net/rose: Fix Use-After-Free in rose_ioctl

[ Upstream commit 810c38a369a0a0ce625b5c12169abce1dd9ccd53 ]

Because rose_ioctl() accesses sk->sk_receive_queue
without holding a sk->sk_receive_queue.lock, it can
cause a race with rose_accept().
A use-after-free for skb occurs with the following flow.
```
rose_ioctl() -> skb_peek()
rose_accept() -> skb_dequeue() -> kfree_skb()
```
Add sk->sk_receive_queue.lock to rose_ioctl() to fix this issue.

Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Signed-off-by: Hyunwoo Kim <v4bel@theori.io>
Link: https://lore.kernel.org/r/20231209100538.GA407321@v4bel-B760M-AORUS-ELITE-AX
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
This commit is contained in:
Hyunwoo Kim 2023-12-09 05:05:38 -05:00 committed by Greg Kroah-Hartman
parent 531fd46f92
commit 63caa51833
1 changed files with 3 additions and 1 deletions

View File

@ -1315,9 +1315,11 @@ static int rose_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
case TIOCINQ: { case TIOCINQ: {
struct sk_buff *skb; struct sk_buff *skb;
long amount = 0L; long amount = 0L;
/* These two are safe on a single CPU system as only user tasks fiddle here */
spin_lock_irq(&sk->sk_receive_queue.lock);
if ((skb = skb_peek(&sk->sk_receive_queue)) != NULL) if ((skb = skb_peek(&sk->sk_receive_queue)) != NULL)
amount = skb->len; amount = skb->len;
spin_unlock_irq(&sk->sk_receive_queue.lock);
return put_user(amount, (unsigned int __user *) argp); return put_user(amount, (unsigned int __user *) argp);
} }