|  | // SPDX-License-Identifier: GPL-2.0-only | 
|  | /* Copyright (c) 2011-2014 PLUMgrid, http://plumgrid.com | 
|  | * Copyright (c) 2016,2017 Facebook | 
|  | */ | 
|  | #include <linux/bpf.h> | 
|  | #include <linux/btf.h> | 
|  | #include <linux/err.h> | 
|  | #include <linux/slab.h> | 
|  | #include <linux/mm.h> | 
|  | #include <linux/filter.h> | 
|  | #include <linux/perf_event.h> | 
|  | #include <uapi/linux/btf.h> | 
|  | #include <linux/rcupdate_trace.h> | 
|  | #include <linux/btf_ids.h> | 
|  |  | 
|  | #include "map_in_map.h" | 
|  |  | 
|  | #define ARRAY_CREATE_FLAG_MASK \ | 
|  | (BPF_F_NUMA_NODE | BPF_F_MMAPABLE | BPF_F_ACCESS_MASK | \ | 
|  | BPF_F_PRESERVE_ELEMS | BPF_F_INNER_MAP) | 
|  |  | 
|  | static void bpf_array_free_percpu(struct bpf_array *array) | 
|  | { | 
|  | int i; | 
|  |  | 
|  | for (i = 0; i < array->map.max_entries; i++) { | 
|  | free_percpu(array->pptrs[i]); | 
|  | cond_resched(); | 
|  | } | 
|  | } | 
|  |  | 
|  | static int bpf_array_alloc_percpu(struct bpf_array *array) | 
|  | { | 
|  | void __percpu *ptr; | 
|  | int i; | 
|  |  | 
|  | for (i = 0; i < array->map.max_entries; i++) { | 
|  | ptr = bpf_map_alloc_percpu(&array->map, array->elem_size, 8, | 
|  | GFP_USER | __GFP_NOWARN); | 
|  | if (!ptr) { | 
|  | bpf_array_free_percpu(array); | 
|  | return -ENOMEM; | 
|  | } | 
|  | array->pptrs[i] = ptr; | 
|  | cond_resched(); | 
|  | } | 
|  |  | 
|  | return 0; | 
|  | } | 
|  |  | 
|  | /* Called from syscall */ | 
|  | int array_map_alloc_check(union bpf_attr *attr) | 
|  | { | 
|  | bool percpu = attr->map_type == BPF_MAP_TYPE_PERCPU_ARRAY; | 
|  | int numa_node = bpf_map_attr_numa_node(attr); | 
|  |  | 
|  | /* check sanity of attributes */ | 
|  | if (attr->max_entries == 0 || attr->key_size != 4 || | 
|  | attr->value_size == 0 || | 
|  | attr->map_flags & ~ARRAY_CREATE_FLAG_MASK || | 
|  | !bpf_map_flags_access_ok(attr->map_flags) || | 
|  | (percpu && numa_node != NUMA_NO_NODE)) | 
|  | return -EINVAL; | 
|  |  | 
|  | if (attr->map_type != BPF_MAP_TYPE_ARRAY && | 
|  | attr->map_flags & (BPF_F_MMAPABLE | BPF_F_INNER_MAP)) | 
|  | return -EINVAL; | 
|  |  | 
|  | if (attr->map_type != BPF_MAP_TYPE_PERF_EVENT_ARRAY && | 
|  | attr->map_flags & BPF_F_PRESERVE_ELEMS) | 
|  | return -EINVAL; | 
|  |  | 
|  | /* avoid overflow on round_up(map->value_size) */ | 
|  | if (attr->value_size > INT_MAX) | 
|  | return -E2BIG; | 
|  | /* percpu map value size is bound by PCPU_MIN_UNIT_SIZE */ | 
|  | if (percpu && round_up(attr->value_size, 8) > PCPU_MIN_UNIT_SIZE) | 
|  | return -E2BIG; | 
|  |  | 
|  | return 0; | 
|  | } | 
|  |  | 
|  | static struct bpf_map *array_map_alloc(union bpf_attr *attr) | 
|  | { | 
|  | bool percpu = attr->map_type == BPF_MAP_TYPE_PERCPU_ARRAY; | 
|  | int numa_node = bpf_map_attr_numa_node(attr); | 
|  | u32 elem_size, index_mask, max_entries; | 
|  | bool bypass_spec_v1 = bpf_bypass_spec_v1(NULL); | 
|  | u64 array_size, mask64; | 
|  | struct bpf_array *array; | 
|  |  | 
