Red Hat Bugzilla – Bug 232565
immediate disconnect from Red Hat VPN
Last modified: 2007-11-30 17:11:59 EST
Description of problem:
I haven't been able to get into the Red Hat vpn using vpnc-0.4.0-1.fc7. The
vpnc executable from vpnc-0.3.3-13.fc6 works like a charm.
I run as root vpnc --ifname tun0 /name/of/config.file
where config.file contains stuff such as:
IPsec gateway <snipped> (the RDU gateway)
IPsec ID <snipped>
IPsec secret <snipped>
Xauth username <snipped>
# Rekeying interval 7200
Version-Release number of selected component (if applicable):
Steps to Reproduce:
1.Start vpnc with --no-detach, as above
2.Enter the password
Shortly after displaying the banner, it quits.
It's behind NAT, which works fine with the older release. Apparently it sends a
packet after S7.10, and receives a response to the effect that it should quit,
so it prints S8, logs "connection terminated by peer" and quits.
It seems like the x86_64 compilation bug is back. Can you try to recompile the
src.rpm without -fstack-protector whether it helps?
Yes. Compiling without -fstack-protector on x86_64 makes this bug vanish (poof!).
It was caused by a bug in vpnc. It was overwriting a value on stack because of
wrong sizeof() call. The -fstack-protector caused reordering the values on the
stack so an important value was overwritten without the option the overwrite was
harmless so the code worked.