This bug demonstrates a really nasty problem, with a server that has been through many network reconfiguration so that the kernels ifindex now has reached 37875 ... which never can fit into the statement
> return (HRDEV_NETWORK << HRDEV_TYPE_SHIFT) + HRN_index; (found at line 243 of agent/mibgroup/host/hr_network.c (V5-7-patches) HRDEV_TYPE_SHIFT is only 8, so when ifindex reaches 256 things go astray, and there is no checks in place to detect this. The current crash of snmpd is because HRN_index is a signed short, and the current ifindex value will now turn this into a negative value :-( The server in question has only 8 active network interfaces, but experimentations with network setup (subinterfaces, vlans) makes the ifindex grow when interfaces are removed and re-created This problem is present in all versions from 5.4 and on. I am not sure of the proper solution for this. In all circumstances I think that 255 is a too low limit on network interfaces, and I think that we maybe also should do something to reuse ifindex values if a network interface to deleted and later recreated, which I don't think the kernel will do. Does this warrant a fix for all the current pre and rc releases? /Niels -- Niels Baggesen - @home - Århus - Denmark - n...@users.sourceforge.net The purpose of computing is insight, not numbers --- R W Hamming ------------------------------------------------------------------------------ Live Security Virtual Conference Exclusive live event will cover all the ways today's security and threat landscape has changed and how IT managers can respond. Discussions will include endpoint security, mobile security and the latest in malware threats. http://www.accelacomm.com/jaw/sfrnl04242012/114/50122263/ _______________________________________________ Net-snmp-coders mailing list Net-snmp-coders@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/net-snmp-coders