|  | elem_size = round_up(attr->value_size, 8); | 
|  |  | 
|  | max_entries = attr->max_entries; | 
|  |  | 
|  | /* On 32 bit archs roundup_pow_of_two() with max_entries that has | 
|  | * upper most bit set in u32 space is undefined behavior due to | 
|  | * resulting 1U << 32, so do it manually here in u64 space. | 
|  | */ | 
|  | mask64 = fls_long(max_entries - 1); | 
|  | mask64 = 1ULL << mask64; | 
|  | mask64 -= 1; | 
|  |  | 
|  | index_mask = mask64; | 
|  | if (!bypass_spec_v1) { | 
|  | /* round up array size to nearest power of 2, | 
|  | * since cpu will speculate within index_mask limits | 
|  | */ | 
|  | max_entries = index_mask + 1; | 
|  | /* Check for overflows. */ | 
|  | if (max_entries < attr->max_entries) | 
|  | return ERR_PTR(-E2BIG); | 
|  | } | 
|  |  | 
|  | array_size = sizeof(*array); | 
|  | if (percpu) { | 
|  | array_size += (u64) max_entries * sizeof(void *); | 
|  | } else { | 
|  | /* rely on vmalloc() to return page-aligned memory and | 
|  | * ensure array->value is exactly page-aligned | 
|  | */ | 
|  | if (attr->map_flags & BPF_F_MMAPABLE) { | 
|  | array_size = PAGE_ALIGN(array_size); | 
|  | array_size += PAGE_ALIGN((u64) max_entries * elem_size); | 
|  | } else { | 
|  | array_size += (u64) max_entries * elem_size; | 
|  | } | 
|  | } | 
|  |  | 
|  | /* allocate all map elements and zero-initialize them */ | 
|  | if (attr->map_flags & BPF_F_MMAPABLE) { | 
|  | void *data; | 
|  |  | 
|  | /* kmalloc'ed memory can't be mmap'ed, use explicit vmalloc */ | 
|  | data = bpf_map_area_mmapable_alloc(array_size, numa_node); | 
|  | if (!data) | 
|  | return ERR_PTR(-ENOMEM); | 
|  | array = data + PAGE_ALIGN(sizeof(struct bpf_array)) | 
|  | - offsetof(struct bpf_array, value); | 
|  | } else { | 
|  | array = bpf_map_area_alloc(array_size, numa_node); | 
|  | } | 
|  | if (!array) | 
|  | return ERR_PTR(-ENOMEM); | 
|  | array->index_mask = index_mask; | 
|  | array->map.bypass_spec_v1 = bypass_spec_v1; | 
|  |  | 
|  | /* copy mandatory map attributes */ | 
|  | bpf_map_init_from_attr(&array->map, attr); | 
|  | array->elem_size = elem_size; | 
|  |  | 
|  | if (percpu && bpf_array_alloc_percpu(array)) { | 
|  | bpf_map_area_free(array); | 
|  | return ERR_PTR(-ENOMEM); | 
|  | } | 
|  |  | 
|  | return &array->map; | 
|  | } | 
|  |  | 
|  | static void *array_map_elem_ptr(struct bpf_array* array, u32 index) | 
|  | { | 
|  | return array->value + (u64)array->elem_size * index; | 
|  | } | 
|  |  | 
|  | /* Called from syscall or from eBPF program */ | 
|  | static void *array_map_lookup_elem(struct bpf_map *map, void *key) | 
|  | { | 
|  | struct bpf_array *array = container_of(map, struct bpf_array, map); | 
|  | u32 index = *(u32 *)key; | 
|  |  | 
|  | if (unlikely(index >= array->map.max_entries)) | 
|  | return NULL; | 
|  |  | 
|  | return array->value + (u64)array->elem_size * (index & array->index_mask); | 
|  | } | 
|  |  | 
|  | static int array_map_direct_value_addr(const struct bpf_map *map, u64 *imm, | 
|  | u32 off) | 
|  | { | 
