#include <linux/sort.h>
#include <linux/perf_event.h>
#include <linux/ctype.h>
+#include <linux/error-injection.h>
+#include <linux/bpf_lsm.h>
#include "disasm.h"
reg->umax_value));
}
-static void __reg_bound_offset32(struct bpf_reg_state *reg)
-{
- u64 mask = 0xffffFFFF;
- struct tnum range = tnum_range(reg->umin_value & mask,
- reg->umax_value & mask);
- struct tnum lo32 = tnum_cast(reg->var_off, 4);
- struct tnum hi32 = tnum_lshift(tnum_rshift(reg->var_off, 32), 32);
-
- reg->var_off = tnum_or(hi32, tnum_intersect(lo32, range));
-}
-
/* Reset the min/max bounds of a register */
static void __mark_reg_unbounded(struct bpf_reg_state *reg)
{
expected_type = CONST_PTR_TO_MAP;
if (type != expected_type)
goto err_type;
- } else if (arg_type == ARG_PTR_TO_CTX) {
+ } else if (arg_type == ARG_PTR_TO_CTX ||
+ arg_type == ARG_PTR_TO_CTX_OR_NULL) {
expected_type = PTR_TO_CTX;
- if (type != expected_type)
- goto err_type;
- err = check_ctx_reg(env, reg, regno);
- if (err < 0)
- return err;
+ if (!(register_is_null(reg) &&
+ arg_type == ARG_PTR_TO_CTX_OR_NULL)) {
+ if (type != expected_type)
+ goto err_type;
+ err = check_ctx_reg(env, reg, regno);
+ if (err < 0)
+ return err;
+ }
} else if (arg_type == ARG_PTR_TO_SOCK_COMMON) {
expected_type = PTR_TO_SOCK_COMMON;
/* Any sk pointer can be ARG_PTR_TO_SOCK_COMMON */
if (func_id != BPF_FUNC_perf_event_read &&
func_id != BPF_FUNC_perf_event_output &&
func_id != BPF_FUNC_skb_output &&
- func_id != BPF_FUNC_perf_event_read_value)
+ func_id != BPF_FUNC_perf_event_read_value &&
+ func_id != BPF_FUNC_xdp_output)
goto error;
break;
case BPF_MAP_TYPE_STACK_TRACE:
if (func_id != BPF_FUNC_sk_redirect_map &&
func_id != BPF_FUNC_sock_map_update &&
func_id != BPF_FUNC_map_delete_elem &&
- func_id != BPF_FUNC_msg_redirect_map)
+ func_id != BPF_FUNC_msg_redirect_map &&
+ func_id != BPF_FUNC_sk_select_reuseport)
goto error;
break;
case BPF_MAP_TYPE_SOCKHASH:
if (func_id != BPF_FUNC_sk_redirect_hash &&
func_id != BPF_FUNC_sock_hash_update &&
func_id != BPF_FUNC_map_delete_elem &&
- func_id != BPF_FUNC_msg_redirect_hash)
+ func_id != BPF_FUNC_msg_redirect_hash &&
+ func_id != BPF_FUNC_sk_select_reuseport)
goto error;
break;
case BPF_MAP_TYPE_REUSEPORT_SOCKARRAY:
case BPF_FUNC_perf_event_output:
case BPF_FUNC_perf_event_read_value:
case BPF_FUNC_skb_output:
+ case BPF_FUNC_xdp_output:
if (map->map_type != BPF_MAP_TYPE_PERF_EVENT_ARRAY)
goto error;
break;
goto error;
break;
case BPF_FUNC_sk_select_reuseport:
- if (map->map_type != BPF_MAP_TYPE_REUSEPORT_SOCKARRAY)
+ if (map->map_type != BPF_MAP_TYPE_REUSEPORT_SOCKARRAY &&
+ map->map_type != BPF_MAP_TYPE_SOCKMAP &&
+ map->map_type != BPF_MAP_TYPE_SOCKHASH)
goto error;
break;
case BPF_FUNC_map_peek_elem:
return 0;
}
+static void scalar_min_max_add(struct bpf_reg_state *dst_reg,
+ struct bpf_reg_state *src_reg)
+{
+ s64 smin_val = src_reg->smin_value;
+ s64 smax_val = src_reg->smax_value;
+ u64 umin_val = src_reg->umin_value;
+ u64 umax_val = src_reg->umax_value;
