#include <linux/vmalloc.h>
#include <linux/stringify.h>
+#include "disasm.h"
+
+static const struct bpf_verifier_ops * const bpf_verifier_ops[] = {
+#define BPF_PROG_TYPE(_id, _name) \
+ [_id] = & _name ## _verifier_ops,
+#define BPF_MAP_TYPE(_id, _ops)
+#include <linux/bpf_types.h>
+#undef BPF_PROG_TYPE
+#undef BPF_MAP_TYPE
+};
+
/* bpf_check() is a static code analyzer that walks eBPF program
* instruction by instruction and updates register/stack state.
* All paths of conditional branches are analyzed until 'bpf_exit' insn.
int access_size;
};
-/* verbose verifier prints what it's seeing
- * bpf_check() is called under lock, so no race to access these global vars
- */
-static u32 log_level, log_size, log_len;
-static char *log_buf;
-
static DEFINE_MUTEX(bpf_verifier_lock);
/* log_level controls verbosity level of eBPF verifier.
* verbose() is used to dump the verification trace to the log, so the user
* can figure out what's wrong with the program
*/
-static __printf(1, 2) void verbose(const char *fmt, ...)
+static __printf(2, 3) void verbose(struct bpf_verifier_env *env,
+ const char *fmt, ...)
{
+ struct bpf_verifer_log *log = &env->log;
+ unsigned int n;
va_list args;
- if (log_level == 0 || log_len >= log_size - 1)
+ if (!log->level || !log->ubuf || bpf_verifier_log_full(log))
return;
va_start(args, fmt);
- log_len += vscnprintf(log_buf + log_len, log_size - log_len, fmt, args);
+ n = vscnprintf(log->kbuf, BPF_VERIFIER_TMP_LOG_SIZE, fmt, args);
va_end(args);
+
+ WARN_ONCE(n >= BPF_VERIFIER_TMP_LOG_SIZE - 1,
+ "verifier log line truncated - local buffer too short\n");
+
+ n = min(log->len_total - log->len_used - 1, n);
+ log->kbuf[n] = '\0';
+
+ if (!copy_to_user(log->ubuf + log->len_used, log->kbuf, n + 1))
+ log->len_used += n;
+ else
+ log->ubuf = NULL;
+}
+
+static bool type_is_pkt_pointer(enum bpf_reg_type type)
+{
+ return type == PTR_TO_PACKET ||
+ type == PTR_TO_PACKET_META;
}
/* string representation of 'enum bpf_reg_type' */
[PTR_TO_MAP_VALUE_OR_NULL] = "map_value_or_null",
[PTR_TO_STACK] = "fp",
[PTR_TO_PACKET] = "pkt",
+ [PTR_TO_PACKET_META] = "pkt_meta",
[PTR_TO_PACKET_END] = "pkt_end",
};
-#define __BPF_FUNC_STR_FN(x) [BPF_FUNC_ ## x] = __stringify(bpf_ ## x)
-static const char * const func_id_str[] = {
- __BPF_FUNC_MAPPER(__BPF_FUNC_STR_FN)
-};
-#undef __BPF_FUNC_STR_FN
-
-static const char *func_id_name(int id)
-{
- BUILD_BUG_ON(ARRAY_SIZE(func_id_str) != __BPF_FUNC_MAX_ID);
-
- if (id >= 0 && id < __BPF_FUNC_MAX_ID && func_id_str[id])
- return func_id_str[id];
- else
- return "unknown";
-}
-
-static void print_verifier_state(struct bpf_verifier_state *state)
+static void print_verifier_state(struct bpf_verifier_env *env,
+ struct bpf_verifier_state *state)
{
struct bpf_reg_state *reg;
enum bpf_reg_type t;
t = reg->type;
if (t == NOT_INIT)
continue;
- verbose(" R%d=%s", i, reg_type_str[t]);
+ verbose(env, " R%d=%s", i, reg_type_str[t]);
if ((t == SCALAR_VALUE || t == PTR_TO_STACK) &&
tnum_is_const(reg->var_off)) {
/* reg->off should be 0 for SCALAR_VALUE */
- verbose("%lld", reg->var_off.value + reg->off);
+ verbose(env, "%lld", reg->var_off.value + reg->off);
} else {
- verbose("(id=%d", reg->id);
+ verbose(env, "(id=%d", reg->id);
if (t != SCALAR_VALUE)
- verbose(",off=%d", reg->off);
- if (t == PTR_TO_PACKET)
- verbose(",r=%d", reg->range);
+ verbose(env, ",off=%d", reg->off);
+ if (type_is_pkt_pointer(t))
+ verbose(env, ",r=%d", reg->range);
else if (t == CONST_PTR_TO_MAP ||
t == PTR_TO_MAP_VALUE ||
t == PTR_TO_MAP_VALUE_OR_NULL)
- verbose(",ks=%d,vs=%d",
+ verbose(env, ",ks=%d,vs=%d",
reg->map_ptr->key_size,
reg->map_ptr->value_size);
if (tnum_is_const(reg->var_off)) {
* could be a pointer whose offset is too big
* for reg->off
*/
- verbose(",imm=%llx", reg->var_off.value);
+ verbose(env, ",imm=%llx", reg->var_off.value);
} else {
if (reg->smin_value != reg->umin_value &&
reg->smin_value != S64_MIN)
- verbose(",smin_value=%lld",
+ verbose(env, ",smin_value=%lld",
(long long)reg->smin_value);
if (reg->smax_value != reg->umax_value &&
reg->smax_value != S64_MAX)
- verbose(",smax_value=%lld",
+ verbose(env, ",smax_value=%lld",
(long long)reg->smax_value);
if (reg->umin_value != 0)
- verbose(",umin_value=%llu",
+ verbose(env, ",umin_value=%llu",
(unsigned long long)reg->umin_value);
if (reg->umax_value != U64_MAX)
- verbose(",umax_value=%llu",
+ verbose(env, ",umax_value=%llu",
(unsigned long long)reg->umax_value);
if (!tnum_is_unknown(reg->var_off)) {
char tn_buf[48];
tnum_strn(tn_buf, sizeof(tn_buf), reg->var_off);
- verbose(",var_off=%s", tn_buf);
+ verbose(env, ",var_off=%s", tn_buf);
}
}
- verbose(")");
+ verbose(env, ")");
}
}
- for (i = 0; i < MAX_BPF_STACK; i += BPF_REG_SIZE) {
- if (state->stack_slot_type[i] == STACK_SPILL)
- verbose(" fp%d=%s", -MAX_BPF_STACK + i,
- reg_type_str[state->spilled_regs[i / BPF_REG_SIZE].type]);
+ for (i = 0; i < state->allocated_stack / BPF_REG_SIZE; i++) {
+ if (state->stack[i].slot_type[0] == STACK_SPILL)
+ verbose(env, " fp%d=%s",
+ -MAX_BPF_STACK + i * BPF_REG_SIZE,
+ reg_type_str[state->stack[i].spilled_ptr.type]);
}
- verbose("\n");
+ verbose(env, "\n");
}
-static const char *const bpf_class_string[] = {
- [BPF_LD] = "ld",
- [BPF_LDX] = "ldx",
- [BPF_ST] = "st",
- [BPF_STX] = "stx",
- [BPF_ALU] = "alu",
- [BPF_JMP] = "jmp",
- [BPF_RET] = "BUG",
- [BPF_ALU64] = "alu64",
-};
-
-static const char *const bpf_alu_string[16] = {
- [BPF_ADD >> 4] = "+=",
- [BPF_SUB >> 4] = "-=",
- [BPF_MUL >> 4] = "*=",
- [BPF_DIV >> 4] = "/=",
- [BPF_OR >> 4] = "|=",
- [BPF_AND >> 4] = "&=",
- [BPF_LSH >> 4] = "<<=",
- [BPF_RSH >> 4] = ">>=",
- [BPF_NEG >> 4] = "neg",
- [BPF_MOD >> 4] = "%=",
- [BPF_XOR >> 4] = "^=",
- [BPF_MOV >> 4] = "=",
- [BPF_ARSH >> 4] = "s>>=",
- [BPF_END >> 4] = "endian",
-};
-
-static const char *const bpf_ldst_string[] = {
- [BPF_W >> 3] = "u32",
- [BPF_H >> 3] = "u16",
- [BPF_B >> 3] = "u8",
- [BPF_DW >> 3] = "u64",
-};
-
-static const char *const bpf_jmp_string[16] = {
- [BPF_JA >> 4] = "jmp",
- [BPF_JEQ >> 4] = "==",
- [BPF_JGT >> 4] = ">",
- [BPF_JLT >> 4] = "<",
- [BPF_JGE >> 4] = ">=",
- [BPF_JLE >> 4] = "<=",
- [BPF_JSET >> 4] = "&",
- [BPF_JNE >> 4] = "!=",
- [BPF_JSGT >> 4] = "s>",
- [BPF_JSLT >> 4] = "s<",
- [BPF_JSGE >> 4] = "s>=",
- [BPF_JSLE >> 4] = "s<=",
- [BPF_CALL >> 4] = "call",
- [BPF_EXIT >> 4] = "exit",
-};
+static int copy_stack_state(struct bpf_verifier_state *dst,
+ const struct bpf_verifier_state *src)
+{
+ if (!src->stack)
+ return 0;
+ if (WARN_ON_ONCE(dst->allocated_stack < src->allocated_stack)) {
+ /* internal bug, make state invalid to reject the program */
+ memset(dst, 0, sizeof(*dst));
+ return -EFAULT;
+ }
+ memcpy(dst->stack, src->stack,
+ sizeof(*src->stack) * (src->allocated_stack / BPF_REG_SIZE));
+ return 0;
+}
-static void print_bpf_insn(const struct bpf_verifier_env *env,
- const struct bpf_insn *insn)
+/* do_check() starts with zero-sized stack in struct bpf_verifier_state to
+ * make it consume minimal amount of memory. check_stack_write() access from
+ * the program calls into realloc_verifier_state() to grow the stack size.
+ * Note there is a non-zero 'parent' pointer inside bpf_verifier_state
+ * which this function copies over. It points to previous bpf_verifier_state
+ * which is never reallocated
+ */
+static int realloc_verifier_state(struct bpf_verifier_state *state, int size,
+ bool copy_old)
{
- u8 class = BPF_CLASS(insn->code);
-
- if (class == BPF_ALU || class == BPF_ALU64) {
- if (BPF_SRC(insn->code) == BPF_X)
- verbose("(%02x) %sr%d %s %sr%d\n",
- insn->code, class == BPF_ALU ? "(u32) " : "",
- insn->dst_reg,
- bpf_alu_string[BPF_OP(insn->code) >> 4],
- class == BPF_ALU ? "(u32) " : "",
- insn->src_reg);
- else
- verbose("(%02x) %sr%d %s %s%d\n",
- insn->code, class == BPF_ALU ? "(u32) " : "",
- insn->dst_reg,
- bpf_alu_string[BPF_OP(insn->code) >> 4],
- class == BPF_ALU ? "(u32) " : "",
- insn->imm);
- } else if (class == BPF_STX) {
- if (BPF_MODE(insn->code) == BPF_MEM)
- verbose("(%02x) *(%s *)(r%d %+d) = r%d\n",
- insn->code,
- bpf_ldst_string[BPF_SIZE(insn->code) >> 3],
- insn->dst_reg,
- insn->off, insn->src_reg);
- else if (BPF_MODE(insn->code) == BPF_XADD)
- verbose("(%02x) lock *(%s *)(r%d %+d) += r%d\n",
- insn->code,
- bpf_ldst_string[BPF_SIZE(insn->code) >> 3],
- insn->dst_reg, insn->off,
- insn->src_reg);
- else
- verbose("BUG_%02x\n", insn->code);
- } else if (class == BPF_ST) {
- if (BPF_MODE(insn->code) != BPF_MEM) {
- verbose("BUG_st_%02x\n", insn->code);
- return;
- }
- verbose("(%02x) *(%s *)(r%d %+d) = %d\n",
- insn->code,
- bpf_ldst_string[BPF_SIZE(insn->code) >> 3],
- insn->dst_reg,
- insn->off, insn->imm);
- } else if (class == BPF_LDX) {
- if (BPF_MODE(insn->code) != BPF_MEM) {
- verbose("BUG_ldx_%02x\n", insn->code);
- return;
+ u32 old_size = state->allocated_stack;
+ struct bpf_stack_state *new_stack;
+ int slot = size / BPF_REG_SIZE;
+
+ if (size <= old_size || !size) {
+ if (copy_old)
+ return 0;
+ state->allocated_stack = slot * BPF_REG_SIZE;
+ if (!size && old_size) {
+ kfree(state->stack);
+ state->stack = NULL;
}
- verbose("(%02x) r%d = *(%s *)(r%d %+d)\n",
- insn->code, insn->dst_reg,
- bpf_ldst_string[BPF_SIZE(insn->code) >> 3],
- insn->src_reg, insn->off);
- } else if (class == BPF_LD) {
- if (BPF_MODE(insn->code) == BPF_ABS) {
- verbose("(%02x) r0 = *(%s *)skb[%d]\n",
- insn->code,
- bpf_ldst_string[BPF_SIZE(insn->code) >> 3],
- insn->imm);
- } else if (BPF_MODE(insn->code) == BPF_IND) {
- verbose("(%02x) r0 = *(%s *)skb[r%d + %d]\n",
- insn->code,
- bpf_ldst_string[BPF_SIZE(insn->code) >> 3],
- insn->src_reg, insn->imm);
- } else if (BPF_MODE(insn->code) == BPF_IMM &&
- BPF_SIZE(insn->code) == BPF_DW) {
- /* At this point, we already made sure that the second
- * part of the ldimm64 insn is accessible.
