Messages in this thread Patch in this message | | | Date | Tue, 3 Apr 2012 02:06:56 +0300 | From | Sergey Senozhatsky <> | Subject | [PATCH] kmemleak: do not leak object after tree insertion error (v2, fixed) |
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[PATCH] kmemleak: do not leak object after tree insertion error
In case when tree insertion fails due to already existing object error, pointer to allocated object gets lost due to lookup_object() overwrite. Free allocated object and return the existing one, obtained from lookup_object().
Signed-off-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
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mm/kmemleak.c | 19 ++++++++++++------- 1 file changed, 12 insertions(+), 7 deletions(-)
diff --git a/mm/kmemleak.c b/mm/kmemleak.c index 45eb621..4177d83 100644 --- a/mm/kmemleak.c +++ b/mm/kmemleak.c @@ -516,7 +516,7 @@ static struct kmemleak_object *create_object(unsigned long ptr, size_t size, int min_count, gfp_t gfp) { unsigned long flags; - struct kmemleak_object *object; + struct kmemleak_object *object, *ex_object; struct prio_tree_node *node; object = kmem_cache_alloc(object_cache, gfp_kmemleak_mask(gfp)); @@ -578,17 +578,22 @@ static struct kmemleak_object *create_object(unsigned long ptr, size_t size, if (node != &object->tree_node) { kmemleak_stop("Cannot insert 0x%lx into the object search tree " "(already existing)\n", ptr); - object = lookup_object(ptr, 1); - spin_lock(&object->lock); - dump_object_info(object); - spin_unlock(&object->lock); + ex_object = lookup_object(ptr, 1); + spin_lock(&ex_object->lock); + dump_object_info(ex_object); + spin_unlock(&ex_object->lock); - goto out; + goto out_error; } list_add_tail_rcu(&object->object_list, &object_list); -out: + write_unlock_irqrestore(&kmemleak_lock, flags); return object; +out_error: + write_unlock_irqrestore(&kmemleak_lock, flags); + object->flags &= ~OBJECT_ALLOCATED; + put_object(object); + return ex_object; } /*
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