From: Vlad Buslov vladbu@nvidia.com
[ Upstream commit fd741f0d9f702c193b2b44225c004f8c5d5be163 ]
When replacing a filter (i.e. 'fold' pointer is not NULL) the insertion of new filter to idr is postponed until later in code since handle is already provided by the user. However, the error handling code in fl_change() always assumes that the new filter had been inserted into idr. If error handler is reached when replacing existing filter it may remove it from idr therefore making it unreachable for delete or dump afterwards. Fix the issue by verifying that 'fold' argument wasn't provided by caller before calling idr_remove().
Fixes: 08a0063df3ae ("net/sched: flower: Move filter handle initialization earlier") Signed-off-by: Vlad Buslov vladbu@nvidia.com Reviewed-by: Pedro Tammela pctammela@mojatatu.com Signed-off-by: David S. Miller davem@davemloft.net Signed-off-by: Sasha Levin sashal@kernel.org --- net/sched/cls_flower.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/net/sched/cls_flower.c b/net/sched/cls_flower.c index d62947eef9727..72edaa6277ce1 100644 --- a/net/sched/cls_flower.c +++ b/net/sched/cls_flower.c @@ -2339,7 +2339,8 @@ static int fl_change(struct net *net, struct sk_buff *in_skb, errout_mask: fl_mask_put(head, fnew->mask); errout_idr: - idr_remove(&head->handle_idr, fnew->handle); + if (!fold) + idr_remove(&head->handle_idr, fnew->handle); __fl_put(fnew); errout_tb: kfree(tb);