Custom Query (89 matches)

Kindly advise me how to remove invald free in execution of libtrace functions

If the change in r1681 is reverted, libtrace can segfault when reading traces on certain systems.

This appears to be due to a threading issue where the value of the len parameter passed into thread_read() is changed by another thread. This is in spite of the parameter being passed in by value rather than reference, as gcc appears to be optimising this parameter into a pass by reference. Disabling optimisations will prevent the problem from occurring.

The solution in r1681 is only treating the symptom, not the actual problem, so it would be good if we can find the point where the other thread touches something it shouldn't and put a mutex around it.

I've been able to replicate this on an Ubuntu 9.10 box using gcc 4.4.1 (for WAND folks, this is laptop "druid").

Trying to run tracepktdump on the Wireless 1 trace results in the following output:

tracepktdump -c 1 pcapfile:/trace/wireless/1/wireless-i.pcap.gz 

Fri Mar  7 22:52:16 2008
 Capture: Packet Length: 178/178 Direction Value: 1
 Linux SLL: Packet Type = HOST
 Linux SLL: Hardware Address Type = 0x0323
 Linux SLL: Hardware Address Length = 6
 Linux SLL: Hardware Address = 00:00:02:7b:c4:7f
 Linux SLL: Protocol = 0x0019
tracepktdump: symbol lookup error: /home/salcock/install//lib/libpacketdump/link_6.so: undefined symbol: arphrd_type_to_libtrace

arphrd_type_to_libtrace is only defined locally within the libtrace library. The question is: do we want to make this an external function so that link_6.c can use it, or should we just copy and paste the code for that function into link_6.c and hope we never have to change it?