From ee6cdabc820a29bd607f38d9cb335c3ceddc673b Mon Sep 17 00:00:00 2001 From: Tom Zanussi Date: Mon, 23 Mar 2009 03:26:42 -0500 Subject: [PATCH] tracing/filters: fix bug in copy_pred() Impact: fix potential crash on subsystem filter expression freeing When making a copy of the predicate, pred->field_name needs to be duplicated in the copy as well, otherwise bad things can happen due to later multiple frees of the same string. This affects only per-subsystem event filtering. Signed-off-by: Tom Zanussi Cc: Steven Rostedt Cc: =?ISO-8859-1?Q?Fr=E9d=E9ric?= Weisbecker LKML-Reference: <1237796802.7527.39.camel@charm-linux> Signed-off-by: Ingo Molnar --- kernel/trace/trace_events_filter.c | 12 ++++++++++-- 1 file changed, 10 insertions(+), 2 deletions(-) diff --git a/kernel/trace/trace_events_filter.c b/kernel/trace/trace_events_filter.c index c4a413b70f7..fd01d8022ad 100644 --- a/kernel/trace/trace_events_filter.c +++ b/kernel/trace/trace_events_filter.c @@ -276,11 +276,19 @@ static struct filter_pred *copy_pred(struct filter_pred *pred) return NULL; memcpy(new_pred, pred, sizeof(*pred)); + + if (pred->field_name) { + new_pred->field_name = kstrdup(pred->field_name, GFP_KERNEL); + if (!new_pred->field_name) { + kfree(new_pred); + return NULL; + } + } + if (pred->str_val) { new_pred->str_val = kstrdup(pred->str_val, GFP_KERNEL); - new_pred->field_name = kstrdup(pred->field_name, GFP_KERNEL); if (!new_pred->str_val) { - kfree(new_pred); + filter_free_pred(new_pred); return NULL; } } -- 2.41.1