This is a note to let you know that I've just added the patch titled
can: m_can: m_can_read_fifo: fix memory leak in error branch
to the 5.15-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
can-m_can-m_can_read_fifo-fix-memory-leak-in-error-branch.patch
and it can be found in the queue-5.15 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From 31cb32a590d62b18f69a9a6d433f4e69c74fdd56 Mon Sep 17 00:00:00 2001
From: Vincent Mailhol <mailhol.vincent@xxxxxxxxxx>
Date: Sun, 7 Nov 2021 14:07:55 +0900
Subject: can: m_can: m_can_read_fifo: fix memory leak in error branch
From: Vincent Mailhol <mailhol.vincent@xxxxxxxxxx>
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@xxxxxxxxxx
Cc: stable@xxxxxxxxxxxxxxx
Cc: Matt Kline <matt@xxxxxxxxxxxxx>
Signed-off-by: Vincent Mailhol <mailhol.vincent@xxxxxxxxxx>
Signed-off-by: Marc Kleine-Budde <mkl@xxxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
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;
Patches currently in stable-queue which might be from mailhol.vincent@xxxxxxxxxx are
queue-5.15/can-pch_can-pch_can_rx_normal-fix-use-after-free.patch
queue-5.15/can-m_can-m_can_read_fifo-fix-memory-leak-in-error-branch.patch
