Commit 034d9ad2 authored by Eduard Zingerman's avatar Eduard Zingerman Committed by Alexei Starovoitov

selftests/bpf: verifier/search_pruning converted to inline assembly

Test verifier/search_pruning automatically converted to use inline assembly.
Signed-off-by: default avatarEduard Zingerman <eddyz87@gmail.com>
Link: https://lore.kernel.org/r/20230421174234.2391278-19-eddyz87@gmail.comSigned-off-by: default avatarAlexei Starovoitov <ast@kernel.org>
parent 65222842
......@@ -49,6 +49,7 @@
#include "verifier_regalloc.skel.h"
#include "verifier_ringbuf.skel.h"
#include "verifier_runtime_jit.skel.h"
#include "verifier_search_pruning.skel.h"
#include "verifier_spill_fill.skel.h"
#include "verifier_stack_ptr.skel.h"
#include "verifier_uninit.skel.h"
......@@ -139,6 +140,7 @@ void test_verifier_ref_tracking(void) { RUN(verifier_ref_tracking); }
void test_verifier_regalloc(void) { RUN(verifier_regalloc); }
void test_verifier_ringbuf(void) { RUN(verifier_ringbuf); }
void test_verifier_runtime_jit(void) { RUN(verifier_runtime_jit); }
void test_verifier_search_pruning(void) { RUN(verifier_search_pruning); }
void test_verifier_spill_fill(void) { RUN(verifier_spill_fill); }
void test_verifier_stack_ptr(void) { RUN(verifier_stack_ptr); }
void test_verifier_uninit(void) { RUN(verifier_uninit); }
......
// SPDX-License-Identifier: GPL-2.0
/* Converted from tools/testing/selftests/bpf/verifier/search_pruning.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");
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("socket")
__description("pointer/scalar confusion in state equality check (way 1)")
__success __failure_unpriv __msg_unpriv("R0 leaks addr as return value")
__retval(POINTER_VALUE)
__naked void state_equality_check_way_1(void)
{
asm volatile (" \
r1 = 0; \
*(u64*)(r10 - 8) = r1; \
r2 = r10; \
r2 += -8; \
r1 = %[map_hash_8b] ll; \
call %[bpf_map_lookup_elem]; \
if r0 == 0 goto l0_%=; \
r0 = *(u64*)(r0 + 0); \
goto l1_%=; \
l0_%=: r0 = r10; \
l1_%=: goto l2_%=; \
l2_%=: exit; \
" :
: __imm(bpf_map_lookup_elem),
__imm_addr(map_hash_8b)
: __clobber_all);
}
SEC("socket")
__description("pointer/scalar confusion in state equality check (way 2)")
__success __failure_unpriv __msg_unpriv("R0 leaks addr as return value")
__retval(POINTER_VALUE)
__naked void state_equality_check_way_2(void)
{
asm volatile (" \
r1 = 0; \
*(u64*)(r10 - 8) = r1; \
r2 = r10; \
r2 += -8; \
r1 = %[map_hash_8b] ll; \
call %[bpf_map_lookup_elem]; \
if r0 != 0 goto l0_%=; \
r0 = r10; \
goto l1_%=; \
l0_%=: r0 = *(u64*)(r0 + 0); \
l1_%=: exit; \
" :
: __imm(bpf_map_lookup_elem),
__imm_addr(map_hash_8b)
: __clobber_all);
}
SEC("lwt_in")
__description("liveness pruning and write screening")
__failure __msg("R0 !read_ok")
__naked void liveness_pruning_and_write_screening(void)
{
asm volatile (" \
/* Get an unknown value */ \
r2 = *(u32*)(r1 + 0); \
/* branch conditions teach us nothing about R2 */\
if r2 >= 0 goto l0_%=; \
r0 = 0; \
l0_%=: if r2 >= 0 goto l1_%=; \
r0 = 0; \
l1_%=: exit; \
" ::: __clobber_all);
}
SEC("socket")
