idr: introduce idr_for_each_entry_continue_ul()

Similarly, other callers of idr_get_next_ul() suffer the same
overflow bug as they don't handle it properly either.

Introduce idr_for_each_entry_continue_ul() to help these callers
iterate from a given ID.

cls_flower needs more care here because it still has overflow when
does arg->cookie++, we have to fold its nested loops into one
and remove the arg->cookie++.

Fixes: 01683a1469 ("net: sched: refactor flower walk to iterate over idr")
Fixes: 12d6066c3b ("net/mlx5: Add flow counters idr")
Reported-by: Li Shuang <shuali@redhat.com>
Cc: Davide Caratti <dcaratti@redhat.com>
Cc: Vlad Buslov <vladbu@mellanox.com>
Cc: Chris Mi <chrism@mellanox.com>
Cc: Matthew Wilcox <willy@infradead.org>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Tested-by: Davide Caratti <dcaratti@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Cong Wang 2019-06-28 11:03:42 -07:00 committed by David S. Miller
parent e33d2b74d8
commit d39d714969
3 changed files with 27 additions and 24 deletions

View File

@ -102,13 +102,15 @@ static struct list_head *mlx5_fc_counters_lookup_next(struct mlx5_core_dev *dev,
struct mlx5_fc_stats *fc_stats = &dev->priv.fc_stats;
unsigned long next_id = (unsigned long)id + 1;
struct mlx5_fc *counter;
unsigned long tmp;
rcu_read_lock();
/* skip counters that are in idr, but not yet in counters list */
while ((counter = idr_get_next_ul(&fc_stats->counters_idr,
&next_id)) != NULL &&
list_empty(&counter->list))
next_id++;
idr_for_each_entry_continue_ul(&fc_stats->counters_idr,
counter, tmp, next_id) {
if (!list_empty(&counter->list))
break;
}
rcu_read_unlock();
return counter ? &counter->list : &fc_stats->counters;

View File

@ -216,6 +216,20 @@ static inline void idr_preload_end(void)
entry; \
++id, (entry) = idr_get_next((idr), &(id)))
/**
* idr_for_each_entry_continue_ul() - Continue iteration over an IDR's elements of a given type
* @idr: IDR handle.
* @entry: The type * to use as a cursor.
* @tmp: A temporary placeholder for ID.
* @id: Entry ID.
*
* Continue to iterate over entries, continuing after the current position.
*/
#define idr_for_each_entry_continue_ul(idr, entry, tmp, id) \
for (tmp = id; \
tmp <= id && ((entry) = idr_get_next_ul(idr, &(id))) != NULL; \
tmp = id, ++id)
/*
* IDA - ID Allocator, use when translation from id to pointer isn't necessary.
*/

View File

@ -524,24 +524,6 @@ static struct cls_fl_filter *__fl_get(struct cls_fl_head *head, u32 handle)
return f;
}
static struct cls_fl_filter *fl_get_next_filter(struct tcf_proto *tp,
unsigned long *handle)
{
struct cls_fl_head *head = fl_head_dereference(tp);
struct cls_fl_filter *f;
rcu_read_lock();
while ((f = idr_get_next_ul(&head->handle_idr, handle))) {
/* don't return filters that are being deleted */
if (refcount_inc_not_zero(&f->refcnt))
break;
++(*handle);
}
rcu_read_unlock();
return f;
}
static int __fl_delete(struct tcf_proto *tp, struct cls_fl_filter *f,
bool *last, bool rtnl_held,
struct netlink_ext_ack *extack)
@ -1691,20 +1673,25 @@ static int fl_delete(struct tcf_proto *tp, void *arg, bool *last,
static void fl_walk(struct tcf_proto *tp, struct tcf_walker *arg,
bool rtnl_held)
{
struct cls_fl_head *head = fl_head_dereference(tp);
unsigned long id = arg->cookie, tmp;
struct cls_fl_filter *f;
arg->count = arg->skip;
while ((f = fl_get_next_filter(tp, &arg->cookie)) != NULL) {
idr_for_each_entry_continue_ul(&head->handle_idr, f, tmp, id) {
/* don't return filters that are being deleted */
if (!refcount_inc_not_zero(&f->refcnt))
continue;
if (arg->fn(tp, f, arg) < 0) {
__fl_put(f);
arg->stop = 1;
break;
}
__fl_put(f);
arg->cookie++;
arg->count++;
}
arg->cookie = id;
}
static struct cls_fl_filter *