- */
- u64 imm = ((u64)(insn + 1)->imm << 32) | (u32)insn->imm;
- bool map_ptr = insn->src_reg == BPF_PSEUDO_MAP_FD;
+ return 0;
+ }
+ new_stack = kmalloc_array(slot, sizeof(struct bpf_stack_state),
+ GFP_KERNEL);
+ if (!new_stack)
+ return -ENOMEM;
+ if (copy_old) {
+ if (state->stack)
+ memcpy(new_stack, state->stack,
+ sizeof(*new_stack) * (old_size / BPF_REG_SIZE));
+ memset(new_stack + old_size / BPF_REG_SIZE, 0,
+ sizeof(*new_stack) * (size - old_size) / BPF_REG_SIZE);
+ }
+ state->allocated_stack = slot * BPF_REG_SIZE;
+ kfree(state->stack);
+ state->stack = new_stack;
+ return 0;
+}
- if (map_ptr && !env->allow_ptr_leaks)
- imm = 0;
+static void free_verifier_state(struct bpf_verifier_state *state,
+ bool free_self)
+{
+ kfree(state->stack);
+ if (free_self)
+ kfree(state);
+}
- verbose("(%02x) r%d = 0x%llx\n", insn->code,
- insn->dst_reg, (unsigned long long)imm);
- } else {
- verbose("BUG_ld_%02x\n", insn->code);
- return;
- }
- } else if (class == BPF_JMP) {
- u8 opcode = BPF_OP(insn->code);
+/* copy verifier state from src to dst growing dst stack space
+ * when necessary to accommodate larger src stack
+ */
+static int copy_verifier_state(struct bpf_verifier_state *dst,
+ const struct bpf_verifier_state *src)
+{
+ int err;
- if (opcode == BPF_CALL) {
- verbose("(%02x) call %s#%d\n", insn->code,
- func_id_name(insn->imm), insn->imm);
- } else if (insn->code == (BPF_JMP | BPF_JA)) {
- verbose("(%02x) goto pc%+d\n",
- insn->code, insn->off);
- } else if (insn->code == (BPF_JMP | BPF_EXIT)) {
- verbose("(%02x) exit\n", insn->code);
- } else if (BPF_SRC(insn->code) == BPF_X) {
- verbose("(%02x) if r%d %s r%d goto pc%+d\n",
- insn->code, insn->dst_reg,
- bpf_jmp_string[BPF_OP(insn->code) >> 4],
- insn->src_reg, insn->off);
- } else {
- verbose("(%02x) if r%d %s 0x%x goto pc%+d\n",
- insn->code, insn->dst_reg,
- bpf_jmp_string[BPF_OP(insn->code) >> 4],
- insn->imm, insn->off);
- }
- } else {
- verbose("(%02x) %s\n", insn->code, bpf_class_string[class]);
- }
+ err = realloc_verifier_state(dst, src->allocated_stack, false);
+ if (err)
+ return err;
+ memcpy(dst, src, offsetof(struct bpf_verifier_state, allocated_stack));
+ return copy_stack_state(dst, src);
}
-static int pop_stack(struct bpf_verifier_env *env, int *prev_insn_idx)
+static int pop_stack(struct bpf_verifier_env *env, int *prev_insn_idx,
+ int *insn_idx)
{
- struct bpf_verifier_stack_elem *elem;
- int insn_idx;
+ struct bpf_verifier_state *cur = env->cur_state;
+ struct bpf_verifier_stack_elem *elem, *head = env->head;
+ int err;
if (env->head == NULL)
- return -1;
+ return -ENOENT;
- memcpy(&env->cur_state, &env->head->st, sizeof(env->cur_state));
- insn_idx = env->head->insn_idx;
+ if (cur) {
+ err = copy_verifier_state(cur, &head->st);
+ if (err)
+ return err;
+ }
+ if (insn_idx)
+ *insn_idx = head->insn_idx;
if (prev_insn_idx)
- *prev_insn_idx = env->head->prev_insn_idx;
- elem = env->head->next;
- kfree(env->head);
+ *prev_insn_idx = head->prev_insn_idx;
+ elem = head->next;
+ free_verifier_state(&head->st, false);
+ kfree(head);
env->head = elem;
env->stack_size--;
- return insn_idx;
+ return 0;
}
static struct bpf_verifier_state *push_stack(struct bpf_verifier_env *env,
int insn_idx, int prev_insn_idx)
{
+ struct bpf_verifier_state *cur = env->cur_state;
struct bpf_verifier_stack_elem *elem;
+ int err;
- elem = kmalloc(sizeof(struct bpf_verifier_stack_elem), GFP_KERNEL);
+ elem = kzalloc(sizeof(struct bpf_verifier_stack_elem), GFP_KERNEL);
if (!elem)
goto err;
- memcpy(&elem->st, &env->cur_state, sizeof(env->cur_state));
elem->insn_idx = insn_idx;
elem->prev_insn_idx = prev_insn_idx;
elem->next = env->head;
env->head = elem;
env->stack_size++;
+ err = copy_verifier_state(&elem->st, cur);
+ if (err)
+ goto err;
if (env->stack_size > BPF_COMPLEXITY_LIMIT_STACK) {
- verbose("BPF program is too complex\n");
+ verbose(env, "BPF program is too complex\n");
goto err;
}
return &elem->st;
err:
/* pop all elements and return */
- while (pop_stack(env, NULL) >= 0);
+ while (!pop_stack(env, NULL, NULL));
return NULL;
}
__mark_reg_known(reg, 0);
}
-static void mark_reg_known_zero(struct bpf_reg_state *regs, u32 regno)
+static void mark_reg_known_zero(struct bpf_verifier_env *env,
+ struct bpf_reg_state *regs, u32 regno)
{
if (WARN_ON(regno >= MAX_BPF_REG)) {
- verbose("mark_reg_known_zero(regs, %u)\n", regno);
+ verbose(env, "mark_reg_known_zero(regs, %u)\n", regno);
/* Something bad happened, let's kill all regs */
for (regno = 0; regno < MAX_BPF_REG; regno++)
__mark_reg_not_init(regs + regno);
__mark_reg_known_zero(regs + regno);
}
+static bool reg_is_pkt_pointer(const struct bpf_reg_state *reg)
+{
+ return type_is_pkt_pointer(reg->type);
+}
+
+static bool reg_is_pkt_pointer_any(const struct bpf_reg_state *reg)
+{
+ return reg_is_pkt_pointer(reg) ||
+ reg->type == PTR_TO_PACKET_END;
+}
+
+/* Unmodified PTR_TO_PACKET[_META,_END] register from ctx access. */
+static bool reg_is_init_pkt_pointer(const struct bpf_reg_state *reg,
+ enum bpf_reg_type which)
+{
+ /* The register can already have a range from prior markings.
+ * This is fine as long as it hasn't been advanced from its
+ * origin.
+ */
+ return reg->type == which &&
+ reg->id == 0 &&
+ reg->off == 0 &&
+ tnum_equals_const(reg->var_off, 0);
+}
+
/* Attempts to improve min/max values based on var_off information */
static void __update_reg_bounds(struct bpf_reg_state *reg)
{
__mark_reg_unbounded(reg);
}
-static void mark_reg_unknown(struct bpf_reg_state *regs, u32 regno)
+static void mark_reg_unknown(struct bpf_verifier_env *env,
+ struct bpf_reg_state *regs, u32 regno)
{
if (WARN_ON(regno >= MAX_BPF_REG)) {
- verbose("mark_reg_unknown(regs, %u)\n", regno);
+ verbose(env, "mark_reg_unknown(regs, %u)\n", regno);
/* Something bad happened, let's kill all regs */
for (regno = 0; regno < MAX_BPF_REG; regno++)
__mark_reg_not_init(regs + regno);
reg->type = NOT_INIT;
}
-static void mark_reg_not_init(struct bpf_reg_state *regs, u32 regno)
+static void mark_reg_not_init(struct bpf_verifier_env *env,
+ struct bpf_reg_state *regs, u32 regno)
{
if (WARN_ON(regno >= MAX_BPF_REG)) {
- verbose("mark_reg_not_init(regs, %u)\n", regno);
+ verbose(env, "mark_reg_not_init(regs, %u)\n", regno);
/* Something bad happened, let's kill all regs */
for (regno = 0; regno < MAX_BPF_REG; regno++)
__mark_reg_not_init(regs + regno);
__mark_reg_not_init(regs + regno);
}
-static void init_reg_state(struct bpf_reg_state *regs)
+static void init_reg_state(struct bpf_verifier_env *env,
+ struct bpf_reg_state *regs)
{
int i;
for (i = 0; i < MAX_BPF_REG; i++) {
- mark_reg_not_init(regs, i);
+ mark_reg_not_init(env, regs, i);
regs[i].live = REG_LIVE_NONE;
}
/* frame pointer */
regs[BPF_REG_FP].type = PTR_TO_STACK;
- mark_reg_known_zero(regs, BPF_REG_FP);
+ mark_reg_known_zero(env, regs, BPF_REG_FP);
/* 1st arg to a function */
regs[BPF_REG_1].type = PTR_TO_CTX;
- mark_reg_known_zero(regs, BPF_REG_1);
+ mark_reg_known_zero(env, regs, BPF_REG_1);
}
enum reg_arg_type {
static int check_reg_arg(struct bpf_verifier_env *env, u32 regno,
enum reg_arg_type t)
{
- struct bpf_reg_state *regs = env->cur_state.regs;
+ struct bpf_reg_state *regs = env->cur_state->regs;
if (regno >= MAX_BPF_REG) {
- verbose("R%d is invalid\n", regno);
+ verbose(env, "R%d is invalid\n", regno);
return -EINVAL;
}
if (t == SRC_OP) {
/* check whether register used as source operand can be read */
if (regs[regno].type == NOT_INIT) {
- verbose("R%d !read_ok\n", regno);
+ verbose(env, "R%d !read_ok\n", regno);
return -EACCES;
}
- mark_reg_read(&env->cur_state, regno);
+ mark_reg_read(env->cur_state, regno);
} else {
/* check whether register used as dest operand can be written to */
if (regno == BPF_REG_FP) {
- verbose("frame pointer is read only\n");
+ verbose(env, "frame pointer is read only\n");
return -EACCES;
}
regs[regno].live |= REG_LIVE_WRITTEN;
if (t == DST_OP)
- mark_reg_unknown(regs, regno);
+ mark_reg_unknown(env, regs, regno);
}
return 0;
}
case PTR_TO_STACK:
case PTR_TO_CTX:
case PTR_TO_PACKET:
+ case PTR_TO_PACKET_META:
case PTR_TO_PACKET_END:
case CONST_PTR_TO_MAP:
return true;
/* check_stack_read/write functions track spill/fill of registers,
* stack boundary and alignment are checked in check_mem_access()
*/
-static int check_stack_write(struct bpf_verifier_state *state, int off,
+static int check_stack_write(struct bpf_verifier_env *env,
+ struct bpf_verifier_state *state, int off,
int size, int value_regno)
{
- int i, spi = (MAX_BPF_STACK + off) / BPF_REG_SIZE;
+ int i, slot = -off - 1, spi = slot / BPF_REG_SIZE, err;
+
+ err = realloc_verifier_state(state, round_up(slot + 1, BPF_REG_SIZE),
+ true);
+ if (err)
+ return err;
/* caller checked that off % size == 0 and -MAX_BPF_STACK <= off < 0,
* so it's aligned access and [off, off + size) are within stack limits
*/
+ if (!env->allow_ptr_leaks &&
+ state->stack[spi].slot_type[0] == STACK_SPILL &&
+ size != BPF_REG_SIZE) {
+ verbose(env, "attempt to corrupt spilled pointer on stack\n");
+ return -EACCES;
+ }
if (value_regno >= 0 &&
is_spillable_regtype(state->regs[value_regno].type)) {
/* register containing pointer is being spilled into stack */
if (size != BPF_REG_SIZE) {
- verbose("invalid size of register spill\n");
+ verbose(env, "invalid size of register spill\n");
return -EACCES;
}
/* save register state */
- state->spilled_regs[spi] = state->regs[value_regno];
- state->spilled_regs[spi].live |= REG_LIVE_WRITTEN;
+ state->stack[spi].spilled_ptr = state->regs[value_regno];
+ state->stack[spi].spilled_ptr.live |= REG_LIVE_WRITTEN;
for (i = 0; i < BPF_REG_SIZE; i++)
- state->stack_slot_type[MAX_BPF_STACK + off + i] = STACK_SPILL;
+ state->stack[spi].slot_type[i] = STACK_SPILL;
} else {
/* regular write of data into stack */
- state->spilled_regs[spi] = (struct bpf_reg_state) {};
+ state->stack[spi].spilled_ptr = (struct bpf_reg_state) {};
for (i = 0; i < size; i++)
- state->stack_slot_type[MAX_BPF_STACK + off + i] = STACK_MISC;
+ state->stack[spi].slot_type[(slot - i) % BPF_REG_SIZE] =
+ STACK_MISC;
}
return 0;
}
while (parent) {
/* if read wasn't screened by an earlier write ... */
- if (state->spilled_regs[slot].live & REG_LIVE_WRITTEN)
+ if (state->stack[slot].spilled_ptr.live & REG_LIVE_WRITTEN)
break;
/* ... then we depend on parent's value */
- parent->spilled_regs[slot].live |= REG_LIVE_READ;
+ parent->stack[slot].spilled_ptr.live |= REG_LIVE_READ;
state = parent;
parent = state->parent;
}
}
-static int check_stack_read(struct bpf_verifier_state *state, int off, int size,
+static int check_stack_read(struct bpf_verifier_env *env,
+ struct bpf_verifier_state *state, int off, int size,
int value_regno)
{
- u8 *slot_type;
- int i, spi;
+ int i, slot = -off - 1, spi = slot / BPF_REG_SIZE;
+ u8 *stype;
- slot_type = &state->stack_slot_type[MAX_BPF_STACK + off];
+ if (state->allocated_stack <= slot) {
+ verbose(env, "invalid read from stack off %d+0 size %d\n",
+ off, size);
+ return -EACCES;
+ }
+ stype = state->stack[spi].slot_type;
- if (slot_type[0] == STACK_SPILL) {
+ if (stype[0] == STACK_SPILL) {
if (size != BPF_REG_SIZE) {
- verbose("invalid size of register spill\n");
+ verbose(env, "invalid size of register spill\n");
return -EACCES;
}
for (i = 1; i < BPF_REG_SIZE; i++) {
- if (slot_type[i] != STACK_SPILL) {
- verbose("corrupted spill memory\n");
+ if (stype[(slot - i) % BPF_REG_SIZE] != STACK_SPILL) {
+ verbose(env, "corrupted spill memory\n");
return -EACCES;
}
}
- spi = (MAX_BPF_STACK + off) / BPF_REG_SIZE;
-
if (value_regno >= 0) {
/* restore register state from stack */
- state->regs[value_regno] = state->spilled_regs[spi];
+ state->regs[value_regno] = state->stack[spi].spilled_ptr;
mark_stack_slot_read(state, spi);
}
return 0;
} else {
for (i = 0; i < size; i++) {
- if (slot_type[i] != STACK_MISC) {
- verbose("invalid read from stack off %d+%d size %d\n",
+ if (stype[(slot - i) % BPF_REG_SIZE] != STACK_MISC) {
+ verbose(env, "invalid read from stack off %d+%d size %d\n",
off, i, size);
return -EACCES;
}
}
if (value_regno >= 0)
/* have read misc data from the stack */
- mark_reg_unknown(state->regs, value_regno);
+ mark_reg_unknown(env, state->regs, value_regno);
return 0;
}
}
static int __check_map_access(struct bpf_verifier_env *env, u32 regno, int off,
int size)
{
- struct bpf_map *map = env->cur_state.regs[regno].map_ptr;
+ struct bpf_reg_state *regs = cur_regs(env);
+ struct bpf_map *map = regs[regno].map_ptr;
if (off < 0 || size <= 0 || off + size > map->value_size) {
- verbose("invalid access to map value, value_size=%d off=%d size=%d\n",
+ verbose(env, "invalid access to map value, value_size=%d off=%d size=%d\n",
map->value_size, off, size);
return -EACCES;
}
/* check read/write into a map element with possible variable offset */
static int check_map_access(struct bpf_verifier_env *env, u32 regno,
- int off, int size)
+ int off, int size)
{
- struct bpf_verifier_state *state = &env->cur_state;
+ struct bpf_verifier_state *state = env->cur_state;
struct bpf_reg_state *reg = &state->regs[regno];
int err;
* need to try adding each of min_value and max_value to off
* to make sure our theoretical access will be safe.
