Re: [PATCH 00/10] Kernel memory leak detector 0.8

["Michal Piotrowski" <michal.k.k.piotrowski@gmail.com>]

On 11/07/06, Catalin Marinas <catalin.marinas@gmail.com> wrote:
> > orphan pointer 0xc6113bec (size 28):
> >   c017392a: <__kmalloc_track_caller>
> >   c01631b1: <__kzalloc>
> >   c010b7d7: <legacy_init_iomem_resources>
> >   c010b89c: <request_standard_resources>
> >   c0100b8b: <do_initcalls>
> >   c0100c3d: <do_basic_setup>
> >   c0100cdb: <init>
>
> That's a real leak. I posted a patch last night that solves this issue
> - http://lkml.org/lkml/2006/7/10/370

Thanks.

>
> > This is most common
> > orphan pointer 0xf5a6fd60 (size 39):
> >   c0173822: <__kmalloc>
> >   c01df500: <context_struct_to_string>
> >   c01df679: <security_sid_to_context>
> >   c01d7eee: <selinux_socket_getpeersec_dgram>
> >   f884f019: <unix_get_peersec_dgram>
> >   f8850698: <unix_dgram_sendmsg>
> >   c02a88c2: <sock_sendmsg>
> >   c02a9c7a: <sys_sendto>
>
> Looking at the call trace, the pointer to the memory allocated in
> context_struct_to_string() is stored in the "cb" variable in struct
> sk_buff (argument passed to selinux_socket_getpeersec_dgram from
> unix_get_peersec_dgram).
>
> This pointer should be found when scanning the "struct sk_buff"
> blocks, unless you also get a comparable number of "struct sk_buff"
> reports (from __alloc_skb). If not, it might be a real leak.

So if we got 3970
orphan pointer 0xf5a6fd60 (size 39):
  c0173822: <__kmalloc>
  c01df500: <context_struct_to_string>
  c01df679: <security_sid_to_context>
  c01d7eee: <selinux_socket_getpeersec_dgram>
  f884f019: <unix_get_peersec_dgram>
  f8850698: <unix_dgram_sendmsg>
  c02a88c2: <sock_sendmsg>
  c02a9c7a: <sys_sendto>

and 4673
orphan pointer 0xf4249488 (size 29):
  c0173822: <__kmalloc>
  c01df500: <context_struct_to_string>
  c01df679: <security_sid_to_context>
  c01d7eee: <selinux_socket_getpeersec_dgram>
  f884f019: <unix_get_peersec_dgram>
  f8850698: <unix_dgram_sendmsg>
  c02a8d68: <do_sock_write>
  c02a8e85: <sock_aio_write>

It's not a memleak?

http://www.stardust.webpages.pl/files/o_bugs/kml/ml3.txt

>
> --
> Catalin
>

Regards,
Michal

-- 
Michal K. K. Piotrowski
LTG - Linux Testers Group
(http://www.stardust.webpages.pl/ltg/wiki/)