[PATCH 5.10 36/43] can: mcp251xfd: mcp251xfd_handle_rxif_one(): fix wrong NULL pointer check

From: Greg Kroah-Hartman
Date: Fri Jan 22 2021 - 09:48:26 EST


From: Qinglang Miao <miaoqinglang@xxxxxxxxxx>

[ Upstream commit ca4c6ebeeb50112f5178f14bfb6d9e8ddf148545 ]

If alloc_canfd_skb() returns NULL, 'cfg' is an uninitialized variable, so we
should check 'skb' rather than 'cfd' after calling alloc_canfd_skb(priv->ndev,
&cfd).

Fixes: 55e5b97f003e ("can: mcp25xxfd: add driver for Microchip MCP25xxFD SPI CAN")
Signed-off-by: Qinglang Miao <miaoqinglang@xxxxxxxxxx>
Reviewed-by: Manivannan Sadhasivam <manivannan.sadhasivam@xxxxxxxxxx>
Link: https://lore.kernel.org/r/20210113073100.79552-1-miaoqinglang@xxxxxxxxxx
Signed-off-by: Marc Kleine-Budde <mkl@xxxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/net/can/spi/mcp251xfd/mcp251xfd-core.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

--- a/drivers/net/can/spi/mcp251xfd/mcp251xfd-core.c
+++ b/drivers/net/can/spi/mcp251xfd/mcp251xfd-core.c
@@ -1432,7 +1432,7 @@ mcp251xfd_handle_rxif_one(struct mcp251x
else
skb = alloc_can_skb(priv->ndev, (struct can_frame **)&cfd);

- if (!cfd) {
+ if (!skb) {
stats->rx_dropped++;
return 0;
}