xhci features for usb-next

PATCH New Mathias Nyman 1 participant 5 messages Apr 6, 2021

Subsystems (2)

USB USB xHCI driver

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Mathias Nyman

author

2021-04-06 07:00 UTC #0 lore raw

cover xhci features for usb-next

Hi Greg

I saw you already picked the Mediatek xhci patches.

Here are a few additional patches I had pending for usb-next but didn't get around to submit before easter.

Mostly fixing potential issues found by fuzzer and other tools.

Thanks
-Mathias

Mathias Nyman (4):
xhci: check port array allocation was successful before dereferencing
it
xhci: check control context is valid before dereferencing it.
xhci: fix potential array out of bounds with several interrupters
xhci: prevent double-fetch of transfer and transfer event TRBs

 drivers/usb/host/xhci-mem.c  |  3 +++
 drivers/usb/host/xhci-ring.c | 42 ++++++++++++++++--------------------
 drivers/usb/host/xhci.c      | 14 +++++++++++-
 3 files changed, 35 insertions(+), 24 deletions(-)

Signature · 1 line

2.25.1

Mathias Nyman

author

2021-04-06 07:00 UTC #1 lore raw

PATCH 1/4 xhci: check port array allocation was successful before dereferencing it

return if rhub->ports is null after rhub->ports = kcalloc_node() Klockwork reported issue

Signed-off-by Mathias Nyman <[email protected]>

---
 drivers/usb/host/xhci-mem.c | 3 +++
 1 file changed, 3 insertions(+)

drivers/usb/host/xhci-mem.c +3 -0

index 34d95c006751..f66815fe8482 100644
@@ -2249,6 +2249,9 @@ static void xhci_create_rhub_port_array(struct xhci_hcd *xhci,
 		return;
 	rhub->ports = kcalloc_node(rhub->num_ports, sizeof(*rhub->ports),
 			flags, dev_to_node(dev));
+	if (!rhub->ports)
+		return;
+
 	for (i = 0; i < HCS_MAX_PORTS(xhci->hcs_params1); i++) {
 		if (xhci->hw_ports[i].rhub != rhub ||
 		    xhci->hw_ports[i].hcd_portnum == DUPLICATE_ENTRY)

Signature · 1 line

2.25.1

Mathias Nyman

author

2021-04-06 07:00 UTC #2 lore raw

PATCH 2/4 xhci: check control context is valid before dereferencing it.

In reply to Mathias Nyman

Don't dereference ctrl_ctx before checking it's valid. Issue reported by Klockwork

Signed-off-by Mathias Nyman <[email protected]>

---
 drivers/usb/host/xhci.c | 8 ++++++++
 1 file changed, 8 insertions(+)

drivers/usb/host/xhci.c +8 -0

index 5d9fc3cd07a5..f9614716ecd7 100644
@@ -3261,6 +3261,14 @@ static void xhci_endpoint_reset(struct usb_hcd *hcd,
 
 	/* config ep command clears toggle if add and drop ep flags are set */
 	ctrl_ctx = xhci_get_input_control_ctx(cfg_cmd->in_ctx);
+	if (!ctrl_ctx) {
+		spin_unlock_irqrestore(&xhci->lock, flags);
+		xhci_free_command(xhci, cfg_cmd);
+		xhci_warn(xhci, "%s: Could not get input context, bad type.\n",
+				__func__);
+		goto cleanup;
+	}
+
 	xhci_setup_input_ctx_for_config_ep(xhci, cfg_cmd->in_ctx, vdev->out_ctx,
 					   ctrl_ctx, ep_flag, ep_flag);
 	xhci_endpoint_copy(xhci, cfg_cmd->in_ctx, vdev->out_ctx, ep_index);

Signature · 1 line

2.25.1

Mathias Nyman

author

2021-04-06 07:00 UTC #3 lore raw

PATCH 3/4 xhci: fix potential array out of bounds with several interrupters

In reply to Mathias Nyman

The Max Interrupters supported by the controller is given in a 10bit wide bitfield, but the driver uses a fixed 128 size array to index these interrupters.

Klockwork reports a possible array out of bounds case which in theory is possible. In practice this hasn't been hit as a common number of Max Interrupters for new controllers is 8, not even close to 128.

