diff options
| author | Ian Abbott | 2015-11-18 18:55:09 +0100 |
|---|---|---|
| committer | Greg Kroah-Hartman | 2015-12-22 00:58:54 +0100 |
| commit | 40d0e80e08012ac99b187cbaaeb8aab92b71714d (patch) | |
| tree | 779e97ea7e0188c9418f959f3dc4780b5c1f9ddd /drivers/staging/comedi/comedi_fops.c | |
| parent | staging: comedi: allow buffer wraparound in comedi_write() (diff) | |
| download | kernel-qcow2-linux-40d0e80e08012ac99b187cbaaeb8aab92b71714d.tar.gz kernel-qcow2-linux-40d0e80e08012ac99b187cbaaeb8aab92b71714d.tar.xz kernel-qcow2-linux-40d0e80e08012ac99b187cbaaeb8aab92b71714d.zip | |
staging: comedi: return error on "write" if no command set up
The "write" file operation handler, `comedi_write()` returns an error
for pretty much any condition that prevents a "write" going ahead. One
of the conditions that prevents a "write" going ahead is that no
asynchronous command has been set up, but that currently results in a
return value of 0 (unless COMEDI instructions are being processed or an
asynchronous command has been set up by a different file object).
Change it to return `-EINVAL` in this case.
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>
Diffstat (limited to 'drivers/staging/comedi/comedi_fops.c')
| -rw-r--r-- | drivers/staging/comedi/comedi_fops.c | 11 |
1 files changed, 8 insertions, 3 deletions
diff --git a/drivers/staging/comedi/comedi_fops.c b/drivers/staging/comedi/comedi_fops.c index 4dd42890c641..2a2b5a06ed0e 100644 --- a/drivers/staging/comedi/comedi_fops.c +++ b/drivers/staging/comedi/comedi_fops.c @@ -2331,9 +2331,12 @@ static ssize_t comedi_write(struct file *file, const char __user *buf, } async = s->async; - - if (!s->busy || !nbytes) + if (!nbytes) + goto out; + if (!s->busy) { + retval = -EINVAL; goto out; + } if (s->busy != file) { retval = -EACCES; goto out; @@ -2373,8 +2376,10 @@ static ssize_t comedi_write(struct file *file, const char __user *buf, retval = -ERESTARTSYS; break; } - if (!s->busy) + if (!s->busy) { + retval = -EINVAL; break; + } if (s->busy != file) { retval = -EACCES; break; |