[ovs-dev] [PATCH ovn] ovn-northd: Fix memory leak in case of distributed NAT.

[Ilya Maximets]

On 5/13/20 12:19 PM, Dumitru Ceara wrote:
> In function get_nat_addresses(), memory reserved for c_addresses is not
> freed in case of distributed NAT (i.e., central_ip_address == false):
> 
> ==22493== 36 bytes in 2 blocks are definitely lost in loss record 176
> of 444
> ==22493==    at 0x4C29DAD: malloc (vg_replace_malloc.c:308)
> ==22493==    by 0x4C2C100: realloc (vg_replace_malloc.c:836)
> ==22493==    by 0x4E3E9D: xrealloc (util.c:149)
> ==22493==    by 0x47EEBB: ds_reserve (dynamic-string.c:63)
> ==22493==    by 0x47F32E: ds_put_format_valist (dynamic-string.c:161)
> ==22493==    by 0x47F258: ds_put_format (dynamic-string.c:142)
> ==22493==    by 0x40D74E: get_nat_addresses (ovn-northd.c:2337)
> ==22493==    by 0x40F75B: ovn_port_update_sbrec (ovn-northd.c:2981)
> ==22493==    by 0x4112E8: build_ports (ovn-northd.c:3505)
> ==22493==    by 0x42922C: ovnnb_db_run (ovn-northd.c:11138)
> ==22493==    by 0x42A49D: ovn_db_run (ovn-northd.c:11692)
> ==22493==    by 0x42B484: main (ovn-northd.c:12055)
> 
> To fix this we always call ds_destroy(&c_addresses).
> 
> Fixes: 7b1f4dabfb60 ("ovn: Gratuitous ARP for distributed NAT rules")
> Signed-off-by: Dumitru Ceara <dceara at redhat.com>
> ---
>  northd/ovn-northd.c | 1 +
>  1 file changed, 1 insertion(+)
> 
> diff --git a/northd/ovn-northd.c b/northd/ovn-northd.c
> index b25152d..965de05 100644
> --- a/northd/ovn-northd.c
> +++ b/northd/ovn-northd.c
> @@ -2424,6 +2424,7 @@ get_nat_addresses(const struct ovn_port *op, size_t *n)
>      }
>  
>      *n = n_nats;
> +    ds_destroy(&c_addresses);
>  
>      return addresses;
>  }
> 

I'm not sure what this function does exactly, but from the memory usage perspective
this patch looks good to me.

Acked-by: Ilya Maximets <i.maximets at ovn.org>