This is a note to let you know that I've just added the patch titled
Revert "net: mdiobus: Fix memory leak in __mdiobus_register"
to the 4.9-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:
revert-net-mdiobus-fix-memory-leak-in-__mdiobus_register.patch
and it can be found in the queue-4.9 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From 10eff1f5788b6ffac212c254e2f3666219576889 Mon Sep 17 00:00:00 2001
From: Pavel Skripkin <paskripkin@xxxxxxxxx>
Date: Thu, 30 Sep 2021 20:49:42 +0300
Subject: Revert "net: mdiobus: Fix memory leak in __mdiobus_register"
From: Pavel Skripkin <paskripkin@xxxxxxxxx>
commit 10eff1f5788b6ffac212c254e2f3666219576889 upstream.
This reverts commit ab609f25d19858513919369ff3d9a63c02cd9e2e.
This patch is correct in the sense that we _should_ call device_put() in
case of device_register() failure, but the problem in this code is more
vast.
We need to set bus->state to UNMDIOBUS_REGISTERED before calling
device_register() to correctly release the device in mdiobus_free().
This patch prevents us from doing it, since in case of device_register()
failure put_device() will be called 2 times and it will cause UAF or
something else.
Also, Reported-by: tag in revered commit was wrong, since syzbot
reported different leak in same function.
Link: https://lore.kernel.org/netdev/20210928092657.GI2048@kadam/
Acked-by: Yanfei Xu <yanfei.xu@xxxxxxxxxxxxx>
Signed-off-by: Pavel Skripkin <paskripkin@xxxxxxxxx>
Link: https://lore.kernel.org/r/f12fb1faa4eccf0f355788225335eb4309ff2599.1633024062.git.paskripkin@xxxxxxxxx
Signed-off-by: Jakub Kicinski <kuba@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/net/phy/mdio_bus.c | 1 -
1 file changed, 1 deletion(-)
--- a/drivers/net/phy/mdio_bus.c
+++ b/drivers/net/phy/mdio_bus.c
@@ -326,7 +326,6 @@ int __mdiobus_register(struct mii_bus *b
err = device_register(&bus->dev);
if (err) {
pr_err("mii_bus %s failed to register\n", bus->id);
- put_device(&bus->dev);
return -EINVAL;
}
Patches currently in stable-queue which might be from paskripkin@xxxxxxxxx are
queue-4.9/revert-net-mdiobus-fix-memory-leak-in-__mdiobus_register.patch
