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Bug 752827 - rss: sigsegv if I'm trying to add second channel without waiting to finish first
rss: sigsegv if I'm trying to add second channel without waiting to finish first
Status: RESOLVED FIXED
Product: libgrss
Classification: Other
Component: General
0.7.x
Other Linux
: High normal
: ---
Assigned To: Libgrss Maintainers
Libgrss Maintainers
Depends on:
Blocks:
 
 
Reported: 2015-07-24 13:34 UTC by Igor Gnatenko
Modified: 2015-07-26 17:41 UTC
See Also:
GNOME target: ---
GNOME version: ---

Attachments
feed-channel: Clear cancellable pointer after cancelling (1012 bytes, patch)
2015-07-26 17:37 UTC, Carlos Garnacho 		committed Details | Review

Description Igor Gnatenko 2015-07-24 13:34:27 UTC 



+
Trace
    235296






Thread 5
          (Thread 0x7fffe5d75700 (LWP 21561))


    

  • 
#0
syscall

    • 

  • 
#1
g_cond_wait_until

    • 

  • 
#2
g_async_queue_pop_intern_unlocked

    • 

  • 
#3
g_async_queue_timeout_pop

    • 

  • 
#4
g_thread_pool_thread_proxy

    • 

  • 
#5
g_thread_proxy

    • 

  • 
#6
start_thread

    • 

  • 
#7
clone

    • 



Thread 1
          (Thread 0x7ffff7f0d900 (LWP 21513))


    

  • 
#0
g_cancellable_cancel

    • 

  • 
#1
grss_feed_channel_fetch_cancel

    
                at feed-channel.c
                  line
                  1277

    

    • 

  • 
#2
cancel_all_pending

    
                at feeds-pool.c
                  line
                  72

    

    • 

  • 
#3
remove_currently_listened

    
                at feeds-pool.c
                  line
                  84

    

    • 

  • 
#4
grss_feeds_pool_listen

    
                at feeds-pool.c
                  line
                  238

    

    • 

  • 
#5
feeds_retrieve_cb

    
                at tracker-miner-rss.c
                  line
                  1190

    

    • 

  • 
#6
g_simple_async_result_complete

    • 

  • 
#7
tracker_sparql_backend_real_query_async_co

    
                at /home/brain/jhbuild/checkout/tracker/src/libtracker-sparql-backend/tracker-backend.vala
                  line
                  108

    

    • 

  • 
#8
g_simple_async_result_complete

    • 

  • 
#9
complete_in_idle_cb

    • 

  • 
#10
g_main_context_dispatch

    • 

  • 
#11
g_main_context_iterate.isra

    • 

  • 
#12
g_main_loop_run

    • 

  • 
#13
main

    
                at tracker-main.c
                  line
                  162

    

    • 









I have not looked into backtrace yet, so probably bug in libgrss






Comment 1


Roberto Guido





          2015-07-25 17:09:51 UTC
        



I can guess the issue is about missing clearing of the GCancellable in grss_feed_channel_fetch_cancel(), but how can I replicate this issue?






Comment 2


Igor Gnatenko





          2015-07-25 17:14:47 UTC
        



(In reply to Roberto Guido from comment #1)
> I can guess the issue is about missing clearing of the GCancellable in
> grss_feed_channel_fetch_cancel(), but how can I replicate this issue?

Run tracker RSS miner from master. Add channel via miner utility, when you see that it fetching feeds - add another  channel. You will see crash.






Comment 3


Igor Gnatenko





          2015-07-25 17:43:49 UTC
        



How do I:
$ tracker reset -r && tracker control -s && killall tracker-miner-rss && ~/jhbuild/install/libexec/tracker-miner-rss -v 3
[snipped]
(tracker-miner-rss:9694): Tracker-DEBUG: Miner:'RSS' noticed store availability has changed to AVAILABLE


In another terminal:
$ ~/jhbuild/install/libexec/tracker-miner-rss -a https://planet.gnome.org/atom.xml

miner gets:
(tracker-miner-rss:9694): Tracker-DEBUG: Indexing channel 'https://planet.gnome.org/atom.xml'
Tracker-Message:   '(null)' (https://planet.gnome.org/atom.xml) - update interval of 20 minutes
Tracker-Message: Retrieving and scheduling feeds...


Again in another terminal (don't wait while grss will fetch items):
$ ~/jhbuild/install/libexec/tracker-miner-rss -a https://planet.fedoraproject.org/atom.xml

miner gets:
(tracker-miner-rss:9694): Tracker-DEBUG: Indexing channel 'https://planet.fedoraproject.org/atom.xml'
Tracker-Message:   '(null)' (https://planet.fedoraproject.org/atom.xml) - update interval of 20 minutes
Segmentation fault (core dumped)






Comment 4


Carlos Garnacho





          2015-07-26 17:37:24 UTC
        



Created attachment 308183 [details] [review]
feed-channel: Clear cancellable pointer after cancelling

Otherwise the pointer will be left pointing to the previous cancellable
location, and crash if we try grss_feed_channel_fetch_all_finish() again,
because it will try to cancel all previous operations first.






Comment 5


Igor Gnatenko





          2015-07-26 17:40:55 UTC
        



Attachment 308183 [details] pushed as 192d664 - feed-channel: Clear cancellable pointer after cancelling