1 // SPDX-License-Identifier: GPL-2.0 2 3 #include <vmlinux.h> 4 #include <bpf/bpf_helpers.h> 5 #include "bpf_misc.h" 6 7 SEC("iter/bpf_map_elem") 8 __description("PTR_TO_BUF: reject negative const offset") 9 __failure 10 __msg("invalid negative rdwr buffer offset") 11 __naked void ptr_to_buf_reject_negative_const_offset(void) 12 { 13 asm volatile ("r0 = 0; \ 14 r2 = *(u64 *)(r1 + %[value_off]); \ 15 if r2 == 0 goto l0_%=; \ 16 r2 += -8; \ 17 r0 = *(u64 *)(r2 + 0); \ 18 l0_%=: \ 19 exit; \ 20 " 21 : 22 : __imm_const(value_off, 23 offsetof(struct bpf_iter__bpf_map_elem, value)) 24 : __clobber_all); 25 } 26 27 char _license[] SEC("license") = "GPL"; 28