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1// SPDX-License-Identifier: GPL-2.02 3#include <linux/bpf.h>4#include <bpf/bpf_helpers.h>5#include "bpf_misc.h"6 7SEC("socket")8__description("check w reg equal if r reg upper32 bits 0")9__success10__naked void subreg_equality_1(void)11{12 asm volatile (" \13 call %[bpf_ktime_get_ns]; \14 *(u64 *)(r10 - 8) = r0; \15 r2 = *(u32 *)(r10 - 8); \16 /* At this point upper 4-bytes of r2 are 0, \17 * thus insn w3 = w2 should propagate reg id, \18 * and w2 < 9 comparison would also propagate \19 * the range for r3. \20 */ \21 w3 = w2; \22 if w2 < 9 goto l0_%=; \23 exit; \24l0_%=: if r3 < 9 goto l1_%=; \25 /* r1 read is illegal at this point */ \26 r0 -= r1; \27l1_%=: exit; \28" :29 : __imm(bpf_ktime_get_ns)30 : __clobber_all);31}32 33SEC("socket")34__description("check w reg not equal if r reg upper32 bits not 0")35__failure __msg("R1 !read_ok")36__naked void subreg_equality_2(void)37{38 asm volatile (" \39 call %[bpf_ktime_get_ns]; \40 r2 = r0; \41 /* Upper 4-bytes of r2 may not be 0, thus insn \42 * w3 = w2 should not propagate reg id, and \43 * w2 < 9 comparison should not propagate \44 * the range for r3 either. \45 */ \46 w3 = w2; \47 if w2 < 9 goto l0_%=; \48 exit; \49l0_%=: if r3 < 9 goto l1_%=; \50 /* r1 read is illegal at this point */ \51 r0 -= r1; \52l1_%=: exit; \53" :54 : __imm(bpf_ktime_get_ns)55 : __clobber_all);56}57 58char _license[] SEC("license") = "GPL";59