From: Henry Tian tianxiaofeng@bytedance.com
[ Upstream commit 83045e19feae937c425248824d1dc0fc95583842 ]
In ast_vhub_epn_handle_ack() when the received data length exceeds the buffer, it does not check the case and just copies to req.buf and cause a buffer overflow, kernel oops on this case.
This issue could be reproduced on a BMC with an OS that enables the lan over USB: 1. In OS, enable the usb eth dev, verify it pings the BMC OK; 2. In OS, set the usb dev mtu to 2000. (Default is 1500); 3. In OS, ping the BMC with `-s 2000` argument.
The BMC kernel will get oops with below logs:
skbuff: skb_over_panic: text:8058e098 len:2048 put:2048 head:84c678a0 data:84c678c2 tail:0x84c680c2 end:0x84c67f00 dev:usb0 ------------[ cut here ]------------ kernel BUG at net/core/skbuff.c:113! Internal error: Oops - BUG: 0 [#1] ARM CPU: 0 PID: 0 Comm: swapper Not tainted 5.15.69-c9fb275-dirty-d1e579a #1 Hardware name: Generic DT based system PC is at skb_panic+0x60/0x6c LR is at irq_work_queue+0x6c/0x94
Fix the issue by checking the length and set `-EOVERFLOW`.
Tested: Verify the BMC kernel does not get oops in the above case, and the usb ethernet gets RX packets errors instead.
Signed-off-by: Lei YU yulei.sh@bytedance.com Signed-off-by: Henry Tian tianxiaofeng@bytedance.com Reviewed-by: Neal Liu neal_liu@aspeedtech.com Acked-by: Benjamin Herrenschmidt benh@kernel.crashing.org Link: https://lore.kernel.org/r/20221024094853.2877441-1-yulei.sh@bytedance.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/usb/gadget/udc/aspeed-vhub/core.c | 2 +- drivers/usb/gadget/udc/aspeed-vhub/epn.c | 16 ++++++++++++---- 2 files changed, 13 insertions(+), 5 deletions(-)
diff --git a/drivers/usb/gadget/udc/aspeed-vhub/core.c b/drivers/usb/gadget/udc/aspeed-vhub/core.c index 902e61be4d64..7ce4dc132da3 100644 --- a/drivers/usb/gadget/udc/aspeed-vhub/core.c +++ b/drivers/usb/gadget/udc/aspeed-vhub/core.c @@ -42,7 +42,7 @@ void ast_vhub_done(struct ast_vhub_ep *ep, struct ast_vhub_req *req,
list_del_init(&req->queue);
- if (req->req.status == -EINPROGRESS) + if ((req->req.status == -EINPROGRESS) || (status == -EOVERFLOW)) req->req.status = status;
if (req->req.dma) { diff --git a/drivers/usb/gadget/udc/aspeed-vhub/epn.c b/drivers/usb/gadget/udc/aspeed-vhub/epn.c index 931f540a747e..32c381b3ed40 100644 --- a/drivers/usb/gadget/udc/aspeed-vhub/epn.c +++ b/drivers/usb/gadget/udc/aspeed-vhub/epn.c @@ -89,6 +89,7 @@ static void ast_vhub_epn_handle_ack(struct ast_vhub_ep *ep) { struct ast_vhub_req *req; unsigned int len; + int status = 0; u32 stat;
/* Read EP status */ @@ -124,9 +125,15 @@ static void ast_vhub_epn_handle_ack(struct ast_vhub_ep *ep) len = VHUB_EP_DMA_TX_SIZE(stat);
/* If not using DMA, copy data out if needed */ - if (!req->req.dma && !ep->epn.is_in && len) - memcpy(req->req.buf + req->req.actual, ep->buf, len); - + if (!req->req.dma && !ep->epn.is_in && len) { + if (req->req.actual + len > req->req.length) { + req->last_desc = 1; + status = -EOVERFLOW; + goto done; + } else { + memcpy(req->req.buf + req->req.actual, ep->buf, len); + } + } /* Adjust size */ req->req.actual += len;
@@ -134,9 +141,10 @@ static void ast_vhub_epn_handle_ack(struct ast_vhub_ep *ep) if (len < ep->ep.maxpacket) req->last_desc = 1;
+done: /* That's it ? complete the request and pick a new one */ if (req->last_desc >= 0) { - ast_vhub_done(ep, req, 0); + ast_vhub_done(ep, req, status); req = list_first_entry_or_null(&ep->queue, struct ast_vhub_req, queue);