]> git.kernelconcepts.de Git - karo-tx-linux.git/blobdiff - samples/bpf/test_verifier.c
Merge remote-tracking branch 'ipsec/master'
[karo-tx-linux.git] / samples / bpf / test_verifier.c
index ee0f110c9c543b54fd8593607d161598fb29e472..563c507c0a09f3868827ce6ce1e0e88669803016 100644 (file)
 #include <string.h>
 #include <linux/filter.h>
 #include <stddef.h>
+#include <stdbool.h>
+#include <sys/resource.h>
 #include "libbpf.h"
 
 #define MAX_INSNS 512
 #define ARRAY_SIZE(x) (sizeof(x) / sizeof(*(x)))
 
+#define MAX_FIXUPS 8
+
 struct bpf_test {
        const char *descr;
        struct bpf_insn insns[MAX_INSNS];
-       int fixup[32];
+       int fixup[MAX_FIXUPS];
+       int prog_array_fixup[MAX_FIXUPS];
        const char *errstr;
+       const char *errstr_unpriv;
        enum {
+               UNDEF,
                ACCEPT,
                REJECT
-       } result;
+       } result, result_unpriv;
        enum bpf_prog_type prog_type;
 };
 
@@ -96,6 +103,7 @@ static struct bpf_test tests[] = {
                        BPF_EXIT_INSN(),
                },
                .errstr = "invalid BPF_LD_IMM insn",
+               .errstr_unpriv = "R1 pointer comparison",
                .result = REJECT,
        },
        {
@@ -109,6 +117,7 @@ static struct bpf_test tests[] = {
                        BPF_EXIT_INSN(),
                },
                .errstr = "invalid BPF_LD_IMM insn",
+               .errstr_unpriv = "R1 pointer comparison",
                .result = REJECT,
        },
        {
@@ -219,6 +228,7 @@ static struct bpf_test tests[] = {
                        BPF_EXIT_INSN(),
                },
                .errstr = "R0 !read_ok",
+               .errstr_unpriv = "R1 pointer comparison",
                .result = REJECT,
        },
        {
@@ -294,7 +304,9 @@ static struct bpf_test tests[] = {
                        BPF_MOV64_REG(BPF_REG_0, BPF_REG_2),
                        BPF_EXIT_INSN(),
                },
+               .errstr_unpriv = "R0 leaks addr",
                .result = ACCEPT,
+               .result_unpriv = REJECT,
        },
        {
                "check corrupted spill/fill",
@@ -310,6 +322,7 @@ static struct bpf_test tests[] = {
 
