umh: creds: convert call_usermodehelper_keys() to use subprocess_info->init()

call_usermodehelper_keys() uses call_usermodehelper_setkeys() to change
subprocess_info->cred in advance.  Now that we have info->init() we can
change this code to set tgcred->session_keyring in context of execing
kernel thread.

Note: since currently call_usermodehelper_keys() is never called with
UMH_NO_WAIT, call_usermodehelper_keys()->key_get() and umh_keys_cleanup()
are not really needed, we could rely on install_session_keyring_to_cred()
which does key_get() on success.

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Acked-by: David Howells <dhowells@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 0 insertions, 18 deletions

diff --git a/kernel/kmod.c b/kernel/kmod.c
index d1544547fea6..743d3883517c 100644
--- a/kernel/kmod.c
+++ b/kernel/kmod.c
@@ -367,24 +367,6 @@ struct subprocess_info *call_usermodehelper_setup(char *path, char **argv,
 EXPORT_SYMBOL(call_usermodehelper_setup);
 
 /**
- * call_usermodehelper_setkeys - set the session keys for usermode helper
- * @info: a subprocess_info returned by call_usermodehelper_setup
- * @session_keyring: the session keyring for the process
- */
-void call_usermodehelper_setkeys(struct subprocess_info *info,
-                                 struct key *session_keyring)
-{
-#ifdef CONFIG_KEYS
-        struct thread_group_cred *tgcred = info->cred->tgcred;
-        key_put(tgcred->session_keyring);
-        tgcred->session_keyring = key_get(session_keyring);
-#else
-        BUG();
-#endif
-}
-EXPORT_SYMBOL(call_usermodehelper_setkeys);
-
-/**
  * call_usermodehelper_setfns - set a cleanup/init function
  * @info: a subprocess_info returned by call_usermodehelper_setup
  * @cleanup: a cleanup function