[IRDA]: Fix rfcomm use-after-free
Adrian Bunk wrote:
> Commit 8de0a15483b357d0f0b821330ec84d1660cadc4e added the following
> use-after-free in net/bluetooth/rfcomm/tty.c:
>
> <-- snip -->
>
> ...
> static int rfcomm_dev_add(struct rfcomm_dev_req *req, struct rfcomm_dlc *dlc)
> {
> ...
> if (IS_ERR(dev->tty_dev)) {
> list_del(&dev->list);
> kfree(dev);
> return PTR_ERR(dev->tty_dev);
> }
> ...
>
> <-- snip -->
>
> Spotted by the Coverity checker.
really good catch. I fully overlooked that one. The attached patch
should fix it.
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/bluetooth/rfcomm/tty.c b/net/bluetooth/rfcomm/tty.c
index 23ba61a..22a8320 100644
--- a/net/bluetooth/rfcomm/tty.c
+++ b/net/bluetooth/rfcomm/tty.c
@@ -267,7 +267,7 @@
out:
write_unlock_bh(&rfcomm_dev_lock);
- if (err) {
+ if (err < 0) {
kfree(dev);
return err;
}
@@ -275,9 +275,10 @@
dev->tty_dev = tty_register_device(rfcomm_tty_driver, dev->id, NULL);
if (IS_ERR(dev->tty_dev)) {
+ err = PTR_ERR(dev->tty_dev);
list_del(&dev->list);
kfree(dev);
- return PTR_ERR(dev->tty_dev);
+ return err;
}
return dev->id;