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

staging: comedi: 8255: fix I/O region leak on failure

Browse Source 
The Comedi "8255" driver does not clean up properly on failure.  It can
leave requested I/O port regions unreleased.  Specifically, the Comedi
"attach" handler (`dev_8255_attach()`) requests a specified I/O port
region before calling `subdev_8255_init()` to set up the subdevice.  If
that fails, the "attach" handler returns an error and the Comedi core
will call the "detach" handler (`dev_8255_detach()`) to clean up.  The
"detach" handler is responsible for releasing the I/O port regions
successfully requested by the "attach" handler.  Unfortunately, it is
unable to obtain the base address of the region if the call to
`subdev_8255_init()` failed.

Fix the I/O region leak by releasing the region in the "attach" handler
directly if the call to `subdev_8255_init()` fails.

Signed-off-by: Ian Abbott <abbotti@mev.co.uk>
Reviewed-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Ian Abbott 2015-05-22 16:21:35 +01:00 committed by Greg Kroah-Hartman
parent 613462e1e4
commit 7e0b1b60cb
1 changed files with 8 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

9
drivers/staging/comedi/drivers/8255.c
View File

@ -306,8 +306,15 @@ static int dev_8255_attach(struct comedi_device *dev,
s->type = COMEDI_SUBD_UNUSED;
} else {
ret = subdev_8255_init(dev, s, NULL, iobase);
if (ret)
if (ret) {
/*
* Release the I/O port region here, as the
* "detach" handler cannot find it.
*/
release_region(iobase, I8255_SIZE);
s->type = COMEDI_SUBD_UNUSED;
return ret;
}
}
}