+
+ if (signed_add_overflows(dst_reg->smin_value, smin_val) ||
+ signed_add_overflows(dst_reg->smax_value, smax_val)) {
+ dst_reg->smin_value = S64_MIN;
+ dst_reg->smax_value = S64_MAX;
+ } else {
+ dst_reg->smin_value += smin_val;
+ dst_reg->smax_value += smax_val;
+ }
+ if (dst_reg->umin_value + umin_val < umin_val ||
+ dst_reg->umax_value + umax_val < umax_val) {
+ dst_reg->umin_value = 0;
+ dst_reg->umax_value = U64_MAX;
+ } else {
+ dst_reg->umin_value += umin_val;
+ dst_reg->umax_value += umax_val;
+ }
+ dst_reg->var_off = tnum_add(dst_reg->var_off, src_reg->var_off);
+}
+
+static void scalar_min_max_sub(struct bpf_reg_state *dst_reg,
+ struct bpf_reg_state *src_reg)
+{
+ s64 smin_val = src_reg->smin_value;
+ s64 smax_val = src_reg->smax_value;
+ u64 umin_val = src_reg->umin_value;
+ u64 umax_val = src_reg->umax_value;
+
+ if (signed_sub_overflows(dst_reg->smin_value, smax_val) ||
+ signed_sub_overflows(dst_reg->smax_value, smin_val)) {
+ /* Overflow possible, we know nothing */
+ dst_reg->smin_value = S64_MIN;
+ dst_reg->smax_value = S64_MAX;
+ } else {
+ dst_reg->smin_value -= smax_val;
+ dst_reg->smax_value -= smin_val;
+ }
+ if (dst_reg->umin_value < umax_val) {
+ /* Overflow possible, we know nothing */
+ dst_reg->umin_value = 0;
+ dst_reg->umax_value = U64_MAX;
+ } else {
+ /* Cannot overflow (as long as bounds are consistent) */
+ dst_reg->umin_value -= umax_val;
+ dst_reg->umax_value -= umin_val;
+ }
+ dst_reg->var_off = tnum_sub(dst_reg->var_off, src_reg->var_off);
+}
+
+static void scalar_min_max_mul(struct bpf_reg_state *dst_reg,
+ struct bpf_reg_state *src_reg)
+{
+ s64 smin_val = src_reg->smin_value;
+ u64 umin_val = src_reg->umin_value;
+ u64 umax_val = src_reg->umax_value;
+
+ dst_reg->var_off = tnum_mul(dst_reg->var_off, src_reg->var_off);
+ if (smin_val < 0 || dst_reg->smin_value < 0) {
+ /* Ain't nobody got time to multiply that sign */
+ __mark_reg_unbounded(dst_reg);
+ __update_reg_bounds(dst_reg);
+ return;
+ }
+ /* Both values are positive, so we can work with unsigned and
+ * copy the result to signed (unless it exceeds S64_MAX).
+ */
+ if (umax_val > U32_MAX || dst_reg->umax_value > U32_MAX) {
+ /* Potential overflow, we know nothing */
+ __mark_reg_unbounded(dst_reg);
+ /* (except what we can learn from the var_off) */
+ __update_reg_bounds(dst_reg);
+ return;
+ }
+ dst_reg->umin_value *= umin_val;
+ dst_reg->umax_value *= umax_val;
+ if (dst_reg->umax_value > S64_MAX) {
+ /* Overflow possible, we know nothing */
+ dst_reg->smin_value = S64_MIN;
+ dst_reg->smax_value = S64_MAX;
+ } else {
+ dst_reg->smin_value = dst_reg->umin_value;
+ dst_reg->smax_value = dst_reg->umax_value;
+ }
+}
+
+static void scalar_min_max_and(struct bpf_reg_state *dst_reg,
+ struct bpf_reg_state *src_reg)
+{
+ s64 smin_val = src_reg->smin_value;
+ u64 umax_val = src_reg->umax_value;
+
+ /* We get our minimum from the var_off, since that's inherently
+ * bitwise. Our maximum is the minimum of the operands' maxima.
