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 quic_jhugo@quicinc.com Reviewed-by: Pranjal Ramajor Asha Kanojiya quic_pkanojiy@quicinc.com Reviewed-by: Manivannan Sadhasivam mani@kernel.org Link: https://lore.kernel.org/r/1679674384-27209-1-git-send-email-quic_jhugo@quici... Signed-off-by: Manivannan Sadhasivam manivannan.sadhasivam@linaro.org --- drivers/bus/mhi/core/init.c | 12 ++++++++++++ 1 file changed, 12 insertions(+)
diff --git a/drivers/bus/mhi/core/init.c b/drivers/bus/mhi/core/init.c index d8787aa..829d4fc 100644 --- a/drivers/bus/mhi/core/init.c +++ b/drivers/bus/mhi/core/init.c @@ -517,6 +517,12 @@ 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; @@ -534,6 +540,12 @@ 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++) {