CVE-2025-38465

In the Linux kernel, the following vulnerability has been resolved: netlink: Fix wraparounds of sk->sk_rmem_alloc. Netlink has this pattern in some places if (atomic_read(&sk->sk_rmem_alloc) > sk->sk_rcvbuf) atomic_add(skb->truesize, &sk->sk_rmem_alloc); , which has the same problem fixed by commit 5a465a0da13e ("udp: Fix multiple wraparounds of sk->sk_rmem_alloc."). For example, if we set INT_MAX to SO_RCVBUFFORCE, the condition is always false as the two operands are of int. Then, a single socket can eat as many skb as possible until OOM happens, and we can see multiple wraparounds of sk->sk_rmem_alloc. Let's fix it by using atomic_add_return() and comparing the two variables as unsigned int. Before: [root@fedora ~]# ss -f netlink Recv-Q Send-Q Local Address:Port Peer Address:Port -1668710080 0 rtnl:nl_wraparound/293 * After: [root@fedora ~]# ss -f netlink Recv-Q Send-Q Local Address:Port Peer Address:Port 2147483072 0 rtnl:nl_wraparound/290 * ^ `--- INT_MAX - 576

• linux linux kernel (>= 2.6.13 < 5.4.296) • linux linux kernel (>= 5.5 < 5.10.240) • linux linux kernel (>= 5.11 < 5.15.189) • linux linux kernel (>= 5.16 < 6.1.146) • linux linux kernel (>= 6.2 < 6.6.99) • linux linux kernel (>= 6.7 < 6.12.39) • linux linux kernel (>= 6.13 < 6.15.7) • linux linux kernel 2.6.12 • linux linux kernel 6.16 • debian debian linux 11.0