*/
- if (log_level)
- print_verifier_state(state);
+ if (env->log.level)
+ print_verifier_state(env, state);
/* The minimum value is only important with signed
* comparisons where we can't assume the floor of a
* value is 0. If we are using signed variables for our
* will have a set floor within our range.
*/
if (reg->smin_value < 0) {
- verbose("R%d min value is negative, either use unsigned index or do a if (index >=0) check.\n",
+ verbose(env, "R%d min value is negative, either use unsigned index or do a if (index >=0) check.\n",
regno);
return -EACCES;
}
err = __check_map_access(env, regno, reg->smin_value + off, size);
if (err) {
- verbose("R%d min value is outside of the array range\n", regno);
+ verbose(env, "R%d min value is outside of the array range\n",
+ regno);
return err;
}
* If reg->umax_value + off could overflow, treat that as unbounded too.
*/
if (reg->umax_value >= BPF_MAX_VAR_OFF) {
- verbose("R%d unbounded memory access, make sure to bounds check any array access into a map\n",
+ verbose(env, "R%d unbounded memory access, make sure to bounds check any array access into a map\n",
regno);
return -EACCES;
}
err = __check_map_access(env, regno, reg->umax_value + off, size);
if (err)
- verbose("R%d max value is outside of the array range\n", regno);
+ verbose(env, "R%d max value is outside of the array range\n",
+ regno);
return err;
}
static int __check_packet_access(struct bpf_verifier_env *env, u32 regno,
int off, int size)
{
- struct bpf_reg_state *regs = env->cur_state.regs;
+ struct bpf_reg_state *regs = cur_regs(env);
struct bpf_reg_state *reg = ®s[regno];
if (off < 0 || size <= 0 || (u64)off + size > reg->range) {
- verbose("invalid access to packet, off=%d size=%d, R%d(id=%d,off=%d,r=%d)\n",
+ verbose(env, "invalid access to packet, off=%d size=%d, R%d(id=%d,off=%d,r=%d)\n",
off, size, regno, reg->id, reg->off, reg->range);
return -EACCES;
}
static int check_packet_access(struct bpf_verifier_env *env, u32 regno, int off,
int size)
{
- struct bpf_reg_state *regs = env->cur_state.regs;
+ struct bpf_reg_state *regs = cur_regs(env);
struct bpf_reg_state *reg = ®s[regno];
int err;
* detail to prove they're safe.
*/
if (reg->smin_value < 0) {
- verbose("R%d min value is negative, either use unsigned index or do a if (index >=0) check.\n",
+ verbose(env, "R%d min value is negative, either use unsigned index or do a if (index >=0) check.\n",
regno);
return -EACCES;
}
err = __check_packet_access(env, regno, off, size);
if (err) {
- verbose("R%d offset is outside of the packet\n", regno);
+ verbose(env, "R%d offset is outside of the packet\n", regno);
return err;
}
return err;
.reg_type = *reg_type,
};
- /* for analyzer ctx accesses are already validated and converted */
- if (env->analyzer_ops)
- return 0;
-
- if (env->prog->aux->ops->is_valid_access &&
- env->prog->aux->ops->is_valid_access(off, size, t, &info)) {
+ if (env->ops->is_valid_access &&
+ env->ops->is_valid_access(off, size, t, &info)) {
/* A non zero info.ctx_field_size indicates that this field is a
* candidate for later verifier transformation to load the whole
* field and then apply a mask when accessed with a narrower
* will only allow for whole field access and rejects any other
* type of narrower access.
*/
- env->insn_aux_data[insn_idx].ctx_field_size = info.ctx_field_size;
*reg_type = info.reg_type;
+ if (env->analyzer_ops)
+ return 0;
+
+ env->insn_aux_data[insn_idx].ctx_field_size = info.ctx_field_size;
/* remember the offset of last byte accessed in ctx */
if (env->prog->aux->max_ctx_offset < off + size)
env->prog->aux->max_ctx_offset = off + size;
return 0;
}
- verbose("invalid bpf_context access off=%d size=%d\n", off, size);
+ verbose(env, "invalid bpf_context access off=%d size=%d\n", off, size);
return -EACCES;
}
static bool is_pointer_value(struct bpf_verifier_env *env, int regno)
{
- return __is_pointer_value(env->allow_ptr_leaks, &env->cur_state.regs[regno]);
+ return __is_pointer_value(env->allow_ptr_leaks, cur_regs(env) + regno);
}
-static int check_pkt_ptr_alignment(const struct bpf_reg_state *reg,
+static int check_pkt_ptr_alignment(struct bpf_verifier_env *env,
+ const struct bpf_reg_state *reg,
int off, int size, bool strict)
{
struct tnum reg_off;
char tn_buf[48];
tnum_strn(tn_buf, sizeof(tn_buf), reg->var_off);
- verbose("misaligned packet access off %d+%s+%d+%d size %d\n",
+ verbose(env,
+ "misaligned packet access off %d+%s+%d+%d size %d\n",
ip_align, tn_buf, reg->off, off, size);
return -EACCES;
}
return 0;
}
-static int check_generic_ptr_alignment(const struct bpf_reg_state *reg,
+static int check_generic_ptr_alignment(struct bpf_verifier_env *env,
+ const struct bpf_reg_state *reg,
const char *pointer_desc,
int off, int size, bool strict)
{
char tn_buf[48];
tnum_strn(tn_buf, sizeof(tn_buf), reg->var_off);
- verbose("misaligned %saccess off %s+%d+%d size %d\n",
+ verbose(env, "misaligned %saccess off %s+%d+%d size %d\n",
pointer_desc, tn_buf, reg->off, off, size);
return -EACCES;
}
switch (reg->type) {
case PTR_TO_PACKET:
- /* special case, because of NET_IP_ALIGN */
- return check_pkt_ptr_alignment(reg, off, size, strict);
+ case PTR_TO_PACKET_META:
+ /* Special case, because of NET_IP_ALIGN. Given metadata sits
+ * right in front, treat it the very same way.
+ */
+ return check_pkt_ptr_alignment(env, reg, off, size, strict);
case PTR_TO_MAP_VALUE:
pointer_desc = "value ";
break;
default:
break;
}
- return check_generic_ptr_alignment(reg, pointer_desc, off, size, strict);
+ return check_generic_ptr_alignment(env, reg, pointer_desc, off, size,
+ strict);
}
/* check whether memory at (regno + off) is accessible for t = (read | write)
int bpf_size, enum bpf_access_type t,
int value_regno)
{
- struct bpf_verifier_state *state = &env->cur_state;
- struct bpf_reg_state *reg = &state->regs[regno];
+ struct bpf_verifier_state *state = env->cur_state;
+ struct bpf_reg_state *regs = cur_regs(env);
+ struct bpf_reg_state *reg = regs + regno;
int size, err = 0;
size = bpf_size_to_bytes(bpf_size);
if (reg->type == PTR_TO_MAP_VALUE) {
if (t == BPF_WRITE && value_regno >= 0 &&
is_pointer_value(env, value_regno)) {
- verbose("R%d leaks addr into map\n", value_regno);
+ verbose(env, "R%d leaks addr into map\n", value_regno);
return -EACCES;
}
err = check_map_access(env, regno, off, size);
if (!err && t == BPF_READ && value_regno >= 0)
- mark_reg_unknown(state->regs, value_regno);
+ mark_reg_unknown(env, regs, value_regno);
} else if (reg->type == PTR_TO_CTX) {
enum bpf_reg_type reg_type = SCALAR_VALUE;
if (t == BPF_WRITE && value_regno >= 0 &&
is_pointer_value(env, value_regno)) {
- verbose("R%d leaks addr into ctx\n", value_regno);
+ verbose(env, "R%d leaks addr into ctx\n", value_regno);
return -EACCES;
}
/* ctx accesses must be at a fixed offset, so that we can
* determine what type of data were returned.
*/
if (reg->off) {
- verbose("dereference of modified ctx ptr R%d off=%d+%d, ctx+const is allowed, ctx+const+const is not\n",
+ verbose(env,
+ "dereference of modified ctx ptr R%d off=%d+%d, ctx+const is allowed, ctx+const+const is not\n",
regno, reg->off, off - reg->off);
return -EACCES;
}
char tn_buf[48];
tnum_strn(tn_buf, sizeof(tn_buf), reg->var_off);
- verbose("variable ctx access var_off=%s off=%d size=%d",
+ verbose(env,
+ "variable ctx access var_off=%s off=%d size=%d",
tn_buf, off, size);
return -EACCES;
}
err = check_ctx_access(env, insn_idx, off, size, t, ®_type);
if (!err && t == BPF_READ && value_regno >= 0) {
/* ctx access returns either a scalar, or a
- * PTR_TO_PACKET[_END]. In the latter case, we know
- * the offset is zero.
+ * PTR_TO_PACKET[_META,_END]. In the latter
+ * case, we know the offset is zero.
