On 2022.03.09 13:28, Dr Rainer Woitok wrote:

Greetings,

until recently my system behaves sort of strangely:

$ touch /tmp/file
$ ls -l /tmp/file
-rw------- 1 rainer rainer 0 2022-03-09 19:06 /tmp/file
$ echo x | sudo tee /tmp/file
Password:
tee: /tmp/file: Permission denied
x
$ chmod a+w /tmp/file
$ ls -l /tmp/file
-rw--w--w- 1 rainer rainer 0 2022-03-09 19:06 /tmp/file
$ echo x | sudo tee /tmp/file
tee: /tmp/file: Permission denied
x
$

Since when can't root write to files it doesn't own? And not even,
if
the file has write permission for everybody?

This worked as long as I can think of. My last routine upgrade
install-
ed new kernel package "sys-kernel/gentoo-sources-5.15.26", so I
built
the new kernel and booted from it. May this be the reason?

When I'll have time to reboot, I'll test the above commands on my
old
kernel, 5.15.19. But perhaps there's another reason?

Slightly puzzled
Rainer

Just a gues, but try something like 'sudo -c "echo x | tee /tmp/file"'
or just su first and then do the echo and tee. I think perhaps the permission error is not for root writing to /tmp/file but for the echo
x trying to write to a tee owned by root.

--- SoupGate-Win32 v1.05
* Origin: fsxNet Usenet Gateway (21:1/5)

Greetings,

until recently my system behaves sort of strangely:

$ touch /tmp/file
$ ls -l /tmp/file
-rw------- 1 rainer rainer 0 2022-03-09 19:06 /tmp/file
$ echo x | sudo tee /tmp/file
Password:
tee: /tmp/file: Permission denied
x
$ chmod a+w /tmp/file
$ ls -l /tmp/file
-rw--w--w- 1 rainer rainer 0 2022-03-09 19:06 /tmp/file
$ echo x | sudo tee /tmp/file
tee: /tmp/file: Permission denied
x
$

Since when can't root write to files it doesn't own? And not even, if
the file has write permission for everybody?

This worked as long as I can think of. My last routine upgrade install-
ed new kernel package "sys-kernel/gentoo-sources-5.15.26", so I built
the new kernel and booted from it. May this be the reason?

When I'll have time to reboot, I'll test the above commands on my old kernel, 5.15.19. But perhaps there's another reason?

Slightly puzzled
Rainer

--- SoupGate-Win32 v1.05
* Origin: fsxNet Usenet Gateway (21:1/5)

Rainer,

using sudo does not makes you a root user. To become a root user you have to switch with "su -" (and login with root password).

Sudo has its own configuration file. If you can do something with sudo on other
systems means there is a different configuration for sudo.

Check "man sudo"

Cheers,
Peter


Am Mittwoch, 9. März 2022, 19:28:49 CET schrieb Dr Rainer Woitok:

Greetings,

until recently my system behaves sort of strangely:

$ touch /tmp/file
$ ls -l /tmp/file
-rw------- 1 rainer rainer 0 2022-03-09 19:06 /tmp/file
$ echo x | sudo tee /tmp/file
Password:
tee: /tmp/file: Permission denied
x
$ chmod a+w /tmp/file
$ ls -l /tmp/file
-rw--w--w- 1 rainer rainer 0 2022-03-09 19:06 /tmp/file
$ echo x | sudo tee /tmp/file
tee: /tmp/file: Permission denied
x
$

Since when can't root write to files it doesn't own? And not even, if
the file has write permission for everybody?

This worked as long as I can think of. My last routine upgrade install-
ed new kernel package "sys-kernel/gentoo-sources-5.15.26", so I built
the new kernel and booted from it. May this be the reason?

When I'll have time to reboot, I'll test the above commands on my old kernel, 5.15.19. But perhaps there's another reason?

Slightly puzzled
Rainer

--- SoupGate-Win32 v1.05
* Origin: fsxNet Usenet Gateway (21:1/5)