[34-longterm 212/247] USB: cdc-acm: fix potential null-pointer dereference

Paul Gortmaker
2011-06-23T17:50:57Z

From: Johan Hovold <jhovold@gmail.com>

-------------------
This is a commit scheduled for the next v2.6.34 longterm release.
If you see a problem with using this for longterm, please comment.
-------------------

commit 15e5bee33ffc11d0e5c6f819a65e7881c5c407be upstream.

Must check return value of tty_port_tty_get.

Signed-off-by: Johan Hovold <jhovold@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
---
drivers/usb/class/cdc-acm.c | 2 ++
1 files changed, 2 insertions(+), 0 deletions(-)

diff --git a/drivers/usb/class/cdc-acm.c b/drivers/usb/class/cdc-acm.c
index 073a9ef..af5ed89 100644
--- a/drivers/usb/class/cdc-acm.c
+++ b/drivers/usb/class/cdc-acm.c
@@ -534,6 +534,8 @@ static void acm_softint(struct work_struct *work)
if (!ACM_READY(acm))
return;
tty = tty_port_tty_get(&acm->port);
+ if (!tty)
+ return;
tty_wakeup(tty);
tty_kref_put(tty);
}
--
1.7.4.4