[RFC PATCH 20/21] selinux: Implement the watch_key security hook
From: David Howells <dhowells@redhat.com>
Date: 2019-10-15 21:50:58
Also in:
keyrings, linux-block, linux-fsdevel, linux-security-module, linux-usb, lkml
Subsystem:
selinux security module, the rest · Maintainers:
Paul Moore, Stephen Smalley, Linus Torvalds
Implement the watch_key security hook to make sure that a key grants the caller View permission in order to set a watch on a key. For the moment, the watch_devices security hook is left unimplemented as it's not obvious what the object should be since the queue is global and didn't previously exist. Signed-off-by: David Howells <dhowells@redhat.com> Acked-by: Stephen Smalley <redacted> --- security/selinux/hooks.c | 14 ++++++++++++++ 1 file changed, 14 insertions(+)
diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c
index 9625b99e677f..53637dccee00 100644
--- a/security/selinux/hooks.c
+++ b/security/selinux/hooks.c@@ -6579,6 +6579,17 @@ static int selinux_key_getsecurity(struct key *key, char **_buffer) *_buffer = context; return rc; } + +#ifdef CONFIG_KEY_NOTIFICATIONS +static int selinux_watch_key(struct key *key) +{ + struct key_security_struct *ksec = key->security; + u32 sid = current_sid(); + + return avc_has_perm(&selinux_state, + sid, ksec->sid, SECCLASS_KEY, KEY_NEED_VIEW, NULL); +} +#endif #endif #ifdef CONFIG_SECURITY_INFINIBAND
@@ -7012,6 +7023,9 @@ static struct security_hook_list selinux_hooks[] __lsm_ro_after_init = { LSM_HOOK_INIT(key_free, selinux_key_free), LSM_HOOK_INIT(key_permission, selinux_key_permission), LSM_HOOK_INIT(key_getsecurity, selinux_key_getsecurity), +#ifdef CONFIG_KEY_NOTIFICATIONS + LSM_HOOK_INIT(watch_key, selinux_watch_key), +#endif #endif #ifdef CONFIG_AUDIT