Commit bd2281b8 authored May 13, 2011 by Julia Lawall Committed by John W. Linville May 16, 2011

net/rfkill/core.c: Avoid leaving freed data in a list

The list_for_each_entry loop can fail, in which case the list element is
not removed from the list rfkill_fds.  Since this list is not accessed by
the loop, the addition of &data->list into the list is just moved after the
loop.

The sematic match that finds this problem is as follows:
(http://coccinelle.lip6.fr/

)

// <smpl>
@@
expression E,E1,E2;
identifier l;
@@

*list_add(&E->l,E1);
... when != E1
    when != list_del(&E->l)
    when != list_del_init(&E->l)
    when != E = E2
*kfree(E);// </smpl>

Signed-off-by: Julia Lawall <julia@diku.dk>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

parent 40b275b6

net/rfkill/core.c

+1 −1

Original line number	Diff line number	Diff line
		@@ -1024,7 +1024,6 @@ static int rfkill_fop_open(struct inode inode, struct file file)
		* start getting events from elsewhere but hold mtx to get
		* startup events added first
		*/
		list_add(&data->list, &rfkill_fds);

		list_for_each_entry(rfkill, &rfkill_list, node) {
		ev = kzalloc(sizeof(*ev), GFP_KERNEL);
		@@ -1033,6 +1032,7 @@ static int rfkill_fop_open(struct inode inode, struct file file)
		rfkill_fill_event(&ev->ev, rfkill, RFKILL_OP_ADD);
		list_add_tail(&ev->list, &data->events);
		}
		list_add(&data->list, &rfkill_fds);
		mutex_unlock(&data->mtx);
		mutex_unlock(&rfkill_global_mutex);

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