| Message ID | 20210426081149.10498-1-johan@kernel.org |
|---|---|
| State | New |
| Headers | show |
| Series | net: hso: fix NULL-deref on disconnect regression | expand |
On Mon, 26 Apr 2021 10:11:49 +0200 Johan Hovold <johan@kernel.org> wrote: > Commit 8a12f8836145 ("net: hso: fix null-ptr-deref during tty device > unregistration") fixed the racy minor allocation reported by syzbot, but > introduced an unconditional NULL-pointer dereference on every disconnect > instead. > > Specifically, the serial device table must no longer be accessed after > the minor has been released by hso_serial_tty_unregister(). > > Fixes: 8a12f8836145 ("net: hso: fix null-ptr-deref during tty device unregistration") > Cc: stable@vger.kernel.org > Cc: Anirudh Rayabharam <mail@anirudhrb.com> > Reported-by: Leonardo Antoniazzi <leoanto@aruba.it> > Signed-off-by: Johan Hovold <johan@kernel.org> > --- > drivers/net/usb/hso.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/drivers/net/usb/hso.c b/drivers/net/usb/hso.c > index 9bc58e64b5b7..3ef4b2841402 100644 > --- a/drivers/net/usb/hso.c > +++ b/drivers/net/usb/hso.c > @@ -3104,7 +3104,7 @@ static void hso_free_interface(struct usb_interface *interface) > cancel_work_sync(&serial_table[i]->async_put_intf); > cancel_work_sync(&serial_table[i]->async_get_intf); > hso_serial_tty_unregister(serial); > - kref_put(&serial_table[i]->ref, hso_serial_ref_free); > + kref_put(&serial->parent->ref, hso_serial_ref_free); > } > } > > -- > 2.26.3 > hello, the patch fix the problem thanks
On Mon, Apr 26, 2021 at 11:29:11AM +0200, Leonardo Antoniazzi wrote: > On Mon, 26 Apr 2021 10:11:49 +0200 > Johan Hovold <johan@kernel.org> wrote: > > > Commit 8a12f8836145 ("net: hso: fix null-ptr-deref during tty device > > unregistration") fixed the racy minor allocation reported by syzbot, but > > introduced an unconditional NULL-pointer dereference on every disconnect > > instead. > > > > Specifically, the serial device table must no longer be accessed after > > the minor has been released by hso_serial_tty_unregister(). > > > > Fixes: 8a12f8836145 ("net: hso: fix null-ptr-deref during tty device unregistration") > > Cc: stable@vger.kernel.org > > Cc: Anirudh Rayabharam <mail@anirudhrb.com> > > Reported-by: Leonardo Antoniazzi <leoanto@aruba.it> > > Signed-off-by: Johan Hovold <johan@kernel.org> > > --- > the patch fix the problem Thanks for confirming. Next time, please keep the CC list intact when replying so that everyone sees that you've tested it. Johan
On Mon, Apr 26, 2021 at 11:35:46AM +0200, Johan Hovold wrote: > On Mon, Apr 26, 2021 at 11:29:11AM +0200, Leonardo Antoniazzi wrote: > > On Mon, 26 Apr 2021 10:11:49 +0200 > > Johan Hovold <johan@kernel.org> wrote: > > > > > Commit 8a12f8836145 ("net: hso: fix null-ptr-deref during tty device > > > unregistration") fixed the racy minor allocation reported by syzbot, but > > > introduced an unconditional NULL-pointer dereference on every disconnect > > > instead. > > > > > > Specifically, the serial device table must no longer be accessed after > > > the minor has been released by hso_serial_tty_unregister(). > > > > > > Fixes: 8a12f8836145 ("net: hso: fix null-ptr-deref during tty device unregistration") > > > Cc: stable@vger.kernel.org > > > Cc: Anirudh Rayabharam <mail@anirudhrb.com> > > > Reported-by: Leonardo Antoniazzi <leoanto@aruba.it> > > > Signed-off-by: Johan Hovold <johan@kernel.org> > > > --- > > > the patch fix the problem > > Thanks for confirming. > > Next time, please keep the CC list intact when replying so that everyone > sees that you've tested it. Wonderful. Johan, thanks for the quick fix. netdev maintainers, mind if I take this fix through my tree to Linus this week, or can you all get it to him before -rc1 through the networking tree? thanks, greg k-h
Hello: This patch was applied to netdev/net-next.git (refs/heads/master): On Mon, 26 Apr 2021 10:11:49 +0200 you wrote: > Commit 8a12f8836145 ("net: hso: fix null-ptr-deref during tty device > unregistration") fixed the racy minor allocation reported by syzbot, but > introduced an unconditional NULL-pointer dereference on every disconnect > instead. > > Specifically, the serial device table must no longer be accessed after > the minor has been released by hso_serial_tty_unregister(). > > [...] Here is the summary with links: - net: hso: fix NULL-deref on disconnect regression https://git.kernel.org/netdev/net-next/c/2ad5692db728 You are awesome, thank you! -- Deet-doot-dot, I am a bot. https://korg.docs.kernel.org/patchwork/pwbot.html
diff --git a/drivers/net/usb/hso.c b/drivers/net/usb/hso.c index 9bc58e64b5b7..3ef4b2841402 100644 --- a/drivers/net/usb/hso.c +++ b/drivers/net/usb/hso.c @@ -3104,7 +3104,7 @@ static void hso_free_interface(struct usb_interface *interface) cancel_work_sync(&serial_table[i]->async_put_intf); cancel_work_sync(&serial_table[i]->async_get_intf); hso_serial_tty_unregister(serial); - kref_put(&serial_table[i]->ref, hso_serial_ref_free); + kref_put(&serial->parent->ref, hso_serial_ref_free); } }
Commit 8a12f8836145 ("net: hso: fix null-ptr-deref during tty device unregistration") fixed the racy minor allocation reported by syzbot, but introduced an unconditional NULL-pointer dereference on every disconnect instead. Specifically, the serial device table must no longer be accessed after the minor has been released by hso_serial_tty_unregister(). Fixes: 8a12f8836145 ("net: hso: fix null-ptr-deref during tty device unregistration") Cc: stable@vger.kernel.org Cc: Anirudh Rayabharam <mail@anirudhrb.com> Reported-by: Leonardo Antoniazzi <leoanto@aruba.it> Signed-off-by: Johan Hovold <johan@kernel.org> --- drivers/net/usb/hso.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)