leandrof/linux
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

mei: allow map and unmap of client dma buffer only for disconnected client

Browse Source 
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: <stable@vger.kernel.org> #v5.11+
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Link: https://lore.kernel.org/r/20210318055959.305627-1-tomas.winkler@intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Tomas Winkler 2021-03-18 07:59:59 +02:00 committed by Greg Kroah-Hartman
parent 903079a54c
commit ce068bc7da
1 changed files with 7 additions and 10 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

17
drivers/misc/mei/client.c
View File

@ -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);