This is a note to let you know that I've just added the patch titled
net: seeq: Fix use after free vulnerability in ether3 Driver Due to Race Condition
to the 4.19-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:
net-seeq-fix-use-after-free-vulnerability-in-ether3-.patch
and it can be found in the queue-4.19 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit baa628a28327e0a8dbc4898cc2af0e60e5ebeef2
Author: Kaixin Wang <kxwang23@xxxxxxxxxxxxxx>
Date: Sun Sep 15 22:40:46 2024 +0800
net: seeq: Fix use after free vulnerability in ether3 Driver Due to Race Condition
[ Upstream commit b5109b60ee4fcb2f2bb24f589575e10cc5283ad4 ]
In the ether3_probe function, a timer is initialized with a callback
function ether3_ledoff, bound to &prev(dev)->timer. Once the timer is
started, there is a risk of a race condition if the module or device
is removed, triggering the ether3_remove function to perform cleanup.
The sequence of operations that may lead to a UAF bug is as follows:
CPU0 CPU1
| ether3_ledoff
ether3_remove |
free_netdev(dev); |
put_devic |
kfree(dev); |
| ether3_outw(priv(dev)->regs.config2 |= CFG2_CTRLO, REG_CONFIG2);
| // use dev
Fix it by ensuring that the timer is canceled before proceeding with
the cleanup in ether3_remove.
Fixes: 6fd9c53f7186 ("net: seeq: Convert timers to use timer_setup()")
Signed-off-by: Kaixin Wang <kxwang23@xxxxxxxxxxxxxx>
Link: https://patch.msgid.link/20240915144045.451-1-kxwang23@xxxxxxxxxxxxxx
Signed-off-by: Paolo Abeni <pabeni@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/drivers/net/ethernet/seeq/ether3.c b/drivers/net/ethernet/seeq/ether3.c
index d1bb73bf99148..a612ca6418883 100644
--- a/drivers/net/ethernet/seeq/ether3.c
+++ b/drivers/net/ethernet/seeq/ether3.c
@@ -851,9 +851,11 @@ static void ether3_remove(struct expansion_card *ec)
{
struct net_device *dev = ecard_get_drvdata(ec);
+ ether3_outw(priv(dev)->regs.config2 |= CFG2_CTRLO, REG_CONFIG2);
ecard_set_drvdata(ec, NULL);
unregister_netdev(dev);
+ del_timer_sync(&priv(dev)->timer);
free_netdev(dev);
ecard_release_resources(ec);
}