+ */
+ dst_reg->var_off = tnum_and(dst_reg->var_off, src_reg->var_off);
+ dst_reg->umin_value = dst_reg->var_off.value;
+ dst_reg->umax_value = min(dst_reg->umax_value, umax_val);
+ if (dst_reg->smin_value < 0 || smin_val < 0) {
+ /* Lose signed bounds when ANDing negative numbers,
+ * ain't nobody got time for that.
+ */
+ dst_reg->smin_value = S64_MIN;
+ dst_reg->smax_value = S64_MAX;
+ } else {
+ /* ANDing two positives gives a positive, so safe to
+ * cast result into s64.
+ */
+ dst_reg->smin_value = dst_reg->umin_value;
+ dst_reg->smax_value = dst_reg->umax_value;
+ }
+ /* We may learn something more from the var_off */
+ __update_reg_bounds(dst_reg);
+}
+
+static void scalar_min_max_or(struct bpf_reg_state *dst_reg,
+ struct bpf_reg_state *src_reg)
+{
+ s64 smin_val = src_reg->smin_value;
+ u64 umin_val = src_reg->umin_value;
+
+ /* We get our maximum from the var_off, and our minimum is the
+ * maximum of the operands' minima
+ */
+ dst_reg->var_off = tnum_or(dst_reg->var_off, src_reg->var_off);
+ dst_reg->umin_value = max(dst_reg->umin_value, umin_val);
+ dst_reg->umax_value = dst_reg->var_off.value | dst_reg->var_off.mask;
+ if (dst_reg->smin_value < 0 || smin_val < 0) {
+ /* Lose signed bounds when ORing negative numbers,
+ * ain't nobody got time for that.
+ */
+ dst_reg->smin_value = S64_MIN;
+ dst_reg->smax_value = S64_MAX;
+ } else {
+ /* ORing two positives gives a positive, so safe to
+ * cast result into s64.
+ */
+ dst_reg->smin_value = dst_reg->umin_value;
+ dst_reg->smax_value = dst_reg->umax_value;
+ }
+ /* We may learn something more from the var_off */
+ __update_reg_bounds(dst_reg);
+}
+
+static void scalar_min_max_lsh(struct bpf_reg_state *dst_reg,
+ struct bpf_reg_state *src_reg)
+{
+ u64 umax_val = src_reg->umax_value;
+ u64 umin_val = src_reg->umin_value;
+
+ /* We lose all sign bit information (except what we can pick
+ * up from var_off)
+ */
+ dst_reg->smin_value = S64_MIN;
+ dst_reg->smax_value = S64_MAX;
+ /* If we might shift our top bit out, then we know nothing */
+ if (dst_reg->umax_value > 1ULL << (63 - umax_val)) {
+ dst_reg->umin_value = 0;
+ dst_reg->umax_value = U64_MAX;
+ } else {
+ dst_reg->umin_value <<= umin_val;
+ dst_reg->umax_value <<= umax_val;
+ }
+ dst_reg->var_off = tnum_lshift(dst_reg->var_off, umin_val);
+ /* We may learn something more from the var_off */
+ __update_reg_bounds(dst_reg);
+}
+
+static void scalar_min_max_rsh(struct bpf_reg_state *dst_reg,
+ struct bpf_reg_state *src_reg)
+{
+ u64 umax_val = src_reg->umax_value;
+ u64 umin_val = src_reg->umin_value;
+
+ /* BPF_RSH is an unsigned shift. If the value in dst_reg might
+ * be negative, then either:
+ * 1) src_reg might be zero, so the sign bit of the result is
+ * unknown, so we lose our signed bounds
+ * 2) it's known negative, thus the unsigned bounds capture the
+ * signed bounds
+ * 3) the signed bounds cross zero, so they tell us nothing
+ * about the result
+ * If the value in dst_reg is known nonnegative, then again the
+ * unsigned bounts capture the signed bounds.
+ * Thus, in all cases it suffices to blow away our signed bounds
+ * and rely on inferring new ones from the unsigned bounds and
+ * var_off of the result.
