=none; b=dRuYz+Phlt0EZeMapftGVBPr/uTCC7iOhe6xczFRzmejneC9is5JBsvXYuMsFBaGC3czaqTdr+mXY5lZUihUX3zVbOkvsW93ai5MotnAwCaocEXd2H0E0nCGCEDTA65aPrufpIK+XOscP+2dwzhpkg6q4mi8vKyyspcMhJGJWEo= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788502586; c=relaxed/simple; bh=PEoKl2w6zElZydyqJ7A7UK7M7Uu/xkQanlrjfbF7Ugk=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=EDUtxfl0it0Cc4zopo5uHuoA6KOMYJE7Bb5K+TnTMhCH2nxL7G67KxnvvTRoQbOrJWJ+cfkarkqdBI+1LDHvMIsXKkGfKLH3xcOKxEWkjrzmImoFMH91TQWKUSlWcaljwFHZErelcsD0uVPGI+5Z/ubkfOfheVdWc53RQZMc5vs= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=guxtykpk; 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="guxtykpk" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 4EB511F00A3D; Fri, 4 Sep 2026 06:16:24 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1788502584; bh=ZeElOof1kgpz8ea5lAqSqWorDsYeMFwia4EVukA0sLs=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=guxtykpkUTMgiP8C9I7FOyE924r5uGHDobhfCpZpg/m+rAUR/y/6QY7ppSXNdh/ls P0o+WELbLtgfXnE/kj/aTD1blSKpGCq1J90U7f0MRqoKGmTxS3RMbe1GvYyt3Af/Tv dMJLUUej8NSsvyTp+oj/V3NRb/wK9UEoh7fY5h1g= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Shuangpeng Bai , Trond Myklebust Subject: [PATCH 6.12 258/403] lockd: fix NULL dereference on lockowner allocation failure Date: Fri, 4 Sep 2026 07:01:01 +0200 Message-ID: <20260904045740.733022305@linuxfoundation.org> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260904045734.806166532@linuxfoundation.org> References: <20260904045734.806166532@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 6.12-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; }