6.12-stable review patch. If anyone has any objections, please let me know.
------------------
From: Dario Binacchi <dario.binacchi@xxxxxxxxxxxxxxxxxxxx>
[ Upstream commit 9ad86d377ef4a19c75a9c639964879a5b25a433b ]
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 <dario.binacchi@xxxxxxxxxxxxxxxxxxxx>
Link: https://patch.msgid.link/20241122221650.633981-5-dario.binacchi@xxxxxxxxxxxxxxxxxxxx
Signed-off-by: Marc Kleine-Budde <mkl@xxxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/net/can/spi/hi311x.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/drivers/net/can/spi/hi311x.c b/drivers/net/can/spi/hi311x.c
index 148d974ebb210..b67464df25ffe 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);
}
}
--
2.43.0
