Bug 190916

Summary:	Allow non root user to remount read-only
Product:	[Fedora] Fedora	Reporter:	Kasper Dupont <bugzilla>
Component:	util-linux	Assignee:	Karel Zak <kzak>
Status:	CLOSED NOTABUG	QA Contact:	Ben Levenson <benl>
Severity:	medium	Docs Contact:
Priority:	medium
Version:	4
Target Milestone:	---
Target Release:	---
Hardware:	All
OS:	Linux
Whiteboard:
Fixed In Version:		Doc Type:	Bug Fix
Doc Text:		Story Points:	---
Clone Of:		Environment:
Last Closed:	2006-08-21 14:57:49 UTC	Type:	---
Regression:	---	Mount Type:	---
Documentation:	---	CRM:
Verified Versions:		Category:	---
oVirt Team:	---	RHEL 7.3 requirements from Atomic Host:
Cloudforms Team:	---	Target Upstream Version:
Embargoed:

Description Kasper Dupont 2006-05-06 13:56:45 UTC

Description of problem:
Non root users cannot remount a file system read-only

Version-Release number of selected component (if applicable):
util-linux-2.12p-9.14

How reproducible:
Always

Steps to Reproduce:
1. mount /media/usbdisk1
2. mount -o remount,ro /media/usbdisk1
  
Actual results:
mount: only root can do that

Expected results:
File system is actually remounted read-only

Additional info:
For a file system which fstab allows the user to mount read-write and unmount,
there seems to be no good reason for dissallowing remounting read-only or
read-write at any time.

Currently "mount --ro /media/usbdisk1" and "mount -r /media/usbdisk1" works as
expected "mount -o ro /media/usbdisk1" does not eventhough the man page say they
are synonymous.

Comment 1 Kasper Dupont 2006-05-06 13:58:12 UTC

This entry should have been marked as a feature-request, for some reason
bugzilla does not seem to allow that anymore.

Comment 2 Karel Zak 2006-08-21 14:57:49 UTC

There's security reason (don't forget we're taking about sbit util). The mount
for non-roots is very limited. You cannot specify (=overwrite fstab) options
like -t, -w, -o, -n, -a, ... You have to follow fstab setting only. And it
doesn't check for -o arguments -- forbidden is arbitrary -o argument. Maybe this
solution is too hard from your point of view, but it's safe and very robust
solution.