CVE-2026-74256
CVE-2026-74256CVE-2026-74256
Description
In the Linux kernel, the following vulnerability has been resolved:
bpf, sockmap: fix integer overflow in bpf_msg_pop_data() bounds check
start and len are u32, so
u64 last = start + len;
evaluates start + len in 32-bit and wraps before storing it in last.
The bounds check
if (start >= offset + l || last > msg->sg.size)
return -EINVAL;
can then be passed with an out-of-range start/len, after which the pop
loop runs off the end of the scatterlist and sk_msg_shift_left() calls
put_page() on the empty msg->sg.end slot:
Oops: general protection fault, probably for non-canonical address
0xdffffc0000000001: 0000 [#1] SMP KASAN PTI
KASAN: null-ptr-deref in range [0x0000000000000008-0x000000000000000f]
RIP: 0010:sk_msg_shift_left net/core/filter.c:2957 [inline]
RIP: 0010:____bpf_msg_pop_data net/core/filter.c:3103 [inline]
RIP: 0010:bpf_msg_pop_data+0x753/0x1a10 net/core/filter.c:2984
Call Trace:
<TASK>
bpf_prog_4cc92c278f4d5d56+0x1b1/0x1e8
bpf_prog_run_pin_on
Scoring
| Last modified | 2026-08-15 |