diff options
| author | Bernd Porr <mail@berndporr.me.uk> | 2013-12-11 16:06:15 +0000 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2014-01-29 05:06:18 -0800 |
| commit | af7b2d49ef7b4171ef416b7ca2810834993afbca (patch) | |
| tree | 45ab0a55f38d594b6f273cf09d8370593ef039be | |
| parent | 1b8c5f8b4b57c574f6cf2047e80e1565b2a07f09 (diff) | |
staging: comedi: fix result of memdup_user for user chanlist
commit e56b1401056288a725d50942ef300dcbed5e519a upstream.
If the channel list is not set in userspace we get an error at
PTR_ERR(async->cmd.chanlist). However, do_become_nonbusy(dev, s) cleans
up this pointer which causes a kernel ooops. Setting the channel list in
async to NULL and checking this in do_become_nonbusy prevents the oops.
[Ian Abbott] Also do the same for the chanlist allocated in
do_cmdtest_ioctl().
Signed-off-by: Bernd Porr <mail@berndporr.me.uk>
Signed-off-by: Ian Abbott <abbotti@mev.co.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | drivers/staging/comedi/comedi_fops.c | 2 |
1 files changed, 2 insertions, 0 deletions
diff --git a/drivers/staging/comedi/comedi_fops.c b/drivers/staging/comedi/comedi_fops.c index f3d59e2a1152..341decfb81d1 100644 --- a/drivers/staging/comedi/comedi_fops.c +++ b/drivers/staging/comedi/comedi_fops.c @@ -1425,6 +1425,7 @@ static int do_cmd_ioctl(struct comedi_device *dev, async->cmd.chanlist_len * sizeof(int)); if (IS_ERR(async->cmd.chanlist)) { ret = PTR_ERR(async->cmd.chanlist); + async->cmd.chanlist = NULL; DPRINTK("memdup_user failed with code %d\n", ret); goto cleanup; } @@ -1547,6 +1548,7 @@ static int do_cmdtest_ioctl(struct comedi_device *dev, cmd.chanlist_len * sizeof(int)); if (IS_ERR(chanlist)) { ret = PTR_ERR(chanlist); + chanlist = NULL; DPRINTK("memdup_user exited with code %d", ret); goto cleanup; } |