__description("varlen_map_value_access pruning")
__failure __msg("R0 unbounded memory access")
__failure_unpriv __msg_unpriv("R0 leaks addr")
__flag(BPF_F_ANY_ALIGNMENT)
__naked void varlen_map_value_access_pruning(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 = *(u64*)(r0 + 0); \
w2 = %[max_entries]; \
if r2 s> r1 goto l1_%=; \
w1 = 0; \
l1_%=: w1 <<= 2; \
r0 += r1; \
goto l2_%=; \
l2_%=: r1 = %[test_val_foo]; \
*(u64*)(r0 + 0) = r1; \
l0_%=: exit; \
" :
: __imm(bpf_map_lookup_elem),
__imm_addr(map_hash_48b),
__imm_const(max_entries, MAX_ENTRIES),
__imm_const(test_val_foo, offsetof(struct test_val, foo))
: __clobber_all);
}
SEC("tracepoint")
__description("search pruning: all branches should be verified (nop operation)")
__failure __msg("R6 invalid mem access 'scalar'")
__naked void should_be_verified_nop_operation(void)
{
asm volatile (" \
r2 = r10; \
r2 += -8; \
r1 = 0; \
*(u64*)(r2 + 0) = r1; \
r1 = %[map_hash_8b] ll; \
call %[bpf_map_lookup_elem]; \
if r0 == 0 goto l0_%=; \
r3 = *(u64*)(r0 + 0); \
if r3 == 0xbeef goto l1_%=; \
r4 = 0; \
goto l2_%=; \
l1_%=: r4 = 1; \
l2_%=: *(u64*)(r10 - 16) = r4; \
call %[bpf_ktime_get_ns]; \
r5 = *(u64*)(r10 - 16); \
if r5 == 0 goto l0_%=; \
r6 = 0; \
r1 = 0xdead; \
*(u64*)(r6 + 0) = r1; \
l0_%=: exit; \
" :
: __imm(bpf_ktime_get_ns),
__imm(bpf_map_lookup_elem),
__imm_addr(map_hash_8b)
: __clobber_all);
}
SEC("socket")
__description("search pruning: all branches should be verified (invalid stack access)")
/* in privileged mode reads from uninitialized stack locations are permitted */
__success __failure_unpriv
__msg_unpriv("invalid read from stack off -16+0 size 8")
__retval(0)
__naked void be_verified_invalid_stack_access(void)
{
asm volatile (" \
r2 = r10; \
r2 += -8; \
r1 = 0; \
*(u64*)(r2 + 0) = r1; \
r1 = %[map_hash_8b] ll; \
call %[bpf_map_lookup_elem]; \
if r0 == 0 goto l0_%=; \
r3 = *(u64*)(r0 + 0); \
r4 = 0; \
if r3 == 0xbeef goto l1_%=; \
*(u64*)(r10 - 16) = r4; \
goto l2_%=; \
l1_%=: *(u64*)(r10 - 24) = r4; \
l2_%=: call %[bpf_ktime_get_ns]; \
r5 = *(u64*)(r10 - 16); \
l0_%=: exit; \
" :
: __imm(bpf_ktime_get_ns),
__imm(bpf_map_lookup_elem),
__imm_addr(map_hash_8b)
: __clobber_all);
}
SEC("tracepoint")
__description("precision tracking for u32 spill/fill")
__failure __msg("R0 min value is outside of the allowed memory range")
__naked void tracking_for_u32_spill_fill(void)
{
asm volatile (" \
r7 = r1; \
call %[bpf_get_prandom_u32]; \
w6 = 32; \
if r0 == 0 goto l0_%=; \
w6 = 4; \
l0_%=: /* Additional insns to introduce a pruning point. */\
call %[bpf_get_prandom_u32]; \
r3 = 0; \
r3 = 0; \
if r0 == 0 goto l1_%=; \
r3 = 0; \
l1_%=: /* u32 spill/fill */ \
*(u32*)(r10 - 8) = r6; \
r8 = *(u32*)(r10 - 8); \
/* out-of-bound map value access for r6=32 */ \
r1 = 0; \
*(u64*)(r10 - 16) = r1; \
r2 = r10; \
r2 += -16; \
r1 = %[map_hash_8b] ll; \
call %[bpf_map_lookup_elem]; \
if r0 == 0 goto l2_%=; \
r0 += r8; \
r1 = *(u32*)(r0 + 0); \
l2_%=: r0 = 0; \
exit; \
" :
: __imm(bpf_get_prandom_u32),
__imm(bpf_map_lookup_elem),
__imm_addr(map_hash_8b)
: __clobber_all);
}
SEC("tracepoint")
__description("precision tracking for u32 spills, u64 fill")
__failure __msg("div by zero")
__naked void for_u32_spills_u64_fill(void)
{
