keyctl_session_to_parent(): use thread_group_empty() to check singlethreadness

No functional changes.

keyctl_session_to_parent() is the only user of signal->count which needs
the correct value.  Change it to use thread_group_empty() instead, this
must be strictly equivalent under tasklist, and imho looks better.

Signed-off-by: Oleg Nesterov <[email protected]>
Acked-by: David Howells <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Acked-by: Roland McGrath <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>

diff --git a/security/keys/keyctl.c b/security/keys/keyctl.c
index 8f4dce1987c492c59a9e2a6870b1bebaeaac09a8..13074b4547433ab20929fa493114b507c9e4389f 100644 (file)
--- a/security/keys/keyctl.c
+++ b/security/keys/keyctl.c
@@ -1269,7 +1269,7 @@ long keyctl_session_to_parent(void)
                goto not_permitted;
 
        /* the parent must be single threaded */
-       if (atomic_read(&parent->signal->count) != 1)
+       if (!thread_group_empty(parent))
                goto not_permitted;
 
        /* the parent and the child must have different session keyrings or