| From | Greg Kroah-Hartman <> | Subject | [PATCH 5.15 025/171] can: m_can: m_can_read_fifo: fix memory leak in error branch | Date | Mon, 13 Dec 2021 10:29:00 +0100 |
| |
From: Vincent Mailhol <mailhol.vincent@wanadoo.fr>
commit 31cb32a590d62b18f69a9a6d433f4e69c74fdd56 upstream.
In m_can_read_fifo(), if the second call to m_can_fifo_read() fails, the function jump to the out_fail label and returns without calling m_can_receive_skb(). This means that the skb previously allocated by alloc_can_skb() is not freed. In other terms, this is a memory leak.
This patch adds a goto label to destroy the skb if an error occurs.
Issue was found with GCC -fanalyzer, please follow the link below for details.
Fixes: e39381770ec9 ("can: m_can: Disable IRQs on FIFO bus errors") Link: https://lore.kernel.org/all/20211107050755.70655-1-mailhol.vincent@wanadoo.fr Cc: stable@vger.kernel.org Cc: Matt Kline <matt@bitbashing.io> Signed-off-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr> Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> --- drivers/net/can/m_can/m_can.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-)
--- a/drivers/net/can/m_can/m_can.c +++ b/drivers/net/can/m_can/m_can.c @@ -517,7 +517,7 @@ static int m_can_read_fifo(struct net_de err = m_can_fifo_read(cdev, fgi, M_CAN_FIFO_DATA, cf->data, DIV_ROUND_UP(cf->len, 4)); if (err) - goto out_fail; + goto out_free_skb; } /* acknowledge rx fifo 0 */ @@ -532,6 +532,8 @@ static int m_can_read_fifo(struct net_de return 0; +out_free_skb: + kfree_skb(skb); out_fail: netdev_err(dev, "FIFO read returned %d\n", err); return err;
|