On Mon, Aug 13, 2012 at 11:10:36AM +0200, Jakub Hrozek wrote:
> On Fri, Aug 10, 2012 at 09:26:49AM +0200, Pavel Březina wrote:
>> On 08/08/2012 04:24 PM, Jakub Hrozek wrote:
>>> On Wed, Aug 08, 2012 at 02:23:04PM +0200, Pavel Březina wrote:
>>>> This bug was probably introduced with the subdomain patches. The
>>>> problem was that sss_dp_get_domains_send() is called even for the local
>>>> provider. There are certainly many possible solutions of this issue. I
>>>> decided to modify sss_dp_issue_request() to call the callback
>>>> immediately if it is issued for local domain. This way, I believe, we
>>>> can avoid further problems with issuing request for local domains.
>>>
>>> I don't think this is the best solution.
>>>
>>> First, it leaves the check_provider of the per-domain structures we use
>>> in responders around while duplicating the same functionality in the DP.
>>> At the very least, the patch should remove the "check_provider"
tests from
>>> the existing loops.
>>>
>>> What I think would be even better solution is to
>>> 1) in the RC just fix the subdomains code so that it shortcuts or
>>> doesn't run at all for LOCAL lookups.
>>
>> Patch is attached.
>
> Thank you, this works for me.
>
> I'm seeing this warning when LOCAL users are enumerated (as opposed to a
> direct lookup):
> (Mon Aug 13 11:06:58 2012) [sssd[nss]] [setent_notify] (0x0010): BUG: a
> callback did not free its request. May leak memory
>
> Given that the LOCAL domain is mostly useful for testing right now, I've
> just filed a ticket:
>
https://fedorahosted.org/sssd/ticket/1477
>
> Ack
Nack, upon further testing. I'm seeing segfaults when looking up
non-LOCAL users:
Core was generated by `/usr/libexec/sssd/sssd_nss -d 0x17f0'.
Program terminated with signal 11, Segmentation fault.
#0 0x000000000043acb1 in get_domains_next (req=0xf95ca0) at
src/responder/common/responder_get_domains.c:124
124 tevent_req_post(req, info->rctx->ev);
Missing separate debuginfos, use: debuginfo-install
nss-softokn-freebl-3.13.5-1.fc17.x86_64 openldap-2.4.31-3.fc17.x86_64
(gdb) bt
#0 0x000000000043acb1 in get_domains_next (req=0xf95ca0) at
src/responder/common/responder_get_domains.c:124
#1 0x000000000043b461 in sss_dp_get_domains_callback (subreq=0xf968b0) at
src/responder/common/responder_get_domains.c:215
#2 0x0000000000439dd4 in sss_dp_internal_get_done (pending=0xf944e0, ptr=0xf99220) at
src/responder/common/responder_dp.c:731
#3 0x000000342fa0c42a in complete_pending_call_and_unlock
(connection=connection@entry=0xf95e40, pending=0xf944e0, message=message@entry=0xf98a80)
at dbus-connection.c:2308
#4 0x000000342fa0f5ea in dbus_connection_dispatch (connection=0xf95e40) at
dbus-connection.c:4593
#5 0x0000000000460432 in sbus_dispatch (ev=0xf89390, te=0xf98bc0, tv=..., data=0xf979a0)
at src/sbus/sssd_dbus_connection.c:104
#6 0x000000385b407600 in tevent_common_loop_timer_delay (ev=ev@entry=0xf89390) at
../tevent_timed.c:254
#7 0x000000385b406cac in std_event_loop_once (ev=0xf89390, location=<optimized
out>) at ../tevent_standard.c:560
#8 0x000000385b403ed0 in _tevent_loop_once (ev=ev@entry=0xf89390,
location=location@entry=0x492f97 "src/util/server.c:554") at ../tevent.c:506
#9 0x000000385b40405b in tevent_common_loop_wait (ev=0xf89390, location=0x492f97
"src/util/server.c:554") at ../tevent.c:607
#10 0x0000000000467bf4 in server_loop (main_ctx=0xf8a4a0) at src/util/server.c:554
#11 0x0000000000408d5c in main (argc=3, argv=0x7fff2dde9cc8) at
src/responder/nss/nsssrv.c:422
(gdb) p *info
$1 = {rctx = 0x3133623833347830, dom = 0x306d61736c3a313a, hint = 0x696e403334346336
<Address 0x696e403334346336 out of bounds>, force = 114, state = 0x0}
It looks like "info" was not initialized.
Thanks.
The problem was that callback is invoked immediately when
tevent_req_done() is called. And because req is freed in this callback,
info was pointing to invalid data.
New patch is attached.