On Tue, Oct 15, 2024 at 12:40:41PM -0700, Suren Baghdasaryan wrote:
[snip]
> > -struct pid *pidfd_get_pid(unsigned int fd, unsigned int *flags)
> > +struct pid *__pidfd_get_pid(unsigned int pidfd, bool pin_pid,
> > + bool allow_proc, unsigned int *flags,
> > + struct fd *fd)
> > {
> > - struct fd f;
> > + struct file *file;
> > struct pid *pid;
> > + struct fd f = fdget(pidfd);
> >
> > - f = fdget(fd);
> > - if (!fd_file(f))
> > + file = fd_file(f);
> > + if (!file)
> > return ERR_PTR(-EBADF);
> >
> > - pid = pidfd_pid(fd_file(f));
> > - if (!IS_ERR(pid)) {
> > - get_pid(pid);
> > - *flags = fd_file(f)->f_flags;
> > + pid = pidfd_pid(file);
> > + /* If we allow opening a pidfd via /proc/<pid>, do so. */
> > + if (IS_ERR(pid) && allow_proc)
> > + pid = tgid_pidfd_to_pid(file);
> > +
> > + if (IS_ERR(pid)) {
> > + fdput(f);
> > + return pid;
> > }
> >
> > - fdput(f);
> > + if (pin_pid)
> > + get_pid(pid);
> > + else
> > + WARN_ON_ONCE(!fd); /* Nothing to keep pid/pidfd around? */
> > +
> > + if (flags)
> > + *flags = file->f_flags;
> > +
> > + /*
> > + * If the user provides an fd output then it will handle decrementing
> > + * its reference counter.
> > + */
> > + if (fd)
> > + *fd = f;
> > + else
> > + /* Otherwise we release it. */
> > + fdput(f);
> > +
> > return pid;
> > }
>
> There is an EXPORT_SYMBOL_GPL(pidfd_get_pid) right after this line. It
> should also be changed to EXPORT_SYMBOL_GPL(__pidfd_get_pid),
> otherwise __pidfd_get_pid() will not be exported. A module calling
> pidfd_get_pid() now inlined in the header file will try to call
> __pidfd_get_pid() and will have trouble resolving this symbol.
Hmm hang on not there isn't? I don't see that anywhere?
[snip]
