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// SPDX-License-Identifier: GPL-2.0
/* Converted from tools/testing/selftests/bpf/verifier/raw_tp_writable.c */
#include <linux/bpf.h>
#include <bpf/bpf_helpers.h>
#include "bpf_misc.h"
struct {
__uint(type, BPF_MAP_TYPE_HASH);
__uint(max_entries, 1);
__type(key, long long);
__type(value, long long);
} map_hash_8b SEC(".maps");
SEC("raw_tracepoint.w")
__description("raw_tracepoint_writable: reject variable offset")
__failure
__msg("R6 invalid variable buffer offset: off=0, var_off=(0x0; 0xffffffff)")
__flag(BPF_F_ANY_ALIGNMENT)
__naked void tracepoint_writable_reject_variable_offset(void)
{
asm volatile (" \
/* r6 is our tp buffer */ \
r6 = *(u64*)(r1 + 0); \
r1 = %[map_hash_8b] ll; \
/* move the key (== 0) to r10-8 */ \
w0 = 0; \
r2 = r10; \
r2 += -8; \
*(u64*)(r2 + 0) = r0; \
/* lookup in the map */ \
call %[bpf_map_lookup_elem]; \
/* exit clean if null */ \
if r0 != 0 goto l0_%=; \
exit; \
l0_%=: /* shift the buffer pointer to a variable location */\
r0 = *(u32*)(r0 + 0); \
r6 += r0; \
/* clobber whatever's there */ \
r7 = 4242; \
*(u64*)(r6 + 0) = r7; \
r0 = 0; \
exit; \
" :
: __imm(bpf_map_lookup_elem),
__imm_addr(map_hash_8b)
: __clobber_all);
}
char _license[] SEC("license") = "GPL";
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