5.4-stable review patch. If anyone has any objections, please let me know.
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From: Luiz Augusto von Dentz luiz.von.dentz@intel.com
[ Upstream commit 15bf2c6391bafb14a3020d06ec0761bce0803463 ]
This attempts to detect if HCI_EV_NUM_COMP_PKTS contain an unbalanced (more than currently considered outstanding) number of packets otherwise it could cause the hcon->sent to underflow and loop around breaking the tracking of the outstanding packets pending acknowledgment.
Fixes: f42809185896 ("Bluetooth: Simplify num_comp_pkts_evt function") Signed-off-by: Luiz Augusto von Dentz luiz.von.dentz@intel.com Signed-off-by: Sasha Levin sashal@kernel.org --- net/bluetooth/hci_event.c | 12 +++++++++++- 1 file changed, 11 insertions(+), 1 deletion(-)
diff --git a/net/bluetooth/hci_event.c b/net/bluetooth/hci_event.c index 33b025a52b83a..4e8911501255d 100644 --- a/net/bluetooth/hci_event.c +++ b/net/bluetooth/hci_event.c @@ -3681,7 +3681,17 @@ static void hci_num_comp_pkts_evt(struct hci_dev *hdev, struct sk_buff *skb) if (!conn) continue;
- conn->sent -= count; + /* Check if there is really enough packets outstanding before + * attempting to decrease the sent counter otherwise it could + * underflow.. + */ + if (conn->sent >= count) { + conn->sent -= count; + } else { + bt_dev_warn(hdev, "hcon %p sent %u < count %u", + conn, conn->sent, count); + conn->sent = 0; + }
switch (conn->type) { case ACL_LINK: