[PATCH 4.4 113/342] mei: fix fasync return value on error

From: Greg Kroah-Hartman
Date: Tue Mar 01 2016 - 20:17:15 EST


4.4-stable review patch. If anyone has any objections, please let me know.

------------------

From: Tomas Winkler <tomas.winkler@xxxxxxxxx>

commit ed6dc538e5a36a331b6256d54f435c80f6715460 upstream.

fasync should return a negative value on error
and not poll mask POLLERR.

Cc: Al Viro <viro@xxxxxxxxxxxxxxxxxx>
Reported-by: Al Viro <viro@xxxxxxxxxxxxxxxxxx>
Signed-off-by: Tomas Winkler <tomas.winkler@xxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
drivers/misc/mei/main.c | 6 ++++--
1 file changed, 4 insertions(+), 2 deletions(-)

--- a/drivers/misc/mei/main.c
+++ b/drivers/misc/mei/main.c
@@ -657,7 +657,9 @@ out:
* @file: pointer to file structure
* @band: band bitmap
*
- * Return: poll mask
+ * Return: negative on error,
+ * 0 if it did no changes,
+ * and positive a process was added or deleted
*/
static int mei_fasync(int fd, struct file *file, int band)
{
@@ -665,7 +667,7 @@ static int mei_fasync(int fd, struct fil
struct mei_cl *cl = file->private_data;

if (!mei_cl_is_connected(cl))
- return POLLERR;
+ return -ENODEV;

return fasync_helper(fd, file, band, &cl->ev_async);
}