[PATCH 5.16 0056/1039] mei: hbm: fix client dma reply status

From: Greg Kroah-Hartman
Date: Mon Jan 24 2022 - 16:27:51 EST


From: Alexander Usyskin <alexander.usyskin@xxxxxxxxx>

commit 6b0b80ac103b2a40c72a47c301745fd1f4ef4697 upstream.

Don't blindly copy status value received from the firmware
into internal client status field,
It may be positive and ERR_PTR(ret) will translate it
into an invalid address and the caller will crash.

Put the error code into the client status on failure.

Fixes: 369aea845951 ("mei: implement client dma setup.")
Cc: <stable@xxxxxxxxxxxxxxx> # v5.11+
Reported-by: Emmanuel Grumbach <emmanuel.grumbach@xxxxxxxxx>
Tested-by: : Emmanuel Grumbach <emmanuel.grumbach@xxxxxxxxx>
Acked-by: Tomas Winkler <tomas.winkler@xxxxxxxxx>
Signed-off-by: Alexander Usyskin <alexander.usyskin@xxxxxxxxx>
Signed-off-by: Tomas Winkler <tomas.winkler@xxxxxxxxx>
Link: https://lore.kernel.org/r/20211228082047.378115-1-tomas.winkler@xxxxxxxxx
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/misc/mei/hbm.c | 20 ++++++++++++++------
1 file changed, 14 insertions(+), 6 deletions(-)

--- a/drivers/misc/mei/hbm.c
+++ b/drivers/misc/mei/hbm.c
@@ -672,10 +672,14 @@ static void mei_hbm_cl_dma_map_res(struc
if (!cl)
return;

- dev_dbg(dev->dev, "cl dma map result = %d\n", res->status);
- cl->status = res->status;
- if (!cl->status)
+ if (res->status) {
+ dev_err(dev->dev, "cl dma map failed %d\n", res->status);
+ cl->status = -EFAULT;
+ } else {
+ dev_dbg(dev->dev, "cl dma map succeeded\n");
cl->dma_mapped = 1;
+ cl->status = 0;
+ }
wake_up(&cl->wait);
}

@@ -698,10 +702,14 @@ static void mei_hbm_cl_dma_unmap_res(str
if (!cl)
return;

- dev_dbg(dev->dev, "cl dma unmap result = %d\n", res->status);
- cl->status = res->status;
- if (!cl->status)
+ if (res->status) {
+ dev_err(dev->dev, "cl dma unmap failed %d\n", res->status);
+ cl->status = -EFAULT;
+ } else {
+ dev_dbg(dev->dev, "cl dma unmap succeeded\n");
cl->dma_mapped = 0;
+ cl->status = 0;
+ }
wake_up(&cl->wait);
}