On Fri, 2018-06-29 at 09:03 +0200, Hans Verkuil wrote:
> On 06/28/2018 09:25 PM, Ezequiel Garcia wrote:
> > When creating a second node via copy or assignment:
> > 
> >     node2 = node
> > 
> > The node being assigned to, i.e. node2, obtains the fd.
> > This causes a later call to node2.media_open to close()
> > the fd, thus unintendenly closing the original node fd,
> > via the call path (e.g. for media devices):
> > 
> >   node2.media_open
> >      v4l_media_open
> >         v4l_media_s_fd
> > 
> > Similar call paths apply for other device types.
> > Fix this by removing the close in xxx_s_fd.
> 
> I fixed this in a different way by overloading the assignment
> operator
> and calling dup(fd). That solves this as well.
> 

Yes, but I am now seeing another EBADF error in the compliance run.

close(3)                                = 0
openat(AT_FDCWD, "/dev/video2", O_RDWR) = 3
close(3)                                = 0
ioctl(3, VIDIOC_QUERYCAP, 0x7ffe54788794) = -1 EBADF
close(3)                                = -1 EBADF

Let me see if I can dig it.

Reply via email to