From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=100.103.45.18 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1794590196; b=A6NTt2TTIg4LiMnYdYO9Nte3Rj6We0cXJRj9KqG8esFKUMRTJxCEU1la8uXi3OByPiiV ifHFRVVgPL6XBamiJ7VQD8tdW8l0amrnfmV6ctoxJD9TqLQhpJl8TwgrZhQm5lHbV6mYJ 5eAO8Rz/A3VdYPfOWnY7LtgAQA5hXvkPHxHFyvoOsJpcK6kUceZp54NrGCAfW9kUpK98k h4G/dBUXNs3wTr0g/xS4iWXjxz4zBUBZW7MvQe3tjQXriFyHRnwIy4btgO2IJRG7lZo/j yWdtMXcRS3RSjiaW0hMBwfpMFbfmj2SSKG9+jCyZTts3NojBKZV2EQsK14/uVXX1v3g== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1794590196; h=Received:DKIM-Signature:From:To:Cc:Subject:Date:Message-ID:X-Mailer: In-Reply-To:References:User-Agent:X-stable:X-Patchwork-Hint: MIME-Version:Content-Transfer-Encoding; bh=EUIUNjf+XxYg7VlTiMKJGC3yptOeUZ6YuEeYf2iXdXI=; b=YNelzF5MN88SOP5WVtU1RsgLagR+hCNbNcAL+YH1b8OzdbgZa5TcPyB+8+pwwaX3+8BG pwIGOAcycw6vk/xDECpE4/uPdow2yeRyIg8oF1H2lGHCTNytLk71mehDapx6a9XdPOsep m3AR5j/RV5XdgYBk1AEzUwZnRHSfGpTorQLYlKJhJ/KlU2Oel0sgJUkhQVvAWXcrV66Cv TlKMICv7V82iGUIhnUX5YvLlRcJHwZLckcX/gEUTmC6I+Hx31fVact09n/tZ8oXcJLEJa lbjYXMzoU9sA5zYWBkqVMU9zjT+3EVzrF3JrwnFa9iJXLRZfTM0WF/k7skQ0yzhWM/Q== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass header.d=linuxfoundation.org header.i=@linuxfoundation.org header.a=rsa-sha256 header.s=korg header.b=n0Kmkjpt; arc=none smtp.remote-ip=100.103.45.18 Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 155C0606B36D; Fri, 13 Nov 2026 17:16:36 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.a=rsa-sha256 header.s=korg header.b=n0Kmkjpt Received: by smtp.kernel.org (Postfix) with ESMTPSA id BCDD21F000C5; Fri, 13 Nov 2026 17:16:35 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1794590195; bh=EUIUNjf+XxYg7VlTiMKJGC3yptOeUZ6YuEeYf2iXdXI=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=n0KmkjptTh9VU4Pn0nc3byWT+Q13y7RyzsneDUTm7UJHdXsMYlORlPNzLgwSDc3im E7Fbhe1duWP7RIH8hIHVFsilJj4aIIh5QaYpvUTS0kyDisGJk+ITZ60k0sVj1kgphz dkf+7uyN9/RieYlmPG2Gzx6JO0Wi++VDK6yZeSqU= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Yizhou Zhao , Yuxiang Yang , Ao Wang , Xuewei Feng , Qi Li , Ke Xu , Michael Grzeschik , Dominique Martinet , Sasha Levin Subject: [PATCH 6.18 185/686] net/9p/usbg: Fix use-after-free in disable_usb9pfs() Date: Fri, 13 Nov 2026 10:45:18 -0500 Message-ID: <20261113153827.273717622@linuxfoundation.org> X-Mailer: git-send-email 2.56.0 In-Reply-To: <20261113153820.902362109@linuxfoundation.org> References: <20261113153820.902362109@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore X-Mailing-List: patches@lists.linux.dev List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.18-stable review patch. If anyone has any objections, please let me know. ------------------ From: Yizhou Zhao [ Upstream commit 6f401e350939442b2ac905f7e5ac952e3802a5d8 ] disable_usb9pfs() frees the IN and OUT usb_request objects before it disables the corresponding endpoints. If either request is still queued, the later usb_ep_disable() call cancels the endpoint queue and the UDC driver can still access the already freed request. With dummy_hcd and KASAN, this is reproducible by queueing the OUT request and then disconnecting the configfs gadget: BUG: KASAN: slab-use-after-free in dummy_disable+0x2b4/0x300 Read of size 8 at addr ffff888009702400 by task sh/1 usb_ep_disable+0x8e/0x1f0 usb9pfs_func_unbind+0x193/0x350 gadget_dev_desc_UDC_store+0x135/0x280 dummy_free_request() also warns because the request is freed while its queue entry is still linked. Disable both endpoints before freeing the request objects. This lets usb_ep_disable() cancel any queued transfers and invoke the completion callback while the request storage is still valid. The request objects are then freed only after they have been removed from the endpoint queues. Fixes: a3be076dc174 ("net/9p/usbg: Add new usb gadget function transport") Cc: stable@vger.kernel.org Reported-by: Yizhou Zhao Reported-by: Yuxiang Yang Reported-by: Ao Wang Reported-by: Xuewei Feng Reported-by: Qi Li Reported-by: Ke Xu Assisted-by: GLM:GLM-5.1 Signed-off-by: Yizhou Zhao Acked-by: Michael Grzeschik Message-ID: <20260607130118.16579-1-zhaoyz24@mails.tsinghua.edu.cn> Signed-off-by: Dominique Martinet Signed-off-by: Sasha Levin --- net/9p/trans_usbg.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/net/9p/trans_usbg.c b/net/9p/trans_usbg.c index c682947dfb885..cd45d4a8597ad 100644 --- a/net/9p/trans_usbg.c +++ b/net/9p/trans_usbg.c @@ -277,6 +277,9 @@ static void disable_usb9pfs(struct f_usb9pfs *usb9pfs) struct usb_composite_dev *cdev = usb9pfs->function.config->cdev; + disable_ep(cdev, usb9pfs->in_ep); + disable_ep(cdev, usb9pfs->out_ep); + if (usb9pfs->in_req) { usb_ep_free_request(usb9pfs->in_ep, usb9pfs->in_req); usb9pfs->in_req = NULL; @@ -286,9 +289,6 @@ static void disable_usb9pfs(struct f_usb9pfs *usb9pfs) usb_ep_free_request(usb9pfs->out_ep, usb9pfs->out_req); usb9pfs->out_req = NULL; } - - disable_ep(cdev, usb9pfs->in_ep); - disable_ep(cdev, usb9pfs->out_ep); dev_dbg(&cdev->gadget->dev, "%s disabled\n", usb9pfs->function.name); } -- 2.53.0