*/
if (reg_type == SCALAR_VALUE)
- mark_reg_unknown(state->regs, value_regno);
+ mark_reg_unknown(env, regs, value_regno);
else
- mark_reg_known_zero(state->regs, value_regno);
- state->regs[value_regno].id = 0;
- state->regs[value_regno].off = 0;
- state->regs[value_regno].range = 0;
- state->regs[value_regno].type = reg_type;
+ mark_reg_known_zero(env, regs,
+ value_regno);
+ regs[value_regno].id = 0;
+ regs[value_regno].off = 0;
+ regs[value_regno].range = 0;
+ regs[value_regno].type = reg_type;
}
} else if (reg->type == PTR_TO_STACK) {
char tn_buf[48];
tnum_strn(tn_buf, sizeof(tn_buf), reg->var_off);
- verbose("variable stack access var_off=%s off=%d size=%d",
+ verbose(env, "variable stack access var_off=%s off=%d size=%d",
tn_buf, off, size);
return -EACCES;
}
off += reg->var_off.value;
if (off >= 0 || off < -MAX_BPF_STACK) {
- verbose("invalid stack off=%d size=%d\n", off, size);
+ verbose(env, "invalid stack off=%d size=%d\n", off,
+ size);
return -EACCES;
}
if (env->prog->aux->stack_depth < -off)
env->prog->aux->stack_depth = -off;
- if (t == BPF_WRITE) {
- if (!env->allow_ptr_leaks &&
- state->stack_slot_type[MAX_BPF_STACK + off] == STACK_SPILL &&
- size != BPF_REG_SIZE) {
- verbose("attempt to corrupt spilled pointer on stack\n");
- return -EACCES;
- }
- err = check_stack_write(state, off, size, value_regno);
- } else {
- err = check_stack_read(state, off, size, value_regno);
- }
- } else if (reg->type == PTR_TO_PACKET) {
+ if (t == BPF_WRITE)
+ err = check_stack_write(env, state, off, size,
+ value_regno);
+ else
+ err = check_stack_read(env, state, off, size,
+ value_regno);
+ } else if (reg_is_pkt_pointer(reg)) {
if (t == BPF_WRITE && !may_access_direct_pkt_data(env, NULL, t)) {
- verbose("cannot write into packet\n");
+ verbose(env, "cannot write into packet\n");
return -EACCES;
}
if (t == BPF_WRITE && value_regno >= 0 &&
is_pointer_value(env, value_regno)) {
- verbose("R%d leaks addr into packet\n", value_regno);
+ verbose(env, "R%d leaks addr into packet\n",
+ value_regno);
return -EACCES;
}
err = check_packet_access(env, regno, off, size);
if (!err && t == BPF_READ && value_regno >= 0)
- mark_reg_unknown(state->regs, value_regno);
+ mark_reg_unknown(env, regs, value_regno);
} else {
- verbose("R%d invalid mem access '%s'\n",
- regno, reg_type_str[reg->type]);
+ verbose(env, "R%d invalid mem access '%s'\n", regno,
+ reg_type_str[reg->type]);
return -EACCES;
}
if (!err && size < BPF_REG_SIZE && value_regno >= 0 && t == BPF_READ &&
- state->regs[value_regno].type == SCALAR_VALUE) {
+ regs[value_regno].type == SCALAR_VALUE) {
/* b/h/w load zero-extends, mark upper bits as known 0 */
- state->regs[value_regno].var_off = tnum_cast(
- state->regs[value_regno].var_off, size);
- __update_reg_bounds(&state->regs[value_regno]);
+ regs[value_regno].var_off =
+ tnum_cast(regs[value_regno].var_off, size);
+ __update_reg_bounds(®s[value_regno]);
}
return err;
}
if ((BPF_SIZE(insn->code) != BPF_W && BPF_SIZE(insn->code) != BPF_DW) ||
insn->imm != 0) {
- verbose("BPF_XADD uses reserved fields\n");
+ verbose(env, "BPF_XADD uses reserved fields\n");
return -EINVAL;
}
return err;
if (is_pointer_value(env, insn->src_reg)) {
- verbose("R%d leaks addr into mem\n", insn->src_reg);
+ verbose(env, "R%d leaks addr into mem\n", insn->src_reg);
return -EACCES;
}
int access_size, bool zero_size_allowed,
struct bpf_call_arg_meta *meta)
{
- struct bpf_verifier_state *state = &env->cur_state;
+ struct bpf_verifier_state *state = env->cur_state;
struct bpf_reg_state *regs = state->regs;
- int off, i;
+ int off, i, slot, spi;
if (regs[regno].type != PTR_TO_STACK) {
/* Allow zero-byte read from NULL, regardless of pointer type */
register_is_null(regs[regno]))
return 0;
- verbose("R%d type=%s expected=%s\n", regno,
+ verbose(env, "R%d type=%s expected=%s\n", regno,
reg_type_str[regs[regno].type],
reg_type_str[PTR_TO_STACK]);
return -EACCES;
char tn_buf[48];
tnum_strn(tn_buf, sizeof(tn_buf), regs[regno].var_off);
- verbose("invalid variable stack read R%d var_off=%s\n",
+ verbose(env, "invalid variable stack read R%d var_off=%s\n",
regno, tn_buf);
}
off = regs[regno].off + regs[regno].var_off.value;
if (off >= 0 || off < -MAX_BPF_STACK || off + access_size > 0 ||
access_size <= 0) {
- verbose("invalid stack type R%d off=%d access_size=%d\n",
+ verbose(env, "invalid stack type R%d off=%d access_size=%d\n",
regno, off, access_size);
return -EACCES;
}
}
for (i = 0; i < access_size; i++) {
- if (state->stack_slot_type[MAX_BPF_STACK + off + i] != STACK_MISC) {
- verbose("invalid indirect read from stack off %d+%d size %d\n",
+ slot = -(off + i) - 1;
+ spi = slot / BPF_REG_SIZE;
+ if (state->allocated_stack <= slot ||
+ state->stack[spi].slot_type[slot % BPF_REG_SIZE] !=
+ STACK_MISC) {
+ verbose(env, "invalid indirect read from stack off %d+%d size %d\n",
off, i, access_size);
return -EACCES;
}
int access_size, bool zero_size_allowed,
struct bpf_call_arg_meta *meta)
{
- struct bpf_reg_state *regs = env->cur_state.regs, *reg = ®s[regno];
+ struct bpf_reg_state *regs = cur_regs(env), *reg = ®s[regno];
switch (reg->type) {
case PTR_TO_PACKET:
+ case PTR_TO_PACKET_META:
return check_packet_access(env, regno, reg->off, access_size);
case PTR_TO_MAP_VALUE:
return check_map_access(env, regno, reg->off, access_size);
enum bpf_arg_type arg_type,
struct bpf_call_arg_meta *meta)
{
- struct bpf_reg_state *regs = env->cur_state.regs, *reg = ®s[regno];
+ struct bpf_reg_state *regs = cur_regs(env), *reg = ®s[regno];
enum bpf_reg_type expected_type, type = reg->type;
int err = 0;
if (arg_type == ARG_ANYTHING) {
if (is_pointer_value(env, regno)) {
- verbose("R%d leaks addr into helper function\n", regno);
+ verbose(env, "R%d leaks addr into helper function\n",
+ regno);
return -EACCES;
}
return 0;
}
- if (type == PTR_TO_PACKET &&
+ if (type_is_pkt_pointer(type) &&
!may_access_direct_pkt_data(env, meta, BPF_READ)) {
- verbose("helper access to the packet is not allowed\n");
+ verbose(env, "helper access to the packet is not allowed\n");
return -EACCES;
}
if (arg_type == ARG_PTR_TO_MAP_KEY ||
arg_type == ARG_PTR_TO_MAP_VALUE) {
expected_type = PTR_TO_STACK;
- if (type != PTR_TO_PACKET && type != expected_type)
+ if (!type_is_pkt_pointer(type) &&
+ type != expected_type)
goto err_type;
} else if (arg_type == ARG_CONST_SIZE ||
arg_type == ARG_CONST_SIZE_OR_ZERO) {
*/
if (register_is_null(*reg))
/* final test in check_stack_boundary() */;
- else if (type != PTR_TO_PACKET && type != PTR_TO_MAP_VALUE &&
+ else if (!type_is_pkt_pointer(type) &&
+ type != PTR_TO_MAP_VALUE &&
type != expected_type)
goto err_type;
meta->raw_mode = arg_type == ARG_PTR_TO_UNINIT_MEM;
} else {
- verbose("unsupported arg_type %d\n", arg_type);
+ verbose(env, "unsupported arg_type %d\n", arg_type);
return -EFAULT;
}
* we have to check map_key here. Otherwise it means
* that kernel subsystem misconfigured verifier
*/
- verbose("invalid map_ptr to access map->key\n");
+ verbose(env, "invalid map_ptr to access map->key\n");
return -EACCES;
}
- if (type == PTR_TO_PACKET)
+ if (type_is_pkt_pointer(type))
err = check_packet_access(env, regno, reg->off,
meta->map_ptr->key_size);
else
*/
if (!meta->map_ptr) {
/* kernel subsystem misconfigured verifier */
- verbose("invalid map_ptr to access map->value\n");
+ verbose(env, "invalid map_ptr to access map->value\n");
return -EACCES;
}
- if (type == PTR_TO_PACKET)
+ if (type_is_pkt_pointer(type))
err = check_packet_access(env, regno, reg->off,
meta->map_ptr->value_size);
else
*/
if (regno == 0) {
/* kernel subsystem misconfigured verifier */
- verbose("ARG_CONST_SIZE cannot be first argument\n");
+ verbose(env,
+ "ARG_CONST_SIZE cannot be first argument\n");
return -EACCES;
}
meta = NULL;
if (reg->smin_value < 0) {
- verbose("R%d min value is negative, either use unsigned or 'var &= const'\n",
+ verbose(env, "R%d min value is negative, either use unsigned or 'var &= const'\n",
regno);
return -EACCES;
}
}
if (reg->umax_value >= BPF_MAX_VAR_SIZ) {
- verbose("R%d unbounded memory access, use 'var &= const' or 'if (var < const)'\n",
+ verbose(env, "R%d unbounded memory access, use 'var &= const' or 'if (var < const)'\n",
regno);
return -EACCES;
}
return err;
err_type:
- verbose("R%d type=%s expected=%s\n", regno,
+ verbose(env, "R%d type=%s expected=%s\n", regno,
reg_type_str[type], reg_type_str[expected_type]);
return -EACCES;
}
-static int check_map_func_compatibility(struct bpf_map *map, int func_id)
+static int check_map_func_compatibility(struct bpf_verifier_env *env,
+ struct bpf_map *map, int func_id)
{
if (!map)
return 0;
break;
case BPF_MAP_TYPE_PERF_EVENT_ARRAY:
if (func_id != BPF_FUNC_perf_event_read &&
- func_id != BPF_FUNC_perf_event_output)
+ func_id != BPF_FUNC_perf_event_output &&
+ func_id != BPF_FUNC_perf_event_read_value)
goto error;
break;
case BPF_MAP_TYPE_STACK_TRACE:
if (func_id != BPF_FUNC_redirect_map)
goto error;
break;
+ /* Restrict bpf side of cpumap, open when use-cases appear */
+ case BPF_MAP_TYPE_CPUMAP:
+ if (func_id != BPF_FUNC_redirect_map)
+ goto error;
+ break;
case BPF_MAP_TYPE_ARRAY_OF_MAPS:
case BPF_MAP_TYPE_HASH_OF_MAPS:
if (func_id != BPF_FUNC_map_lookup_elem)
break;
case BPF_FUNC_perf_event_read:
case BPF_FUNC_perf_event_output:
+ case BPF_FUNC_perf_event_read_value:
if (map->map_type != BPF_MAP_TYPE_PERF_EVENT_ARRAY)
goto error;
break;
goto error;
break;
case BPF_FUNC_redirect_map:
- if (map->map_type != BPF_MAP_TYPE_DEVMAP)
+ if (map->map_type != BPF_MAP_TYPE_DEVMAP &&
+ map->map_type != BPF_MAP_TYPE_CPUMAP)
goto error;
break;
case BPF_FUNC_sk_redirect_map:
return 0;
error:
- verbose("cannot pass map_type %d into func %s#%d\n",
+ verbose(env, "cannot pass map_type %d into func %s#%d\n",
map->map_type, func_id_name(func_id), func_id);
return -EINVAL;
}
return count > 1 ? -EINVAL : 0;
}
-/* Packet data might have moved, any old PTR_TO_PACKET[_END] are now invalid,
- * so turn them into unknown SCALAR_VALUE.
+/* Packet data might have moved, any old PTR_TO_PACKET[_META,_END]
+ * are now invalid, so turn them into unknown SCALAR_VALUE.
