On 1/26/23 3:29 AM, Dan Carpenter wrote:
The > comparison should be changed to >= to prevent an out of bounds
access into the mhi_cntrl->mhi_chan[] array. The mhi_cntrl->mhi_chan[]
array is allocated in mhi_ep_chan_init() and has mhi_cntrl->max_chan
elements.
You're right. I scanned through that file and there
are other spots that don't check that the channel ID
is in range, though I think this is the one where it's
reading it from an external source. I.e., the other
places are aleady known to be correct. (Maybe Mani
can comment.)
Reviewed-by: Alex Elder <elder@xxxxxxxxxx>
Fixes: 2527ad44ddb2 ("bus: mhi: ep: Check if the channel is supported by the controller")
Signed-off-by: Dan Carpenter <error27@xxxxxxxxx>
---
drivers/bus/mhi/ep/main.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/bus/mhi/ep/main.c b/drivers/bus/mhi/ep/main.c
index bcaaba97ef63..be2d56e7f392 100644
--- a/drivers/bus/mhi/ep/main.c
+++ b/drivers/bus/mhi/ep/main.c
@@ -125,7 +125,7 @@ static int mhi_ep_process_cmd_ring(struct mhi_ep_ring *ring, struct mhi_ring_ele
ch_id = MHI_TRE_GET_CMD_CHID(el);
/* Check if the channel is supported by the controller */
- if ((ch_id > mhi_cntrl->max_chan) || !mhi_cntrl->mhi_chan[ch_id].name) {
+ if ((ch_id >= mhi_cntrl->max_chan) || !mhi_cntrl->mhi_chan[ch_id].name) {
dev_err(dev, "Channel (%u) not supported!\n", ch_id);
return -ENODEV;
}