From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 074BDE95A80 for ; Sun, 8 Oct 2023 19:43:27 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1344511AbjJHTnZ (ORCPT ); Sun, 8 Oct 2023 15:43:25 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:42638 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1344467AbjJHTnZ (ORCPT ); Sun, 8 Oct 2023 15:43:25 -0400 Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id CCF67AC for ; Sun, 8 Oct 2023 12:43:23 -0700 (PDT) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 1A92BC433C8; Sun, 8 Oct 2023 19:43:22 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1696794203; bh=WEHuFUOlDPEMe3VBMfxensXVWG1qJnbtRSD0gXnzwY0=; h=Subject:To:Cc:From:Date:From; b=DMncjc5GKUBUq4RmkOdvOtM2OcXcAmNNnQa0iQj2LmVWIXcF6i1wyiq/Q4P1ljetv 6v0KjOVbmoU37qhM0dm7IJi21LSdKlIi4ni6qWvJgOHlNe+dCb7bjJtTf5wlXbqMq1 DV3GWGMlRaWEy94B8wtEuzj4FVx4uosm7N/vxyF4= Subject: FAILED: patch "[PATCH] ksmbd: fix race condition from parallel smb2 lock requests" failed to apply to 6.1-stable tree To: linkinjeon@kernel.org, rootlab@huawei.com, stfrench@microsoft.com Cc: From: Date: Sun, 08 Oct 2023 21:43:07 +0200 Message-ID: <2023100807-alright-overeager-19bc@gregkh> MIME-Version: 1.0 Content-Type: text/plain; charset=ANSI_X3.4-1968 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org The patch below does not apply to the 6.1-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to . To reproduce the conflict and resubmit, you may use the following commands: git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-6.1.y git checkout FETCH_HEAD git cherry-pick -x 75ac9a3dd65f7eab4d12b0a0f744234b5300a491 # git commit -s git send-email --to '' --in-reply-to '2023100807-alright-overeager-19bc@gregkh' --subject-prefix 'PATCH 6.1.y' HEAD^.. Possible dependencies: 75ac9a3dd65f ("ksmbd: fix race condition from parallel smb2 lock requests") 38c8a9a52082 ("smb: move client and server files to common directory fs/smb") 3a9b557f44ea ("ksmbd: delete asynchronous work from list") d3ca9f7aeba7 ("ksmbd: fix possible memory leak in smb2_lock()") f8d6e7442aa7 ("ksmbd: fix typo, syncronous->synchronous") abdb1742a312 ("cifs: get rid of mount options string parsing") 9fd29a5bae6e ("cifs: use fs_context for automounts") thanks, greg k-h ------------------ original commit in Linus's tree ------------------ >From 75ac9a3dd65f7eab4d12b0a0f744234b5300a491 Mon Sep 17 00:00:00 2001 From: Namjae Jeon Date: Wed, 4 Oct 2023 18:31:03 +0900 Subject: [PATCH] ksmbd: fix race condition from parallel smb2 lock requests There is a race condition issue between parallel smb2 lock request. Time + Thread A | Thread A smb2_lock | smb2_lock | insert smb_lock to lock_list | spin_unlock(&work->conn->llist_lock) | | | spin_lock(&conn->llist_lock); | kfree(cmp_lock); | // UAF! | list_add(&smb_lock->llist, &rollback_list) + This patch swaps the line for adding the smb lock to the rollback list and adding the lock list of connection to fix the race issue. Reported-by: luosili Signed-off-by: Namjae Jeon Signed-off-by: Steve French diff --git a/fs/smb/server/smb2pdu.c b/fs/smb/server/smb2pdu.c index e774c9855f7f..fd6f05786ac2 100644 --- a/fs/smb/server/smb2pdu.c +++ b/fs/smb/server/smb2pdu.c @@ -7038,10 +7038,6 @@ int smb2_lock(struct ksmbd_work *work) ksmbd_debug(SMB, "would have to wait for getting lock\n"); - spin_lock(&work->conn->llist_lock); - list_add_tail(&smb_lock->clist, - &work->conn->lock_list); - spin_unlock(&work->conn->llist_lock); list_add(&smb_lock->llist, &rollback_list); argv = kmalloc(sizeof(void *), GFP_KERNEL); @@ -7072,9 +7068,6 @@ int smb2_lock(struct ksmbd_work *work) if (work->state != KSMBD_WORK_ACTIVE) { list_del(&smb_lock->llist); - spin_lock(&work->conn->llist_lock); - list_del(&smb_lock->clist); - spin_unlock(&work->conn->llist_lock); locks_free_lock(flock); if (work->state == KSMBD_WORK_CANCELLED) { @@ -7094,19 +7087,16 @@ int smb2_lock(struct ksmbd_work *work) } list_del(&smb_lock->llist); - spin_lock(&work->conn->llist_lock); - list_del(&smb_lock->clist); - spin_unlock(&work->conn->llist_lock); release_async_work(work); goto retry; } else if (!rc) { + list_add(&smb_lock->llist, &rollback_list); spin_lock(&work->conn->llist_lock); list_add_tail(&smb_lock->clist, &work->conn->lock_list); list_add_tail(&smb_lock->flist, &fp->lock_list); spin_unlock(&work->conn->llist_lock); - list_add(&smb_lock->llist, &rollback_list); ksmbd_debug(SMB, "successful in taking lock\n"); } else { goto out;