Merge tag 'linux-can-fixes-for-6.14-20250314' of git://git.kernel.org/pub/scm/linux/kernel/git/mkl/linux-can

Marc Kleine-Budde says:

====================
pull-request: can 2025-03-14

this is a pull request of 6 patches for net/main.

The first patch is by Vincent Mailhol and fixes an out of bound read
in strscpy() in the ucan driver.

Oliver Hartkopp contributes a patch for the af_can statistics to use
atomic access in the hot path.

The next 2 patches are by Biju Das, target the rcar_canfd driver and
fix the page entries in the AFL list.

The 2 patches by Haibo Chen for the flexcan driver fix the suspend and
resume functions.

linux-can-fixes-for-6.14-20250314

* tag 'linux-can-fixes-for-6.14-20250314' of git://git.kernel.org/pub/scm/linux/kernel/git/mkl/linux-can:
  can: flexcan: disable transceiver during system PM
  can: flexcan: only change CAN state when link up in system PM
  can: rcar_canfd: Fix page entries in the AFL list
  dt-bindings: can: renesas,rcar-canfd: Fix typo in pattern properties for R-Car V4M
  can: statistics: use atomic access in hot path
  can: ucan: fix out of bound read in strscpy() source
====================

Link: https://patch.msgid.link/20250314130909.2890541-1-mkl@pengutronix.de
Signed-off-by: Paolo Abeni <pabeni@redhat.com>

3 files changed, 44 insertions, 45 deletions

diff --git a/drivers/net/can/flexcan/flexcan-core.c b/drivers/net/can/flexcan/flexcan-core.c
index ac1a860986df..b080740bcb10 100644
--- a/drivers/net/can/flexcan/flexcan-core.c
+++ b/drivers/net/can/flexcan/flexcan-core.c
@@ -2260,14 +2260,19 @@ static int __maybe_unused flexcan_suspend(struct device *device)
 
 			flexcan_chip_interrupts_disable(dev);
 
+			err = flexcan_transceiver_disable(priv);
+			if (err)
+				return err;
+
 			err = pinctrl_pm_select_sleep_state(device);
 			if (err)
 				return err;
 		}
 		netif_stop_queue(dev);
 		netif_device_detach(dev);
+
+		priv->can.state = CAN_STATE_SLEEPING;
 	}
-	priv->can.state = CAN_STATE_SLEEPING;
 
 	return 0;
 }
@@ -2278,7 +2283,6 @@ static int __maybe_unused flexcan_resume(struct device *device)
 	struct flexcan_priv *priv = netdev_priv(dev);
 	int err;
 
-	priv->can.state = CAN_STATE_ERROR_ACTIVE;
 	if (netif_running(dev)) {
 		netif_device_attach(dev);
 		netif_start_queue(dev);
@@ -2292,12 +2296,20 @@ static int __maybe_unused flexcan_resume(struct device *device)
 			if (err)
 				return err;
 
-			err = flexcan_chip_start(dev);
+			err = flexcan_transceiver_enable(priv);
 			if (err)
 				return err;
 
+			err = flexcan_chip_start(dev);
+			if (err) {
+				flexcan_transceiver_disable(priv);
+				return err;
+			}
+
 			flexcan_chip_interrupts_enable(dev);
 		}
+
+		priv->can.state = CAN_STATE_ERROR_ACTIVE;
 	}
 
 	return 0;
diff --git a/drivers/net/can/rcar/rcar_canfd.c b/drivers/net/can/rcar/rcar_canfd.c
index df1a5d0b37b2..aa3df0d05b85 100644
--- a/drivers/net/can/rcar/rcar_canfd.c
+++ b/drivers/net/can/rcar/rcar_canfd.c
@@ -787,22 +787,14 @@ static void rcar_canfd_configure_controller(struct rcar_canfd_global *gpriv)
 }
 
 static void rcar_canfd_configure_afl_rules(struct rcar_canfd_global *gpriv,
-					   u32 ch)
+					   u32 ch, u32 rule_entry)
 {
-	u32 cfg;
-	int offset, start, page, num_rules = RCANFD_CHANNEL_NUMRULES;
+	int offset, page, num_rules = RCANFD_CHANNEL_NUMRULES;
+	u32 rule_entry_index = rule_entry % 16;
 	u32 ridx = ch + RCANFD_RFFIFO_IDX;
 
-	if (ch == 0) {
-		start = 0; /* Channel 0 always starts from 0th rule */
-	} else {
-		/* Get number of Channel 0 rules and adjust */
-		cfg = rcar_canfd_read(gpriv->base, RCANFD_GAFLCFG(ch));
-		start = RCANFD_GAFLCFG_GETRNC(gpriv, 0, cfg);
-	}
-
 	/* Enable write access to entry */
-	page = RCANFD_GAFL_PAGENUM(start);
+	page = RCANFD_GAFL_PAGENUM(rule_entry);
 	rcar_canfd_set_bit(gpriv->base, RCANFD_GAFLECTR,
 			   (RCANFD_GAFLECTR_AFLPN(gpriv, page) |
 			    RCANFD_GAFLECTR_AFLDAE));
@@ -818,13 +810,13 @@ static void rcar_canfd_configure_afl_rules(struct rcar_canfd_global *gpriv,
 		offset = RCANFD_C_GAFL_OFFSET;
 
