When list_for_each_entry() completes the iteration over the whole list
without breaking the loop, the iterator value will be a bogus pointer
computed based on the head element.
While it is safe to use the pointer to determine if it was computed
based on the head element, either with list_entry_is_head() or
&pos->member == head, using the iterator variable after the loop should
be avoided.
In preparation to limit the scope of a list iterator to the list
traversal loop, use a dedicated pointer to point to the found element [1].
Link: https://lore.kernel.org/all/CAHk-=wgRr_D8CB-D9Kg-c=EHreAsk5SqXPwr9Y7k9sA6cWXJ6w@mail.gmail.com/
Signed-off-by: Jakob Koschel <jakobkoschel@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
struct nitrox_device *nitrox_get_first_device(void)
{
- struct nitrox_device *ndev;
+ struct nitrox_device *ndev = NULL, *iter;
mutex_lock(&devlist_lock);
- list_for_each_entry(ndev, &ndevlist, list) {
- if (nitrox_ready(ndev))
+ list_for_each_entry(iter, &ndevlist, list) {
+ if (nitrox_ready(iter)) {
+ ndev = iter;
break;
+ }
}
mutex_unlock(&devlist_lock);
- if (&ndev->list == &ndevlist)
+ if (!ndev)
return NULL;
refcount_inc(&ndev->refcnt);