netdev - Re: [PATCH v2] net: mdiobus: fix an OF node reference leak

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [day] [month] [year] [list]

Message-ID: <af6056e1-8cc8-4f2a-a94a-061cba63a2ef@pf.is.s.u-tokyo.ac.jp>
Date: Mon, 16 Dec 2024 10:41:52 +0900
From: Joe Hattori <joe@...is.s.u-tokyo.ac.jp>
To: Andrew Lunn <andrew@...n.ch>
Cc: hkallweit1@...il.com, linux@...linux.org.uk, davem@...emloft.net,
 edumazet@...gle.com, kuba@...nel.org, pabeni@...hat.com,
 netdev@...r.kernel.org
Subject: Re: [PATCH v2] net: mdiobus: fix an OF node reference leak



On 12/16/24 01:06, Andrew Lunn wrote:
> On Sun, Dec 15, 2024 at 08:24:17PM +0900, Joe Hattori wrote:
>> fwnode_find_mii_timestamper() calls of_parse_phandle_with_fixed_args()
>> but does not decrement the refcount of the obtained OF node. Add an
>> of_node_put() call before returning from the function.
>>
>> This bug was detected by an experimental static analysis tool that I am
>> developing.
>>
>> Fixes: bc1bee3b87ee ("net: mdiobus: Introduce fwnode_mdiobus_register_phy()")
>> Signed-off-by: Joe Hattori <joe@...is.s.u-tokyo.ac.jp>
>> ---
>> Changes in v2:
>> - Call of_node_put() after calling register_mii_timestamper() to avoid
>>    UAF.
>> ---
>>   drivers/net/mdio/fwnode_mdio.c | 5 ++++-
>>   1 file changed, 4 insertions(+), 1 deletion(-)
>>
>> diff --git a/drivers/net/mdio/fwnode_mdio.c b/drivers/net/mdio/fwnode_mdio.c
>> index b156493d7084..456f829e4d6d 100644
>> --- a/drivers/net/mdio/fwnode_mdio.c
>> +++ b/drivers/net/mdio/fwnode_mdio.c
>> @@ -41,6 +41,7 @@ static struct mii_timestamper *
>>   fwnode_find_mii_timestamper(struct fwnode_handle *fwnode)
>>   {
>>   	struct of_phandle_args arg;
>> +	struct mii_timestamper *mii_ts;
>>   	int err;
>>   
>>   	if (is_acpi_node(fwnode))
>> @@ -56,7 +57,9 @@ fwnode_find_mii_timestamper(struct fwnode_handle *fwnode)
>>   	if (arg.args_count != 1)
>>   		return ERR_PTR(-EINVAL);
> 
> Is there no need to put the node when arg.args_count != 1 ?

Yes, should have caught that. Fixed in the v3 patch.
> 
> 	Andrew

Best,
Joe