asm volatile (" \
call %[bpf_get_prandom_u32]; \
r6 = r0; \
w7 = 0xffffffff; \
/* Additional insns to introduce a pruning point. */\
r3 = 1; \
r3 = 1; \
r3 = 1; \
r3 = 1; \
call %[bpf_get_prandom_u32]; \
if r0 == 0 goto l0_%=; \
r3 = 1; \
l0_%=: w3 /= 0; \
/* u32 spills, u64 fill */ \
*(u32*)(r10 - 4) = r6; \
*(u32*)(r10 - 8) = r7; \
r8 = *(u64*)(r10 - 8); \
/* if r8 != X goto pc+1 r8 known in fallthrough branch */\
if r8 != 0xffffffff goto l1_%=; \
r3 = 1; \
l1_%=: /* if r8 == X goto pc+1 condition always true on first\
* traversal, so starts backtracking to mark r8 as requiring\
* precision. r7 marked as needing precision. r6 not marked\
* since it's not tracked. \
*/ \
if r8 == 0xffffffff goto l2_%=; \
/* fails if r8 correctly marked unknown after fill. */\
w3 /= 0; \
l2_%=: r0 = 0; \
exit; \
" :
: __imm(bpf_get_prandom_u32)
: __clobber_all);
}
SEC("socket")
__description("allocated_stack")
__success __msg("processed 15 insns")
__success_unpriv __msg_unpriv("") __log_level(1) __retval(0)
__naked void allocated_stack(void)
{
asm volatile (" \
r6 = r1; \
call %[bpf_get_prandom_u32]; \
r7 = r0; \
if r0 == 0 goto l0_%=; \
r0 = 0; \
*(u64*)(r10 - 8) = r6; \
r6 = *(u64*)(r10 - 8); \
*(u8*)(r10 - 9) = r7; \
r7 = *(u8*)(r10 - 9); \
l0_%=: if r0 != 0 goto l1_%=; \
l1_%=: if r0 != 0 goto l2_%=; \
l2_%=: if r0 != 0 goto l3_%=; \
l3_%=: if r0 != 0 goto l4_%=; \
l4_%=: exit; \
" :
: __imm(bpf_get_prandom_u32)
: __clobber_all);
}
/* The test performs a conditional 64-bit write to a stack location
* fp[-8], this is followed by an unconditional 8-bit write to fp[-8],
* then data is read from fp[-8]. This sequence is unsafe.
*
* The test would be mistakenly marked as safe w/o dst register parent
* preservation in verifier.c:copy_register_state() function.
*
* Note the usage of BPF_F_TEST_STATE_FREQ to force creation of the
* checkpoint state after conditional 64-bit assignment.
*/
SEC("socket")
__description("write tracking and register parent chain bug")
/* in privileged mode reads from uninitialized stack locations are permitted */
__success __failure_unpriv
__msg_unpriv("invalid read from stack off -8+1 size 8")
__retval(0) __flag(BPF_F_TEST_STATE_FREQ)
__naked void and_register_parent_chain_bug(void)
{
asm volatile (" \
/* r6 = ktime_get_ns() */ \
call %[bpf_ktime_get_ns]; \
r6 = r0; \
/* r0 = ktime_get_ns() */ \
call %[bpf_ktime_get_ns]; \
/* if r0 > r6 goto +1 */ \
if r0 > r6 goto l0_%=; \
/* *(u64 *)(r10 - 8) = 0xdeadbeef */ \
r0 = 0xdeadbeef; \
*(u64*)(r10 - 8) = r0; \
l0_%=: r1 = 42; \
*(u8*)(r10 - 8) = r1; \
r2 = *(u64*)(r10 - 8); \
/* exit(0) */ \
r0 = 0; \
exit; \
" :
: __imm(bpf_ktime_get_ns)
: __clobber_all);
}
char _license[] SEC("license") = "GPL";
{
"pointer/scalar confusion in state equality check (way 1)",
.insns = {
BPF_ST_MEM(BPF_DW, BPF_REG_10, -8, 0),
BPF_MOV64_REG(BPF_REG_2, BPF_REG_10),
BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -8),
BPF_LD_MAP_FD(BPF_REG_1, 0),
BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_map_lookup_elem),
BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 2),
BPF_LDX_MEM(BPF_DW, BPF_REG_0, BPF_REG_0, 0),
