Kernel/linux-next
1
0
Fork 0
mirror of https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git synced 2024-12-28 16:52:18 +00:00
Code Issues Actions Packages Projects Releases Wiki Activity

gfs2: reorder capability check last

Browse Source 
capable() calls refer to enabled LSMs whether to permit or deny the
request.  This is relevant in connection with SELinux, where a
capability check results in a policy decision and by default a denial
message on insufficient permission is issued.
It can lead to three undesired cases:
  1. A denial message is generated, even in case the operation was an
     unprivileged one and thus the syscall succeeded, creating noise.
  2. To avoid the noise from 1. the policy writer adds a rule to ignore
     those denial messages, hiding future syscalls, where the task
     performs an actual privileged operation, leading to hidden limited
     functionality of that task.
  3. To avoid the noise from 1. the policy writer adds a rule to permit
     the task the requested capability, while it does not need it,
     violating the principle of least privilege.

Signed-off-by: Christian Göttsche <cgzones@googlemail.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
This commit is contained in:
Christian Göttsche 2024-11-25 11:40:00 +01:00 committed by Andreas Gruenbacher
parent ff2a7a064a
commit ead64b20f1
1 changed files with 2 additions and 2 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

4
fs/gfs2/quota.h
View File

@ -44,8 +44,8 @@ static inline int gfs2_quota_lock_check(struct gfs2_inode *ip,
int ret;
ap->allowed = UINT_MAX; /* Assume we are permitted a whole lot */
if (capable(CAP_SYS_RESOURCE) ||
sdp->sd_args.ar_quota == GFS2_QUOTA_OFF)
if (sdp->sd_args.ar_quota == GFS2_QUOTA_OFF ||
capable(CAP_SYS_RESOURCE))
return 0;
ret = gfs2_quota_lock(ip, NO_UID_QUOTA_CHANGE, NO_GID_QUOTA_CHANGE);
if (ret)