#2 Buffer overflow after 3k simultaneous connection

[Florent]

I'm running a test where I want to benchmark 20k simulataneaous connection.
I run it like that :

• iperf -s -u
• iper-c IP -u -b 12 -t TIME

After 3657 connection, it dosn't accept anyone anymore, and then when the test end, after 1026 disconnection it crashes

[1016]  0.0-3601.7 sec  4.64 MBytes  10.8 Kbits/sec   0.000 ms  368/ 3675 (0%)
[1026]  0.0-3601.0 sec  4.71 MBytes  11.0 Kbits/sec   0.000 ms  318/ 3675 (0%)
*** buffer overflow detected ***: ./iperf terminated
======= Backtrace: =========
/lib/x86_64-linux-gnu/libc.so.6(+0x7338f)[0x7f55a87c038f]
/lib/x86_64-linux-gnu/libc.so.6(__fortify_fail+0x5c)[0x7f55a8857c9c]
/lib/x86_64-linux-gnu/libc.so.6(+0x109b60)[0x7f55a8856b60]
/lib/x86_64-linux-gnu/libc.so.6(+0x10abe7)[0x7f55a8857be7]
./iperf[0x408dd8]
./iperf[0x409640]
./iperf[0x403be9]
./iperf[0x40caea]
/lib/x86_64-linux-gnu/libpthread.so.0(+0x8182)[0x7f55a8b1a182]
/lib/x86_64-linux-gnu/libc.so.6(clone+0x6d)[0x7f55a884747d]
======= Memory map: ========
00400000-00413000 r-xp 00000000 ca:01 277584                             /home/ubuntu/iperf2-codenew/src/iperf
00612000-00613000 r--p 00012000 ca:01 277584                             /home/ubuntu/iperf2-codenew/src/iperf
00613000-00614000 rw-p 00013000 ca:01 277584                             /home/ubuntu/iperf2-codenew/src/iperf
01cf0000-01d32000 rw-p 00000000 00:00 0                                  [heap]

I compiled myself the latest code from git (commit 3409672f34f73375047cc17dd5b0ca36d7f95036)

I got the same bahovior from the standard version from my ubuntu box (iperf 2.0.5-3)

Please find attached the complete log

[Florent]

I also have some info about the core dump (but for the standard ubuntu version 2.0.5-3)

[Robert McMahon]

Thanks for reporting this. I'll try to reproduce soon and my have some questions.