QCA6390 memdump VSE sometimes come to bluetooth driver with wrong sequence number as illustrated as follows: frame # in dec: frame data in hex 1396: ff fd 01 08 74 05 00 37 8f 14 1397: ff fd 01 08 75 05 00 ff bf 38 1414: ff fd 01 08 86 05 00 fb 5e 4b 1399: ff fd 01 08 77 05 00 f3 44 0a 1400: ff fd 01 08 78 05 00 ca f7 41 it is mistook for controller missing packets, so results in page fault after overwriting memdump buffer allocated. Fixed by ignoring QCA6390 sequence number check and checking buffer space before writing. Signed-off-by: Zijun Hu <zijuhu@xxxxxxxxxxxxxx> Tested-by: Zijun Hu <zijuhu@xxxxxxxxxxxxxx> --- Changes in v4: - add a piece of code comments Changes in v3: - correct coding style Changes in v2: - rename a local variable from @temp to @rx_size drivers/bluetooth/hci_qca.c | 49 ++++++++++++++++++++++++++++++++++++++------- 1 file changed, 42 insertions(+), 7 deletions(-) diff --git a/drivers/bluetooth/hci_qca.c b/drivers/bluetooth/hci_qca.c index e4a6823..4acac13 100644 --- a/drivers/bluetooth/hci_qca.c +++ b/drivers/bluetooth/hci_qca.c @@ -114,6 +114,7 @@ struct qca_memdump_data { char *memdump_buf_tail; u32 current_seq_no; u32 received_dump; + u32 ram_dump_size; }; struct qca_memdump_event_hdr { @@ -976,6 +977,8 @@ static void qca_controller_memdump(struct work_struct *work) char nullBuff[QCA_DUMP_PACKET_SIZE] = { 0 }; u16 seq_no; u32 dump_size; + u32 rx_size; + enum qca_btsoc_type soc_type = qca_soc_type(hu); while ((skb = skb_dequeue(&qca->rx_memdump_q))) { @@ -1029,6 +1032,7 @@ static void qca_controller_memdump(struct work_struct *work) skb_pull(skb, sizeof(dump_size)); memdump_buf = vmalloc(dump_size); + qca_memdump->ram_dump_size = dump_size; qca_memdump->memdump_buf_head = memdump_buf; qca_memdump->memdump_buf_tail = memdump_buf; } @@ -1051,26 +1055,57 @@ static void qca_controller_memdump(struct work_struct *work) * the controller. In such cases let us store the dummy * packets in the buffer. */ + /* For QCA6390, controller does not lost packets but + * sequence number field of packat sometimes has error + * bits, so skip this checking for missing packet. + */ while ((seq_no > qca_memdump->current_seq_no + 1) && + (soc_type != QCA_QCA6390) && seq_no != QCA_LAST_SEQUENCE_NUM) { bt_dev_err(hu->hdev, "QCA controller missed packet:%d", qca_memdump->current_seq_no); + rx_size = qca_memdump->received_dump; + rx_size += QCA_DUMP_PACKET_SIZE; + if (rx_size > qca_memdump->ram_dump_size) { + bt_dev_err(hu->hdev, + "QCA memdump received %d, no space for missed packet", + qca_memdump->received_dump); + break; + } memcpy(memdump_buf, nullBuff, QCA_DUMP_PACKET_SIZE); memdump_buf = memdump_buf + QCA_DUMP_PACKET_SIZE; qca_memdump->received_dump += QCA_DUMP_PACKET_SIZE; qca_memdump->current_seq_no++; } - memcpy(memdump_buf, (unsigned char *) skb->data, skb->len); - memdump_buf = memdump_buf + skb->len; - qca_memdump->memdump_buf_tail = memdump_buf; - qca_memdump->current_seq_no = seq_no + 1; - qca_memdump->received_dump += skb->len; + rx_size = qca_memdump->received_dump + skb->len; + if (rx_size <= qca_memdump->ram_dump_size) { + if ((seq_no != QCA_LAST_SEQUENCE_NUM) && + (seq_no != qca_memdump->current_seq_no)) + bt_dev_err(hu->hdev, + "QCA memdump unexpected packet %d", + seq_no); + bt_dev_dbg(hu->hdev, + "QCA memdump packet %d with length %d", + seq_no, skb->len); + memcpy(memdump_buf, (unsigned char *)skb->data, + skb->len); + memdump_buf = memdump_buf + skb->len; + qca_memdump->memdump_buf_tail = memdump_buf; + qca_memdump->current_seq_no = seq_no + 1; + qca_memdump->received_dump += skb->len; + } else { + bt_dev_err(hu->hdev, + "QCA memdump received %d, no space for packet %d", + qca_memdump->received_dump, seq_no); + } qca->qca_memdump = qca_memdump; kfree_skb(skb); if (seq_no == QCA_LAST_SEQUENCE_NUM) { - bt_dev_info(hu->hdev, "QCA writing crash dump of size %d bytes", - qca_memdump->received_dump); + bt_dev_info(hu->hdev, + "QCA memdump Done, received %d, total %d", + qca_memdump->received_dump, + qca_memdump->ram_dump_size); memdump_buf = qca_memdump->memdump_buf_head; dev_coredumpv(&hu->serdev->dev, memdump_buf, qca_memdump->received_dump, GFP_KERNEL); -- The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum, a Linux Foundation Collaborative Project