diff options
| author | Serge Hallyn <serge@hallyn.com> | 2008-02-29 15:14:57 +0000 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2008-03-20 09:46:36 -0700 |
| commit | aedb60a67c10a0861af179725d060765262ba0fb (patch) | |
| tree | 4a4a316f9f7d1ab0bf4da2cdd5c802bfb05c947f /security/capability.c | |
| parent | 457fb605834504af294916411be128a9b21fc3f6 (diff) | |
file capabilities: remove cap_task_kill()
The original justification for cap_task_kill() was as follows:
check_kill_permission() does appropriate uid equivalence checks.
However with file capabilities it becomes possible for an
unprivileged user to execute a file with file capabilities
resulting in a more privileged task with the same uid.
However now that cap_task_kill() always returns 0 (permission
granted) when p->uid==current->uid, the whole hook is worthless,
and only likely to create more subtle problems in the corner cases
where it might still be called but return -EPERM. Those cases
are basically when uids are different but euid/suid is equivalent
as per the check in check_kill_permission().
One example of a still-broken application is 'at' for non-root users.
This patch removes cap_task_kill().
Signed-off-by: Serge Hallyn <serge@hallyn.com>
Acked-by: Andrew G. Morgan <morgan@kernel.org>
Earlier-version-tested-by: Luiz Fernando N. Capitulino <lcapitulino@mandriva.com.br>
Acked-by: Casey Schaufler <casey@schaufler-ca.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'security/capability.c')
| -rw-r--r-- | security/capability.c | 1 |
1 files changed, 0 insertions, 1 deletions
diff --git a/security/capability.c b/security/capability.c index 9e99f36a8b5..2c6e06d18fa 100644 --- a/security/capability.c +++ b/security/capability.c @@ -40,7 +40,6 @@ static struct security_operations capability_ops = { .inode_need_killpriv = cap_inode_need_killpriv, .inode_killpriv = cap_inode_killpriv, - .task_kill = cap_task_kill, .task_setscheduler = cap_task_setscheduler, .task_setioprio = cap_task_setioprio, .task_setnice = cap_task_setnice, |