|  | struct bpf_array *array = container_of(map, struct bpf_array, map); | 
|  |  | 
|  | if (map->max_entries != 1) | 
|  | return -ENOTSUPP; | 
|  | if (off >= map->value_size) | 
|  | return -EINVAL; | 
|  |  | 
|  | *imm = (unsigned long)array->value; | 
|  | return 0; | 
|  | } | 
|  |  | 
|  | static int array_map_direct_value_meta(const struct bpf_map *map, u64 imm, | 
|  | u32 *off) | 
|  | { | 
|  | struct bpf_array *array = container_of(map, struct bpf_array, map); | 
|  | u64 base = (unsigned long)array->value; | 
|  | u64 range = array->elem_size; | 
|  |  | 
|  | if (map->max_entries != 1) | 
|  | return -ENOTSUPP; | 
|  | if (imm < base || imm >= base + range) | 
|  | return -ENOENT; | 
|  |  | 
|  | *off = imm - base; | 
|  | return 0; | 
|  | } | 
|  |  | 
|  | /* emit BPF instructions equivalent to C code of array_map_lookup_elem() */ | 
|  | static int array_map_gen_lookup(struct bpf_map *map, struct bpf_insn *insn_buf) | 
|  | { | 
|  | struct bpf_array *array = container_of(map, struct bpf_array, map); | 
|  | struct bpf_insn *insn = insn_buf; | 
|  | u32 elem_size = array->elem_size; | 
|  | const int ret = BPF_REG_0; | 
|  | const int map_ptr = BPF_REG_1; | 
|  | const int index = BPF_REG_2; | 
|  |  | 
|  | if (map->map_flags & BPF_F_INNER_MAP) | 
|  | return -EOPNOTSUPP; | 
|  |  | 
|  | *insn++ = BPF_ALU64_IMM(BPF_ADD, map_ptr, offsetof(struct bpf_array, value)); | 
|  | *insn++ = BPF_LDX_MEM(BPF_W, ret, index, 0); | 
|  | if (!map->bypass_spec_v1) { | 
|  | *insn++ = BPF_JMP_IMM(BPF_JGE, ret, map->max_entries, 4); | 
|  | *insn++ = BPF_ALU32_IMM(BPF_AND, ret, array->index_mask); | 
|  | } else { | 
|  | *insn++ = BPF_JMP_IMM(BPF_JGE, ret, map->max_entries, 3); | 
|  | } | 
|  |  | 
|  | if (is_power_of_2(elem_size)) { | 
|  | *insn++ = BPF_ALU64_IMM(BPF_LSH, ret, ilog2(elem_size)); | 
|  | } else { | 
|  | *insn++ = BPF_ALU64_IMM(BPF_MUL, ret, elem_size); | 
|  | } | 
|  | *insn++ = BPF_ALU64_REG(BPF_ADD, ret, map_ptr); | 
|  | *insn++ = BPF_JMP_IMM(BPF_JA, 0, 0, 1); | 
|  | *insn++ = BPF_MOV64_IMM(ret, 0); | 
|  | return insn - insn_buf; | 
|  | } | 
|  |  | 
|  | /* Called from eBPF program */ | 
|  | static void *percpu_array_map_lookup_elem(struct bpf_map *map, void *key) | 
|  | { | 
|  | struct bpf_array *array = container_of(map, struct bpf_array, map); | 
|  | u32 index = *(u32 *)key; | 
|  |  | 
|  | if (unlikely(index >= array->map.max_entries)) | 
|  | return NULL; | 
|  |  | 
|  | return this_cpu_ptr(array->pptrs[index & array->index_mask]); | 
|  | } | 
|  |  | 
|  | /* emit BPF instructions equivalent to C code of percpu_array_map_lookup_elem() */ | 
|  | static int percpu_array_map_gen_lookup(struct bpf_map *map, struct bpf_insn *insn_buf) | 
|  | { | 
|  | struct bpf_array *array = container_of(map, struct bpf_array, map); | 
|  | struct bpf_insn *insn = insn_buf; | 
|  |  | 
|  | if (!bpf_jit_supports_percpu_insn()) | 
|  | return -EOPNOTSUPP; | 
|  |  | 
|  | if (map->map_flags & BPF_F_INNER_MAP) | 
|  | return -EOPNOTSUPP; | 
