Re: [expert] Wierd unmount only permitted as root
Hi, Thanks for the reply. after making it suid root it still said you need to be root to unmount perhaps there is something else stopping it working that we don't know. Strange how it works in redhat. Regards JG Dave Sherman wrote: On Mon, 2002-12-16 at 21:35, J. Grant wrote: Hi Dave, I am surprised that works, here chmod +s only gives user and group +s so my normal user can still not run it. Any other ideas? I could use a script, but there must be something more elegant Regards JG Here are the relevant permissions on /usr/bin/smb* (RedHat 8.0, remember): -rwsr-sr-x1 root root 548K Nov 20 11:18 /usr/bin/smbmnt -rwxr-xr-x1 root root 558K Nov 20 11:18 /usr/bin/smbmount -rwsr-sr-x1 root root 547K Nov 20 11:18 /usr/bin/smbumount Notice that smbmount does not have the setuid (sticky) bit set, because it really just calls smbmnt anyway. The only one I have to change was smbumount, the others were already set. Now, here are my /bin/mount and /bin/umount perms: -rwsr-xr-x1 root root 80K Aug 30 15:00 /bin/mount -rwsr-xr-x1 root root 40K Aug 30 15:00 /bin/umount Neither of these have been changed from their defaults. Notice that root is both owner/user and group, as I assume they are on your Mandrake system. But with the sticky bit set (the 'chmod +s' trick), this causes the program to run with the permissions of the owner and/or group, whichever bit is set. So a user can run these programs, but the program actually runs with root authority, not just the user's authority. That's why I said this isn't a secure solution, but it works on my single-user laptop. If, after trying 'chmod +s umount', you still can't use umount -- well, I guess I really don't know why. Do you get any specific error messages, like maybe the command 'umount' is not found? Perhaps it simply isn't in your $PATH, but it is in root's $PATH. The error I originally got indicated that only root had permission to smbumount network filesystems. Thus, I fixed it by making it setuid root. Dave Dave Sherman wrote: On Sun, 2002-12-15 at 12:07, J. Grant wrote: Hi, I'm seeing some strange effects, this has been going on for a while, but i've not got around to asking if there is a solution, basically, even though I have user in my fstab I can only unmount my cdrom as root. Any ideas or solutions? I ran into a similar problem with RedHat 8.0 and Samba (couldn't unmount a share as a user, even though I had mounted the share as the same user), my solution was to (as root): # chmod +s /usr/bin/smbumount I would think your solution would be to check /bin/mount and /bin/umount, and try the same thing on umount. This is not a secure solution, but it works on my (single-user) laptop. Want to buy your Pack or Services from MandrakeSoft? Go to http://www.mandrakestore.com
Re: [expert] Wierd unmount only permitted as root
On Tue, 2002-12-17 at 07:44, J. Grant wrote: Hi, Thanks for the reply. after making it suid root it still said you need to be root to unmount perhaps there is something else stopping it working that we don't know. Strange how it works in redhat. How about you post the line in your /etc/fstab file? Then we can compare it to mine or someone else's and see if there is a difference. Here's mine: /dev/cdrom /mnt/cdrom iso9660 noauto,owner,kudzu,ro 0 0 -- Dave Sherman MCSE, MCSA, CCNA If we wanted you to understand it, we wouldn't call it code. signature.asc Description: This is a digitally signed message part
Re: [expert] Wierd unmount only permitted as root
This is from my desktop, i disabled supermount /dev/scd0 /mnt/cdrom iso9660 user,iocharset=iso8859-15,codepage=850,noauto,umask=0 0 0 /dev/hda /mnt/cdrom2 iso9660 user,iocharset=iso8859-15,codepage=850,noauto,umask=0 0 0 from my other machine with supermount none /mnt/cdrom supermount dev=/dev/hdc,fs=auto,ro,--,umask=0,codepage=850,iocharset=iso8859-15,user 0 0 Both can only be unmounted by root normlaly. Occasionally the fomer lets me unmount as a normal user i think. I just changed to users so that any user can unmount, and it works! I guess its because the fs was mounted by root at startup Regards JG Dave Sherman wrote: On Tue, 2002-12-17 at 07:44, J. Grant wrote: Hi, Thanks for the reply. after making it suid root it still said you need to be root to unmount perhaps there is something else stopping it working that we don't know. Strange how it works in redhat. How about you post the line in your /etc/fstab file? Then we can compare it to mine or someone else's and see if there is a difference. Here's mine: /dev/cdrom /mnt/cdrom iso9660 noauto,owner,kudzu,ro 0 0 Want to buy your Pack or Services from MandrakeSoft? Go to http://www.mandrakestore.com
