[PATCH] kmemleak: Never return a pointer you didn't 'get'

From: Phil Carmody
Date: Thu Apr 21 2011 - 07:44:28 EST


Old - If you don't get the last pointer that you looked at, then it will
still be put, as there's no way of knowing you didn't get it.

New - If you didn't get it, then it refers to something deleted, and
your work is done, so return NULL.

Signed-off-by: Phil Carmody <ext-phil.2.carmody@xxxxxxxxx>
---
mm/kmemleak.c | 8 ++++++--
1 files changed, 6 insertions(+), 2 deletions(-)

diff --git a/mm/kmemleak.c b/mm/kmemleak.c
index 8bf765c..3bf204d 100644
--- a/mm/kmemleak.c
+++ b/mm/kmemleak.c
@@ -1350,17 +1350,21 @@ static void *kmemleak_seq_next(struct seq_file *seq, void *v, loff_t *pos)
struct kmemleak_object *prev_obj = v;
struct kmemleak_object *next_obj = NULL;
struct list_head *n = &prev_obj->object_list;
+ int found = 0;

++(*pos);

list_for_each_continue_rcu(n, &object_list) {
next_obj = list_entry(n, struct kmemleak_object, object_list);
- if (get_object(next_obj))
+ if (get_object(next_obj)) {
+ found = 1;
break;
+ }
}

put_object(prev_obj);
- return next_obj;
+
+ return found ? next_obj : NULL;
}

/*
--
1.7.2.rc1.37.gf8c40

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