6.6-stable review patch. If anyone has any objections, please let me know.
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From: En-Wei Wu en-wei.wu@canonical.com
[ Upstream commit 4bcb0c7dc25446b99fc7a8fa2a143d69f3314162 ]
Use skb_pull() and skb_pull_data() to safely parse QCA dump packets.
This avoids direct pointer math on skb->data, which could lead to invalid access if the packet is shorter than expected.
Fixes: 20981ce2d5a5 ("Bluetooth: btusb: Add WCN6855 devcoredump support") Signed-off-by: En-Wei Wu en-wei.wu@canonical.com Signed-off-by: Luiz Augusto von Dentz luiz.von.dentz@intel.com Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/bluetooth/btusb.c | 98 ++++++++++++++++----------------------- 1 file changed, 40 insertions(+), 58 deletions(-)
diff --git a/drivers/bluetooth/btusb.c b/drivers/bluetooth/btusb.c index d6195565ef7ae..e0dd698896088 100644 --- a/drivers/bluetooth/btusb.c +++ b/drivers/bluetooth/btusb.c @@ -3525,9 +3525,8 @@ static void btusb_coredump_qca(struct hci_dev *hdev) static int handle_dump_pkt_qca(struct hci_dev *hdev, struct sk_buff *skb) { int ret = 0; + unsigned int skip = 0; u8 pkt_type; - u8 *sk_ptr; - unsigned int sk_len; u16 seqno; u32 dump_size;
@@ -3536,18 +3535,13 @@ static int handle_dump_pkt_qca(struct hci_dev *hdev, struct sk_buff *skb) struct usb_device *udev = btdata->udev;
pkt_type = hci_skb_pkt_type(skb); - sk_ptr = skb->data; - sk_len = skb->len; + skip = sizeof(struct hci_event_hdr); + if (pkt_type == HCI_ACLDATA_PKT) + skip += sizeof(struct hci_acl_hdr);
- if (pkt_type == HCI_ACLDATA_PKT) { - sk_ptr += HCI_ACL_HDR_SIZE; - sk_len -= HCI_ACL_HDR_SIZE; - } - - sk_ptr += HCI_EVENT_HDR_SIZE; - sk_len -= HCI_EVENT_HDR_SIZE; + skb_pull(skb, skip); + dump_hdr = (struct qca_dump_hdr *)skb->data;
- dump_hdr = (struct qca_dump_hdr *)sk_ptr; seqno = le16_to_cpu(dump_hdr->seqno); if (seqno == 0) { set_bit(BTUSB_HW_SSR_ACTIVE, &btdata->flags); @@ -3567,16 +3561,15 @@ static int handle_dump_pkt_qca(struct hci_dev *hdev, struct sk_buff *skb)
btdata->qca_dump.ram_dump_size = dump_size; btdata->qca_dump.ram_dump_seqno = 0; - sk_ptr += offsetof(struct qca_dump_hdr, data0); - sk_len -= offsetof(struct qca_dump_hdr, data0); + + skb_pull(skb, offsetof(struct qca_dump_hdr, data0));
usb_disable_autosuspend(udev); bt_dev_info(hdev, "%s memdump size(%u)\n", (pkt_type == HCI_ACLDATA_PKT) ? "ACL" : "event", dump_size); } else { - sk_ptr += offsetof(struct qca_dump_hdr, data); - sk_len -= offsetof(struct qca_dump_hdr, data); + skb_pull(skb, offsetof(struct qca_dump_hdr, data)); }
if (!btdata->qca_dump.ram_dump_size) { @@ -3596,7 +3589,6 @@ static int handle_dump_pkt_qca(struct hci_dev *hdev, struct sk_buff *skb) return ret; }
