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 6.1-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-6.1 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit 149c2c8fcabda66d18e805fc1dd08408148d6d26 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 c672f92d65e97..9319a2675e7b6 100644 --- a/drivers/net/ethernet/seeq/ether3.c +++ b/drivers/net/ethernet/seeq/ether3.c @@ -847,9 +847,11 @@ 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); }