                        BPF_EXIT_INSN(),
                },
+               .errstr_unpriv = "attempt to corrupt spilled",
                .errstr = "corrupted spill",
                .result = REJECT,
        },
@@ -473,6 +486,7 @@ static struct bpf_test tests[] = {
                },
                .fixup = {3},
                .errstr = "R0 invalid mem access",
+               .errstr_unpriv = "R0 leaks addr",
                .result = REJECT,
        },
        {
@@ -495,6 +509,8 @@ static struct bpf_test tests[] = {
                        BPF_MOV64_IMM(BPF_REG_0, 0),
                        BPF_EXIT_INSN(),
                },
+               .errstr_unpriv = "R1 pointer comparison",
+               .result_unpriv = REJECT,
                .result = ACCEPT,
        },
        {
@@ -521,6 +537,8 @@ static struct bpf_test tests[] = {
                        BPF_MOV64_IMM(BPF_REG_0, 0),
                        BPF_EXIT_INSN(),
                },
+               .errstr_unpriv = "R1 pointer comparison",
+               .result_unpriv = REJECT,
                .result = ACCEPT,
        },
        {
@@ -555,6 +573,8 @@ static struct bpf_test tests[] = {
                        BPF_EXIT_INSN(),
                },
                .fixup = {24},
+               .errstr_unpriv = "R1 pointer comparison",
+               .result_unpriv = REJECT,
                .result = ACCEPT,
        },
        {
@@ -603,6 +623,8 @@ static struct bpf_test tests[] = {
                        BPF_MOV64_IMM(BPF_REG_0, 0),
                        BPF_EXIT_INSN(),
                },
+               .errstr_unpriv = "R1 pointer comparison",
+               .result_unpriv = REJECT,
                .result = ACCEPT,
        },
        {
@@ -642,6 +664,8 @@ static struct bpf_test tests[] = {
                        BPF_MOV64_IMM(BPF_REG_0, 0),
                        BPF_EXIT_INSN(),
                },
+               .errstr_unpriv = "R1 pointer comparison",
+               .result_unpriv = REJECT,
                .result = ACCEPT,
        },
        {
@@ -699,6 +723,7 @@ static struct bpf_test tests[] = {
                },
                .fixup = {4},
                .errstr = "different pointers",
+               .errstr_unpriv = "R1 pointer comparison",
                .result = REJECT,
        },
        {
@@ -720,6 +745,7 @@ static struct bpf_test tests[] = {
                },
                .fixup = {6},
                .errstr = "different pointers",
+               .errstr_unpriv = "R1 pointer comparison",
                .result = REJECT,
        },
        {
@@ -742,6 +768,7 @@ static struct bpf_test tests[] = {
                },
                .fixup = {7},
                .errstr = "different pointers",
+               .errstr_unpriv = "R1 pointer comparison",
                .result = REJECT,
        },
        {
@@ -752,6 +779,7 @@ static struct bpf_test tests[] = {
                        BPF_EXIT_INSN(),
                },
                .errstr = "invalid bpf_context access",
+               .errstr_unpriv = "R1 leaks addr",
                .result = REJECT,
        },
        {
@@ -762,6 +790,7 @@ static struct bpf_test tests[] = {
                        BPF_EXIT_INSN(),
                },
                .errstr = "invalid bpf_context access",
+               .errstr_unpriv = "R1 leaks addr",
                .result = REJECT,
        },
        {
@@ -772,16 +801,18 @@ static struct bpf_test tests[] = {
                        BPF_EXIT_INSN(),
                },
                .errstr = "invalid bpf_context access",
+               .errstr_unpriv = "R1 leaks addr",
                .result = REJECT,
        },
        {
                "check out of range skb->cb access",
                .insns = {
                        BPF_LDX_MEM(BPF_W, BPF_REG_0, BPF_REG_1,
-                                   offsetof(struct __sk_buff, cb[60])),
+                                   offsetof(struct __sk_buff, cb[0]) + 256),
                        BPF_EXIT_INSN(),
                },
                .errstr = "invalid bpf_context access",
+               .errstr_unpriv = "",
                .result = REJECT,
                .prog_type = BPF_PROG_TYPE_SCHED_ACT,
        },
@@ -803,6 +834,8 @@ static struct bpf_test tests[] = {
                        BPF_EXIT_INSN(),
                },
                .result = ACCEPT,
+               .errstr_unpriv = "R1 leaks addr",
+               .result_unpriv = REJECT,
        },
        {
                "write skb fields from tc_cls_act prog",
@@ -819,6 +852,8 @@ static struct bpf_test tests[] = {
                                    offsetof(struct __sk_buff, cb[3])),
                        BPF_EXIT_INSN(),
                },
+               .errstr_unpriv = "",
+               .result_unpriv = REJECT,
                .result = ACCEPT,
                .prog_type = BPF_PROG_TYPE_SCHED_CLS,
        },
@@ -881,6 +916,270 @@ static struct bpf_test tests[] = {
                .result = REJECT,