+ */
+ dst_reg->smin_value = S64_MIN;
+ dst_reg->smax_value = S64_MAX;
+ dst_reg->var_off = tnum_rshift(dst_reg->var_off, umin_val);
+ dst_reg->umin_value >>= umax_val;
+ dst_reg->umax_value >>= umin_val;
+ /* We may learn something more from the var_off */
+ __update_reg_bounds(dst_reg);
+}
+
+static void scalar_min_max_arsh(struct bpf_reg_state *dst_reg,
+ struct bpf_reg_state *src_reg,
+ u64 insn_bitness)
+{
+ u64 umin_val = src_reg->umin_value;
+
+ /* Upon reaching here, src_known is true and
+ * umax_val is equal to umin_val.
+ */
+ if (insn_bitness == 32) {
+ dst_reg->smin_value = (u32)(((s32)dst_reg->smin_value) >> umin_val);
+ dst_reg->smax_value = (u32)(((s32)dst_reg->smax_value) >> umin_val);
+ } else {
+ dst_reg->smin_value >>= umin_val;
+ dst_reg->smax_value >>= umin_val;
+ }
+
+ dst_reg->var_off = tnum_arshift(dst_reg->var_off, umin_val,
+ insn_bitness);
+
+ /* blow away the dst_reg umin_value/umax_value and rely on
+ * dst_reg var_off to refine the result.
+ */
+ dst_reg->umin_value = 0;
+ dst_reg->umax_value = U64_MAX;
+ __update_reg_bounds(dst_reg);
+}
+
/* WARNING: This function does calculations on 64-bit values, but the actual
* execution may occur on 32-bit values. Therefore, things like bitshifts
* need extra checks in the 32-bit case.
verbose(env, "R%d tried to add from different pointers or scalars\n", dst);
return ret;
}
- if (signed_add_overflows(dst_reg->smin_value, smin_val) ||
- signed_add_overflows(dst_reg->smax_value, smax_val)) {
- dst_reg->smin_value = S64_MIN;
- dst_reg->smax_value = S64_MAX;
- } else {
- dst_reg->smin_value += smin_val;
- dst_reg->smax_value += smax_val;
- }
- if (dst_reg->umin_value + umin_val < umin_val ||
- dst_reg->umax_value + umax_val < umax_val) {
- dst_reg->umin_value = 0;
- dst_reg->umax_value = U64_MAX;
- } else {
- dst_reg->umin_value += umin_val;
- dst_reg->umax_value += umax_val;
- }
- dst_reg->var_off = tnum_add(dst_reg->var_off, src_reg.var_off);
+ scalar_min_max_add(dst_reg, &src_reg);
break;
case BPF_SUB:
ret = sanitize_val_alu(env, insn);
verbose(env, "R%d tried to sub from different pointers or scalars\n", dst);
return ret;
}
- if (signed_sub_overflows(dst_reg->smin_value, smax_val) ||
- signed_sub_overflows(dst_reg->smax_value, smin_val)) {
- /* Overflow possible, we know nothing */
- dst_reg->smin_value = S64_MIN;
- dst_reg->smax_value = S64_MAX;
- } else {
- dst_reg->smin_value -= smax_val;
- dst_reg->smax_value -= smin_val;
- }
- if (dst_reg->umin_value < umax_val) {
- /* Overflow possible, we know nothing */
- dst_reg->umin_value = 0;
- dst_reg->umax_value = U64_MAX;
- } else {
- /* Cannot overflow (as long as bounds are consistent) */
- dst_reg->umin_value -= umax_val;
- dst_reg->umax_value -= umin_val;
- }
- dst_reg->var_off = tnum_sub(dst_reg->var_off, src_reg.var_off);
+ scalar_min_max_sub(dst_reg, &src_reg);
break;
case BPF_MUL:
- dst_reg->var_off = tnum_mul(dst_reg->var_off, src_reg.var_off);
- if (smin_val < 0 || dst_reg->smin_value < 0) {
- /* Ain't nobody got time to multiply that sign */
- __mark_reg_unbounded(dst_reg);
- __update_reg_bounds(dst_reg);
- break;
- }
- /* Both values are positive, so we can work with unsigned and
- * copy the result to signed (unless it exceeds S64_MAX).
