Thread (23 messages) 23 messages, 8 authors, 2021-09-29

Re: [PATCH] net: mdiobus: Fix memory leak in __mdiobus_register

From: Pavel Skripkin <hidden>
Date: 2021-09-28 10:47:03
Also in: lkml

On 9/28/21 13:39, Dan Carpenter wrote:
No, the syzbot link was correct.
Link is correct, but Yanfei's patch does not fix this bug. Syzbot 
reported leak, that you described below, not the Yanfei one.
quoted hunk ↗ jump to hunk
You gave me that link again but I think you must be complaining about
a different bug which involves mdiobus_free().  Your bug is something
like this:

drivers/staging/netlogic/xlr_net.c
    838          err = mdiobus_register(priv->mii_bus);
    839          if (err) {
    840                  mdiobus_free(priv->mii_bus);

This error path will leak.

    841                  pr_err("mdio bus registration failed\n");
    842                  return err;
    843          }

Your patch is more complicated than necessary...  Just do:
diff --git a/drivers/net/phy/mdio_bus.c b/drivers/net/phy/mdio_bus.c
index ee8313a4ac71..c380a30a77bc 100644
--- a/drivers/net/phy/mdio_bus.c
+++ b/drivers/net/phy/mdio_bus.c
@@ -538,6 +538,7 @@ int __mdiobus_register(struct mii_bus *bus, struct module *owner)
  	bus->dev.groups = NULL;
  	dev_set_name(&bus->dev, "%s", bus->id);
  
+	bus->state = MDIOBUS_UNREGISTERED;
  	err = device_register(&bus->dev);
  	if (err) {
  		pr_err("mii_bus %s failed to register\n", bus->id);
yep, it's the same as mine, but I thought, that MDIOBUS_UNREGISTERED is 
not correct name for this state :) Anyway, thank you for suggestion



With regards,
Pavel Skripkin
Keyboard shortcuts
hback out one level
jnext message in thread
kprevious message in thread
ldrill in
Escclose help / fold thread tree
?toggle this help