From: Hemant Kumar <hema...@codeaurora.org> MHI data completion handler function reads channel id from event ring element. Value is under the control of MHI devices and can be any value between 0 and 255. In order to prevent out of bound access add a bound check against the max channel supported by controller and skip processing of that event ring element.
Signed-off-by: Hemant Kumar <hema...@codeaurora.org> Signed-off-by: Bhaumik Bhatt <bbh...@codeaurora.org> Reviewed-by: Jeffrey Hugo <jh...@codeaurora.org> --- drivers/bus/mhi/core/main.c | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/drivers/bus/mhi/core/main.c b/drivers/bus/mhi/core/main.c index 605640c..e60ab21 100644 --- a/drivers/bus/mhi/core/main.c +++ b/drivers/bus/mhi/core/main.c @@ -776,6 +776,9 @@ int mhi_process_ctrl_ev_ring(struct mhi_controller *mhi_cntrl, case MHI_PKT_TYPE_TX_EVENT: chan = MHI_TRE_GET_EV_CHID(local_rp); mhi_chan = &mhi_cntrl->mhi_chan[chan]; + if (WARN_ON(chan >= mhi_cntrl->max_chan)) + goto next_event; + parse_xfer_event(mhi_cntrl, local_rp, mhi_chan); event_quota--; break; @@ -784,6 +787,7 @@ int mhi_process_ctrl_ev_ring(struct mhi_controller *mhi_cntrl, break; } +next_event: mhi_recycle_ev_ring_element(mhi_cntrl, ev_ring); local_rp = ev_ring->rp; dev_rp = mhi_to_virtual(ev_ring, er_ctxt->rp); @@ -820,6 +824,9 @@ int mhi_process_data_event_ring(struct mhi_controller *mhi_cntrl, enum mhi_pkt_type type = MHI_TRE_GET_EV_TYPE(local_rp); chan = MHI_TRE_GET_EV_CHID(local_rp); + if (WARN_ON(chan >= mhi_cntrl->max_chan)) + goto next_event; + mhi_chan = &mhi_cntrl->mhi_chan[chan]; if (likely(type == MHI_PKT_TYPE_TX_EVENT)) { @@ -830,6 +837,7 @@ int mhi_process_data_event_ring(struct mhi_controller *mhi_cntrl, event_quota--; } +next_event: mhi_recycle_ev_ring_element(mhi_cntrl, ev_ring); local_rp = ev_ring->rp; dev_rp = mhi_to_virtual(ev_ring, er_ctxt->rp); -- The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum, a Linux Foundation Collaborative Project