                .errstr = "invalid stack off=0 size=8",
        },
+       {
+               "unpriv: return pointer",
+               .insns = {
+                       BPF_MOV64_REG(BPF_REG_0, BPF_REG_10),
+                       BPF_EXIT_INSN(),
+               },
+               .result = ACCEPT,
+               .result_unpriv = REJECT,
+               .errstr_unpriv = "R0 leaks addr",
+       },
+       {
+               "unpriv: add const to pointer",
+               .insns = {
+                       BPF_ALU64_IMM(BPF_ADD, BPF_REG_1, 8),
+                       BPF_MOV64_IMM(BPF_REG_0, 0),
+                       BPF_EXIT_INSN(),
+               },
+               .result = ACCEPT,
+               .result_unpriv = REJECT,
+               .errstr_unpriv = "R1 pointer arithmetic",
+       },
+       {
+               "unpriv: add pointer to pointer",
+               .insns = {
+                       BPF_ALU64_REG(BPF_ADD, BPF_REG_1, BPF_REG_10),
+                       BPF_MOV64_IMM(BPF_REG_0, 0),
+                       BPF_EXIT_INSN(),
+               },
+               .result = ACCEPT,
+               .result_unpriv = REJECT,
+               .errstr_unpriv = "R1 pointer arithmetic",
+       },
+       {
+               "unpriv: neg pointer",
+               .insns = {
+                       BPF_ALU64_IMM(BPF_NEG, BPF_REG_1, 0),
+                       BPF_MOV64_IMM(BPF_REG_0, 0),
+                       BPF_EXIT_INSN(),
+               },
+               .result = ACCEPT,
+               .result_unpriv = REJECT,
+               .errstr_unpriv = "R1 pointer arithmetic",
+       },
+       {
+               "unpriv: cmp pointer with const",
+               .insns = {
+                       BPF_JMP_IMM(BPF_JEQ, BPF_REG_1, 0, 0),
+                       BPF_MOV64_IMM(BPF_REG_0, 0),
+                       BPF_EXIT_INSN(),
+               },
+               .result = ACCEPT,
+               .result_unpriv = REJECT,
+               .errstr_unpriv = "R1 pointer comparison",
+       },
+       {
+               "unpriv: cmp pointer with pointer",
+               .insns = {
+                       BPF_JMP_REG(BPF_JEQ, BPF_REG_1, BPF_REG_10, 0),
+                       BPF_MOV64_IMM(BPF_REG_0, 0),
+                       BPF_EXIT_INSN(),
+               },
+               .result = ACCEPT,
+               .result_unpriv = REJECT,
+               .errstr_unpriv = "R10 pointer comparison",
+       },
+       {
+               "unpriv: check that printk is disallowed",
+               .insns = {
+                       BPF_ST_MEM(BPF_DW, BPF_REG_10, -8, 0),
+                       BPF_MOV64_REG(BPF_REG_1, BPF_REG_10),
+                       BPF_ALU64_IMM(BPF_ADD, BPF_REG_1, -8),
+                       BPF_MOV64_IMM(BPF_REG_2, 8),
+                       BPF_MOV64_REG(BPF_REG_3, BPF_REG_1),
+                       BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_trace_printk),
+                       BPF_MOV64_IMM(BPF_REG_0, 0),
+                       BPF_EXIT_INSN(),
+               },
+               .errstr_unpriv = "unknown func 6",
+               .result_unpriv = REJECT,
+               .result = ACCEPT,
+       },
+       {
+               "unpriv: pass pointer to helper function",
+               .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_MOV64_REG(BPF_REG_3, BPF_REG_2),
+                       BPF_MOV64_REG(BPF_REG_4, BPF_REG_2),
+                       BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_map_update_elem),
+                       BPF_MOV64_IMM(BPF_REG_0, 0),
+                       BPF_EXIT_INSN(),
+               },
+               .fixup = {3},
+               .errstr_unpriv = "R4 leaks addr",
+               .result_unpriv = REJECT,
+               .result = ACCEPT,
+       },
+       {
+               "unpriv: indirectly pass pointer on stack to helper function",
+               .insns = {
+                       BPF_STX_MEM(BPF_DW, BPF_REG_10, BPF_REG_10, -8),
+                       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_MOV64_IMM(BPF_REG_0, 0),
+                       BPF_EXIT_INSN(),
+               },
+               .fixup = {3},
+               .errstr = "invalid indirect read from stack off -8+0 size 8",
+               .result = REJECT,
+       },
+       {
+               "unpriv: mangle pointer on stack 1",
+               .insns = {
+                       BPF_STX_MEM(BPF_DW, BPF_REG_10, BPF_REG_10, -8),
+                       BPF_ST_MEM(BPF_W, BPF_REG_10, -8, 0),
+                       BPF_MOV64_IMM(BPF_REG_0, 0),
+                       BPF_EXIT_INSN(),
+               },
+               .errstr_unpriv = "attempt to corrupt spilled",
+               .result_unpriv = REJECT,
+               .result = ACCEPT,
+       },
+       {
+               "unpriv: mangle pointer on stack 2",
+               .insns = {
+                       BPF_STX_MEM(BPF_DW, BPF_REG_10, BPF_REG_10, -8),
+                       BPF_ST_MEM(BPF_B, BPF_REG_10, -1, 0),
+                       BPF_MOV64_IMM(BPF_REG_0, 0),
