From: Dario Binacchi Date: Fri, 22 Nov 2024 22:15:45 +0000 (+0100) Subject: can: hi311x: hi3110_can_ist(): fix potential use-after-free X-Git-Url: https://www.infradead.org/git/?a=commitdiff_plain;h=9ad86d377ef4a19c75a9c639964879a5b25a433b;p=users%2Fjedix%2Flinux-maple.git can: hi311x: hi3110_can_ist(): fix potential use-after-free The commit a22bd630cfff ("can: hi311x: do not report txerr and rxerr during bus-off") removed the reporting of rxerr and txerr even in case of correct operation (i. e. not bus-off). The error count information added to the CAN frame after netif_rx() is a potential use after free, since there is no guarantee that the skb is in the same state. It might be freed or reused. Fix the issue by postponing the netif_rx() call in case of txerr and rxerr reporting. Fixes: a22bd630cfff ("can: hi311x: do not report txerr and rxerr during bus-off") Signed-off-by: Dario Binacchi Link: https://patch.msgid.link/20241122221650.633981-5-dario.binacchi@amarulasolutions.com Signed-off-by: Marc Kleine-Budde --- diff --git a/drivers/net/can/spi/hi311x.c b/drivers/net/can/spi/hi311x.c index 148d974ebb21..b67464df25ff 100644 --- a/drivers/net/can/spi/hi311x.c +++ b/drivers/net/can/spi/hi311x.c @@ -671,9 +671,9 @@ static irqreturn_t hi3110_can_ist(int irq, void *dev_id) tx_state = txerr >= rxerr ? new_state : 0; rx_state = txerr <= rxerr ? new_state : 0; can_change_state(net, cf, tx_state, rx_state); - netif_rx(skb); if (new_state == CAN_STATE_BUS_OFF) { + netif_rx(skb); can_bus_off(net); if (priv->can.restart_ms == 0) { priv->force_quit = 1; @@ -684,6 +684,7 @@ static irqreturn_t hi3110_can_ist(int irq, void *dev_id) cf->can_id |= CAN_ERR_CNT; cf->data[6] = txerr; cf->data[7] = rxerr; + netif_rx(skb); } }