- skb_pull(skb, skb->len - sk_len); hci_devcd_append(hdev, skb); btdata->qca_dump.ram_dump_seqno++; if (seqno == QCA_LAST_SEQUENCE_NUM) { @@ -3624,68 +3616,58 @@ static int handle_dump_pkt_qca(struct hci_dev *hdev, struct sk_buff *skb) /* Return: true if the ACL packet is a dump packet, false otherwise. */ static bool acl_pkt_is_dump_qca(struct hci_dev *hdev, struct sk_buff *skb) { - u8 *sk_ptr; - unsigned int sk_len; - struct hci_event_hdr *event_hdr; struct hci_acl_hdr *acl_hdr; struct qca_dump_hdr *dump_hdr; + struct sk_buff *clone = skb_clone(skb, GFP_ATOMIC); + bool is_dump = false;
- sk_ptr = skb->data; - sk_len = skb->len; - - acl_hdr = hci_acl_hdr(skb); - if (le16_to_cpu(acl_hdr->handle) != QCA_MEMDUMP_ACL_HANDLE) + if (!clone) return false;
- sk_ptr += HCI_ACL_HDR_SIZE; - sk_len -= HCI_ACL_HDR_SIZE; - event_hdr = (struct hci_event_hdr *)sk_ptr; - - if ((event_hdr->evt != HCI_VENDOR_PKT) || - (event_hdr->plen != (sk_len - HCI_EVENT_HDR_SIZE))) - return false; + acl_hdr = skb_pull_data(clone, sizeof(*acl_hdr)); + if (!acl_hdr || (le16_to_cpu(acl_hdr->handle) != QCA_MEMDUMP_ACL_HANDLE)) + goto out;
- sk_ptr += HCI_EVENT_HDR_SIZE; - sk_len -= HCI_EVENT_HDR_SIZE; + event_hdr = skb_pull_data(clone, sizeof(*event_hdr)); + if (!event_hdr || (event_hdr->evt != HCI_VENDOR_PKT)) + goto out;
- dump_hdr = (struct qca_dump_hdr *)sk_ptr; - if ((sk_len < offsetof(struct qca_dump_hdr, data)) || - (dump_hdr->vse_class != QCA_MEMDUMP_VSE_CLASS) || - (dump_hdr->msg_type != QCA_MEMDUMP_MSG_TYPE)) - return false; + dump_hdr = skb_pull_data(clone, sizeof(*dump_hdr)); + if (!dump_hdr || (dump_hdr->vse_class != QCA_MEMDUMP_VSE_CLASS) || + (dump_hdr->msg_type != QCA_MEMDUMP_MSG_TYPE)) + goto out;
- return true; + is_dump = true; +out: + consume_skb(clone); + return is_dump; }
/* Return: true if the event packet is a dump packet, false otherwise. */ static bool evt_pkt_is_dump_qca(struct hci_dev *hdev, struct sk_buff *skb) { - u8 *sk_ptr; - unsigned int sk_len; - struct hci_event_hdr *event_hdr; struct qca_dump_hdr *dump_hdr; + struct sk_buff *clone = skb_clone(skb, GFP_ATOMIC); + bool is_dump = false;
- sk_ptr = skb->data; - sk_len = skb->len; - - event_hdr = hci_event_hdr(skb); - - if ((event_hdr->evt != HCI_VENDOR_PKT) - || (event_hdr->plen != (sk_len - HCI_EVENT_HDR_SIZE))) + if (!clone) return false;
- sk_ptr += HCI_EVENT_HDR_SIZE; - sk_len -= HCI_EVENT_HDR_SIZE; + event_hdr = skb_pull_data(clone, sizeof(*event_hdr)); + if (!event_hdr || (event_hdr->evt != HCI_VENDOR_PKT)) + goto out;
- dump_hdr = (struct qca_dump_hdr *)sk_ptr; - if ((sk_len < offsetof(struct qca_dump_hdr, data)) || - (dump_hdr->vse_class != QCA_MEMDUMP_VSE_CLASS) || - (dump_hdr->msg_type != QCA_MEMDUMP_MSG_TYPE)) - return false; + dump_hdr = skb_pull_data(clone, sizeof(*dump_hdr)); + if (!dump_hdr || (dump_hdr->vse_class != QCA_MEMDUMP_VSE_CLASS) || + (dump_hdr->msg_type != QCA_MEMDUMP_MSG_TYPE)) + goto out;
- return true; + is_dump = true; +out: + consume_skb(clone); + return is_dump; }
static int btusb_recv_acl_qca(struct hci_dev *hdev, struct sk_buff *skb)