CVE-2024-41005

/// Technical description

In the Linux kernel, the following vulnerability has been resolved:

netpoll: Fix race condition in netpoll_owner_active

KCSAN detected a race condition in netpoll:

BUG: KCSAN: data-race in net_rx_action / netpoll_send_skb

write (marked) to 0xffff8881164168b0 of 4 bytes by interrupt on cpu 10:

net_rx_action (./include/linux/netpoll.h:90 net/core/dev.c:6712 net/core/dev.c:6822)

<snip>

read to 0xffff8881164168b0 of 4 bytes by task 1 on cpu 2:

netpoll_send_skb (net/core/netpoll.c:319 net/core/netpoll.c:345 net/core/netpoll.c:393)

netpoll_send_udp (net/core/netpoll.c:?)

<snip>

value changed: 0x0000000a -> 0xffffffff

This happens because netpoll_owner_active() needs to check if the

current CPU is the owner of the lock, touching napi->poll_owner

non atomically. The ->poll_owner field contains the current CPU holding

the lock.

Use an atomic read to check if the poll owner is the current CPU.

/// Remediation

Check the references section for vendor advisories, patches, and mitigation guidance. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.

/// References