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@eddyz87
Created March 25, 2023 11:58
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verifier/and.c converted with each insn quoted
// SPDX-License-Identifier: GPL-2.0
/* Converted from tools/testing/selftests/bpf/verifier/and.c */
#include <linux/bpf.h>
#include <bpf/bpf_helpers.h>
#include "bpf_misc.h"
#define MAX_ENTRIES 11
struct test_val {
unsigned int index;
int foo[MAX_ENTRIES];
};
struct {
__uint(type, BPF_MAP_TYPE_HASH);
__uint(max_entries, 1);
__type(key, long long);
__type(value, struct test_val);
} map_hash_48b SEC(".maps");
SEC("socket")
__description("invalid and of negative number")
__failure __msg("R0 max value is outside of the allowed memory range")
__failure_unpriv
__flag(BPF_F_ANY_ALIGNMENT)
__naked void invalid_and_of_negative_number(void)
{
asm volatile (
"r1 = 0;"
"*(u64*)(r10 - 8) = r1;"
"r2 = r10;"
"r2 += -8;"
"r1 = %[map_hash_48b] ll;"
"call %[bpf_map_lookup_elem];"
"if r0 == 0 goto l0_%=;"
"r1 = *(u8*)(r0 + 0);"
"r1 &= -4;"
"r1 <<= 2;"
"r0 += r1;"
"l0_%=:"
"r1 = %[test_val_foo];"
"*(u64*)(r0 + 0) = r1;"
"exit;"
:
: __imm(bpf_map_lookup_elem),
__imm_addr(map_hash_48b),
__imm_const(test_val_foo, offsetof(struct test_val, foo))
: __clobber_all);
}
SEC("socket")
__description("invalid range check")
__failure __msg("R0 max value is outside of the allowed memory range")
__failure_unpriv
__flag(BPF_F_ANY_ALIGNMENT)
__naked void invalid_range_check(void)
{
asm volatile (
"r1 = 0;"
"*(u64*)(r10 - 8) = r1;"
"r2 = r10;"
"r2 += -8;"
"r1 = %[map_hash_48b] ll;"
"call %[bpf_map_lookup_elem];"
"if r0 == 0 goto l0_%=;"
"r1 = *(u32*)(r0 + 0);"
"r9 = 1;"
"w1 %%= 2;"
"w1 += 1;"
"w9 &= w1;"
"w9 += 1;"
"w9 >>= 1;"
"w3 = 1;"
"w3 -= w9;"
"w3 *= 0x10000000;"
"r0 += r3;"
"*(u32*)(r0 + 0) = r3;"
"l0_%=:"
"r0 = r0;"
"exit;"
:
: __imm(bpf_map_lookup_elem),
__imm_addr(map_hash_48b)
: __clobber_all);
}
SEC("socket")
__description("check known subreg with unknown reg")
__success __failure_unpriv __msg_unpriv("R1 !read_ok")
__retval(0)
__naked void known_subreg_with_unknown_reg(void)
{
asm volatile (
"call %[bpf_get_prandom_u32];"
"r0 <<= 32;"
"r0 += 1;"
"r0 &= 0xFFFF1234;"
/* Upper bits are unknown but AND above masks out 1 zero'ing lower bits */
"if w0 < 1 goto l0_%=;"
"r1 = *(u32*)(r1 + 512);"
"l0_%=:"
"r0 = 0;"
"exit;"
:
: __imm(bpf_get_prandom_u32)
: __clobber_all);
}
char _license[] SEC("license") = "GPL";
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