Re: [expert] Wierd unmount only permitted as root
Hi Dave, I am surprised that works, here chmod +s only gives user and group +s so my normal user can still not run it. Any other ideas? I could use a script, but there must be something more elegant Regards JG Dave Sherman wrote: On Sun, 2002-12-15 at 12:07, J. Grant wrote: Hi, I'm seeing some strange effects, this has been going on for a while, but i've not got around to asking if there is a solution, basically, even though I have user in my fstab I can only unmount my cdrom as root. Any ideas or solutions? I ran into a similar problem with RedHat 8.0 and Samba (couldn't unmount a share as a user, even though I had mounted the share as the same user), my solution was to (as root): # chmod +s /usr/bin/smbumount I would think your solution would be to check /bin/mount and /bin/umount, and try the same thing on umount. This is not a secure solution, but it works on my (single-user) laptop. Want to buy your Pack or Services from MandrakeSoft? Go to http://www.mandrakestore.com
Re: [expert] Wierd unmount only permitted as root
On Mon, 2002-12-16 at 21:35, J. Grant wrote: Hi Dave, I am surprised that works, here chmod +s only gives user and group +s so my normal user can still not run it. Any other ideas? I could use a script, but there must be something more elegant Regards JG Here are the relevant permissions on /usr/bin/smb* (RedHat 8.0, remember): -rwsr-sr-x1 root root 548K Nov 20 11:18 /usr/bin/smbmnt -rwxr-xr-x1 root root 558K Nov 20 11:18 /usr/bin/smbmount -rwsr-sr-x1 root root 547K Nov 20 11:18 /usr/bin/smbumount Notice that smbmount does not have the setuid (sticky) bit set, because it really just calls smbmnt anyway. The only one I have to change was smbumount, the others were already set. Now, here are my /bin/mount and /bin/umount perms: -rwsr-xr-x1 root root 80K Aug 30 15:00 /bin/mount -rwsr-xr-x1 root root 40K Aug 30 15:00 /bin/umount Neither of these have been changed from their defaults. Notice that root is both owner/user and group, as I assume they are on your Mandrake system. But with the sticky bit set (the 'chmod +s' trick), this causes the program to run with the permissions of the owner and/or group, whichever bit is set. So a user can run these programs, but the program actually runs with root authority, not just the user's authority. That's why I said this isn't a secure solution, but it works on my single-user laptop. If, after trying 'chmod +s umount', you still can't use umount -- well, I guess I really don't know why. Do you get any specific error messages, like maybe the command 'umount' is not found? Perhaps it simply isn't in your $PATH, but it is in root's $PATH. The error I originally got indicated that only root had permission to smbumount network filesystems. Thus, I fixed it by making it setuid root. Dave Dave Sherman wrote: On Sun, 2002-12-15 at 12:07, J. Grant wrote: Hi, I'm seeing some strange effects, this has been going on for a while, but i've not got around to asking if there is a solution, basically, even though I have user in my fstab I can only unmount my cdrom as root. Any ideas or solutions? I ran into a similar problem with RedHat 8.0 and Samba (couldn't unmount a share as a user, even though I had mounted the share as the same user), my solution was to (as root): # chmod +s /usr/bin/smbumount I would think your solution would be to check /bin/mount and /bin/umount, and try the same thing on umount. This is not a secure solution, but it works on my (single-user) laptop. -- Dave Sherman MCSE, MCSA, CCNA If we wanted you to understand it, we wouldn't call it code. signature.asc Description: This is a digitally signed message part
Re: [expert] Wierd unmount only permitted as root
On Sun, 2002-12-15 at 12:07, J. Grant wrote: Hi, I'm seeing some strange effects, this has been going on for a while, but i've not got around to asking if there is a solution, basically, even though I have user in my fstab I can only unmount my cdrom as root. Any ideas or solutions? I ran into a similar problem with RedHat 8.0 and Samba (couldn't unmount a share as a user, even though I had mounted the share as the same user), my solution was to (as root): # chmod +s /usr/bin/smbumount I would think your solution would be to check /bin/mount and /bin/umount, and try the same thing on umount. This is not a secure solution, but it works on my (single-user) laptop. -- Dave Sherman MCSE, MCSA, CCNA If we wanted you to understand it, we wouldn't call it code. signature.asc Description: This is a digitally signed message part
