CVE-2021-47520 Information

Description

In the Linux kernel the following vulnerability has been resolved:

can: pch_can: pch_can_rx_normal: fix use after free

After calling netif_receive_skb(skb) dereferencing skb is unsafe. Especially the can_frame cf which aliases skb memory is dereferenced just after the call netif_receive_skb(skb).

Reordering the lines solves the issue.

Reference

https://git.kernel.org/stable/c/bafe343a885c70dddf358379cf0b2a1c07355d8d https://git.kernel.org/stable/c/3a3c46e2eff0577454860a203be1a8295f4acb76 https://git.kernel.org/stable/c/affbad02bf80380a7403885b9fe4a1587d1bb4f3 https://git.kernel.org/stable/c/3e193ef4e0a3f5bf92ede83ef214cb09d01b00aa https://git.kernel.org/stable/c/abb4eff3dcd2e583060082a18a8dbf31f02689d4 https://git.kernel.org/stable/c/703dde112021c93d6e89443c070e7dbd4dea612e https://git.kernel.org/stable/c/6c73fc931658d8cbc8a1714b326cb31eb71d16a7 https://git.kernel.org/stable/c/94cddf1e9227a171b27292509d59691819c458db