CVE-2026-64548bpf, sockmap: reject overflowing copy + len in bpf_msg_push_data()

Official description

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.

Affected packages & fixed versions

Affected products (as reported)

References

• https://git.kernel.org/stable/c/f1644c9508d24f50dd9e8ebe8d3ba86e0996d2f5
• https://git.kernel.org/stable/c/a12b1575f9feabd91695a9e9d004862f7195fa25
• https://git.kernel.org/stable/c/ff39d0e3b4feeb65ca43c453d7c75fdf872ded0d
• https://git.kernel.org/stable/c/888706a76286c547bd035432602571e8024b5305
• https://git.kernel.org/stable/c/db77b6bb6e6edb79b10b4efcce346eec5582d588
• https://git.kernel.org/stable/c/4e40056bb5c829f0423f0a6694a0477726d2147e
• https://git.kernel.org/stable/c/bd004716ba75fed6d185795c85cdc92540ebeaab
• https://git.kernel.org/stable/c/0c0a8ed85349dae298712d79cb276acfeb794d82