Re: [PATCH] fixing possible PANIC condition

Hi Stipe,

is it not easier just check for conn !=3D NULL at the place it passed to =
conn_unregister ?
assertion is very interesting at this place IMHO because it can show =
that someone try to unregister connection which is null but should not =
be null.
This prevents from resources leak.

Alex


> Am 10.09.2018 um 12:21 schrieb Stipe Tolj <[email protected]>:
>=20
> Hi list,
>=20
> attached is a patch that fixes a PANIC condition we have been =
reported:
>=20
> 2018-09-07 11:38:07.241 [25148] [9] PANIC: gwlib/conn.c:889: =
conn_unregister: Assertion `conn !=3D NULL' failed.
> 2018-09-07 11:38:07.255 [25148] [9] PANIC: =
/opt/kannel/sbin/smsbox(gw_backtrace+0xbe) [0x44e82e]
> 2018-09-07 11:38:07.255 [25148] [9] PANIC: =
/opt/kannel/sbin/smsbox(gw_panic+0x1ce) [0x44ea0e]
> 2018-09-07 11:38:07.255 [25148] [9] PANIC: /opt/kannel/sbin/smsbox() =
[0x44a21c]
> 2018-09-07 11:38:07.255 [25148] [9] PANIC: /opt/kannel/sbin/smsbox() =
[0x43fba1]
> 2018-09-07 11:38:07.255 [25148] [9] PANIC: /opt/kannel/sbin/smsbox() =
[0x443783]
>=20
> where:
>=20
> # addr2line -e /opt/kannel/sbin/smsbox 0x44a21c 0x43fba1 0x443783
> /tmp/kannel/smppbox-1.9.4/gateway-ha/gwlib/http.c:1213
> /tmp/kannel/smppbox-1.9.4/gateway-ha/gwlib/fdset.c:354
> /tmp/kannel/smppbox-1.9.4/gateway-ha/gwlib/gwthread-pthread.c:165
>=20
> so this was coming from gwlib/http.c:handle_transaction().
>=20
> In fact we DO conn_destroy in gwlib/http.c:/send_request() if a =
conn_write() fails, and then again in handle_transaction() bail out and =
try to conn_unregister() and conn_destroy().
>=20
> The conn_destroy() is safe as it tests for conn =3D=3D NULL, but the =
conn_unregister() would raise an assertion panic here.
>=20
> Suggested patch simply removes the gw_assert() check and leaves it to =
the function to test (what it does) to bail out if the conn is NULL.
>=20
> If no objections arise, will commit to svn trunk.
>=20
> Stipe
>=20
>=20
>=20
> --=20
> Best Regards,
> Stipe Tolj
>=20
> -------------------------------------------------------------------
> D=C3=BCsseldorf, NRW, Germany
>=20
> Kannel Foundation                 tolj.org system architecture
> http://www.kannel.org/            http://www.tolj.org/
>=20
> stolj at kannel.org               st at tolj.org
> -------------------------------------------------------------------
> <workspace-gateway-conn-unreg.diff>