From dbf6811abbfcc79d3cd5ce1ff53fe1c741167a1f Mon Sep 17 00:00:00 2001 From: Archie Pusaka Date: Thu, 25 Nov 2021 15:04:37 +0800 Subject: Bluetooth: Limit duration of Remote Name Resolve When doing remote name request, we cannot scan. In the normal case it's OK since we can expect it to finish within a short amount of time. However, there is a possibility to scan lots of devices that (1) requires Remote Name Resolve (2) is unresponsive to Remote Name Resolve When this happens, we are stuck to do Remote Name Resolve until all is done before continue scanning. This patch adds a time limit to stop us spending too long on remote name request. Signed-off-by: Archie Pusaka Reviewed-by: Miao-chen Chou Signed-off-by: Marcel Holtmann --- net/bluetooth/hci_event.c | 7 +++++++ 1 file changed, 7 insertions(+) (limited to 'net/bluetooth') diff --git a/net/bluetooth/hci_event.c b/net/bluetooth/hci_event.c index 324d376f97d4..9d8d2d9e5d1f 100644 --- a/net/bluetooth/hci_event.c +++ b/net/bluetooth/hci_event.c @@ -2129,6 +2129,12 @@ static bool hci_resolve_next_name(struct hci_dev *hdev) if (list_empty(&discov->resolve)) return false; + /* We should stop if we already spent too much time resolving names. */ + if (time_after(jiffies, discov->name_resolve_timeout)) { + bt_dev_warn_ratelimited(hdev, "Name resolve takes too long."); + return false; + } + e = hci_inquiry_cache_lookup_resolve(hdev, BDADDR_ANY, NAME_NEEDED); if (!e) return false; @@ -2716,6 +2722,7 @@ static void hci_inquiry_complete_evt(struct hci_dev *hdev, struct sk_buff *skb) if (e && hci_resolve_name(hdev, e) == 0) { e->name_state = NAME_PENDING; hci_discovery_set_state(hdev, DISCOVERY_RESOLVING); + discov->name_resolve_timeout = jiffies + NAME_RESOLVE_DURATION; } else { /* When BR/EDR inquiry is active and no LE scanning is in * progress, then change discovery state to indicate completion. -- cgit v1.2.3