This is a note to let you know that I've just added the patch titled
usb: gadget: f_fs: Ensure ep0req is dequeued before free_request
to the 5.4-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
usb-gadget-f_fs-ensure-ep0req-is-dequeued-before-fre.patch
and it can be found in the queue-5.4 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit 23d70b688159117489387d782059899643abb829
Author: Udipto Goswami <quic_ugoswami@xxxxxxxxxxx>
Date: Thu Dec 15 10:59:06 2022 +0530
usb: gadget: f_fs: Ensure ep0req is dequeued before free_request
[ Upstream commit ce405d561b020e5a46340eb5146805a625dcacee ]
As per the documentation, function usb_ep_free_request guarantees
the request will not be queued or no longer be re-queued (or
otherwise used). However, with the current implementation it
doesn't make sure that the request in ep0 isn't reused.
Fix this by dequeuing the ep0req on functionfs_unbind before
freeing the request to align with the definition.
Fixes: ddf8abd25994 ("USB: f_fs: the FunctionFS driver")
Signed-off-by: Udipto Goswami <quic_ugoswami@xxxxxxxxxxx>
Tested-by: Krishna Kurapati <quic_kriskura@xxxxxxxxxxx>
Link: https://lore.kernel.org/r/20221215052906.8993-3-quic_ugoswami@xxxxxxxxxxx
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/drivers/usb/gadget/function/f_fs.c b/drivers/usb/gadget/function/f_fs.c
index 3b7323233b39..431ab6d07497 100644
--- a/drivers/usb/gadget/function/f_fs.c
+++ b/drivers/usb/gadget/function/f_fs.c
@@ -1903,6 +1903,8 @@ static void functionfs_unbind(struct ffs_data *ffs)
ENTER();
if (!WARN_ON(!ffs->gadget)) {
+ /* dequeue before freeing ep0req */
+ usb_ep_dequeue(ffs->gadget->ep0, ffs->ep0req);
mutex_lock(&ffs->mutex);
usb_ep_free_request(ffs->gadget->ep0, ffs->ep0req);
ffs->ep0req = NULL;