+                       BPF_EXIT_INSN(),
+               },
+               .errstr_unpriv = "attempt to corrupt spilled",
+               .result_unpriv = REJECT,
+               .result = ACCEPT,
+       },
+       {
+               "unpriv: read pointer from stack in small chunks",
+               .insns = {
+                       BPF_STX_MEM(BPF_DW, BPF_REG_10, BPF_REG_10, -8),
+                       BPF_LDX_MEM(BPF_W, BPF_REG_0, BPF_REG_10, -8),
+                       BPF_MOV64_IMM(BPF_REG_0, 0),
+                       BPF_EXIT_INSN(),
+               },
+               .errstr = "invalid size",
+               .result = REJECT,
+       },
+       {
+               "unpriv: write pointer into ctx",
+               .insns = {
+                       BPF_STX_MEM(BPF_DW, BPF_REG_1, BPF_REG_1, 0),
+                       BPF_MOV64_IMM(BPF_REG_0, 0),
+                       BPF_EXIT_INSN(),
+               },
+               .errstr_unpriv = "R1 leaks addr",
+               .result_unpriv = REJECT,
+               .errstr = "invalid bpf_context access",
+               .result = REJECT,
+       },
+       {
+               "unpriv: write pointer into map elem value",
+               .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, 1),
+                       BPF_STX_MEM(BPF_DW, BPF_REG_0, BPF_REG_0, 0),
+                       BPF_EXIT_INSN(),
+               },
+               .fixup = {3},
+               .errstr_unpriv = "R0 leaks addr",
+               .result_unpriv = REJECT,
+               .result = ACCEPT,
+       },
+       {
+               "unpriv: partial copy of pointer",
+               .insns = {
+                       BPF_MOV32_REG(BPF_REG_1, BPF_REG_10),
+                       BPF_MOV64_IMM(BPF_REG_0, 0),
+                       BPF_EXIT_INSN(),
+               },
+               .errstr_unpriv = "R10 partial copy",
+               .result_unpriv = REJECT,
+               .result = ACCEPT,
+       },
+       {
+               "unpriv: pass pointer to tail_call",
+               .insns = {
+                       BPF_MOV64_REG(BPF_REG_3, BPF_REG_1),
+                       BPF_LD_MAP_FD(BPF_REG_2, 0),
+                       BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_tail_call),
+                       BPF_MOV64_IMM(BPF_REG_0, 0),
+                       BPF_EXIT_INSN(),
+               },
+               .prog_array_fixup = {1},
+               .errstr_unpriv = "R3 leaks addr into helper",
+               .result_unpriv = REJECT,
+               .result = ACCEPT,
+       },
+       {
+               "unpriv: cmp map pointer with zero",
+               .insns = {
+                       BPF_MOV64_IMM(BPF_REG_1, 0),
+                       BPF_LD_MAP_FD(BPF_REG_1, 0),
+                       BPF_JMP_IMM(BPF_JEQ, BPF_REG_1, 0, 0),
+                       BPF_MOV64_IMM(BPF_REG_0, 0),
+                       BPF_EXIT_INSN(),
+               },
+               .fixup = {1},
+               .errstr_unpriv = "R1 pointer comparison",
+               .result_unpriv = REJECT,
+               .result = ACCEPT,
+       },
+       {
+               "unpriv: write into frame pointer",
+               .insns = {
+                       BPF_MOV64_REG(BPF_REG_10, BPF_REG_1),
+                       BPF_MOV64_IMM(BPF_REG_0, 0),
+                       BPF_EXIT_INSN(),
+               },
+               .errstr = "frame pointer is read only",
+               .result = REJECT,
+       },
+       {
+               "unpriv: cmp of frame pointer",
+               .insns = {
+                       BPF_JMP_IMM(BPF_JEQ, BPF_REG_10, 0, 0),
+                       BPF_MOV64_IMM(BPF_REG_0, 0),
+                       BPF_EXIT_INSN(),
+               },
+               .errstr_unpriv = "R10 pointer comparison",
+               .result_unpriv = REJECT,
+               .result = ACCEPT,
+       },
+       {
+               "unpriv: cmp of stack pointer",
+               .insns = {
+                       BPF_MOV64_REG(BPF_REG_2, BPF_REG_10),
+                       BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -8),
+                       BPF_JMP_IMM(BPF_JEQ, BPF_REG_2, 0, 0),
+                       BPF_MOV64_IMM(BPF_REG_0, 0),
+                       BPF_EXIT_INSN(),
+               },
+               .errstr_unpriv = "R2 pointer comparison",
+               .result_unpriv = REJECT,
+               .result = ACCEPT,
+       },
+       {
+               "unpriv: obfuscate stack pointer",
+               .insns = {
+                       BPF_MOV64_REG(BPF_REG_2, BPF_REG_10),
+                       BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -8),
+                       BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -8),
+                       BPF_MOV64_IMM(BPF_REG_0, 0),
+                       BPF_EXIT_INSN(),
+               },
+               .errstr_unpriv = "R2 pointer arithmetic",
+               .result_unpriv = REJECT,
+               .result = ACCEPT,
+       },
 };
 