BPF_JMP_A(1),
BPF_MOV64_REG(BPF_REG_0, BPF_REG_10),
BPF_JMP_A(0),
BPF_EXIT_INSN(),
},
.fixup_map_hash_8b = { 3 },
.result = ACCEPT,
.retval = POINTER_VALUE,
.result_unpriv = REJECT,
.errstr_unpriv = "R0 leaks addr as return value"
},
{
"pointer/scalar confusion in state equality check (way 2)",
.insns = {
BPF_ST_MEM(BPF_DW, BPF_REG_10, -8, 0),
BPF_MOV64_REG(BPF_REG_2, BPF_REG_10),
BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -8),
BPF_LD_MAP_FD(BPF_REG_1, 0),
BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_map_lookup_elem),
BPF_JMP_IMM(BPF_JNE, BPF_REG_0, 0, 2),
BPF_MOV64_REG(BPF_REG_0, BPF_REG_10),
BPF_JMP_A(1),
BPF_LDX_MEM(BPF_DW, BPF_REG_0, BPF_REG_0, 0),
BPF_EXIT_INSN(),
},
.fixup_map_hash_8b = { 3 },
.result = ACCEPT,
.retval = POINTER_VALUE,
.result_unpriv = REJECT,
.errstr_unpriv = "R0 leaks addr as return value"
},
{
"liveness pruning and write screening",
.insns = {
/* Get an unknown value */
BPF_LDX_MEM(BPF_W, BPF_REG_2, BPF_REG_1, 0),
/* branch conditions teach us nothing about R2 */
BPF_JMP_IMM(BPF_JGE, BPF_REG_2, 0, 1),
BPF_MOV64_IMM(BPF_REG_0, 0),
BPF_JMP_IMM(BPF_JGE, BPF_REG_2, 0, 1),
BPF_MOV64_IMM(BPF_REG_0, 0),
BPF_EXIT_INSN(),
},
.errstr = "R0 !read_ok",
.result = REJECT,
.prog_type = BPF_PROG_TYPE_LWT_IN,
},
{
"varlen_map_value_access pruning",
.insns = {
BPF_ST_MEM(BPF_DW, BPF_REG_10, -8, 0),
BPF_MOV64_REG(BPF_REG_2, BPF_REG_10),
BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -8),
BPF_LD_MAP_FD(BPF_REG_1, 0),
BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_map_lookup_elem),
BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 8),
BPF_LDX_MEM(BPF_DW, BPF_REG_1, BPF_REG_0, 0),
BPF_MOV32_IMM(BPF_REG_2, MAX_ENTRIES),
BPF_JMP_REG(BPF_JSGT, BPF_REG_2, BPF_REG_1, 1),
BPF_MOV32_IMM(BPF_REG_1, 0),
BPF_ALU32_IMM(BPF_LSH, BPF_REG_1, 2),
BPF_ALU64_REG(BPF_ADD, BPF_REG_0, BPF_REG_1),
BPF_JMP_IMM(BPF_JA, 0, 0, 0),
BPF_ST_MEM(BPF_DW, BPF_REG_0, 0, offsetof(struct test_val, foo)),
BPF_EXIT_INSN(),
},
.fixup_map_hash_48b = { 3 },
.errstr_unpriv = "R0 leaks addr",
.errstr = "R0 unbounded memory access",
.result_unpriv = REJECT,
.result = REJECT,
.flags = F_NEEDS_EFFICIENT_UNALIGNED_ACCESS,
},
{
"search pruning: all branches should be verified (nop operation)",
.insns = {
BPF_MOV64_REG(BPF_REG_2, BPF_REG_10),
BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -8),
BPF_ST_MEM(BPF_DW, BPF_REG_2, 0, 0),
BPF_LD_MAP_FD(BPF_REG_1, 0),
BPF_EMIT_CALL(BPF_FUNC_map_lookup_elem),
BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 11),
BPF_LDX_MEM(BPF_DW, BPF_REG_3, BPF_REG_0, 0),
BPF_JMP_IMM(BPF_JEQ, BPF_REG_3, 0xbeef, 2),
BPF_MOV64_IMM(BPF_REG_4, 0),
BPF_JMP_A(1),
BPF_MOV64_IMM(BPF_REG_4, 1),
BPF_STX_MEM(BPF_DW, BPF_REG_10, BPF_REG_4, -16),
BPF_EMIT_CALL(BPF_FUNC_ktime_get_ns),
BPF_LDX_MEM(BPF_DW, BPF_REG_5, BPF_REG_10, -16),
BPF_JMP_IMM(BPF_JEQ, BPF_REG_5, 0, 2),
BPF_MOV64_IMM(BPF_REG_6, 0),
BPF_ST_MEM(BPF_DW, BPF_REG_6, 0, 0xdead),
BPF_EXIT_INSN(),
},
.fixup_map_hash_8b = { 3 },
.errstr = "R6 invalid mem access 'scalar'",
.result = REJECT,
.prog_type = BPF_PROG_TYPE_TRACEPOINT,
},
{
"search pruning: all branches should be verified (invalid stack access)",
