This is a note to let you know that I've just added the patch titled
usb: musb: Fix musb_gadget.c rxstate overflow bug
to the 4.9-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-musb-fix-musb_gadget.c-rxstate-overflow-bug.patch
and it can be found in the queue-4.9 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit 89ce6f83350f1e25e68e44734ffeacd6056a38ab
Author: Robin Guo <guoweibin@xxxxxxxxxx>
Date: Tue Sep 6 10:21:19 2022 +0800
usb: musb: Fix musb_gadget.c rxstate overflow bug
[ Upstream commit eea4c860c3b366369eff0489d94ee4f0571d467d ]
The usb function device call musb_gadget_queue() adds the passed
request to musb_ep::req_list,If the (request->length > musb_ep->packet_sz)
and (is_buffer_mapped(req) return false),the rxstate() will copy all data
in fifo to request->buf which may cause request->buf out of bounds.
Fix it by add the length check :
fifocnt = min_t(unsigned, request->length - request->actual, fifocnt);
Signed-off-by: Robin Guo <guoweibin@xxxxxxxxxx>
Link: https://lore.kernel.org/r/20220906102119.1b071d07a8391ff115e6d1ef@xxxxxxxxxx
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/drivers/usb/musb/musb_gadget.c b/drivers/usb/musb/musb_gadget.c
index 8eb3a291ca9d..02ec84ce5ab9 100644
--- a/drivers/usb/musb/musb_gadget.c
+++ b/drivers/usb/musb/musb_gadget.c
@@ -785,6 +785,9 @@ static void rxstate(struct musb *musb, struct musb_request *req)
musb_writew(epio, MUSB_RXCSR, csr);
buffer_aint_mapped:
+ fifo_count = min_t(unsigned int,
+ request->length - request->actual,
+ (unsigned int)fifo_count);
musb_read_fifo(musb_ep->hw_ep, fifo_count, (u8 *)
(request->buf + request->actual));
request->actual += fifo_count;
