From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 15EDC27587E; Tue, 21 Oct 2025 20:00:02 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1761076802; cv=none; b=EZ+Plpuqbzpt/jz2GyNG9hJgOphTfpXPrLxtoIUhlJnKBipBuntDTWu8dnoQ7pcnHYJdZITihYHBlIMh7mpZ97rzR40LF1q1X39R6FWkEuifEYhV5LNSSJfP5KS3o2O5cBbFcamyoPDpzBUUxfG+Nj4uDLG6iSCjoj3J8SzpebU= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1761076802; c=relaxed/simple; bh=0uujzXi2Wyxvo2GY1tlWZ2hN3KblriNCyFI31hijZOI=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=Da3F2wqU2V6uFSuXMo8MUsFYiMac0nRbWSL8+WWsNDNga0NG9pAblrp17M/awsVE43m8A7HnHrYsJ1Dkb62COMBvC9VI7ZEGNm9cgHqpfWKbXo9Fgs6EAQ0E9G+GFEzXSZd4cbGIazGONfrD4VtcpYNXzHrL0aTZCrEQ/JJrj/E= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=lFg2HE+t; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="lFg2HE+t" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 6D1C7C4CEF1; Tue, 21 Oct 2025 20:00:01 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1761076801; bh=0uujzXi2Wyxvo2GY1tlWZ2hN3KblriNCyFI31hijZOI=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=lFg2HE+tbwKFhAI16YMvVvY9LETZG5h409Dee2YpRMSgx+lNq6sEw9ocqgf0lklwk R/A3k6GMWenuNCxrzvPhvTdRFx5aiSyNt3AfnW1ig/YJpu76TrF1wIld9PNT7p+xLB e87wf+jZQMq156/GzvjUJfkMbR0Jd8pErhJOrZM4= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, stable@kernel.org, Kuen-Han Tsai , Sasha Levin Subject: [PATCH 6.12 040/136] usb: gadget: f_rndis: Refactor bind path to use __free() Date: Tue, 21 Oct 2025 21:50:28 +0200 Message-ID: <20251021195036.944935213@linuxfoundation.org> X-Mailer: git-send-email 2.51.1 In-Reply-To: <20251021195035.953989698@linuxfoundation.org> References: <20251021195035.953989698@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: Kuen-Han Tsai [ Upstream commit 08228941436047bdcd35a612c1aec0912a29d8cd ] After an bind/unbind cycle, the rndis->notify_req is left stale. If a subsequent bind fails, the unified error label attempts to free this stale request, leading to a NULL pointer dereference when accessing ep->ops->free_request. Refactor the error handling in the bind path to use the __free() automatic cleanup mechanism. Fixes: 45fe3b8e5342 ("usb ethernet gadget: split RNDIS function") Cc: stable@kernel.org Signed-off-by: Kuen-Han Tsai Link: https://lore.kernel.org/r/20250916-ready-v1-6-4997bf277548@google.com Signed-off-by: Greg Kroah-Hartman Link: https://lore.kernel.org/r/20250916-ready-v1-6-4997bf277548@google.com Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman --- drivers/usb/gadget/function/f_rndis.c | 85 ++++++++++++++-------------------- 1 file changed, 35 insertions(+), 50 deletions(-) --- a/drivers/usb/gadget/function/f_rndis.c +++ b/drivers/usb/gadget/function/f_rndis.c @@ -19,6 +19,8 @@ #include +#include + #include "u_ether.h" #include "u_ether_configfs.h" #include "u_rndis.h" @@ -662,6 +664,8 @@ rndis_bind(struct usb_configuration *c, struct usb_ep *ep; struct f_rndis_opts *rndis_opts; + struct usb_os_desc_table *os_desc_table __free(kfree) = NULL; + struct usb_request *request __free(free_usb_request) = NULL; if (!can_support_rndis(c)) return -EINVAL; @@ -669,12 +673,9 @@ rndis_bind(struct usb_configuration *c, rndis_opts = container_of(f->fi, struct f_rndis_opts, func_inst); if (cdev->use_os_string) { - f->os_desc_table = kzalloc(sizeof(*f->os_desc_table), - GFP_KERNEL); - if (!f->os_desc_table) + os_desc_table = kzalloc(sizeof(*os_desc_table), GFP_KERNEL); + if (!os_desc_table) return -ENOMEM; - f->os_desc_n = 1; - f->os_desc_table[0].os_desc = &rndis_opts->rndis_os_desc; } rndis_iad_descriptor.bFunctionClass = rndis_opts->class; @@ -692,16 +693,14 @@ rndis_bind(struct usb_configuration *c, gether_set_gadget(rndis_opts->net, cdev->gadget); status = gether_register_netdev(rndis_opts->net); if (status) - goto fail; + return status; rndis_opts->bound = true; } us = usb_gstrings_attach(cdev, rndis_strings, ARRAY_SIZE(rndis_string_defs)); - if (IS_ERR(us)) { - status = PTR_ERR(us); - goto fail; - } + if (IS_ERR(us)) + return PTR_ERR(us); rndis_control_intf.iInterface = us[0].id; rndis_data_intf.iInterface = us[1].id; rndis_iad_descriptor.iFunction = us[2].id; @@ -709,36 +708,30 @@ rndis_bind(struct usb_configuration *c, /* allocate instance-specific interface IDs */ status = usb_interface_id(c, f); if (status < 0) - goto fail; + return status; rndis->ctrl_id = status; rndis_iad_descriptor.bFirstInterface = status; rndis_control_intf.bInterfaceNumber = status; rndis_union_desc.bMasterInterface0 = status; - if (cdev->use_os_string) - f->os_desc_table[0].if_id = - rndis_iad_descriptor.bFirstInterface; - status = usb_interface_id(c, f); if (status < 0) - goto fail; + return status; rndis->data_id = status; rndis_data_intf.bInterfaceNumber = status; rndis_union_desc.bSlaveInterface0 = status; - status = -ENODEV; - /* allocate instance-specific endpoints */ ep = usb_ep_autoconfig(cdev->gadget, &fs_in_desc); if (!ep) - goto fail; + return -ENODEV; rndis->port.in_ep = ep; ep = usb_ep_autoconfig(cdev->gadget, &fs_out_desc); if (!ep) - goto fail; + return -ENODEV; rndis->port.out_ep = ep; /* NOTE: a status/notification endpoint is, strictly speaking, @@ -747,21 +740,19 @@ rndis_bind(struct usb_configuration *c, */ ep = usb_ep_autoconfig(cdev->gadget, &fs_notify_desc); if (!ep) - goto fail; + return -ENODEV; rndis->notify = ep; - status = -ENOMEM; - /* allocate notification request and buffer */ - rndis->notify_req = usb_ep_alloc_request(ep, GFP_KERNEL); - if (!rndis->notify_req) - goto fail; - rndis->notify_req->buf = kmalloc(STATUS_BYTECOUNT, GFP_KERNEL); - if (!rndis->notify_req->buf) - goto fail; - rndis->notify_req->length = STATUS_BYTECOUNT; - rndis->notify_req->context = rndis; - rndis->notify_req->complete = rndis_response_complete; + request = usb_ep_alloc_request(ep, GFP_KERNEL); + if (!request) + return -ENOMEM; + request->buf = kmalloc(STATUS_BYTECOUNT, GFP_KERNEL); + if (!request->buf) + return -ENOMEM; + request->length = STATUS_BYTECOUNT; + request->context = rndis; + request->complete = rndis_response_complete; /* support all relevant hardware speeds... we expect that when * hardware is dual speed, all bulk-capable endpoints work at @@ -778,7 +769,7 @@ rndis_bind(struct usb_configuration *c, status = usb_assign_descriptors(f, eth_fs_function, eth_hs_function, eth_ss_function, eth_ss_function); if (status) - goto fail; + return status; rndis->port.open = rndis_open; rndis->port.close = rndis_close; @@ -789,9 +780,18 @@ rndis_bind(struct usb_configuration *c, if (rndis->manufacturer && rndis->vendorID && rndis_set_param_vendor(rndis->params, rndis->vendorID, rndis->manufacturer)) { - status = -EINVAL; - goto fail_free_descs; + usb_free_all_descriptors(f); + return -EINVAL; + } + + if (cdev->use_os_string) { + os_desc_table[0].os_desc = &rndis_opts->rndis_os_desc; + os_desc_table[0].if_id = rndis_iad_descriptor.bFirstInterface; + f->os_desc_table = no_free_ptr(os_desc_table); + f->os_desc_n = 1; + } + rndis->notify_req = no_free_ptr(request); /* NOTE: all that is done without knowing or caring about * the network link ... which is unavailable to this code @@ -802,21 +802,6 @@ rndis_bind(struct usb_configuration *c, rndis->port.in_ep->name, rndis->port.out_ep->name, rndis->notify->name); return 0; - -fail_free_descs: - usb_free_all_descriptors(f); -fail: - kfree(f->os_desc_table); - f->os_desc_n = 0; - - if (rndis->notify_req) { - kfree(rndis->notify_req->buf); - usb_ep_free_request(rndis->notify, rndis->notify_req); - } - - ERROR(cdev, "%s: can't bind, err %d\n", f->name, status); - - return status; } void rndis_borrow_net(struct usb_function_instance *f, struct net_device *net)