This appears to be a recently introduced kernel bug; I get the root user returned correctly on 2.6.28-6.17, but I can reproduce the error on 2.6.28-7.20.
-- getpwuid fails silently when run as root inside of mlockall() https://bugs.launchpad.net/bugs/329264 You received this bug notification because you are a member of eCryptfs, which is subscribed to ecryptfs-utils in ubuntu. Status in “ecryptfs-utils” source package in Ubuntu: New Status in “glibc” source package in Ubuntu: Confirmed Status in “linux” source package in Ubuntu: New Bug description: Use this test program #include <pwd.h> #include <stdio.h> #include <errno.h> #include <sys/mman.h> int main() { struct passwd *pw = NULL; uid_t id; if (mlockall(MCL_FUTURE)<0) { perror("mlockall"); return 1; } id = getuid(); pw = getpwuid(id); if (pw == NULL) { perror("getpwuid"); return errno; } printf("[%s]\n", pw->pw_name); return 0; } Build on Intrepid, and on Jaunty. Run as root and non-root. r...@jaunty: getpwuid: Success kirkl...@jaunty: getpwuid: Resource temporarily unavailable r...@intrepid: [root] kirkl...@intrepid: getpwuid: Resource temporarily unavailable Running this program as root on intrepid used to work. It does not in Jaunty. Additionally, errno is not set. This regression is breaking mount.ecryptfs, which does a getpwuid() inside of just such an mlock. :-Dustin _______________________________________________ Mailing list: https://launchpad.net/~ecryptfs Post to : [email protected] Unsubscribe : https://launchpad.net/~ecryptfs More help : https://help.launchpad.net/ListHelp