 static int probe_filter_length(struct bpf_insn *fp)
@@ -896,13 +1195,24 @@ static int probe_filter_length(struct bpf_insn *fp)
 
 static int create_map(void)
 {
-       long long key, value = 0;
        int map_fd;
 
-       map_fd = bpf_create_map(BPF_MAP_TYPE_HASH, sizeof(key), sizeof(value), 1024);
-       if (map_fd < 0) {
+       map_fd = bpf_create_map(BPF_MAP_TYPE_HASH,
+                               sizeof(long long), sizeof(long long), 1024);
+       if (map_fd < 0)
                printf("failed to create map '%s'\n", strerror(errno));
-       }
+
+       return map_fd;
+}
+
+static int create_prog_array(void)
+{
+       int map_fd;
+
+       map_fd = bpf_create_map(BPF_MAP_TYPE_PROG_ARRAY,
+                               sizeof(int), sizeof(int), 4);
+       if (map_fd < 0)
+               printf("failed to create prog_array '%s'\n", strerror(errno));
 
        return map_fd;
 }
@@ -910,13 +1220,17 @@ static int create_map(void)
 static int test(void)
 {
        int prog_fd, i, pass_cnt = 0, err_cnt = 0;
+       bool unpriv = geteuid() != 0;
 
        for (i = 0; i < ARRAY_SIZE(tests); i++) {
                struct bpf_insn *prog = tests[i].insns;
                int prog_type = tests[i].prog_type;
                int prog_len = probe_filter_length(prog);
                int *fixup = tests[i].fixup;
-               int map_fd = -1;
+               int *prog_array_fixup = tests[i].prog_array_fixup;
+               int expected_result;
+               const char *expected_errstr;
+               int map_fd = -1, prog_array_fd = -1;
 
                if (*fixup) {
                        map_fd = create_map();
@@ -926,13 +1240,31 @@ static int test(void)
                                fixup++;
                        } while (*fixup);
                }
+               if (*prog_array_fixup) {
+                       prog_array_fd = create_prog_array();
+
+                       do {
+                               prog[*prog_array_fixup].imm = prog_array_fd;
+                               prog_array_fixup++;
+                       } while (*prog_array_fixup);
+               }
                printf("#%d %s ", i, tests[i].descr);
 
                prog_fd = bpf_prog_load(prog_type ?: BPF_PROG_TYPE_SOCKET_FILTER,
                                        prog, prog_len * sizeof(struct bpf_insn),
                                        "GPL", 0);
 
-               if (tests[i].result == ACCEPT) {
+               if (unpriv && tests[i].result_unpriv != UNDEF)
+                       expected_result = tests[i].result_unpriv;
+               else
+                       expected_result = tests[i].result;
+
+               if (unpriv && tests[i].errstr_unpriv)
+                       expected_errstr = tests[i].errstr_unpriv;
+               else
+                       expected_errstr = tests[i].errstr;
+
+               if (expected_result == ACCEPT) {
                        if (prog_fd < 0) {
                                printf("FAIL\nfailed to load prog '%s'\n",
                                       strerror(errno));
@@ -947,7 +1279,7 @@ static int test(void)
                                err_cnt++;
                                goto fail;
                        }
-                       if (strstr(bpf_log_buf, tests[i].errstr) == 0) {
+                       if (strstr(bpf_log_buf, expected_errstr) == 0) {
                                printf("FAIL\nunexpected error message: %s",
                                       bpf_log_buf);
                                err_cnt++;
@@ -960,6 +1292,8 @@ static int test(void)
 fail:
                if (map_fd >= 0)
                        close(map_fd);
+               if (prog_array_fd >= 0)
+                       close(prog_array_fd);
                close(prog_fd);
 
        }
@@ -970,5 +1304,8 @@ fail:
 
 int main(void)
 {
+       struct rlimit r = {1 << 20, 1 << 20};
+
+       setrlimit(RLIMIT_MEMLOCK, &r);
        return test();
 }