|  |  | 
|  | BUILD_BUG_ON(offsetof(struct bpf_array, map) != 0); | 
|  | *insn++ = BPF_ALU64_IMM(BPF_ADD, BPF_REG_1, offsetof(struct bpf_array, pptrs)); | 
|  |  | 
|  | *insn++ = BPF_LDX_MEM(BPF_W, BPF_REG_0, BPF_REG_2, 0); | 
|  | if (!map->bypass_spec_v1) { | 
|  | *insn++ = BPF_JMP_IMM(BPF_JGE, BPF_REG_0, map->max_entries, 6); | 
|  | *insn++ = BPF_ALU32_IMM(BPF_AND, BPF_REG_0, array->index_mask); | 
|  | } else { | 
|  | *insn++ = BPF_JMP_IMM(BPF_JGE, BPF_REG_0, map->max_entries, 5); | 
|  | } | 
|  |  | 
|  | *insn++ = BPF_ALU64_IMM(BPF_LSH, BPF_REG_0, 3); | 
|  | *insn++ = BPF_ALU64_REG(BPF_ADD, BPF_REG_0, BPF_REG_1); | 
|  | *insn++ = BPF_LDX_MEM(BPF_DW, BPF_REG_0, BPF_REG_0, 0); | 
|  | *insn++ = BPF_MOV64_PERCPU_REG(BPF_REG_0, BPF_REG_0); | 
|  | *insn++ = BPF_JMP_IMM(BPF_JA, 0, 0, 1); | 
|  | *insn++ = BPF_MOV64_IMM(BPF_REG_0, 0); | 
|  | return insn - insn_buf; | 
|  | } | 
|  |  | 
|  | static void *percpu_array_map_lookup_percpu_elem(struct bpf_map *map, void *key, u32 cpu) | 
|  | { | 
|  | struct bpf_array *array = container_of(map, struct bpf_array, map); | 
|  | u32 index = *(u32 *)key; | 
|  |  | 
|  | if (cpu >= nr_cpu_ids) | 
|  | return NULL; | 
|  |  | 
|  | if (unlikely(index >= array->map.max_entries)) | 
|  | return NULL; | 
|  |  | 
|  | return per_cpu_ptr(array->pptrs[index & array->index_mask], cpu); | 
|  | } | 
|  |  | 
|  | int bpf_percpu_array_copy(struct bpf_map *map, void *key, void *value) | 
|  | { | 
|  | struct bpf_array *array = container_of(map, struct bpf_array, map); | 
|  | u32 index = *(u32 *)key; | 
|  | void __percpu *pptr; | 
|  | int cpu, off = 0; | 
|  | u32 size; | 
|  |  | 
|  | if (unlikely(index >= array->map.max_entries)) | 
|  | return -ENOENT; | 
|  |  | 
|  | /* per_cpu areas are zero-filled and bpf programs can only | 
|  | * access 'value_size' of them, so copying rounded areas | 
|  | * will not leak any kernel data | 
|  | */ | 
|  | size = array->elem_size; | 
|  | rcu_read_lock(); | 
|  | pptr = array->pptrs[index & array->index_mask]; | 
|  | for_each_possible_cpu(cpu) { | 
|  | copy_map_value_long(map, value + off, per_cpu_ptr(pptr, cpu)); | 
|  | check_and_init_map_value(map, value + off); | 
|  | off += size; | 
|  | } | 
|  | rcu_read_unlock(); | 
|  | return 0; | 
|  | } | 
|  |  | 
|  | /* Called from syscall */ | 
|  | static int array_map_get_next_key(struct bpf_map *map, void *key, void *next_key) | 
|  | { | 
|  | struct bpf_array *array = container_of(map, struct bpf_array, map); | 
|  | u32 index = key ? *(u32 *)key : U32_MAX; | 
|  | u32 *next = (u32 *)next_key; | 
|  |  | 
|  | if (index >= array->map.max_entries) { | 
|  | *next = 0; | 
|  | return 0; | 
|  | } | 
|  |  | 
|  | if (index == array->map.max_entries - 1) | 
|  | return -ENOENT; | 
|  |  | 
|  | *next = index + 1; | 
|  | return 0; | 
|  | } | 
|  |  | 
|  | /* Called from syscall or from eBPF program */ | 
|  | static long array_map_update_elem(struct bpf_map *map, void *key, void *value, | 
|  | u64 map_flags) | 
|  | { | 
