1
linux/security
Serge Hallyn aedb60a67c 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>
2008-03-20 09:46:36 -07:00
..
keys Convert ERR_PTR(PTR_ERR(p)) instances to ERR_CAST(p) 2008-02-07 08:42:26 -08:00
selinux make selinux_parse_opts_str() static 2008-03-18 09:17:22 +11:00
smack file capabilities: remove cap_task_kill() 2008-03-20 09:46:36 -07:00
capability.c file capabilities: remove cap_task_kill() 2008-03-20 09:46:36 -07:00
commoncap.c file capabilities: remove cap_task_kill() 2008-03-20 09:46:36 -07:00
dummy.c LSM/SELinux: Interfaces to allow FS to control mount options 2008-03-06 08:40:53 +11:00
inode.c Kobject: convert remaining kobject_unregister() to kobject_put() 2008-01-24 20:40:40 -08:00
Kconfig security: allow Kconfig to set default mmap_min_addr protection 2008-02-06 21:39:46 +08:00
Makefile Smack: Simplified Mandatory Access Control Kernel 2008-02-05 09:44:20 -08:00
root_plug.c
security.c LSM/SELinux: Interfaces to allow FS to control mount options 2008-03-06 08:40:53 +11:00