Overview
About vulnerability
In the Linux kernel, the following vulnerability has been resolved:
Bluetooth: ISO: drop ISO_END frames received without prior ISO_START
ISO data PDUs carry a packet-boundary flag indicating START, CONT, END or SINGLE. The ISO_CONT branch of iso_recv() guards against a missing ISO_START by checking conn->rx_len before touching conn->rx_skb, but ISO_END does not.
If a peer sends an ISO_END as the first packet on a fresh ISO connection, conn->rx_skb is still NULL and conn->rx_len is zero, so skb_put(conn->rx_skb, …) dereferences NULL and oopses. For BIS, where receivers sync to a broadcaster without pairing, any broadcaster on the air can trigger this.
Mirror the ISO_CONT check at the top of ISO_END so a stray end fragment is logged and dropped instead of crashing the host.
Details
- Affected product:
- AlmaLinux 9.2 ESU , TuxCare 9.6 ESU
- Affected packages:
- kernel @ 5.14.0 (+1 more)