From: Jeffrey Hugo <quic_jhugo@xxxxxxxxxxx>
[ Upstream commit 6a0c637bfee69a74c104468544d9f2a6579626d0 ]
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@xxxxxxxxxxxxxxx
Signed-off-by: Jeffrey Hugo <quic_jhugo@xxxxxxxxxxx>
Reviewed-by: Pranjal Ramajor Asha Kanojiya <quic_pkanojiy@xxxxxxxxxxx>
Reviewed-by: Manivannan Sadhasivam <mani@xxxxxxxxxx>
Link: https://lore.kernel.org/r/1679674384-27209-1-git-send-email-quic_jhugo@xxxxxxxxxxx
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
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 0d0386f67ffe2..2cc48f96afdbc 100644
--- a/drivers/bus/mhi/host/init.c
+++ b/drivers/bus/mhi/host/init.c
@@ -498,6 +498,12 @@ 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_write_reg(mhi_cntrl, mhi_cntrl->wake_db, 4, 0);
@@ -517,6 +523,12 @@ 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++) {
--
2.40.1
