CVE-2026-64548

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

bpf, sockmap: reject overflowing copy + len in bpf_msg_push_data()

When the scatterlist ring is full or nearly full, bpf_msg_push_data()

enters a copy fallback path and computes copy + len for the page

allocation size. Since len comes from BPF with arg3_type = ARG_ANYTHING

and both are u32, a crafted len can wrap the sum to a small value,

causing an undersized allocation followed by an out-of-bounds memcpy.

BUG: unable to handle page fault for address: ffffed104089a402

Oops: Oops: 0000 [#1] SMP KASAN NOPTI

Call Trace:

__asan_memcpy (mm/kasan/shadow.c:105)

bpf_msg_push_data (net/core/filter.c:2852 net/core/filter.c:2788)

bpf_prog_9ed8b5711920a7d7+0x2e/0x36

sk_psock_msg_verdict (net/core/skmsg.c:934)

tcp_bpf_sendmsg (net/ipv4/tcp_bpf.c:421 net/ipv4/tcp_bpf.c:584)

__sys_sendto (net/socket.c:2206)

do_syscall_64 (arch/x86/entry/syscall_64.c:94)

entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:130)

Add an overflow check before the allocation.