[PATCH] Fix the kernel panic of audit_filter_task when key field is set

When calling audit_filter_task(), it calls audit_filter_rules() with audit_context is NULL.
If the key field is set, the result in audit_filter_rules() will be set to 1 and
ctx->filterkey will be set to key.
But the ctx is NULL in this condition, so kernel will panic.

Signed-off-by: Zhang Xiliang <zhangxiliang@cn.fujitsu.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

1 files changed, 1 insertions, 1 deletions

diff --git a/kernel/auditsc.c b/kernel/auditsc.c
index 580a5389fd99..496c3dd37276 100644
--- a/kernel/auditsc.c
+++ b/kernel/auditsc.c
@@ -610,7 +610,7 @@ static int audit_filter_rules(struct task_struct *tsk,
                 if (!result)
                         return 0;
         }
-        if (rule->filterkey)
+        if (rule->filterkey && ctx)
                 ctx->filterkey = kstrdup(rule->filterkey, GFP_ATOMIC);
         switch (rule->action) {
         case AUDIT_NEVER:    *state = AUDIT_DISABLED;       break;