.insns = {
BPF_MOV64_REG(BPF_REG_2, BPF_REG_10),
BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -8),
BPF_ST_MEM(BPF_DW, BPF_REG_2, 0, 0),
BPF_LD_MAP_FD(BPF_REG_1, 0),
BPF_EMIT_CALL(BPF_FUNC_map_lookup_elem),
BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 8),
BPF_LDX_MEM(BPF_DW, BPF_REG_3, BPF_REG_0, 0),
BPF_MOV64_IMM(BPF_REG_4, 0),
BPF_JMP_IMM(BPF_JEQ, BPF_REG_3, 0xbeef, 2),
BPF_STX_MEM(BPF_DW, BPF_REG_10, BPF_REG_4, -16),
BPF_JMP_A(1),
BPF_STX_MEM(BPF_DW, BPF_REG_10, BPF_REG_4, -24),
BPF_EMIT_CALL(BPF_FUNC_ktime_get_ns),
BPF_LDX_MEM(BPF_DW, BPF_REG_5, BPF_REG_10, -16),
BPF_EXIT_INSN(),
},
.fixup_map_hash_8b = { 3 },
.errstr_unpriv = "invalid read from stack off -16+0 size 8",
.result_unpriv = REJECT,
/* in privileged mode reads from uninitialized stack locations are permitted */
.result = ACCEPT,
},
{
"precision tracking for u32 spill/fill",
.insns = {
BPF_MOV64_REG(BPF_REG_7, BPF_REG_1),
BPF_EMIT_CALL(BPF_FUNC_get_prandom_u32),
BPF_MOV32_IMM(BPF_REG_6, 32),
BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 1),
BPF_MOV32_IMM(BPF_REG_6, 4),
/* Additional insns to introduce a pruning point. */
BPF_EMIT_CALL(BPF_FUNC_get_prandom_u32),
BPF_MOV64_IMM(BPF_REG_3, 0),
BPF_MOV64_IMM(BPF_REG_3, 0),
BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 1),
BPF_MOV64_IMM(BPF_REG_3, 0),
/* u32 spill/fill */
BPF_STX_MEM(BPF_W, BPF_REG_10, BPF_REG_6, -8),
BPF_LDX_MEM(BPF_W, BPF_REG_8, BPF_REG_10, -8),
/* out-of-bound map value access for r6=32 */
BPF_ST_MEM(BPF_DW, BPF_REG_10, -16, 0),
BPF_MOV64_REG(BPF_REG_2, BPF_REG_10),
BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -16),
BPF_LD_MAP_FD(BPF_REG_1, 0),
BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_map_lookup_elem),
BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 2),
BPF_ALU64_REG(BPF_ADD, BPF_REG_0, BPF_REG_8),
BPF_LDX_MEM(BPF_W, BPF_REG_1, BPF_REG_0, 0),
BPF_MOV64_IMM(BPF_REG_0, 0),
BPF_EXIT_INSN(),
},
.fixup_map_hash_8b = { 15 },
.result = REJECT,
.errstr = "R0 min value is outside of the allowed memory range",
.prog_type = BPF_PROG_TYPE_TRACEPOINT,
},
{
"precision tracking for u32 spills, u64 fill",
.insns = {
BPF_EMIT_CALL(BPF_FUNC_get_prandom_u32),
BPF_MOV64_REG(BPF_REG_6, BPF_REG_0),
BPF_MOV32_IMM(BPF_REG_7, 0xffffffff),
/* Additional insns to introduce a pruning point. */
BPF_MOV64_IMM(BPF_REG_3, 1),
BPF_MOV64_IMM(BPF_REG_3, 1),
BPF_MOV64_IMM(BPF_REG_3, 1),
BPF_MOV64_IMM(BPF_REG_3, 1),
BPF_EMIT_CALL(BPF_FUNC_get_prandom_u32),
BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 1),
BPF_MOV64_IMM(BPF_REG_3, 1),
BPF_ALU32_IMM(BPF_DIV, BPF_REG_3, 0),
/* u32 spills, u64 fill */
BPF_STX_MEM(BPF_W, BPF_REG_10, BPF_REG_6, -4),
BPF_STX_MEM(BPF_W, BPF_REG_10, BPF_REG_7, -8),
BPF_LDX_MEM(BPF_DW, BPF_REG_8, BPF_REG_10, -8),
/* if r8 != X goto pc+1 r8 known in fallthrough branch */
BPF_JMP_IMM(BPF_JNE, BPF_REG_8, 0xffffffff, 1),
BPF_MOV64_IMM(BPF_REG_3, 1),
/* if r8 == X goto pc+1 condition always true on first
* traversal, so starts backtracking to mark r8 as requiring
* precision. r7 marked as needing precision. r6 not marked
* since it's not tracked.