*/
static void clear_all_pkt_pointers(struct bpf_verifier_env *env)
{
- struct bpf_verifier_state *state = &env->cur_state;
+ struct bpf_verifier_state *state = env->cur_state;
struct bpf_reg_state *regs = state->regs, *reg;
int i;
for (i = 0; i < MAX_BPF_REG; i++)
- if (regs[i].type == PTR_TO_PACKET ||
- regs[i].type == PTR_TO_PACKET_END)
- mark_reg_unknown(regs, i);
+ if (reg_is_pkt_pointer_any(®s[i]))
+ mark_reg_unknown(env, regs, i);
- for (i = 0; i < MAX_BPF_STACK; i += BPF_REG_SIZE) {
- if (state->stack_slot_type[i] != STACK_SPILL)
- continue;
- reg = &state->spilled_regs[i / BPF_REG_SIZE];
- if (reg->type != PTR_TO_PACKET &&
- reg->type != PTR_TO_PACKET_END)
+ for (i = 0; i < state->allocated_stack / BPF_REG_SIZE; i++) {
+ if (state->stack[i].slot_type[0] != STACK_SPILL)
continue;
- __mark_reg_unknown(reg);
+ reg = &state->stack[i].spilled_ptr;
+ if (reg_is_pkt_pointer_any(reg))
+ __mark_reg_unknown(reg);
}
}
static int check_call(struct bpf_verifier_env *env, int func_id, int insn_idx)
{
- struct bpf_verifier_state *state = &env->cur_state;
const struct bpf_func_proto *fn = NULL;
- struct bpf_reg_state *regs = state->regs;
+ struct bpf_reg_state *regs;
struct bpf_call_arg_meta meta;
bool changes_data;
int i, err;
/* find function prototype */
if (func_id < 0 || func_id >= __BPF_FUNC_MAX_ID) {
- verbose("invalid func %s#%d\n", func_id_name(func_id), func_id);
+ verbose(env, "invalid func %s#%d\n", func_id_name(func_id),
+ func_id);
return -EINVAL;
}
- if (env->prog->aux->ops->get_func_proto)
- fn = env->prog->aux->ops->get_func_proto(func_id);
+ if (env->ops->get_func_proto)
+ fn = env->ops->get_func_proto(func_id);
if (!fn) {
- verbose("unknown func %s#%d\n", func_id_name(func_id), func_id);
+ verbose(env, "unknown func %s#%d\n", func_id_name(func_id),
+ func_id);
return -EINVAL;
}
/* eBPF programs must be GPL compatible to use GPL-ed functions */
if (!env->prog->gpl_compatible && fn->gpl_only) {
- verbose("cannot call GPL only function from proprietary program\n");
+ verbose(env, "cannot call GPL only function from proprietary program\n");
return -EINVAL;
}
*/
err = check_raw_mode(fn);
if (err) {
- verbose("kernel subsystem misconfigured func %s#%d\n",
+ verbose(env, "kernel subsystem misconfigured func %s#%d\n",
func_id_name(func_id), func_id);
return err;
}
return err;
}
+ regs = cur_regs(env);
/* reset caller saved regs */
for (i = 0; i < CALLER_SAVED_REGS; i++) {
- mark_reg_not_init(regs, caller_saved[i]);
+ mark_reg_not_init(env, regs, caller_saved[i]);
check_reg_arg(env, caller_saved[i], DST_OP_NO_MARK);
}
/* update return register (already marked as written above) */
if (fn->ret_type == RET_INTEGER) {
/* sets type to SCALAR_VALUE */
- mark_reg_unknown(regs, BPF_REG_0);
+ mark_reg_unknown(env, regs, BPF_REG_0);
} else if (fn->ret_type == RET_VOID) {
regs[BPF_REG_0].type = NOT_INIT;
} else if (fn->ret_type == RET_PTR_TO_MAP_VALUE_OR_NULL) {
regs[BPF_REG_0].type = PTR_TO_MAP_VALUE_OR_NULL;
/* There is no offset yet applied, variable or fixed */
- mark_reg_known_zero(regs, BPF_REG_0);
+ mark_reg_known_zero(env, regs, BPF_REG_0);
regs[BPF_REG_0].off = 0;
/* remember map_ptr, so that check_map_access()
* can check 'value_size' boundary of memory access
* to map element returned from bpf_map_lookup_elem()
*/
if (meta.map_ptr == NULL) {
- verbose("kernel subsystem misconfigured verifier\n");
+ verbose(env,
+ "kernel subsystem misconfigured verifier\n");
return -EINVAL;
}
regs[BPF_REG_0].map_ptr = meta.map_ptr;
else if (insn_aux->map_ptr != meta.map_ptr)
insn_aux->map_ptr = BPF_MAP_PTR_POISON;
} else {
- verbose("unknown return type %d of func %s#%d\n",
+ verbose(env, "unknown return type %d of func %s#%d\n",
fn->ret_type, func_id_name(func_id), func_id);
return -EINVAL;
}
- err = check_map_func_compatibility(meta.map_ptr, func_id);
+ err = check_map_func_compatibility(env, meta.map_ptr, func_id);
if (err)
return err;
const struct bpf_reg_state *ptr_reg,
const struct bpf_reg_state *off_reg)
{
- struct bpf_reg_state *regs = env->cur_state.regs, *dst_reg;
+ struct bpf_reg_state *regs = cur_regs(env), *dst_reg;
bool known = tnum_is_const(off_reg->var_off);
s64 smin_val = off_reg->smin_value, smax_val = off_reg->smax_value,
smin_ptr = ptr_reg->smin_value, smax_ptr = ptr_reg->smax_value;
dst_reg = ®s[dst];
if (WARN_ON_ONCE(known && (smin_val != smax_val))) {
- print_verifier_state(&env->cur_state);
- verbose("verifier internal error: known but bad sbounds\n");
+ print_verifier_state(env, env->cur_state);
+ verbose(env,
+ "verifier internal error: known but bad sbounds\n");
return -EINVAL;
}
if (WARN_ON_ONCE(known && (umin_val != umax_val))) {
- print_verifier_state(&env->cur_state);
- verbose("verifier internal error: known but bad ubounds\n");
+ print_verifier_state(env, env->cur_state);
+ verbose(env,
+ "verifier internal error: known but bad ubounds\n");
return -EINVAL;
}
if (BPF_CLASS(insn->code) != BPF_ALU64) {
/* 32-bit ALU ops on pointers produce (meaningless) scalars */
if (!env->allow_ptr_leaks)
- verbose("R%d 32-bit pointer arithmetic prohibited\n",
+ verbose(env,
+ "R%d 32-bit pointer arithmetic prohibited\n",
dst);
return -EACCES;
}
if (ptr_reg->type == PTR_TO_MAP_VALUE_OR_NULL) {
if (!env->allow_ptr_leaks)
- verbose("R%d pointer arithmetic on PTR_TO_MAP_VALUE_OR_NULL prohibited, null-check it first\n",
+ verbose(env, "R%d pointer arithmetic on PTR_TO_MAP_VALUE_OR_NULL prohibited, null-check it first\n",
dst);
return -EACCES;
}
if (ptr_reg->type == CONST_PTR_TO_MAP) {
if (!env->allow_ptr_leaks)
- verbose("R%d pointer arithmetic on CONST_PTR_TO_MAP prohibited\n",
+ verbose(env, "R%d pointer arithmetic on CONST_PTR_TO_MAP prohibited\n",
dst);
return -EACCES;
}
if (ptr_reg->type == PTR_TO_PACKET_END) {
if (!env->allow_ptr_leaks)
- verbose("R%d pointer arithmetic on PTR_TO_PACKET_END prohibited\n",
+ verbose(env, "R%d pointer arithmetic on PTR_TO_PACKET_END prohibited\n",
dst);
return -EACCES;
}
}
dst_reg->var_off = tnum_add(ptr_reg->var_off, off_reg->var_off);
dst_reg->off = ptr_reg->off;
- if (ptr_reg->type == PTR_TO_PACKET) {
+ if (reg_is_pkt_pointer(ptr_reg)) {
dst_reg->id = ++env->id_gen;
/* something was added to pkt_ptr, set range to zero */
dst_reg->range = 0;
if (dst_reg == off_reg) {
/* scalar -= pointer. Creates an unknown scalar */
if (!env->allow_ptr_leaks)
- verbose("R%d tried to subtract pointer from scalar\n",
+ verbose(env, "R%d tried to subtract pointer from scalar\n",
dst);
return -EACCES;
}
*/
if (ptr_reg->type == PTR_TO_STACK) {
if (!env->allow_ptr_leaks)
- verbose("R%d subtraction from stack pointer prohibited\n",
+ verbose(env, "R%d subtraction from stack pointer prohibited\n",
dst);
return -EACCES;
}
}
dst_reg->var_off = tnum_sub(ptr_reg->var_off, off_reg->var_off);
dst_reg->off = ptr_reg->off;
- if (ptr_reg->type == PTR_TO_PACKET) {
+ if (reg_is_pkt_pointer(ptr_reg)) {
dst_reg->id = ++env->id_gen;
/* something was added to pkt_ptr, set range to zero */
if (smin_val < 0)
* ptr &= ~3 which would reduce min_value by 3.)
*/
if (!env->allow_ptr_leaks)
- verbose("R%d bitwise operator %s on pointer prohibited\n",
+ verbose(env, "R%d bitwise operator %s on pointer prohibited\n",
dst, bpf_alu_string[opcode >> 4]);
return -EACCES;
default:
/* other operators (e.g. MUL,LSH) produce non-pointer results */
if (!env->allow_ptr_leaks)
- verbose("R%d pointer arithmetic with %s operator prohibited\n",
+ verbose(env, "R%d pointer arithmetic with %s operator prohibited\n",
dst, bpf_alu_string[opcode >> 4]);
return -EACCES;
}
struct bpf_reg_state *dst_reg,
struct bpf_reg_state src_reg)
{
- struct bpf_reg_state *regs = env->cur_state.regs;
+ struct bpf_reg_state *regs = cur_regs(env);
u8 opcode = BPF_OP(insn->code);
bool src_known, dst_known;
s64 smin_val, smax_val;
/* Shifts greater than 63 are undefined. This includes
* shifts by a negative number.
*/
- mark_reg_unknown(regs, insn->dst_reg);
+ mark_reg_unknown(env, regs, insn->dst_reg);
break;
}
/* We lose all sign bit information (except what we can pick
/* Shifts greater than 63 are undefined. This includes
* shifts by a negative number.
*/
- mark_reg_unknown(regs, insn->dst_reg);
+ mark_reg_unknown(env, regs, insn->dst_reg);
break;
}
/* BPF_RSH is an unsigned shift, so make the appropriate casts */
__update_reg_bounds(dst_reg);
break;
default:
- mark_reg_unknown(regs, insn->dst_reg);
+ mark_reg_unknown(env, regs, insn->dst_reg);
break;
}
static int adjust_reg_min_max_vals(struct bpf_verifier_env *env,
struct bpf_insn *insn)
{
- struct bpf_reg_state *regs = env->cur_state.regs, *dst_reg, *src_reg;
+ struct bpf_reg_state *regs = cur_regs(env), *dst_reg, *src_reg;
struct bpf_reg_state *ptr_reg = NULL, off_reg = {0};
u8 opcode = BPF_OP(insn->code);
int rc;
* an arbitrary scalar.
*/
if (!env->allow_ptr_leaks) {
- verbose("R%d pointer %s pointer prohibited\n",
+ verbose(env, "R%d pointer %s pointer prohibited\n",
insn->dst_reg,
bpf_alu_string[opcode >> 4]);
return -EACCES;
}
- mark_reg_unknown(regs, insn->dst_reg);
+ mark_reg_unknown(env, regs, insn->dst_reg);
return 0;
} else {
/* scalar += pointer
/* Got here implies adding two SCALAR_VALUEs */
if (WARN_ON_ONCE(ptr_reg)) {
- print_verifier_state(&env->cur_state);
- verbose("verifier internal error: unexpected ptr_reg\n");
+ print_verifier_state(env, env->cur_state);
+ verbose(env, "verifier internal error: unexpected ptr_reg\n");
return -EINVAL;
}
if (WARN_ON(!src_reg)) {
- print_verifier_state(&env->cur_state);
- verbose("verifier internal error: no src_reg\n");
+ print_verifier_state(env, env->cur_state);
+ verbose(env, "verifier internal error: no src_reg\n");
return -EINVAL;
}
return adjust_scalar_min_max_vals(env, insn, dst_reg, *src_reg);
/* check validity of 32-bit and 64-bit arithmetic operations */
static int check_alu_op(struct bpf_verifier_env *env, struct bpf_insn *insn)
{
- struct bpf_reg_state *regs = env->cur_state.regs;
+ struct bpf_reg_state *regs = cur_regs(env);
u8 opcode = BPF_OP(insn->code);
int err;
if (BPF_SRC(insn->code) != 0 ||
insn->src_reg != BPF_REG_0 ||
insn->off != 0 || insn->imm != 0) {
- verbose("BPF_NEG uses reserved fields\n");
+ verbose(env, "BPF_NEG uses reserved fields\n");
return -EINVAL;
}
} else {
if (insn->src_reg != BPF_REG_0 || insn->off != 0 ||
(insn->imm != 16 && insn->imm != 32 && insn->imm != 64) ||
BPF_CLASS(insn->code) == BPF_ALU64) {
- verbose("BPF_END uses reserved fields\n");
+ verbose(env, "BPF_END uses reserved fields\n");
return -EINVAL;
}
}
return err;
if (is_pointer_value(env, insn->dst_reg)) {
- verbose("R%d pointer arithmetic prohibited\n",
+ verbose(env, "R%d pointer arithmetic prohibited\n",
insn->dst_reg);
return -EACCES;
}
if (BPF_SRC(insn->code) == BPF_X) {
if (insn->imm != 0 || insn->off != 0) {
- verbose("BPF_MOV uses reserved fields\n");
+ verbose(env, "BPF_MOV uses reserved fields\n");
return -EINVAL;
}
return err;
} else {
if (insn->src_reg != BPF_REG_0 || insn->off != 0) {
- verbose("BPF_MOV uses reserved fields\n");
+ verbose(env, "BPF_MOV uses reserved fields\n");
return -EINVAL;
}
}
} else {
/* R1 = (u32) R2 */
if (is_pointer_value(env, insn->src_reg)) {
- verbose("R%d partial copy of pointer\n",
+ verbose(env,
+ "R%d partial copy of pointer\n",
insn->src_reg);
return -EACCES;
}
- mark_reg_unknown(regs, insn->dst_reg);
+ mark_reg_unknown(env, regs, insn->dst_reg);
/* high 32 bits are known zero. */
regs[insn->dst_reg].var_off = tnum_cast(
regs[insn->dst_reg].var_off, 4);
}
} else if (opcode > BPF_END) {
- verbose("invalid BPF_ALU opcode %x\n", opcode);
+ verbose(env, "invalid BPF_ALU opcode %x\n", opcode);
return -EINVAL;
} else { /* all other ALU ops: and, sub, xor, add, ... */
if (BPF_SRC(insn->code) == BPF_X) {
if (insn->imm != 0 || insn->off != 0) {
- verbose("BPF_ALU uses reserved fields\n");
+ verbose(env, "BPF_ALU uses reserved fields\n");
return -EINVAL;
}
/* check src1 operand */
return err;
} else {
if (insn->src_reg != BPF_REG_0 || insn->off != 0) {
- verbose("BPF_ALU uses reserved fields\n");
+ verbose(env, "BPF_ALU uses reserved fields\n");
return -EINVAL;
}
}
if ((opcode == BPF_MOD || opcode == BPF_DIV) &&
BPF_SRC(insn->code) == BPF_K && insn->imm == 0) {
- verbose("div by zero\n");
+ verbose(env, "div by zero\n");
return -EINVAL;
}
int size = BPF_CLASS(insn->code) == BPF_ALU64 ? 64 : 32;
if (insn->imm < 0 || insn->imm >= size) {
- verbose("invalid shift %d\n", insn->imm);
+ verbose(env, "invalid shift %d\n", insn->imm);
return -EINVAL;
}
}
static void find_good_pkt_pointers(struct bpf_verifier_state *state,
struct bpf_reg_state *dst_reg,
+ enum bpf_reg_type type,
bool range_right_open)
{
struct bpf_reg_state *regs = state->regs, *reg;
* dst_reg->off is known < MAX_PACKET_OFF, therefore it fits in a u16.
