From a2cbb1a45a0c86ce77839c0875414efe1a89315e Mon Sep 17 00:00:00 2001 From: Jeffrey Hugo Date: Fri, 24 Mar 2023 10:13:04 -0600 Subject: [PATCH] bus: mhi: host: Range check CHDBOFF and ERDBOFF commit 6a0c637bfee69a74c104468544d9f2a6579626d0 upstream. 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 Signed-off-by: Greg Kroah-Hartman --- drivers/bus/mhi/host/init.c | 12 ++++++++++++ 1 file changed, 12 insertions(+) diff --git a/drivers/bus/mhi/host/init.c b/drivers/bus/mhi/host/init.c index bf672de..04fbccf 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++) { -- 2.7.4