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{
"BPF_ATOMIC bounds propagation, mem->reg",
.insns = {
/* a = 0; */
/*
* Note this is implemented with two separate instructions,
* where you might think one would suffice:
*
* BPF_ST_MEM(BPF_DW, BPF_REG_10, -8, 0),
*
* This is because BPF_ST_MEM doesn't seem to set the stack slot
* type to 0 when storing an immediate.
*/
BPF_MOV64_IMM(BPF_REG_0, 0),
BPF_STX_MEM(BPF_DW, BPF_REG_10, BPF_REG_0, -8),
/* b = atomic_fetch_add(&a, 1); */
BPF_MOV64_IMM(BPF_REG_1, 1),
BPF_ATOMIC_OP(BPF_DW, BPF_ADD | BPF_FETCH, BPF_REG_10, BPF_REG_1, -8),
/* Verifier should be able to tell that this infinite loop isn't reachable. */
/* if (b) while (true) continue; */
BPF_JMP_IMM(BPF_JNE, BPF_REG_1, 0, -1),
BPF_EXIT_INSN(),
},
.result = ACCEPT,
.result_unpriv = REJECT,
.errstr_unpriv = "back-edge",
},
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