*/
for (i = 0; i < MAX_BPF_REG; i++)
- if (regs[i].type == PTR_TO_PACKET && regs[i].id == dst_reg->id)
+ if (regs[i].type == type && regs[i].id == dst_reg->id)
/* keep the maximum range already checked */
regs[i].range = max(regs[i].range, new_range);
- for (i = 0; i < MAX_BPF_STACK; i += BPF_REG_SIZE) {
- if (state->stack_slot_type[i] != STACK_SPILL)
+ for (i = 0; i < state->allocated_stack / BPF_REG_SIZE; i++) {
+ if (state->stack[i].slot_type[0] != STACK_SPILL)
continue;
- reg = &state->spilled_regs[i / BPF_REG_SIZE];
- if (reg->type == PTR_TO_PACKET && reg->id == dst_reg->id)
+ reg = &state->stack[i].spilled_ptr;
+ if (reg->type == type && reg->id == dst_reg->id)
reg->range = max(reg->range, new_range);
}
}
for (i = 0; i < MAX_BPF_REG; i++)
mark_map_reg(regs, i, id, is_null);
- for (i = 0; i < MAX_BPF_STACK; i += BPF_REG_SIZE) {
- if (state->stack_slot_type[i] != STACK_SPILL)
+ for (i = 0; i < state->allocated_stack / BPF_REG_SIZE; i++) {
+ if (state->stack[i].slot_type[0] != STACK_SPILL)
continue;
- mark_map_reg(state->spilled_regs, i / BPF_REG_SIZE, id, is_null);
+ mark_map_reg(&state->stack[i].spilled_ptr, 0, id, is_null);
}
}
+static bool try_match_pkt_pointers(const struct bpf_insn *insn,
+ struct bpf_reg_state *dst_reg,
+ struct bpf_reg_state *src_reg,
+ struct bpf_verifier_state *this_branch,
+ struct bpf_verifier_state *other_branch)
+{
+ if (BPF_SRC(insn->code) != BPF_X)
+ return false;
+
+ switch (BPF_OP(insn->code)) {
+ case BPF_JGT:
+ if ((dst_reg->type == PTR_TO_PACKET &&
+ src_reg->type == PTR_TO_PACKET_END) ||
+ (dst_reg->type == PTR_TO_PACKET_META &&
+ reg_is_init_pkt_pointer(src_reg, PTR_TO_PACKET))) {
+ /* pkt_data' > pkt_end, pkt_meta' > pkt_data */
+ find_good_pkt_pointers(this_branch, dst_reg,
+ dst_reg->type, false);
+ } else if ((dst_reg->type == PTR_TO_PACKET_END &&
+ src_reg->type == PTR_TO_PACKET) ||
+ (reg_is_init_pkt_pointer(dst_reg, PTR_TO_PACKET) &&
+ src_reg->type == PTR_TO_PACKET_META)) {
+ /* pkt_end > pkt_data', pkt_data > pkt_meta' */
+ find_good_pkt_pointers(other_branch, src_reg,
+ src_reg->type, true);
+ } else {
+ return false;
+ }
+ break;
+ case BPF_JLT:
+ if ((dst_reg->type == PTR_TO_PACKET &&
+ src_reg->type == PTR_TO_PACKET_END) ||
+ (dst_reg->type == PTR_TO_PACKET_META &&
+ reg_is_init_pkt_pointer(src_reg, PTR_TO_PACKET))) {
+ /* pkt_data' < pkt_end, pkt_meta' < pkt_data */
+ find_good_pkt_pointers(other_branch, dst_reg,
+ dst_reg->type, true);
+ } else if ((dst_reg->type == PTR_TO_PACKET_END &&
+ src_reg->type == PTR_TO_PACKET) ||
+ (reg_is_init_pkt_pointer(dst_reg, PTR_TO_PACKET) &&
+ src_reg->type == PTR_TO_PACKET_META)) {
+ /* pkt_end < pkt_data', pkt_data > pkt_meta' */
+ find_good_pkt_pointers(this_branch, src_reg,
+ src_reg->type, false);
+ } else {
+ return false;
+ }
+ break;
+ case BPF_JGE:
+ if ((dst_reg->type == PTR_TO_PACKET &&
+ src_reg->type == PTR_TO_PACKET_END) ||
+ (dst_reg->type == PTR_TO_PACKET_META &&
+ reg_is_init_pkt_pointer(src_reg, PTR_TO_PACKET))) {
+ /* pkt_data' >= pkt_end, pkt_meta' >= pkt_data */
+ find_good_pkt_pointers(this_branch, dst_reg,
+ dst_reg->type, true);
+ } else if ((dst_reg->type == PTR_TO_PACKET_END &&
+ src_reg->type == PTR_TO_PACKET) ||
+ (reg_is_init_pkt_pointer(dst_reg, PTR_TO_PACKET) &&
+ src_reg->type == PTR_TO_PACKET_META)) {
+ /* pkt_end >= pkt_data', pkt_data >= pkt_meta' */
+ find_good_pkt_pointers(other_branch, src_reg,
+ src_reg->type, false);
+ } else {
+ return false;
+ }
+ break;
+ case BPF_JLE:
+ if ((dst_reg->type == PTR_TO_PACKET &&
+ src_reg->type == PTR_TO_PACKET_END) ||
+ (dst_reg->type == PTR_TO_PACKET_META &&
+ reg_is_init_pkt_pointer(src_reg, PTR_TO_PACKET))) {
+ /* pkt_data' <= pkt_end, pkt_meta' <= pkt_data */
+ find_good_pkt_pointers(other_branch, dst_reg,
+ dst_reg->type, false);
+ } else if ((dst_reg->type == PTR_TO_PACKET_END &&
+ src_reg->type == PTR_TO_PACKET) ||
+ (reg_is_init_pkt_pointer(dst_reg, PTR_TO_PACKET) &&
+ src_reg->type == PTR_TO_PACKET_META)) {
+ /* pkt_end <= pkt_data', pkt_data <= pkt_meta' */
+ find_good_pkt_pointers(this_branch, src_reg,
+ src_reg->type, true);
+ } else {
+ return false;
+ }
+ break;
+ default:
+ return false;
+ }
+
+ return true;
+}
+
static int check_cond_jmp_op(struct bpf_verifier_env *env,
struct bpf_insn *insn, int *insn_idx)
{
- struct bpf_verifier_state *other_branch, *this_branch = &env->cur_state;
+ struct bpf_verifier_state *other_branch, *this_branch = env->cur_state;
struct bpf_reg_state *regs = this_branch->regs, *dst_reg;
u8 opcode = BPF_OP(insn->code);
int err;
if (opcode > BPF_JSLE) {
- verbose("invalid BPF_JMP opcode %x\n", opcode);
+ verbose(env, "invalid BPF_JMP opcode %x\n", opcode);
return -EINVAL;
}
if (BPF_SRC(insn->code) == BPF_X) {
if (insn->imm != 0) {
- verbose("BPF_JMP uses reserved fields\n");
+ verbose(env, "BPF_JMP uses reserved fields\n");
return -EINVAL;
}
return err;
if (is_pointer_value(env, insn->src_reg)) {
- verbose("R%d pointer comparison prohibited\n",
+ verbose(env, "R%d pointer comparison prohibited\n",
insn->src_reg);
return -EACCES;
}
} else {
if (insn->src_reg != BPF_REG_0) {
- verbose("BPF_JMP uses reserved fields\n");
+ verbose(env, "BPF_JMP uses reserved fields\n");
return -EINVAL;
}
}
*/
mark_map_regs(this_branch, insn->dst_reg, opcode == BPF_JNE);
mark_map_regs(other_branch, insn->dst_reg, opcode == BPF_JEQ);
- } else if (BPF_SRC(insn->code) == BPF_X && opcode == BPF_JGT &&
- dst_reg->type == PTR_TO_PACKET &&
- regs[insn->src_reg].type == PTR_TO_PACKET_END) {
- /* pkt_data' > pkt_end */
- find_good_pkt_pointers(this_branch, dst_reg, false);
- } else if (BPF_SRC(insn->code) == BPF_X && opcode == BPF_JGT &&
- dst_reg->type == PTR_TO_PACKET_END &&
- regs[insn->src_reg].type == PTR_TO_PACKET) {
- /* pkt_end > pkt_data' */
- find_good_pkt_pointers(other_branch, ®s[insn->src_reg], true);
- } else if (BPF_SRC(insn->code) == BPF_X && opcode == BPF_JLT &&
- dst_reg->type == PTR_TO_PACKET &&
- regs[insn->src_reg].type == PTR_TO_PACKET_END) {
- /* pkt_data' < pkt_end */
- find_good_pkt_pointers(other_branch, dst_reg, true);
- } else if (BPF_SRC(insn->code) == BPF_X && opcode == BPF_JLT &&
- dst_reg->type == PTR_TO_PACKET_END &&
- regs[insn->src_reg].type == PTR_TO_PACKET) {
- /* pkt_end < pkt_data' */
- find_good_pkt_pointers(this_branch, ®s[insn->src_reg], false);
- } else if (BPF_SRC(insn->code) == BPF_X && opcode == BPF_JGE &&
- dst_reg->type == PTR_TO_PACKET &&
- regs[insn->src_reg].type == PTR_TO_PACKET_END) {
- /* pkt_data' >= pkt_end */
- find_good_pkt_pointers(this_branch, dst_reg, true);
- } else if (BPF_SRC(insn->code) == BPF_X && opcode == BPF_JGE &&
- dst_reg->type == PTR_TO_PACKET_END &&
- regs[insn->src_reg].type == PTR_TO_PACKET) {
- /* pkt_end >= pkt_data' */
- find_good_pkt_pointers(other_branch, ®s[insn->src_reg], false);
- } else if (BPF_SRC(insn->code) == BPF_X && opcode == BPF_JLE &&
- dst_reg->type == PTR_TO_PACKET &&
- regs[insn->src_reg].type == PTR_TO_PACKET_END) {
- /* pkt_data' <= pkt_end */
- find_good_pkt_pointers(other_branch, dst_reg, false);
- } else if (BPF_SRC(insn->code) == BPF_X && opcode == BPF_JLE &&
- dst_reg->type == PTR_TO_PACKET_END &&
- regs[insn->src_reg].type == PTR_TO_PACKET) {
- /* pkt_end <= pkt_data' */
- find_good_pkt_pointers(this_branch, ®s[insn->src_reg], true);
- } else if (is_pointer_value(env, insn->dst_reg)) {
- verbose("R%d pointer comparison prohibited\n", insn->dst_reg);
+ } else if (!try_match_pkt_pointers(insn, dst_reg, ®s[insn->src_reg],
+ this_branch, other_branch) &&
+ is_pointer_value(env, insn->dst_reg)) {
+ verbose(env, "R%d pointer comparison prohibited\n",
+ insn->dst_reg);
return -EACCES;
}
- if (log_level)
- print_verifier_state(this_branch);
+ if (env->log.level)
+ print_verifier_state(env, this_branch);
return 0;
}
/* verify BPF_LD_IMM64 instruction */
static int check_ld_imm(struct bpf_verifier_env *env, struct bpf_insn *insn)
{
- struct bpf_reg_state *regs = env->cur_state.regs;
+ struct bpf_reg_state *regs = cur_regs(env);
int err;
if (BPF_SIZE(insn->code) != BPF_DW) {
- verbose("invalid BPF_LD_IMM insn\n");
+ verbose(env, "invalid BPF_LD_IMM insn\n");
return -EINVAL;
}
if (insn->off != 0) {
- verbose("BPF_LD_IMM64 uses reserved fields\n");
+ verbose(env, "BPF_LD_IMM64 uses reserved fields\n");
return -EINVAL;
}
*/
static int check_ld_abs(struct bpf_verifier_env *env, struct bpf_insn *insn)
{
- struct bpf_reg_state *regs = env->cur_state.regs;
+ struct bpf_reg_state *regs = cur_regs(env);
u8 mode = BPF_MODE(insn->code);
int i, err;
if (!may_access_skb(env->prog->type)) {
- verbose("BPF_LD_[ABS|IND] instructions not allowed for this program type\n");
+ verbose(env, "BPF_LD_[ABS|IND] instructions not allowed for this program type\n");
return -EINVAL;
}
if (insn->dst_reg != BPF_REG_0 || insn->off != 0 ||
BPF_SIZE(insn->code) == BPF_DW ||
(mode == BPF_ABS && insn->src_reg != BPF_REG_0)) {
- verbose("BPF_LD_[ABS|IND] uses reserved fields\n");
+ verbose(env, "BPF_LD_[ABS|IND] uses reserved fields\n");
return -EINVAL;
}
return err;
if (regs[BPF_REG_6].type != PTR_TO_CTX) {
- verbose("at the time of BPF_LD_ABS|IND R6 != pointer to skb\n");
+ verbose(env,
+ "at the time of BPF_LD_ABS|IND R6 != pointer to skb\n");
return -EINVAL;
}
/* reset caller saved regs to unreadable */
for (i = 0; i < CALLER_SAVED_REGS; i++) {
- mark_reg_not_init(regs, caller_saved[i]);
+ mark_reg_not_init(env, regs, caller_saved[i]);
check_reg_arg(env, caller_saved[i], DST_OP_NO_MARK);
}
* the value fetched from the packet.