 	/* Accept all IDs */
-	rcar_canfd_write(gpriv->base, RCANFD_GAFLID(offset, start), 0);
+	rcar_canfd_write(gpriv->base, RCANFD_GAFLID(offset, rule_entry_index), 0);
 	/* IDE or RTR is not considered for matching */
-	rcar_canfd_write(gpriv->base, RCANFD_GAFLM(offset, start), 0);
+	rcar_canfd_write(gpriv->base, RCANFD_GAFLM(offset, rule_entry_index), 0);
 	/* Any data length accepted */
-	rcar_canfd_write(gpriv->base, RCANFD_GAFLP0(offset, start), 0);
+	rcar_canfd_write(gpriv->base, RCANFD_GAFLP0(offset, rule_entry_index), 0);
 	/* Place the msg in corresponding Rx FIFO entry */
-	rcar_canfd_set_bit(gpriv->base, RCANFD_GAFLP1(offset, start),
+	rcar_canfd_set_bit(gpriv->base, RCANFD_GAFLP1(offset, rule_entry_index),
 			   RCANFD_GAFLP1_GAFLFDP(ridx));
 
 	/* Disable write access to page */
@@ -1851,6 +1843,7 @@ static int rcar_canfd_probe(struct platform_device *pdev)
 	unsigned long channels_mask = 0;
 	int err, ch_irq, g_irq;
 	int g_err_irq, g_recc_irq;
+	u32 rule_entry = 0;
 	bool fdmode = true;			/* CAN FD only mode - default */
 	char name[9] = "channelX";
 	int i;
@@ -2023,7 +2016,8 @@ static int rcar_canfd_probe(struct platform_device *pdev)
 		rcar_canfd_configure_tx(gpriv, ch);
 
 		/* Configure receive rules */
-		rcar_canfd_configure_afl_rules(gpriv, ch);
+		rcar_canfd_configure_afl_rules(gpriv, ch, rule_entry);
+		rule_entry += RCANFD_CHANNEL_NUMRULES;
 	}
 
 	/* Configure common interrupts */
diff --git a/drivers/net/can/usb/ucan.c b/drivers/net/can/usb/ucan.c
index 39a63b7313a4..07406daf7c88 100644
--- a/drivers/net/can/usb/ucan.c
+++ b/drivers/net/can/usb/ucan.c
@@ -186,7 +186,7 @@ union ucan_ctl_payload {
 	 */
 	struct ucan_ctl_cmd_get_protocol_version cmd_get_protocol_version;
 
-	u8 raw[128];
+	u8 fw_str[128];
 } __packed;
 
 enum {
@@ -424,18 +424,20 @@ static int ucan_ctrl_command_out(struct ucan_priv *up,
 			       UCAN_USB_CTL_PIPE_TIMEOUT);
 }
 
-static int ucan_device_request_in(struct ucan_priv *up,
-				  u8 cmd, u16 subcmd, u16 datalen)
+static void ucan_get_fw_str(struct ucan_priv *up, char *fw_str, size_t size)
 {
-	return usb_control_msg(up->udev,
-			       usb_rcvctrlpipe(up->udev, 0),
-			       cmd,
-			       USB_DIR_IN | USB_TYPE_VENDOR | USB_RECIP_DEVICE,
-			       subcmd,
-			       0,
-			       up->ctl_msg_buffer,
-			       datalen,
-			       UCAN_USB_CTL_PIPE_TIMEOUT);
+	int ret;
+
+	ret = usb_control_msg(up->udev, usb_rcvctrlpipe(up->udev, 0),
+			      UCAN_DEVICE_GET_FW_STRING,
+			      USB_DIR_IN | USB_TYPE_VENDOR |
+			      USB_RECIP_DEVICE,
+			      0, 0, fw_str, size - 1,
+			      UCAN_USB_CTL_PIPE_TIMEOUT);
+	if (ret > 0)
+		fw_str[ret] = '\0';
+	else
+		strscpy(fw_str, "unknown", size);
 }
 
 /* Parse the device information structure reported by the device and
@@ -1314,7 +1316,6 @@ static int ucan_probe(struct usb_interface *intf,
 	u8 in_ep_addr;
 	u8 out_ep_addr;
 	union ucan_ctl_payload *ctl_msg_buffer;
-	char firmware_str[sizeof(union ucan_ctl_payload) + 1];
 
 	udev = interface_to_usbdev(intf);
 
@@ -1527,17 +1528,6 @@ static int ucan_probe(struct usb_interface *intf,
 	 */
 	ucan_parse_device_info(up, &ctl_msg_buffer->cmd_get_device_info);
 
-	/* just print some device information - if available */
-	ret = ucan_device_request_in(up, UCAN_DEVICE_GET_FW_STRING, 0,
-				     sizeof(union ucan_ctl_payload));
-	if (ret > 0) {
-		/* copy string while ensuring zero termination */
-		strscpy(firmware_str, up->ctl_msg_buffer->raw,
-			sizeof(union ucan_ctl_payload) + 1);
-	} else {
-		strcpy(firmware_str, "unknown");
-	}
-
 	/* device is compatible, reset it */
 	ret = ucan_ctrl_command_out(up, UCAN_COMMAND_RESET, 0, 0);
 	if (ret < 0)
@@ -1555,7 +1545,10 @@ static int ucan_probe(struct usb_interface *intf,
 
 	/* initialisation complete, log device info */
 	netdev_info(up->netdev, "registered device\n");
-	netdev_info(up->netdev, "firmware string: %s\n", firmware_str);
+	ucan_get_fw_str(up, up->ctl_msg_buffer->fw_str,
+			sizeof(up->ctl_msg_buffer->fw_str));
+	netdev_info(up->netdev, "firmware string: %s\n",
+		    up->ctl_msg_buffer->fw_str);
 
 	/* success */
 	return 0;