- */
- if (umax_val > U32_MAX || dst_reg->umax_value > U32_MAX) {
- /* Potential overflow, we know nothing */
- __mark_reg_unbounded(dst_reg);
- /* (except what we can learn from the var_off) */
- __update_reg_bounds(dst_reg);
- break;
- }
- dst_reg->umin_value *= umin_val;
- dst_reg->umax_value *= umax_val;
- if (dst_reg->umax_value > S64_MAX) {
- /* Overflow possible, we know nothing */
- dst_reg->smin_value = S64_MIN;
- dst_reg->smax_value = S64_MAX;
- } else {
- dst_reg->smin_value = dst_reg->umin_value;
- dst_reg->smax_value = dst_reg->umax_value;
- }
+ scalar_min_max_mul(dst_reg, &src_reg);
break;
case BPF_AND:
if (src_known && dst_known) {
src_reg.var_off.value);
break;
}
- /* We get our minimum from the var_off, since that's inherently
- * bitwise. Our maximum is the minimum of the operands' maxima.
- */
- dst_reg->var_off = tnum_and(dst_reg->var_off, src_reg.var_off);
- dst_reg->umin_value = dst_reg->var_off.value;
- dst_reg->umax_value = min(dst_reg->umax_value, umax_val);
- if (dst_reg->smin_value < 0 || smin_val < 0) {
- /* Lose signed bounds when ANDing negative numbers,
- * ain't nobody got time for that.
- */
- dst_reg->smin_value = S64_MIN;
- dst_reg->smax_value = S64_MAX;
- } else {
- /* ANDing two positives gives a positive, so safe to
- * cast result into s64.
- */
- dst_reg->smin_value = dst_reg->umin_value;
- dst_reg->smax_value = dst_reg->umax_value;
- }
- /* We may learn something more from the var_off */
- __update_reg_bounds(dst_reg);
+ scalar_min_max_and(dst_reg, &src_reg);
break;
case BPF_OR:
if (src_known && dst_known) {
src_reg.var_off.value);
break;
}
- /* We get our maximum from the var_off, and our minimum is the
- * maximum of the operands' minima
- */
- dst_reg->var_off = tnum_or(dst_reg->var_off, src_reg.var_off);
- dst_reg->umin_value = max(dst_reg->umin_value, umin_val);
- dst_reg->umax_value = dst_reg->var_off.value |
- dst_reg->var_off.mask;
- if (dst_reg->smin_value < 0 || smin_val < 0) {
- /* Lose signed bounds when ORing negative numbers,
- * ain't nobody got time for that.
- */
- dst_reg->smin_value = S64_MIN;
- dst_reg->smax_value = S64_MAX;
- } else {
- /* ORing two positives gives a positive, so safe to
- * cast result into s64.
- */
- dst_reg->smin_value = dst_reg->umin_value;
- dst_reg->smax_value = dst_reg->umax_value;
- }
- /* We may learn something more from the var_off */
- __update_reg_bounds(dst_reg);
+ scalar_min_max_or(dst_reg, &src_reg);
break;
case BPF_LSH:
if (umax_val >= insn_bitness) {
mark_reg_unknown(env, regs, insn->dst_reg);
break;
}
- /* We lose all sign bit information (except what we can pick
- * up from var_off)
- */
- dst_reg->smin_value = S64_MIN;
- dst_reg->smax_value = S64_MAX;
- /* If we might shift our top bit out, then we know nothing */
- if (dst_reg->umax_value > 1ULL << (63 - umax_val)) {
- dst_reg->umin_value = 0;
- dst_reg->umax_value = U64_MAX;
- } else {
- dst_reg->umin_value <<= umin_val;
- dst_reg->umax_value <<= umax_val;
- }
- dst_reg->var_off = tnum_lshift(dst_reg->var_off, umin_val);
- /* We may learn something more from the var_off */
- __update_reg_bounds(dst_reg);
+ scalar_min_max_lsh(dst_reg, &src_reg);
break;
case BPF_RSH:
if (umax_val >= insn_bitness) {
mark_reg_unknown(env, regs, insn->dst_reg);
break;
}
- /* BPF_RSH is an unsigned shift. If the value in dst_reg might
- * be negative, then either:
- * 1) src_reg might be zero, so the sign bit of the result is
- * unknown, so we lose our signed bounds
- * 2) it's known negative, thus the unsigned bounds capture the
- * signed bounds
- * 3) the signed bounds cross zero, so they tell us nothing
- * about the result
- * If the value in dst_reg is known nonnegative, then again the
- * unsigned bounts capture the signed bounds.