* Already marked as written above.
*/
- mark_reg_unknown(regs, BPF_REG_0);
+ mark_reg_unknown(env, regs, BPF_REG_0);
+ return 0;
+}
+
+static int check_return_code(struct bpf_verifier_env *env)
+{
+ struct bpf_reg_state *reg;
+ struct tnum range = tnum_range(0, 1);
+
+ switch (env->prog->type) {
+ case BPF_PROG_TYPE_CGROUP_SKB:
+ case BPF_PROG_TYPE_CGROUP_SOCK:
+ case BPF_PROG_TYPE_SOCK_OPS:
+ break;
+ default:
+ return 0;
+ }
+
+ reg = cur_regs(env) + BPF_REG_0;
+ if (reg->type != SCALAR_VALUE) {
+ verbose(env, "At program exit the register R0 is not a known value (%s)\n",
+ reg_type_str[reg->type]);
+ return -EINVAL;
+ }
+
+ if (!tnum_in(range, reg->var_off)) {
+ verbose(env, "At program exit the register R0 ");
+ if (!tnum_is_unknown(reg->var_off)) {
+ char tn_buf[48];
+
+ tnum_strn(tn_buf, sizeof(tn_buf), reg->var_off);
+ verbose(env, "has value %s", tn_buf);
+ } else {
+ verbose(env, "has unknown scalar value");
+ }
+ verbose(env, " should have been 0 or 1\n");
+ return -EINVAL;
+ }
return 0;
}
return 0;
if (w < 0 || w >= env->prog->len) {
- verbose("jump out of range from insn %d to %d\n", t, w);
+ verbose(env, "jump out of range from insn %d to %d\n", t, w);
return -EINVAL;
}
insn_stack[cur_stack++] = w;
return 1;
} else if ((insn_state[w] & 0xF0) == DISCOVERED) {
- verbose("back-edge from insn %d to %d\n", t, w);
+ verbose(env, "back-edge from insn %d to %d\n", t, w);
return -EINVAL;
} else if (insn_state[w] == EXPLORED) {
/* forward- or cross-edge */
insn_state[t] = DISCOVERED | e;
} else {
- verbose("insn state internal bug\n");
+ verbose(env, "insn state internal bug\n");
return -EFAULT;
}
return 0;
mark_explored:
insn_state[t] = EXPLORED;
if (cur_stack-- <= 0) {
- verbose("pop stack internal bug\n");
+ verbose(env, "pop stack internal bug\n");
ret = -EFAULT;
goto err_free;
}
check_state:
for (i = 0; i < insn_cnt; i++) {
if (insn_state[i] != EXPLORED) {
- verbose("unreachable insn %d\n", i);
+ verbose(env, "unreachable insn %d\n", i);
ret = -EINVAL;
goto err_free;
}
return false;
/* Check our ids match any regs they're supposed to */
return check_ids(rold->id, rcur->id, idmap);
+ case PTR_TO_PACKET_META:
case PTR_TO_PACKET:
- if (rcur->type != PTR_TO_PACKET)
+ if (rcur->type != rold->type)
return false;
/* We must have at least as much range as the old ptr
* did, so that any accesses which were safe before are
return false;
}
+static bool stacksafe(struct bpf_verifier_state *old,
+ struct bpf_verifier_state *cur,
+ struct idpair *idmap)
+{
+ int i, spi;
+
+ /* if explored stack has more populated slots than current stack
+ * such stacks are not equivalent
+ */
+ if (old->allocated_stack > cur->allocated_stack)
+ return false;
+
+ /* walk slots of the explored stack and ignore any additional
+ * slots in the current stack, since explored(safe) state
+ * didn't use them
+ */
+ for (i = 0; i < old->allocated_stack; i++) {
+ spi = i / BPF_REG_SIZE;
+
+ if (old->stack[spi].slot_type[i % BPF_REG_SIZE] == STACK_INVALID)
+ continue;
+ if (old->stack[spi].slot_type[i % BPF_REG_SIZE] !=
+ cur->stack[spi].slot_type[i % BPF_REG_SIZE])
+ /* Ex: old explored (safe) state has STACK_SPILL in
+ * this stack slot, but current has has STACK_MISC ->
+ * this verifier states are not equivalent,
+ * return false to continue verification of this path
+ */
+ return false;
+ if (i % BPF_REG_SIZE)
+ continue;
+ if (old->stack[spi].slot_type[0] != STACK_SPILL)
+ continue;
+ if (!regsafe(&old->stack[spi].spilled_ptr,
+ &cur->stack[spi].spilled_ptr,
+ idmap))
+ /* when explored and current stack slot are both storing
+ * spilled registers, check that stored pointers types
+ * are the same as well.
+ * Ex: explored safe path could have stored
+ * (bpf_reg_state) {.type = PTR_TO_STACK, .off = -8}
+ * but current path has stored:
+ * (bpf_reg_state) {.type = PTR_TO_STACK, .off = -16}
+ * such verifier states are not equivalent.
+ * return false to continue verification of this path
+ */
+ return false;
+ }
+ return true;
+}
+
/* compare two verifier states
*
* all states stored in state_list are known to be valid, since
goto out_free;
}
- for (i = 0; i < MAX_BPF_STACK; i++) {
- if (old->stack_slot_type[i] == STACK_INVALID)
- continue;
- if (old->stack_slot_type[i] != cur->stack_slot_type[i])
- /* Ex: old explored (safe) state has STACK_SPILL in
- * this stack slot, but current has has STACK_MISC ->
- * this verifier states are not equivalent,
- * return false to continue verification of this path
- */
- goto out_free;
- if (i % BPF_REG_SIZE)
- continue;
- if (old->stack_slot_type[i] != STACK_SPILL)
- continue;
- if (!regsafe(&old->spilled_regs[i / BPF_REG_SIZE],
- &cur->spilled_regs[i / BPF_REG_SIZE],
- idmap))
- /* when explored and current stack slot are both storing
- * spilled registers, check that stored pointers types
- * are the same as well.
- * Ex: explored safe path could have stored
- * (bpf_reg_state) {.type = PTR_TO_STACK, .off = -8}
- * but current path has stored:
- * (bpf_reg_state) {.type = PTR_TO_STACK, .off = -16}
- * such verifier states are not equivalent.
- * return false to continue verification of this path
- */
- goto out_free;
- else
- continue;
- }
+ if (!stacksafe(old, cur, idmap))
+ goto out_free;
ret = true;
out_free:
kfree(idmap);
}
}
/* ... and stack slots */
- for (i = 0; i < MAX_BPF_STACK / BPF_REG_SIZE; i++) {
- if (parent->stack_slot_type[i * BPF_REG_SIZE] != STACK_SPILL)
+ for (i = 0; i < state->allocated_stack / BPF_REG_SIZE &&
+ i < parent->allocated_stack / BPF_REG_SIZE; i++) {
+ if (parent->stack[i].slot_type[0] != STACK_SPILL)
continue;
- if (state->stack_slot_type[i * BPF_REG_SIZE] != STACK_SPILL)
+ if (state->stack[i].slot_type[0] != STACK_SPILL)
continue;
- if (parent->spilled_regs[i].live & REG_LIVE_READ)
+ if (parent->stack[i].spilled_ptr.live & REG_LIVE_READ)
continue;
- if (writes && (state->spilled_regs[i].live & REG_LIVE_WRITTEN))
+ if (writes &&
+ (state->stack[i].spilled_ptr.live & REG_LIVE_WRITTEN))
continue;
- if (state->spilled_regs[i].live & REG_LIVE_READ) {
- parent->spilled_regs[i].live |= REG_LIVE_READ;
+ if (state->stack[i].spilled_ptr.live & REG_LIVE_READ) {
+ parent->stack[i].spilled_ptr.live |= REG_LIVE_READ;
touched = true;
}
}
{
struct bpf_verifier_state_list *new_sl;
struct bpf_verifier_state_list *sl;
- int i;
+ struct bpf_verifier_state *cur = env->cur_state;
+ int i, err;
sl = env->explored_states[insn_idx];
if (!sl)
return 0;
while (sl != STATE_LIST_MARK) {
- if (states_equal(env, &sl->state, &env->cur_state)) {
+ if (states_equal(env, &sl->state, cur)) {
/* reached equivalent register/stack state,
* prune the search.
* Registers read by the continuation are read by us.
* they'll be immediately forgotten as we're pruning
* this state and will pop a new one.
*/
- propagate_liveness(&sl->state, &env->cur_state);
+ propagate_liveness(&sl->state, cur);
return 1;
}
sl = sl->next;
* it will be rejected. Since there are no loops, we won't be
* seeing this 'insn_idx' instruction again on the way to bpf_exit
*/
- new_sl = kmalloc(sizeof(struct bpf_verifier_state_list), GFP_USER);
+ new_sl = kzalloc(sizeof(struct bpf_verifier_state_list), GFP_KERNEL);
if (!new_sl)
return -ENOMEM;
/* add new state to the head of linked list */
- memcpy(&new_sl->state, &env->cur_state, sizeof(env->cur_state));
+ err = copy_verifier_state(&new_sl->state, cur);
+ if (err) {
+ free_verifier_state(&new_sl->state, false);
+ kfree(new_sl);
+ return err;
+ }
new_sl->next = env->explored_states[insn_idx];
env->explored_states[insn_idx] = new_sl;
/* connect new state to parentage chain */
- env->cur_state.parent = &new_sl->state;
+ cur->parent = &new_sl->state;
/* clear write marks in current state: the writes we did are not writes
* our child did, so they don't screen off its reads from us.
* (There are no read marks in current state, because reads always mark
* explored_states can get read marks.)
*/
for (i = 0; i < BPF_REG_FP; i++)
- env->cur_state.regs[i].live = REG_LIVE_NONE;
- for (i = 0; i < MAX_BPF_STACK / BPF_REG_SIZE; i++)
- if (env->cur_state.stack_slot_type[i * BPF_REG_SIZE] == STACK_SPILL)
- env->cur_state.spilled_regs[i].live = REG_LIVE_NONE;
+ cur->regs[i].live = REG_LIVE_NONE;
+ for (i = 0; i < cur->allocated_stack / BPF_REG_SIZE; i++)
+ if (cur->stack[i].slot_type[0] == STACK_SPILL)
+ cur->stack[i].spilled_ptr.live = REG_LIVE_NONE;
return 0;
}
static int do_check(struct bpf_verifier_env *env)
{
- struct bpf_verifier_state *state = &env->cur_state;
+ struct bpf_verifier_state *state;
struct bpf_insn *insns = env->prog->insnsi;
- struct bpf_reg_state *regs = state->regs;
+ struct bpf_reg_state *regs;
int insn_cnt = env->prog->len;
int insn_idx, prev_insn_idx = 0;
int insn_processed = 0;
bool do_print_state = false;
- init_reg_state(regs);
+ state = kzalloc(sizeof(struct bpf_verifier_state), GFP_KERNEL);
+ if (!state)
+ return -ENOMEM;
+ env->cur_state = state;
+ init_reg_state(env, state->regs);
state->parent = NULL;
insn_idx = 0;
for (;;) {
int err;
if (insn_idx >= insn_cnt) {
- verbose("invalid insn idx %d insn_cnt %d\n",
+ verbose(env, "invalid insn idx %d insn_cnt %d\n",
insn_idx, insn_cnt);
return -EFAULT;
}
class = BPF_CLASS(insn->code);
if (++insn_processed > BPF_COMPLEXITY_LIMIT_INSNS) {
- verbose("BPF program is too large. Processed %d insn\n",
+ verbose(env,
+ "BPF program is too large. Processed %d insn\n",
insn_processed);
return -E2BIG;
}
return err;
if (err == 1) {
/* found equivalent state, can prune the search */
- if (log_level) {
+ if (env->log.level) {
if (do_print_state)
- verbose("\nfrom %d to %d: safe\n",
+ verbose(env, "\nfrom %d to %d: safe\n",
prev_insn_idx, insn_idx);
else
- verbose("%d: safe\n", insn_idx);
+ verbose(env, "%d: safe\n", insn_idx);
}
goto process_bpf_exit;
}
if (need_resched())
cond_resched();
- if (log_level > 1 || (log_level && do_print_state)) {
- if (log_level > 1)
- verbose("%d:", insn_idx);
+ if (env->log.level > 1 || (env->log.level && do_print_state)) {
+ if (env->log.level > 1)
+ verbose(env, "%d:", insn_idx);
else
- verbose("\nfrom %d to %d:",
+ verbose(env, "\nfrom %d to %d:",
prev_insn_idx, insn_idx);
- print_verifier_state(&env->cur_state);
+ print_verifier_state(env, state);
do_print_state = false;
}
- if (log_level) {
- verbose("%d: ", insn_idx);
- print_bpf_insn(env, insn);
+ if (env->log.level) {
+ verbose(env, "%d: ", insn_idx);
+ print_bpf_insn(verbose, env, insn,
+ env->allow_ptr_leaks);
}
err = ext_analyzer_insn_hook(env, insn_idx, prev_insn_idx);
if (err)
return err;
+ regs = cur_regs(env);
if (class == BPF_ALU || class == BPF_ALU64) {
err = check_alu_op(env, insn);
if (err)
* src_reg == stack|map in some other branch.
