tcpdump mailing list archives
pcap_compile() causes a segmentation fault on Ubuntu
From: Selçuk Cevher <cevhers () gmail com>
Date: Tue, 14 Dec 2010 11:05:31 +0200
Hi All, The following code fragment causes a segmentation fault in Ubuntu when pcap_compile() is executed in setupFilterExpression(): *int main() { char errbuf[PCAP_ERRBUF_SIZE]; vector<string> devNames; listAllDevices(devNames, errbuf);//list the device names pcap_t* handle;//sniffing session handle bpf_u_int32 netMask;//net mask of the device to be opened bpf_u_int32 ipAddress;//ip address of the device to be opened openNetworkDevice(handle, devNames, &netMask, &ipAddress, errbuf);//open the device for sniffing string exp("ip"); struct bpf_program fp;//the compiled filter expression if( setupFilterExpression(handle, exp, &fp, netMask) == -1 )//set up filter expression for packets { cout << "Could not set up filter expression" << endl; return(-1); } return(0); }* *int setupFilterExpression(pcap_t* handle, string exp, struct bpf_program* fp, bpf_u_int32& netMask) { if(pcap_compile(handle, fp, exp.c_str(), 0, netMask) == -1) <<<<<<-------------- segmentation fault { cout << "Couldn't parse filter " << exp << ":" << pcap_geterr(handle) <<endl; return -1; } if(pcap_setfilter(handle, fp) == -1) { cout << "Couldn't install filter " << exp << ":" << pcap_geterr(handle) <<endl; return -1; } cout << "Succesfull setup of filter expression: " << exp << endl; return 0; }* If you need to see the sources for listAllDevices() and openNetworkDevice() as well, I can post them. What may cause pcap_compile() to crash ? I am using Ubuntu 10.04, and, as far as I know, this filtering mechanism may not be supported in some kernels. Thanks. - This is the tcpdump-workers list. Visit https://cod.sandelman.ca/ to unsubscribe.
Current thread:
- pcap_compile() causes a segmentation fault on Ubuntu Selçuk Cevher (Dec 14)
- Re: pcap_compile() causes a segmentation fault on Ubuntu Guy Harris (Dec 14)
- Re: pcap_compile() causes a segmentation fault on Ubuntu Selçuk Cevher (Dec 14)
- Re: pcap_compile() causes a segmentation fault on Ubuntu Guy Harris (Dec 14)