After the chroot(), calls to socket() are failing. Why?



After the chroot(), calls to socket() are failing. Why?..

Answer / chaitanya

On systems where sockets are implemented on top of Streams (e.g. all SysV-based systems, presumably including Solaris), the socket() function will actually be opening certain special files in /dev. You will need to create a /dev directory under your fake root and populate it with the required device nodes (only).

Your system documentation may or may not specify exactly which device nodes are required; suggested checking the man page for ftpd, which should list the files you need to copy and devices you need to create in the chroot'd environment.)

A less-obvious issue with chroot() is if you call syslog(), as many daemons do; syslog() opens (depending on the system) either a UDP socket, a FIFO or a Unix-domain socket. So if you use it after a chroot() call, make sure that you call openlog() *before* the chroot.

Is This Answer Correct ?    0 Yes 0 No

Post New Answer

More Unix Socket Programming Interview Questions

How come select says there is data, but read returns zero?

1 Answers  


What is LILO?

2 Answers  


Why do I keep getting EINTR from the socket calls?

1 Answers  


What is the difference between read() and recv()?

0 Answers  


What's the difference between a socket and a port?

0 Answers  






How many socket connections can a server handle?

0 Answers  


What is socket address with example?

0 Answers  


What is the difference between close() and shutdown()?

1 Answers  


When will my application receive SIGPIPE?

1 Answers  


What is with the second parameter in bind()?

1 Answers  


Is a socket a file?

0 Answers  


If bind() fails, what should I do with the socket descriptor?

1 Answers  


Categories