From 7db68b2c5dec2ad770e578bc279e73166e1b08e0 Mon Sep 17 00:00:00 2001 From: Wish Wu Date: Fri, 15 Jan 2016 20:03:14 -0500 Subject: msm: null pointer dereferencing Prevent unintended kernel NULL pointer dereferencing. Orignal code: hlist_del_rcu(&event->hlist_entry); Fix: Adding pointer check: if(!hlist_unhashed(&p_event->hlist_entry)) hlist_del_rcu(&p_event->hlist_entry); Bug: 25364034 Change-Id: Ieda6d8f4bb567827fa6c7709e9e729905c6c3882 Signed-off-by: Yuan Lin --- kernel/trace/trace_event_perf.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) (limited to 'kernel/trace/trace_event_perf.c') diff --git a/kernel/trace/trace_event_perf.c b/kernel/trace/trace_event_perf.c index 8354dc81a..4025c6034 100644 --- a/kernel/trace/trace_event_perf.c +++ b/kernel/trace/trace_event_perf.c @@ -222,7 +222,10 @@ int perf_trace_add(struct perf_event *p_event, int flags) void perf_trace_del(struct perf_event *p_event, int flags) { struct ftrace_event_call *tp_event = p_event->tp_event; - hlist_del_rcu(&p_event->hlist_entry); + if(!hlist_unhashed(&p_event->hlist_entry)) + hlist_del_rcu(&p_event->hlist_entry); + else + return; tp_event->class->reg(tp_event, TRACE_REG_PERF_DEL, p_event); } -- cgit v1.2.3