diff options
Diffstat (limited to 'tools/testing/selftests/bpf/progs/verifier_search_pruning.c')
| -rw-r--r-- | tools/testing/selftests/bpf/progs/verifier_search_pruning.c | 339 |
1 files changed, 339 insertions, 0 deletions
diff --git a/tools/testing/selftests/bpf/progs/verifier_search_pruning.c b/tools/testing/selftests/bpf/progs/verifier_search_pruning.c new file mode 100644 index 000000000000..5a14498d352f --- /dev/null +++ b/tools/testing/selftests/bpf/progs/verifier_search_pruning.c @@ -0,0 +1,339 @@ +// 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"; |