From 6a0c637bfee69a74c104468544d9f2a6579626d0 Mon Sep 17 00:00:00 2001 From: Jeffrey Hugo Date: Fri, 24 Mar 2023 10:13:04 -0600 Subject: bus: mhi: host: Range check CHDBOFF and ERDBOFF If the value read from the CHDBOFF and ERDBOFF registers is outside the range of the MHI register space then an invalid address might be computed which later causes a kernel panic. Range check the read value to prevent a crash due to bad data from the device. Fixes: 6cd330ae76ff ("bus: mhi: core: Add support for ringing channel/event ring doorbells") Cc: stable@vger.kernel.org Signed-off-by: Jeffrey Hugo Reviewed-by: Pranjal Ramajor Asha Kanojiya Reviewed-by: Manivannan Sadhasivam Link: https://lore.kernel.org/r/1679674384-27209-1-git-send-email-quic_jhugo@quicinc.com Signed-off-by: Manivannan Sadhasivam --- drivers/bus/mhi/host/init.c | 12 ++++++++++++ 1 file changed, 12 insertions(+) (limited to 'drivers/bus/mhi') diff --git a/drivers/bus/mhi/host/init.c b/drivers/bus/mhi/host/init.c index 3d779ee6396d..b46a0821adf9 100644 --- a/drivers/bus/mhi/host/init.c +++ b/drivers/bus/mhi/host/init.c @@ -516,6 +516,12 @@ int mhi_init_mmio(struct mhi_controller *mhi_cntrl) return -EIO; } + if (val >= mhi_cntrl->reg_len - (8 * MHI_DEV_WAKE_DB)) { + dev_err(dev, "CHDB offset: 0x%x is out of range: 0x%zx\n", + val, mhi_cntrl->reg_len - (8 * MHI_DEV_WAKE_DB)); + return -ERANGE; + } + /* Setup wake db */ mhi_cntrl->wake_db = base + val + (8 * MHI_DEV_WAKE_DB); mhi_cntrl->wake_set = false; @@ -532,6 +538,12 @@ int mhi_init_mmio(struct mhi_controller *mhi_cntrl) return -EIO; } + if (val >= mhi_cntrl->reg_len - (8 * mhi_cntrl->total_ev_rings)) { + dev_err(dev, "ERDB offset: 0x%x is out of range: 0x%zx\n", + val, mhi_cntrl->reg_len - (8 * mhi_cntrl->total_ev_rings)); + return -ERANGE; + } + /* Setup event db address for each ev_ring */ mhi_event = mhi_cntrl->mhi_event; for (i = 0; i < mhi_cntrl->total_ev_rings; i++, val += 8, mhi_event++) { -- cgit v1.2.3