* Reject it.
*/
- verbose("same insn cannot be used with different pointers\n");
+ verbose(env, "same insn cannot be used with different pointers\n");
return -EINVAL;
}
} else if (dst_reg_type != *prev_dst_type &&
(dst_reg_type == PTR_TO_CTX ||
*prev_dst_type == PTR_TO_CTX)) {
- verbose("same insn cannot be used with different pointers\n");
+ verbose(env, "same insn cannot be used with different pointers\n");
return -EINVAL;
}
} else if (class == BPF_ST) {
if (BPF_MODE(insn->code) != BPF_MEM ||
insn->src_reg != BPF_REG_0) {
- verbose("BPF_ST uses reserved fields\n");
+ verbose(env, "BPF_ST uses reserved fields\n");
return -EINVAL;
}
/* check src operand */
insn->off != 0 ||
insn->src_reg != BPF_REG_0 ||
insn->dst_reg != BPF_REG_0) {
- verbose("BPF_CALL uses reserved fields\n");
+ verbose(env, "BPF_CALL uses reserved fields\n");
return -EINVAL;
}
insn->imm != 0 ||
insn->src_reg != BPF_REG_0 ||
insn->dst_reg != BPF_REG_0) {
- verbose("BPF_JA uses reserved fields\n");
+ verbose(env, "BPF_JA uses reserved fields\n");
return -EINVAL;
}
insn->imm != 0 ||
insn->src_reg != BPF_REG_0 ||
insn->dst_reg != BPF_REG_0) {
- verbose("BPF_EXIT uses reserved fields\n");
+ verbose(env, "BPF_EXIT uses reserved fields\n");
return -EINVAL;
}
return err;
if (is_pointer_value(env, BPF_REG_0)) {
- verbose("R0 leaks addr as return value\n");
+ verbose(env, "R0 leaks addr as return value\n");
return -EACCES;
}
+ err = check_return_code(env);
+ if (err)
+ return err;
process_bpf_exit:
- insn_idx = pop_stack(env, &prev_insn_idx);
- if (insn_idx < 0) {
+ err = pop_stack(env, &prev_insn_idx, &insn_idx);
+ if (err < 0) {
+ if (err != -ENOENT)
+ return err;
break;
} else {
do_print_state = true;
insn_idx++;
} else {
- verbose("invalid BPF_LD mode\n");
+ verbose(env, "invalid BPF_LD mode\n");
return -EINVAL;
}
} else {
- verbose("unknown insn class %d\n", class);
+ verbose(env, "unknown insn class %d\n", class);
return -EINVAL;
}
insn_idx++;
}
- verbose("processed %d insns, stack depth %d\n",
- insn_processed, env->prog->aux->stack_depth);
+ verbose(env, "processed %d insns, stack depth %d\n", insn_processed,
+ env->prog->aux->stack_depth);
return 0;
}
!(map->map_flags & BPF_F_NO_PREALLOC);
}
-static int check_map_prog_compatibility(struct bpf_map *map,
+static int check_map_prog_compatibility(struct bpf_verifier_env *env,
+ struct bpf_map *map,
struct bpf_prog *prog)
{
*/
if (prog->type == BPF_PROG_TYPE_PERF_EVENT) {
if (!check_map_prealloc(map)) {
- verbose("perf_event programs can only use preallocated hash map\n");
+ verbose(env, "perf_event programs can only use preallocated hash map\n");
return -EINVAL;
}
if (map->inner_map_meta &&
!check_map_prealloc(map->inner_map_meta)) {
- verbose("perf_event programs can only use preallocated inner hash map\n");
+ verbose(env, "perf_event programs can only use preallocated inner hash map\n");
return -EINVAL;
}
}
for (i = 0; i < insn_cnt; i++, insn++) {
if (BPF_CLASS(insn->code) == BPF_LDX &&
(BPF_MODE(insn->code) != BPF_MEM || insn->imm != 0)) {
- verbose("BPF_LDX uses reserved fields\n");
+ verbose(env, "BPF_LDX uses reserved fields\n");
return -EINVAL;
}
if (BPF_CLASS(insn->code) == BPF_STX &&
((BPF_MODE(insn->code) != BPF_MEM &&
BPF_MODE(insn->code) != BPF_XADD) || insn->imm != 0)) {
- verbose("BPF_STX uses reserved fields\n");
+ verbose(env, "BPF_STX uses reserved fields\n");
return -EINVAL;
}
if (i == insn_cnt - 1 || insn[1].code != 0 ||
insn[1].dst_reg != 0 || insn[1].src_reg != 0 ||
insn[1].off != 0) {
- verbose("invalid bpf_ld_imm64 insn\n");
+ verbose(env, "invalid bpf_ld_imm64 insn\n");
return -EINVAL;
}
goto next_insn;
if (insn->src_reg != BPF_PSEUDO_MAP_FD) {
- verbose("unrecognized bpf_ld_imm64 insn\n");
+ verbose(env,
+ "unrecognized bpf_ld_imm64 insn\n");
return -EINVAL;
}
f = fdget(insn->imm);
map = __bpf_map_get(f);
if (IS_ERR(map)) {
- verbose("fd %d is not pointing to valid bpf_map\n",
+ verbose(env, "fd %d is not pointing to valid bpf_map\n",
insn->imm);
return PTR_ERR(map);
}
- err = check_map_prog_compatibility(map, env->prog);
+ err = check_map_prog_compatibility(env, map, env->prog);
if (err) {
fdput(f);
return err;
*/
static int convert_ctx_accesses(struct bpf_verifier_env *env)
{
- const struct bpf_verifier_ops *ops = env->prog->aux->ops;
+ const struct bpf_verifier_ops *ops = env->ops;
int i, cnt, size, ctx_field_size, delta = 0;
const int insn_cnt = env->prog->len;
struct bpf_insn insn_buf[16], *insn;
cnt = ops->gen_prologue(insn_buf, env->seen_direct_write,
env->prog);
if (cnt >= ARRAY_SIZE(insn_buf)) {
- verbose("bpf verifier is misconfigured\n");
+ verbose(env, "bpf verifier is misconfigured\n");
return -EINVAL;
} else if (cnt) {
new_prog = bpf_patch_insn_data(env, 0, insn_buf, cnt);
u8 size_code;
if (type == BPF_WRITE) {
- verbose("bpf verifier narrow ctx access misconfigured\n");
+ verbose(env, "bpf verifier narrow ctx access misconfigured\n");
return -EINVAL;
}
&target_size);
if (cnt == 0 || cnt >= ARRAY_SIZE(insn_buf) ||
(ctx_field_size && !target_size)) {
- verbose("bpf verifier is misconfigured\n");
+ verbose(env, "bpf verifier is misconfigured\n");
return -EINVAL;
}
cnt = map_ptr->ops->map_gen_lookup(map_ptr, insn_buf);
if (cnt == 0 || cnt >= ARRAY_SIZE(insn_buf)) {
- verbose("bpf verifier is misconfigured\n");
+ verbose(env, "bpf verifier is misconfigured\n");
return -EINVAL;
}
insn = new_prog->insnsi + i + delta;
}
patch_call_imm:
- fn = prog->aux->ops->get_func_proto(insn->imm);
+ fn = env->ops->get_func_proto(insn->imm);
/* all functions that have prototype and verifier allowed
* programs to call them, must be real in-kernel functions
*/
if (!fn->func) {
- verbose("kernel subsystem misconfigured func %s#%d\n",
+ verbose(env,
+ "kernel subsystem misconfigured func %s#%d\n",
func_id_name(insn->imm), insn->imm);
return -EFAULT;
}
if (sl)
while (sl != STATE_LIST_MARK) {
sln = sl->next;
+ free_verifier_state(&sl->state, false);
kfree(sl);
sl = sln;
}
int bpf_check(struct bpf_prog **prog, union bpf_attr *attr)
{
- char __user *log_ubuf = NULL;
struct bpf_verifier_env *env;
+ struct bpf_verifer_log *log;
int ret = -EINVAL;
+ /* no program is valid */
+ if (ARRAY_SIZE(bpf_verifier_ops) == 0)
+ return -EINVAL;
+
/* 'struct bpf_verifier_env' can be global, but since it's not small,
* allocate/free it every time bpf_check() is called
*/
env = kzalloc(sizeof(struct bpf_verifier_env), GFP_KERNEL);
if (!env)
return -ENOMEM;
+ log = &env->log;
env->insn_aux_data = vzalloc(sizeof(struct bpf_insn_aux_data) *
(*prog)->len);
if (!env->insn_aux_data)
goto err_free_env;
env->prog = *prog;
+ env->ops = bpf_verifier_ops[env->prog->type];
/* grab the mutex to protect few globals used by verifier */
mutex_lock(&bpf_verifier_lock);
/* user requested verbose verifier output
* and supplied buffer to store the verification trace
*/
- log_level = attr->log_level;
- log_ubuf = (char __user *) (unsigned long) attr->log_buf;
- log_size = attr->log_size;
- log_len = 0;
+ log->level = attr->log_level;
+ log->ubuf = (char __user *) (unsigned long) attr->log_buf;
+ log->len_total = attr->log_size;
ret = -EINVAL;
- /* log_* values have to be sane */
- if (log_size < 128 || log_size > UINT_MAX >> 8 ||
- log_level == 0 || log_ubuf == NULL)
- goto err_unlock;
-
- ret = -ENOMEM;
- log_buf = vmalloc(log_size);
- if (!log_buf)
+ /* log attributes have to be sane */
+ if (log->len_total < 128 || log->len_total > UINT_MAX >> 8 ||
+ !log->level || !log->ubuf)
goto err_unlock;
- } else {
- log_level = 0;
}
env->strict_alignment = !!(attr->prog_flags & BPF_F_STRICT_ALIGNMENT);
env->allow_ptr_leaks = capable(CAP_SYS_ADMIN);
ret = do_check(env);
+ free_verifier_state(env->cur_state, true);
+ env->cur_state = NULL;
skip_full_check:
- while (pop_stack(env, NULL) >= 0);
+ while (!pop_stack(env, NULL, NULL));
free_states(env);
if (ret == 0)
if (ret == 0)
ret = fixup_bpf_calls(env);
- if (log_level && log_len >= log_size - 1) {
- BUG_ON(log_len >= log_size);
- /* verifier log exceeded user supplied buffer */
+ if (log->level && bpf_verifier_log_full(log))
ret = -ENOSPC;
- /* fall through to return what was recorded */
- }
-
- /* copy verifier log back to user space including trailing zero */
- if (log_level && copy_to_user(log_ubuf, log_buf, log_len + 1) != 0) {
+ if (log->level && !log->ubuf) {
ret = -EFAULT;
- goto free_log_buf;
+ goto err_release_maps;
}
if (ret == 0 && env->used_map_cnt) {
if (!env->prog->aux->used_maps) {
ret = -ENOMEM;
- goto free_log_buf;
+ goto err_release_maps;
}
memcpy(env->prog->aux->used_maps, env->used_maps,
convert_pseudo_ld_imm64(env);
}
-free_log_buf:
- if (log_level)
- vfree(log_buf);
+err_release_maps:
if (!env->prog->aux->used_maps)
/* if we didn't copy map pointers into bpf_prog_info, release
* them now. Otherwise free_bpf_prog_info() will release them.
return ret;
}
+static const struct bpf_verifier_ops * const bpf_analyzer_ops[] = {
+#ifdef CONFIG_NET
+ [BPF_PROG_TYPE_XDP] = &xdp_analyzer_ops,
+ [BPF_PROG_TYPE_SCHED_CLS] = &tc_cls_act_analyzer_ops,
+#endif
+};
+
int bpf_analyzer(struct bpf_prog *prog, const struct bpf_ext_analyzer_ops *ops,
void *priv)
{
struct bpf_verifier_env *env;
int ret;
+ if (prog->type >= ARRAY_SIZE(bpf_analyzer_ops) ||
+ !bpf_analyzer_ops[prog->type])
+ return -EOPNOTSUPP;
+
env = kzalloc(sizeof(struct bpf_verifier_env), GFP_KERNEL);
if (!env)
return -ENOMEM;
if (!env->insn_aux_data)
goto err_free_env;
env->prog = prog;
+ env->ops = bpf_analyzer_ops[env->prog->type];
env->analyzer_ops = ops;
env->analyzer_priv = priv;
/* grab the mutex to protect few globals used by verifier */
mutex_lock(&bpf_verifier_lock);
- log_level = 0;
-
env->strict_alignment = false;
if (!IS_ENABLED(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS))
env->strict_alignment = true;
env->allow_ptr_leaks = capable(CAP_SYS_ADMIN);
ret = do_check(env);
+ free_verifier_state(env->cur_state, true);
+ env->cur_state = NULL;
skip_full_check:
- while (pop_stack(env, NULL) >= 0);
+ while (!pop_stack(env, NULL, NULL));
free_states(env);
mutex_unlock(&bpf_verifier_lock);
projects / mirror_ubuntu-hirsute-kernel.git / blobdiff