- * Thus, in all cases it suffices to blow away our signed bounds
- * and rely on inferring new ones from the unsigned bounds and
- * var_off of the result.
- */
- dst_reg->smin_value = S64_MIN;
- dst_reg->smax_value = S64_MAX;
- dst_reg->var_off = tnum_rshift(dst_reg->var_off, umin_val);
- dst_reg->umin_value >>= umax_val;
- dst_reg->umax_value >>= umin_val;
- /* We may learn something more from the var_off */
- __update_reg_bounds(dst_reg);
+ scalar_min_max_rsh(dst_reg, &src_reg);
break;
case BPF_ARSH:
if (umax_val >= insn_bitness) {
mark_reg_unknown(env, regs, insn->dst_reg);
break;
}
-
- /* Upon reaching here, src_known is true and
- * umax_val is equal to umin_val.
- */
- if (insn_bitness == 32) {
- dst_reg->smin_value = (u32)(((s32)dst_reg->smin_value) >> umin_val);
- dst_reg->smax_value = (u32)(((s32)dst_reg->smax_value) >> umin_val);
- } else {
- dst_reg->smin_value >>= umin_val;
- dst_reg->smax_value >>= umin_val;
- }
-
- dst_reg->var_off = tnum_arshift(dst_reg->var_off, umin_val,
- insn_bitness);
-
- /* blow away the dst_reg umin_value/umax_value and rely on
- * dst_reg var_off to refine the result.
- */
- dst_reg->umin_value = 0;
- dst_reg->umax_value = U64_MAX;
- __update_reg_bounds(dst_reg);
+ scalar_min_max_arsh(dst_reg, &src_reg, insn_bitness);
break;
default:
mark_reg_unknown(env, regs, insn->dst_reg);
coerce_reg_to_size(dst_reg, 4);
}
+ __update_reg_bounds(dst_reg);
__reg_deduce_bounds(dst_reg);
__reg_bound_offset(dst_reg);
return 0;
/* We might have learned some bits from the bounds. */
__reg_bound_offset(false_reg);
__reg_bound_offset(true_reg);
- if (is_jmp32) {
- __reg_bound_offset32(false_reg);
- __reg_bound_offset32(true_reg);
- }
/* Intersecting with the old var_off might have improved our bounds
* slightly. e.g. if umax was 0x7f...f and var_off was (0; 0xf...fc),
* then new var_off is (0; 0x7f...fc) which improves our umax.
/* We might have learned some bits from the bounds. */
__reg_bound_offset(false_reg);
__reg_bound_offset(true_reg);
- if (is_jmp32) {
- __reg_bound_offset32(false_reg);
- __reg_bound_offset32(true_reg);
- }
/* Intersecting with the old var_off might have improved our bounds
* slightly. e.g. if umax was 0x7f...f and var_off was (0; 0xf...fc),
* then new var_off is (0; 0x7f...fc) which improves our umax.
struct tnum range = tnum_range(0, 1);
int err;
- /* The struct_ops func-ptr's return type could be "void" */
- if (env->prog->type == BPF_PROG_TYPE_STRUCT_OPS &&
+ /* LSM and struct_ops func-ptr's return type could be "void" */
+ if ((env->prog->type == BPF_PROG_TYPE_STRUCT_OPS ||
+ env->prog->type == BPF_PROG_TYPE_LSM) &&
!prog->aux->attach_func_proto->type)
return 0;
}
}
+static bool is_preallocated_map(struct bpf_map *map)
+{
+ if (!check_map_prealloc(map))
+ return false;
+ if (map->inner_map_meta && !check_map_prealloc(map->inner_map_meta))
+ return false;
+ return true;
+}
+
static int check_map_prog_compatibility(struct bpf_verifier_env *env,
struct bpf_map *map,
struct bpf_prog *prog)
{
- /* Make sure that BPF_PROG_TYPE_PERF_EVENT programs only use
- * preallocated hash maps, since doing memory allocation
- * in overflow_handler can crash depending on where nmi got
- * triggered.