This needs to be fixed anyway

Signed-off-by Mathias Nyman <[email protected]>

---
 drivers/usb/host/xhci.c | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

drivers/usb/host/xhci.c +5 -1

index f9614716ecd7..ca9385d22f68 100644
@@ -227,6 +227,7 @@ static void xhci_zero_64b_regs(struct xhci_hcd *xhci)
 	struct device *dev = xhci_to_hcd(xhci)->self.sysdev;
 	int err, i;
 	u64 val;
+	u32 intrs;
 
 	/*
 	 * Some Renesas controllers get into a weird state if they are

@@ -265,7 +266,10 @@ static void xhci_zero_64b_regs(struct xhci_hcd *xhci)
 	if (upper_32_bits(val))
 		xhci_write_64(xhci, 0, &xhci->op_regs->cmd_ring);
 
-	for (i = 0; i < HCS_MAX_INTRS(xhci->hcs_params1); i++) {
+	intrs = min_t(u32, HCS_MAX_INTRS(xhci->hcs_params1),
+		      ARRAY_SIZE(xhci->run_regs->ir_set));
+
+	for (i = 0; i < intrs; i++) {
 		struct xhci_intr_reg __iomem *ir;
 
 		ir = &xhci->run_regs->ir_set[i];

Signature · 1 line

2.25.1

Mathias Nyman

author

2021-04-06 07:00 UTC #4 lore raw

PATCH 4/4 xhci: prevent double-fetch of transfer and transfer event TRBs

In reply to Mathias Nyman

The same values are parsed several times from transfer and event TRBs by different functions in the same call path, all while processing one transfer event.

As the TRBs are in DMA memory and can be accessed by the xHC host we want to avoid this to prevent double-fetch issues.

To resolve this pass the already parsed values to the different functions in the path of parsing a transfer event

Signed-off-by Mathias Nyman <[email protected]>

---
 drivers/usb/host/xhci-ring.c | 42 ++++++++++++++++--------------------
 1 file changed, 19 insertions(+), 23 deletions(-)

drivers/usb/host/xhci-ring.c +19 ~~-23~~

index 1eee60ac518f..05c38dd3ee36 100644
@@ -2128,16 +2128,13 @@ int xhci_is_vendor_info_code(struct xhci_hcd *xhci, unsigned int trb_comp_code)
 	return 0;
 }
 
-static int finish_td(struct xhci_hcd *xhci, struct xhci_td *td,
-	struct xhci_transfer_event *event, struct xhci_virt_ep *ep)
+static int finish_td(struct xhci_hcd *xhci, struct xhci_virt_ep *ep,
+		     struct xhci_ring *ep_ring, struct xhci_td *td,
+		     u32 trb_comp_code)
 {
 	struct xhci_ep_ctx *ep_ctx;
-	struct xhci_ring *ep_ring;
-	u32 trb_comp_code;
 
-	ep_ring = xhci_dma_to_transfer_ring(ep, le64_to_cpu(event->buffer));
 	ep_ctx = xhci_get_ep_ctx(xhci, ep->vdev->out_ctx, ep->ep_index);
-	trb_comp_code = GET_COMP_CODE(le32_to_cpu(event->transfer_len));
 
 	switch (trb_comp_code) {
 	case COMP_STOPPED_LENGTH_INVALID:

@@ -2233,9 +2230,9 @@ static int sum_trb_lengths(struct xhci_hcd *xhci, struct xhci_ring *ring,
 /*
  * Process control tds, update urb status and actual_length.
  */
-static int process_ctrl_td(struct xhci_hcd *xhci, struct xhci_td *td,
-	union xhci_trb *ep_trb, struct xhci_transfer_event *event,
-	struct xhci_virt_ep *ep)
+static int process_ctrl_td(struct xhci_hcd *xhci, struct xhci_virt_ep *ep,
+		struct xhci_ring *ep_ring,  struct xhci_td *td,
+			   union xhci_trb *ep_trb, struct xhci_transfer_event *event)
 {
 	struct xhci_ep_ctx *ep_ctx;
 	u32 trb_comp_code;