*/
BPF_JMP_IMM(BPF_JEQ, BPF_REG_8, 0xffffffff, 1),
/* fails if r8 correctly marked unknown after fill. */
BPF_ALU32_IMM(BPF_DIV, BPF_REG_3, 0),
BPF_MOV64_IMM(BPF_REG_0, 0),
BPF_EXIT_INSN(),
},
.result = REJECT,
.errstr = "div by zero",
.prog_type = BPF_PROG_TYPE_TRACEPOINT,
},
{
"allocated_stack",
.insns = {
BPF_ALU64_REG(BPF_MOV, BPF_REG_6, BPF_REG_1),
BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_get_prandom_u32),
BPF_ALU64_REG(BPF_MOV, BPF_REG_7, BPF_REG_0),
BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 5),
BPF_MOV64_IMM(BPF_REG_0, 0),
BPF_STX_MEM(BPF_DW, BPF_REG_10, BPF_REG_6, -8),
BPF_LDX_MEM(BPF_DW, BPF_REG_6, BPF_REG_10, -8),
BPF_STX_MEM(BPF_B, BPF_REG_10, BPF_REG_7, -9),
BPF_LDX_MEM(BPF_B, BPF_REG_7, BPF_REG_10, -9),
BPF_JMP_IMM(BPF_JNE, BPF_REG_0, 0, 0),
BPF_JMP_IMM(BPF_JNE, BPF_REG_0, 0, 0),
BPF_JMP_IMM(BPF_JNE, BPF_REG_0, 0, 0),
BPF_JMP_IMM(BPF_JNE, BPF_REG_0, 0, 0),
BPF_EXIT_INSN(),
},
.result = ACCEPT,
.result_unpriv = ACCEPT,
.insn_processed = 15,
},
/* The test performs a conditional 64-bit write to a stack location
* fp[-8], this is followed by an unconditional 8-bit write to fp[-8],
* then data is read from fp[-8]. This sequence is unsafe.
*
* The test would be mistakenly marked as safe w/o dst register parent
* preservation in verifier.c:copy_register_state() function.
*
* Note the usage of BPF_F_TEST_STATE_FREQ to force creation of the
* checkpoint state after conditional 64-bit assignment.
*/
{
"write tracking and register parent chain bug",
.insns = {
/* r6 = ktime_get_ns() */
BPF_EMIT_CALL(BPF_FUNC_ktime_get_ns),
BPF_MOV64_REG(BPF_REG_6, BPF_REG_0),
/* r0 = ktime_get_ns() */
BPF_EMIT_CALL(BPF_FUNC_ktime_get_ns),
/* if r0 > r6 goto +1 */
BPF_JMP_REG(BPF_JGT, BPF_REG_0, BPF_REG_6, 1),
/* *(u64 *)(r10 - 8) = 0xdeadbeef */
BPF_ST_MEM(BPF_DW, BPF_REG_FP, -8, 0xdeadbeef),
/* r1 = 42 */
BPF_MOV64_IMM(BPF_REG_1, 42),
/* *(u8 *)(r10 - 8) = r1 */
BPF_STX_MEM(BPF_B, BPF_REG_FP, BPF_REG_1, -8),
/* r2 = *(u64 *)(r10 - 8) */
BPF_LDX_MEM(BPF_DW, BPF_REG_2, BPF_REG_FP, -8),
/* exit(0) */
BPF_MOV64_IMM(BPF_REG_0, 0),
BPF_EXIT_INSN(),
},
.flags = BPF_F_TEST_STATE_FREQ,
.errstr_unpriv = "invalid read from stack off -8+1 size 8",
.result_unpriv = REJECT,
/* in privileged mode reads from uninitialized stack locations are permitted */
.result = ACCEPT,
},
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