+ /*
+ * Validate that trace type programs use preallocated hash maps.
+ *
+ * For programs attached to PERF events this is mandatory as the
+ * perf NMI can hit any arbitrary code sequence.
+ *
+ * All other trace types using preallocated hash maps are unsafe as
+ * well because tracepoint or kprobes can be inside locked regions
+ * of the memory allocator or at a place where a recursion into the
+ * memory allocator would see inconsistent state.
+ *
+ * On RT enabled kernels run-time allocation of all trace type
+ * programs is strictly prohibited due to lock type constraints. On
+ * !RT kernels it is allowed for backwards compatibility reasons for
+ * now, but warnings are emitted so developers are made aware of
+ * the unsafety and can fix their programs before this is enforced.
*/
- if (prog->type == BPF_PROG_TYPE_PERF_EVENT) {
- if (!check_map_prealloc(map)) {
+ if (is_tracing_prog_type(prog->type) && !is_preallocated_map(map)) {
+ if (prog->type == BPF_PROG_TYPE_PERF_EVENT) {
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(env, "perf_event programs can only use preallocated inner hash map\n");
+ if (IS_ENABLED(CONFIG_PREEMPT_RT)) {
+ verbose(env, "trace type programs can only use preallocated hash map\n");
return -EINVAL;
}
+ WARN_ONCE(1, "trace type BPF program uses run-time allocation\n");
+ verbose(env, "trace type programs with run-time allocated hash maps are unsafe. Switch to preallocated hash maps.\n");
}
if ((is_tracing_prog_type(prog->type) ||
return 0;
}
+#define SECURITY_PREFIX "security_"
+
+static int check_attach_modify_return(struct bpf_verifier_env *env)
+{
+ struct bpf_prog *prog = env->prog;
+ unsigned long addr = (unsigned long) prog->aux->trampoline->func.addr;
+
+ /* This is expected to be cleaned up in the future with the KRSI effort
+ * introducing the LSM_HOOK macro for cleaning up lsm_hooks.h.
+ */
+ if (within_error_injection_list(addr) ||
+ !strncmp(SECURITY_PREFIX, prog->aux->attach_func_name,
+ sizeof(SECURITY_PREFIX) - 1))
+ return 0;
+
+ verbose(env, "fmod_ret attach_btf_id %u (%s) is not modifiable\n",
+ prog->aux->attach_btf_id, prog->aux->attach_func_name);
+
+ return -EINVAL;
+}
static int check_attach_btf_id(struct bpf_verifier_env *env)
{
if (prog->type == BPF_PROG_TYPE_STRUCT_OPS)
return check_struct_ops_btf_id(env);
- if (prog->type != BPF_PROG_TYPE_TRACING && !prog_extension)
+ if (prog->type != BPF_PROG_TYPE_TRACING &&
+ prog->type != BPF_PROG_TYPE_LSM &&
+ !prog_extension)
return 0;
if (!btf_id) {
if (!prog_extension)
return -EINVAL;
/* fallthrough */
+ case BPF_MODIFY_RETURN:
+ case BPF_LSM_MAC:
case BPF_TRACE_FENTRY:
case BPF_TRACE_FEXIT:
+ prog->aux->attach_func_name = tname;
+ if (prog->type == BPF_PROG_TYPE_LSM) {
+ ret = bpf_lsm_verify_prog(&env->log, prog);
+ if (ret < 0)
+ return ret;
+ }
+
if (!btf_type_is_func(t)) {
verbose(env, "attach_btf_id %u is not a function\n",
btf_id);
tr = bpf_trampoline_lookup(key);
if (!tr)
return -ENOMEM;
- prog->aux->attach_func_name = tname;
/* t is either vmlinux type or another program's type */
prog->aux->attach_func_proto = t;
mutex_lock(&tr->mutex);
}
tr->func.addr = (void *)addr;
prog->aux->trampoline = tr;
+
+ if (prog->expected_attach_type == BPF_MODIFY_RETURN)
+ ret = check_attach_modify_return(env);
out:
mutex_unlock(&tr->mutex);
if (ret)
projects / linux-2.6-microblaze.git / blobdiff