@@ -2323,15 +2320,15 @@ static int process_ctrl_td(struct xhci_hcd *xhci, struct xhci_td *td,
 		td->urb->actual_length = requested;
 
 finish_td:
-	return finish_td(xhci, td, event, ep);
+	return finish_td(xhci, ep, ep_ring, td, trb_comp_code);
 }
 
 /*
  * Process isochronous tds, update urb packet status and actual_length.
  */
-static int process_isoc_td(struct xhci_hcd *xhci, struct xhci_td *td,
-	union xhci_trb *ep_trb, struct xhci_transfer_event *event,
-	struct xhci_virt_ep *ep)
+static int process_isoc_td(struct xhci_hcd *xhci, struct xhci_virt_ep *ep,
+		struct xhci_ring *ep_ring, struct xhci_td *td,
+		union xhci_trb *ep_trb, struct xhci_transfer_event *event)
 {
 	struct urb_priv *urb_priv;
 	int idx;

@@ -2408,7 +2405,7 @@ static int process_isoc_td(struct xhci_hcd *xhci, struct xhci_td *td,
 
 	td->urb->actual_length += frame->actual_length;
 
-	return finish_td(xhci, td, event, ep);
+	return finish_td(xhci, ep, ep_ring, td, trb_comp_code);
 }
 
 static int skip_isoc_td(struct xhci_hcd *xhci, struct xhci_td *td,

@@ -2440,17 +2437,15 @@ static int skip_isoc_td(struct xhci_hcd *xhci, struct xhci_td *td,
 /*
  * Process bulk and interrupt tds, update urb status and actual_length.
  */
-static int process_bulk_intr_td(struct xhci_hcd *xhci, struct xhci_td *td,
-	union xhci_trb *ep_trb, struct xhci_transfer_event *event,
-	struct xhci_virt_ep *ep)
+static int process_bulk_intr_td(struct xhci_hcd *xhci, struct xhci_virt_ep *ep,
+		struct xhci_ring *ep_ring, struct xhci_td *td,
+		union xhci_trb *ep_trb, struct xhci_transfer_event *event)
 {
 	struct xhci_slot_ctx *slot_ctx;
-	struct xhci_ring *ep_ring;
 	u32 trb_comp_code;
 	u32 remaining, requested, ep_trb_len;
 
 	slot_ctx = xhci_get_slot_ctx(xhci, ep->vdev->out_ctx);
-	ep_ring = xhci_dma_to_transfer_ring(ep, le64_to_cpu(event->buffer));
 	trb_comp_code = GET_COMP_CODE(le32_to_cpu(event->transfer_len));
 	remaining = EVENT_TRB_LEN(le32_to_cpu(event->transfer_len));
 	ep_trb_len = TRB_LEN(le32_to_cpu(ep_trb->generic.field[2]));

@@ -2510,7 +2505,8 @@ static int process_bulk_intr_td(struct xhci_hcd *xhci, struct xhci_td *td,
 			  remaining);
 		td->urb->actual_length = 0;
 	}
-	return finish_td(xhci, td, event, ep);
+
+	return finish_td(xhci, ep, ep_ring, td, trb_comp_code);
 }
 
 /*

@@ -2853,11 +2849,11 @@ static int handle_tx_event(struct xhci_hcd *xhci,
 
 		/* update the urb's actual_length and give back to the core */
 		if (usb_endpoint_xfer_control(&td->urb->ep->desc))
-			process_ctrl_td(xhci, td, ep_trb, event, ep);
+			process_ctrl_td(xhci, ep, ep_ring, td, ep_trb, event);
 		else if (usb_endpoint_xfer_isoc(&td->urb->ep->desc))
-			process_isoc_td(xhci, td, ep_trb, event, ep);
+			process_isoc_td(xhci, ep, ep_ring, td, ep_trb, event);
 		else
-			process_bulk_intr_td(xhci, td, ep_trb, event, ep);
+			process_bulk_intr_td(xhci, ep, ep_ring, td, ep_trb, event);
 cleanup:
 		handling_skipped_tds = ep->skip &&
 			trb_comp_code != COMP_MISSED_SERVICE_ERROR &&

Signature · 1 line

2.25.1