[PATCH] audit: skip sessionid sentinel value when auto-incrementing

[Richard Guy Briggs]

The value (unsigned int)-1 is used as a sentinel to indicate the
sessionID is unset.  Skip this value when the session_id value wraps.

Signed-off-by: Richard Guy Briggs <rgb@xxxxxxxxxx>
---
 kernel/auditsc.c |    5 ++++-
 1 files changed, 4 insertions(+), 1 deletions(-)

diff --git a/kernel/auditsc.c b/kernel/auditsc.c
index 5abf1dc..e414dfa 100644
--- a/kernel/auditsc.c
+++ b/kernel/auditsc.c
@@ -2025,8 +2025,11 @@ int audit_set_loginuid(kuid_t loginuid)
 		goto out;
 
 	/* are we setting or clearing? */
-	if (uid_valid(loginuid))
+	if (uid_valid(loginuid)) {
 		sessionid = (unsigned int)atomic_inc_return(&session_id);
+		if (unlikely(sessionid == (unsigned int)-1))
+			sessionid = (unsigned int)atomic_inc_return(&session_id);
+	}
 
 	task->sessionid = sessionid;
 	task->loginuid = loginuid;
-- 
1.7.1