--- /dev/null
+From foo@baz Tue Jul 19 01:38:52 PM CEST 2022
+From: Marc Kleine-Budde <mkl@pengutronix.de>
+Date: Thu, 17 Mar 2022 08:57:35 +0100
+Subject: can: m_can: m_can_tx_handler(): fix use after free of skb
+
+From: Marc Kleine-Budde <mkl@pengutronix.de>
+
+commit 2e8e79c416aae1de224c0f1860f2e3350fa171f8 upstream.
+
+can_put_echo_skb() will clone skb then free the skb. Move the
+can_put_echo_skb() for the m_can version 3.0.x directly before the
+start of the xmit in hardware, similar to the 3.1.x branch.
+
+Fixes: 80646733f11c ("can: m_can: update to support CAN FD features")
+Link: https://lore.kernel.org/all/20220317081305.739554-1-mkl@pengutronix.de
+Cc: stable@vger.kernel.org
+Reported-by: Hangyu Hua <hbh25y@gmail.com>
+Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
+[sudip: adjust context]
+Signed-off-by: Sudip Mukherjee <sudipm.mukherjee@gmail.com>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+---
+ drivers/net/can/m_can/m_can.c | 5 +++--
+ 1 file changed, 3 insertions(+), 2 deletions(-)
+
+--- a/drivers/net/can/m_can/m_can.c
++++ b/drivers/net/can/m_can/m_can.c
+@@ -1438,8 +1438,6 @@ static netdev_tx_t m_can_start_xmit(stru
+ M_CAN_FIFO_DATA(i / 4),
+ *(u32 *)(cf->data + i));
+
+- can_put_echo_skb(skb, dev, 0);
+-
+ if (priv->can.ctrlmode & CAN_CTRLMODE_FD) {
+ cccr = m_can_read(priv, M_CAN_CCCR);
+ cccr &= ~(CCCR_CMR_MASK << CCCR_CMR_SHIFT);
+@@ -1456,6 +1454,9 @@ static netdev_tx_t m_can_start_xmit(stru
+ m_can_write(priv, M_CAN_CCCR, cccr);
+ }
+ m_can_write(priv, M_CAN_TXBTIE, 0x1);
++
++ can_put_echo_skb(skb, dev, 0);
++
+ m_can_write(priv, M_CAN_TXBAR, 0x1);
+ /* End of xmit function for version 3.0.x */
+ } else {