From 8aefdd25a3f794c7099ac77056d8fa74c28e7bcc Mon Sep 17 00:00:00 2001 From: Matthew Dillon Date: Tue, 29 Jan 2013 11:19:22 -0800 Subject: [PATCH] kernel - Attempt to fix NULL pointer dereference during console switch * Attempt to fix NULL pointer dereference during console switch. Bug 2481. Reported-by: marino --- sys/dev/misc/syscons/syscons.c | 8 +++++++- 1 files changed, 7 insertions(+), 1 deletions(-) diff --git a/sys/dev/misc/syscons/syscons.c b/sys/dev/misc/syscons/syscons.c index c6a6cb5..afc9bbc 100644 --- a/sys/dev/misc/syscons/syscons.c +++ b/sys/dev/misc/syscons/syscons.c @@ -1093,8 +1093,14 @@ scioctl(struct dev_ioctl_args *ap) lwkt_reltoken(&tty_token); return error; } + + /* + * scp might be NULL, we aren't sure why. Check for NULL. + * + * http://bugs.dragonflybsd.org/issues/2481 + */ scp = SC_STAT(SC_DEV(sc, i)); - if (scp == scp->sc->cur_scp) { + if (scp == NULL || scp == scp->sc->cur_scp) { lwkt_reltoken(&tty_token); return 0; } -- 1.7.7.2