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 42CD0377A92; Sat, 17 Oct 2026 16:36:02 +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=1792254963; cv=none; b=FEw2F/pu/6yDyqaAX5p2gu+khhkH9oLQLBtnmeQ/KgHlFVsGmyRPdZANrBhrGvfn6bjAWyhmLnDQGh3YFGxf7LW0cm78achLFcBI7UBAUpvaRMsXCpClS/+IWD9bMEz2IDSmZ9ktnhXzpUIJ5nBdSGkJUXXfaf7w9SOB/0jU3oc= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1792254963; c=relaxed/simple; bh=KLavV9dhZKSaFBMsdw+diUEe/xH6/ETSapbDempsvUQ=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=H/HFvNzExbsIyKf5/6uMP7wYZCvf/SSDTdgAHNBmxWD/q92a2TSDsExYtm80DgaPwcChOt5O/l6/odG9hkcjKryYQA1T7w9gMbQ7eT05Twn19bBhO07C42Yk1ynmLTWB/ZC5Bak+3RKOY9mYtuffMMoieNeTqAzHyiAoH+T8TZc= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=Zx0wLKDu; 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="Zx0wLKDu" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 9061F1F000C4; Sat, 17 Oct 2026 16:36:01 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1792254962; bh=INwejEWkOc3pnnyFS57XWYq6opZRTAI9Vl2sfmnr60E=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=Zx0wLKDuDrgxx9E3YcjVnz2IGTjBxf9m4ZIwKsGrJQ5PqFzIYdzIHpIx1FJ6c+iKz 8AtBr0zBKMNkFW2ZzpvohcAFuYSFVURlq7I+cM83bS0fQnp3PNa3rZBCfeZjBRNYfs j++Xf94bo+TAL3qd2r6gO2sycqbHJDRoIQMM4fuA= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Namjae Jeon , Sasha Levin Subject: [PATCH 6.12 620/869] ksmbd: safely discard unregistered deferred locks Date: Sat, 17 Oct 2026 17:57:41 +0200 Message-ID: <20261017160052.926957323@linuxfoundation.org> X-Mailer: git-send-email 2.56.0 In-Reply-To: <20261017160036.979869304@linuxfoundation.org> References: <20261017160036.979869304@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: Namjae Jeon [ Upstream commit 054bcca4cd9f00719b01f7108b51a2168fb94f15 ] When vfs_lock_file() defers a lock, smb2_lock() puts its ksmbd_lock on rollback_list before allocating and registering the asynchronous work. If either operation fails, rollback assumes that smb_lock->conn is initialized and dereferences NULL. The deferred file_lock also remains linked into the VFS blocked-lock state while it is freed. Keep the lock off rollback_list until async setup succeeds. On setup failures, explicitly unblock and wake the deferred lock before freeing it and its ksmbd wrapper. Signed-off-by: Namjae Jeon Signed-off-by: Sasha Levin --- fs/smb/server/smb2pdu.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/fs/smb/server/smb2pdu.c b/fs/smb/server/smb2pdu.c index b2d4c30571d6c..951d3c4f861c4 100644 --- a/fs/smb/server/smb2pdu.c +++ b/fs/smb/server/smb2pdu.c @@ -7772,11 +7772,12 @@ int smb2_lock(struct ksmbd_work *work) ksmbd_debug(SMB, "would have to wait for getting lock\n"); - list_add(&smb_lock->llist, &rollback_list); argv = kmalloc(sizeof(void *), KSMBD_DEFAULT_GFP); if (!argv) { err = -ENOMEM; + smb2_free_lock(flock); + kfree(smb_lock); goto out; } argv[0] = flock; @@ -7787,8 +7788,11 @@ int smb2_lock(struct ksmbd_work *work) if (rc) { kfree(argv); err = -ENOMEM; + smb2_free_lock(flock); + kfree(smb_lock); goto out; } + list_add(&smb_lock->llist, &rollback_list); spin_lock(&fp->f_lock); list_add(&work->fp_entry, &fp->blocked_works); spin_unlock(&fp->f_lock); -- 2.53.0