Re: [PATCH] CAN: Use inode instead of kernel address for /proc file

[Oliver Hartkopp <socketcan@hartkopp.net>]

On 25.12.2010 23:22, Oliver Hartkopp wrote:
> On 25.12.2010 23:16, Dan Rosenberg wrote:
>> Since the socket address is just being used as a unique identifier, its
>> inode number is an alternative that does not leak potentially sensitive
>> information.
>>
>> CC-ing stable because MITRE has assigned CVE-2010-4565 to the issue.
>>
>> Signed-off-by: Dan Rosenberg <drosenberg@vsecurity.com>
>> Cc: stable <stable@kernel.org>
> 
> Acked-by: Oliver Hartkopp <socketcan@hartkopp.net>
> 
> Thanks Dan.
> 
>> ---
>>  net/can/bcm.c |    4 ++--
>>  1 files changed, 2 insertions(+), 2 deletions(-)
>>
>> diff --git a/net/can/bcm.c b/net/can/bcm.c
>> index 6faa825..5748901 100644
>> --- a/net/can/bcm.c
>> +++ b/net/can/bcm.c
>> @@ -1520,8 +1520,8 @@ static int bcm_connect(struct socket *sock, struct sockaddr *uaddr, int len,
>>  	bo->bound = 1;
>>  
>>  	if (proc_dir) {
>> -		/* unique socket address as filename */
>> -		sprintf(bo->procname, "%p", sock);
>> +		/* socket inode as filename */
>> +		sprintf(bo->procname, "%lx", sock_i_ino(sk));

One minor question:

AFAIK the inode numbers that can be found in /proc/<pid>/fd/* are in decimal
and not in hex, right?

If so, you should use '%lu' instead of '%lx' in the patch.

Regards,
Oliver