setuid

Is there a way to change UID/GID only of one thread in a multithreaded process? The reason for this is writing a file-serving application - the ACL's and quota are not enforced unless the uid/gid of the caller is set to the correct user, new files/directories are not created with correct uid/gid etc. The network applications can usually fork() themselves at the beginning and process each user request in separate process. If there is a need for shared data, it must go through some kind of shared memory. However, e.g. the FUSE (linux user filesystem) by default uses multithreading and in

I have a Perl script that is called either via Apache or on the command-line. For testing purposes, I pass it the username I want the Perl script to operate with, and use POSIX::setuid to set the uid . If I run the script from the command line, then the uid is set properly: use CGI::Pretty qw/:standard/; use POSIX qw(setuid getuid); ... my ($pwName, $pwCode, $pwUid, $pwGid, $pwQuota, $pwComment, $pwGcos, $pwHome, $pwLogprog) = getpwnam($username); if ((defined $pwUid) && (getuid() == $pwUid)) { setuid($pwUid); print header; print Dumper $<; } else { print header(-status => 401); print "Could

I am trying to use LD_PRELOAD to preload a library with an application that has setuid permissions. Tried LD_PRELOAD at first, and it seemed like it was being ignored with the setuid binary, though it was working when I tried it with others like ls , dir etc. From the documentation of LD_PRELOAD: LD_PRELOAD A whitespace-separated list of additional, user-specified, ELF shared libraries to be loaded before all others. This can be used to selectively override functions in other shared libraries. For set- user-ID/set-group-ID ELF binaries, only libraries in the standard search directories that

I'm trying to run sudo, and it's failing: gregd@david $ sudo ls sudo: must be setuid root gregd@david $ which sudo /usr/bin/sudo gregd@david $ ll /usr/bin/sudo -rwxr-xr-x 1 root root 165K 2012-05-16 00:25 /usr/bin/sudo* Any suggestions on how to fix this? Adam This problem is caused sometimes when the permissions of the file, /usr/bin/sudo get set to 777. If you do something like chmod -R 777 /usr/ , you can do this. It effectively ruins sudo. Here is the solution if this is your problem, and the accepted answer doesn't work: To fix: Restart pc, press shift at boot menu. This should bring up

This is a set-root-uid program $ls -l -rwsr-sr-x 1 root root 7406 2011-12-13 22:37 ./x* The source code: int main(void) { printf( " UID GID \n" "Real %d Real %d \n" "Effective %d Effective %d \n", getuid (), getgid (), geteuid(), getegid() ); seteuid(600); printf( " UID GID \n" "Real %d Real %d \n" "Effective %d Effective %d \n", getuid (), getgid (), geteuid(), getegid() ); setuid(1000); printf( " UID GID \n" "Real %d Real %d \n" "Effective %d Effective %d \n", getuid (), getgid (), geteuid(), getegid() ); setuid(0); // HOW DOES THIS SUCCEED IN SETTING THE EUID BACK TO 0 printf( " UID GID \n"

I am running this small python script on both linux and Solaris as a not privileged user : #!/usr/bin/python import os print 'uid,euid =',os.getuid(),os.geteuid() Before running, the setuid bit is set on the script (not on python interpreter) : chown root:myusergrp getuid.py chmod 4750 getuid.py On Solaris, the effective uid is set because of the setuid bit : uid,euid = 10002 0 But not on Linux : uid,euid = 10002 10002 Note the python version is 2.6 for both Solaris and Linux Is it possibe to have Python Linux working as Python Solaris ? Most Unix distributions normally don't allow you to use