On Thu, 15 Aug 2019 10:09:38 -0700, Andrii Nakryiko wrote:
> On Thu, Aug 15, 2019 at 7:24 AM Quentin Monnet wrote:
> > When showing metadata about a single program by invoking
> > "bpftool prog show PROG", the file descriptor referring to the program
> > is not closed before returning from the function. Let's close it.
> >
> > Fixes: 71bb428fe2c1 ("tools: bpf: add bpftool")
> > Signed-off-by: Quentin Monnet <[email protected]>
> > Reviewed-by: Jakub Kicinski <[email protected]>
> > ---
> > tools/bpf/bpftool/prog.c | 4 +++-
> > 1 file changed, 3 insertions(+), 1 deletion(-)
> >
> > diff --git a/tools/bpf/bpftool/prog.c b/tools/bpf/bpftool/prog.c
> > index 66f04a4846a5..43fdbbfe41bb 100644
> > --- a/tools/bpf/bpftool/prog.c
> > +++ b/tools/bpf/bpftool/prog.c
> > @@ -363,7 +363,9 @@ static int do_show(int argc, char **argv)
> > if (fd < 0)
> > return -1;
> >
> > - return show_prog(fd);
> > + err = show_prog(fd);
> > + close(fd);
> > + return err;
>
> There is a similar problem few lines above for special case of argc ==
> 2, which you didn't fix.
This is the special argc == 2 case.
> Would it be better to make show_prog(fd) close provided fd instead or
> is it used in some other context where FD should live longer (I
> haven't checked, sorry)?
I think it used to close that's how the bug crept in. Other than the bug
it's fine the way it is.
