Messages in this thread | ![/](/images/icornerl.gif) | | Date | Wed, 16 Jul 2003 10:19:14 -0400 (EDT) | From | "Richard B. Johnson" <> | Subject | SUID root |
| |
It appears as though SUID root programs don't work on linux 2.4.20, 2.4.21, or 2.4.22-pre6, or at least what used to work no longer does.
One program tries to execute iopl(3). In the event that it fails, it tries to set UID/GID to root after saving the previous, then tries again.
The program exists in /usr/bin, properly owned by root. It is set SUID, 4755, and otherwise works. Anybody have any clues? Do SUID programs have to be re-written to use some other mechanism? I need to have a user-mode program get access to an otherwise unused printer port. It's a shame to write a module just for this.
brk(0x804f000) = 0x804f000 brk(0x8051000) = 0x8051000 brk(0x8053000) = 0x8053000 time(NULL) = 1058364273 iopl(0x3) = -1 EPERM (Operation not permitted) getuid() = 100 getgid() = 100 setuid(0) = -1 EPERM (Operation not permitted) setgid(0) = -1 EPERM (Operation not permitted) iopl(0x3) = -1 EPERM (Operation not permitted) _exit(0) = ? $ ls -la /usr/bin/debug -rwsr-xr-x 1 root root 6126 Jul 16 09:59 /usr/bin/debug $ exit exit
Script done on Wed Jul 16 10:05:02 2003
Cheers, Dick Johnson Penguin : Linux version 2.4.20 on an i686 machine (797.90 BogoMips). Note 96.3% of all statistics are fiction.
- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
| ![\](/images/icornerr.gif) |