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 883803254BC for ; Thu, 16 Oct 2025 09:20:15 +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=1760606415; cv=none; b=iDs2SoNeTwC3l2L7BlS/jwThaMmikAhZsuc0sLswW7Q/Bvh4S5HlXG2Hvlx4ow/TATk9GZS+I1Hybt31f++YGYzjCfggxVs3KaDPYKIvt6dNFWmSAKQM22/hInisHlPdPydtwnEXrYH7lW2EIBOd+9+FkdwkMhAdR5a/cUc82LM= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1760606415; c=relaxed/simple; bh=rqNszabIvnN0qIabf2vwT7HApoPXkurPKPSv7iA/hnI=; h=Subject:To:Cc:From:Date:Message-ID:MIME-Version:Content-Type; b=jJu9IXvd6JkhFvwLrfPTJqpYvCGLjxdSe/tEM5f9Lu0/Mt3FKcO06f3LY3dR204oy9thJo3m4mftWtR8INSNJaSKQjeBPbOlJv5xaHNmWtDmwdljrgqiw9TLLSkz6CPgrnEDkSxOetBn4/pUZStnrTrOKsRbIDXzhT4QvvH3JBw= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=J0flvj3B; 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="J0flvj3B" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 0A5FAC4CEF9; Thu, 16 Oct 2025 09:20:14 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1760606415; bh=rqNszabIvnN0qIabf2vwT7HApoPXkurPKPSv7iA/hnI=; h=Subject:To:Cc:From:Date:From; b=J0flvj3BWVUIVBUdR7hUw+TCQQJvlR7Lx5G8VgKTaqIBPdI27z/bA4NB68s2KV8Bc OgCWtHjCpCqGaT93ygoUJ3Y0j1DcUuu8rbwJRDm79/CEZmQiG5jspKChzdHKtnpG9u tvBus0WnmEvd3YCWjjXy66Bz8CtUlxtRdhi5SXos= Subject: FAILED: patch "[PATCH] usb: gadget: f_ecm: Refactor bind path to use __free()" failed to apply to 5.15-stable tree To: khtsai@google.com,gregkh@linuxfoundation.org Cc: From: Date: Thu, 16 Oct 2025 11:20:01 +0200 Message-ID: <2025101601-reset-distill-2ff3@gregkh> Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=ANSI_X3.4-1968 Content-Transfer-Encoding: 8bit The patch below does not apply to the 5.15-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-5.15.y git checkout FETCH_HEAD git cherry-pick -x 42988380ac67c76bb9dff8f77d7ef3eefd50b7b5 # git commit -s git send-email --to '' --in-reply-to '2025101601-reset-distill-2ff3@gregkh' --subject-prefix 'PATCH 5.15.y' HEAD^.. Possible dependencies: thanks, greg k-h ------------------ original commit in Linus's tree ------------------ >From 42988380ac67c76bb9dff8f77d7ef3eefd50b7b5 Mon Sep 17 00:00:00 2001 From: Kuen-Han Tsai Date: Tue, 16 Sep 2025 16:21:36 +0800 Subject: [PATCH] usb: gadget: f_ecm: Refactor bind path to use __free() After an bind/unbind cycle, the ecm->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: da741b8c56d6 ("usb ethernet gadget: split CDC Ethernet function") Cc: stable@kernel.org Signed-off-by: Kuen-Han Tsai Link: https://lore.kernel.org/r/20250916-ready-v1-5-4997bf277548@google.com Signed-off-by: Greg Kroah-Hartman Link: https://lore.kernel.org/r/20250916-ready-v1-5-4997bf277548@google.com diff --git a/drivers/usb/gadget/function/f_ecm.c b/drivers/usb/gadget/function/f_ecm.c index 027226325039..675d2bc538a4 100644 --- a/drivers/usb/gadget/function/f_ecm.c +++ b/drivers/usb/gadget/function/f_ecm.c @@ -8,6 +8,7 @@ /* #define VERBOSE_DEBUG */ +#include #include #include #include @@ -15,6 +16,8 @@ #include #include +#include + #include "u_ether.h" #include "u_ether_configfs.h" #include "u_ecm.h" @@ -678,6 +681,7 @@ ecm_bind(struct usb_configuration *c, struct usb_function *f) struct usb_ep *ep; struct f_ecm_opts *ecm_opts; + struct usb_request *request __free(free_usb_request) = NULL; if (!can_support_ecm(cdev->gadget)) return -EINVAL; @@ -711,7 +715,7 @@ ecm_bind(struct usb_configuration *c, struct usb_function *f) /* allocate instance-specific interface IDs */ status = usb_interface_id(c, f); if (status < 0) - goto fail; + return status; ecm->ctrl_id = status; ecm_iad_descriptor.bFirstInterface = status; @@ -720,24 +724,22 @@ ecm_bind(struct usb_configuration *c, struct usb_function *f) status = usb_interface_id(c, f); if (status < 0) - goto fail; + return status; ecm->data_id = status; ecm_data_nop_intf.bInterfaceNumber = status; ecm_data_intf.bInterfaceNumber = status; ecm_union_desc.bSlaveInterface0 = status; - status = -ENODEV; - /* allocate instance-specific endpoints */ ep = usb_ep_autoconfig(cdev->gadget, &fs_ecm_in_desc); if (!ep) - goto fail; + return -ENODEV; ecm->port.in_ep = ep; ep = usb_ep_autoconfig(cdev->gadget, &fs_ecm_out_desc); if (!ep) - goto fail; + return -ENODEV; ecm->port.out_ep = ep; /* NOTE: a status/notification endpoint is *OPTIONAL* but we @@ -746,20 +748,18 @@ ecm_bind(struct usb_configuration *c, struct usb_function *f) */ ep = usb_ep_autoconfig(cdev->gadget, &fs_ecm_notify_desc); if (!ep) - goto fail; + return -ENODEV; ecm->notify = ep; - status = -ENOMEM; - /* allocate notification request and buffer */ - ecm->notify_req = usb_ep_alloc_request(ep, GFP_KERNEL); - if (!ecm->notify_req) - goto fail; - ecm->notify_req->buf = kmalloc(ECM_STATUS_BYTECOUNT, GFP_KERNEL); - if (!ecm->notify_req->buf) - goto fail; - ecm->notify_req->context = ecm; - ecm->notify_req->complete = ecm_notify_complete; + request = usb_ep_alloc_request(ep, GFP_KERNEL); + if (!request) + return -ENOMEM; + request->buf = kmalloc(ECM_STATUS_BYTECOUNT, GFP_KERNEL); + if (!request->buf) + return -ENOMEM; + request->context = ecm; + request->complete = ecm_notify_complete; /* support all relevant hardware speeds... we expect that when * hardware is dual speed, all bulk-capable endpoints work at @@ -778,7 +778,7 @@ ecm_bind(struct usb_configuration *c, struct usb_function *f) status = usb_assign_descriptors(f, ecm_fs_function, ecm_hs_function, ecm_ss_function, ecm_ss_function); if (status) - goto fail; + return status; /* NOTE: all that is done without knowing or caring about * the network link ... which is unavailable to this code @@ -788,20 +788,12 @@ ecm_bind(struct usb_configuration *c, struct usb_function *f) ecm->port.open = ecm_open; ecm->port.close = ecm_close; + ecm->notify_req = no_free_ptr(request); + DBG(cdev, "CDC Ethernet: IN/%s OUT/%s NOTIFY/%s\n", ecm->port.in_ep->name, ecm->port.out_ep->name, ecm->notify->name); return 0; - -fail: - if (ecm->notify_req) { - kfree(ecm->notify_req->buf); - usb_ep_free_request(ecm->notify, ecm->notify_req); - } - - ERROR(cdev, "%s: can't bind, err %d\n", f->name, status); - - return status; } static inline struct f_ecm_opts *to_f_ecm_opts(struct config_item *item)