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authorTomas Winkler <[email protected]>2021-03-18 07:59:59 +0200
committerGreg Kroah-Hartman <[email protected]>2021-03-23 15:15:15 +0100
commitce068bc7da473e39b64d130101e178406023df0c (patch)
tree4d37a3caccb9ba2545535f0431e6638d2d685a70
parent903079a54cac47ab115fa5abbde6860cf94e258f (diff)
mei: allow map and unmap of client dma buffer only for disconnected client
Allow map and unmap of the client dma buffer only when the client is not connected. The functions return -EPROTO if the client is already connected. This is to fix the race when traffic may start or stop when buffer is not available. Cc: <[email protected]> #v5.11+ Signed-off-by: Tomas Winkler <[email protected]> Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Greg Kroah-Hartman <[email protected]>
-rw-r--r--drivers/misc/mei/client.c17
1 files changed, 7 insertions, 10 deletions
diff --git a/drivers/misc/mei/client.c b/drivers/misc/mei/client.c
index 4378a9b25848..2cc370adb238 100644
--- a/drivers/misc/mei/client.c
+++ b/drivers/misc/mei/client.c
@@ -2286,8 +2286,8 @@ int mei_cl_dma_alloc_and_map(struct mei_cl *cl, const struct file *fp,
if (buffer_id == 0)
return -EINVAL;
- if (!mei_cl_is_connected(cl))
- return -ENODEV;
+ if (mei_cl_is_connected(cl))
+ return -EPROTO;
if (cl->dma_mapped)
return -EPROTO;
@@ -2327,9 +2327,7 @@ int mei_cl_dma_alloc_and_map(struct mei_cl *cl, const struct file *fp,
mutex_unlock(&dev->device_lock);
wait_event_timeout(cl->wait,
- cl->dma_mapped ||
- cl->status ||
- !mei_cl_is_connected(cl),
+ cl->dma_mapped || cl->status,
mei_secs_to_jiffies(MEI_CL_CONNECT_TIMEOUT));
mutex_lock(&dev->device_lock);
@@ -2376,8 +2374,9 @@ int mei_cl_dma_unmap(struct mei_cl *cl, const struct file *fp)
return -EOPNOTSUPP;
}
- if (!mei_cl_is_connected(cl))
- return -ENODEV;
+ /* do not allow unmap for connected client */
+ if (mei_cl_is_connected(cl))
+ return -EPROTO;
if (!cl->dma_mapped)
return -EPROTO;
@@ -2405,9 +2404,7 @@ int mei_cl_dma_unmap(struct mei_cl *cl, const struct file *fp)
mutex_unlock(&dev->device_lock);
wait_event_timeout(cl->wait,
- !cl->dma_mapped ||
- cl->status ||
- !mei_cl_is_connected(cl),
+ !cl->dma_mapped || cl->status,
mei_secs_to_jiffies(MEI_CL_CONNECT_TIMEOUT));
mutex_lock(&dev->device_lock);