|  | struct bpf_array *array = container_of(map, struct bpf_array, map); | 
|  | u32 index = *(u32 *)key; | 
|  | char *val; | 
|  |  | 
|  | if (unlikely((map_flags & ~BPF_F_LOCK) > BPF_EXIST)) | 
|  | /* unknown flags */ | 
|  | return -EINVAL; | 
|  |  | 
|  | if (unlikely(index >= array->map.max_entries)) | 
|  | /* all elements were pre-allocated, cannot insert a new one */ | 
|  | return -E2BIG; | 
|  |  | 
|  | if (unlikely(map_flags & BPF_NOEXIST)) | 
|  | /* all elements already exist */ | 
|  | return -EEXIST; | 
|  |  | 
|  | if (unlikely((map_flags & BPF_F_LOCK) && | 
|  | !btf_record_has_field(map->record, BPF_SPIN_LOCK))) | 
|  | return -EINVAL; | 
|  |  | 
|  | if (array->map.map_type == BPF_MAP_TYPE_PERCPU_ARRAY) { | 
|  | val = this_cpu_ptr(array->pptrs[index & array->index_mask]); | 
|  | copy_map_value(map, val, value); | 
|  | bpf_obj_free_fields(array->map.record, val); | 
|  | } else { | 
|  | val = array->value + | 
|  | (u64)array->elem_size * (index & array->index_mask); | 
|  | if (map_flags & BPF_F_LOCK) | 
|  | copy_map_value_locked(map, val, value, false); | 
|  | else | 
|  | copy_map_value(map, val, value); | 
|  | bpf_obj_free_fields(array->map.record, val); | 
|  | } | 
|  | return 0; | 
|  | } | 
|  |  | 
|  | int bpf_percpu_array_update(struct bpf_map *map, void *key, void *value, | 
|  | u64 map_flags) | 
|  | { | 
|  | struct bpf_array *array = container_of(map, struct bpf_array, map); | 
|  | u32 index = *(u32 *)key; | 
|  | void __percpu *pptr; | 
|  | int cpu, off = 0; | 
|  | u32 size; | 
|  |  | 
|  | if (unlikely(map_flags > BPF_EXIST)) | 
|  | /* unknown flags */ | 
|  | return -EINVAL; | 
|  |  | 
|  | if (unlikely(index >= array->map.max_entries)) | 
|  | /* all elements were pre-allocated, cannot insert a new one */ | 
|  | return -E2BIG; | 
|  |  | 
|  | if (unlikely(map_flags == BPF_NOEXIST)) | 
|  | /* all elements already exist */ | 
|  | return -EEXIST; | 
|  |  | 
|  | /* the user space will provide round_up(value_size, 8) bytes that | 
|  | * will be copied into per-cpu area. bpf programs can only access | 
|  | * value_size of it. During lookup the same extra bytes will be | 
|  | * returned or zeros which were zero-filled by percpu_alloc, | 
|  | * so no kernel data leaks possible | 
|  | */ | 
|  | size = array->elem_size; | 
|  | rcu_read_lock(); | 
|  | pptr = array->pptrs[index & array->index_mask]; | 
|  | for_each_possible_cpu(cpu) { | 
|  | copy_map_value_long(map, per_cpu_ptr(pptr, cpu), value + off); | 
|  | bpf_obj_free_fields(array->map.record, per_cpu_ptr(pptr, cpu)); | 
|  | off += size; | 
|  | } | 
|  | rcu_read_unlock(); | 
|  | return 0; | 
|  | } | 
|  |  | 
|  | /* Called from syscall or from eBPF program */ | 
|  | static long array_map_delete_elem(struct bpf_map *map, void *key) | 
|  | { | 
|  | return -EINVAL; | 
|  | } | 
|  |  | 
|  | static void *array_map_vmalloc_addr(struct bpf_array *array) | 
|  | { | 
|  | return (void *)round_down((unsigned long)array, PAGE_SIZE); | 
|  | } | 
|  |  | 
|  | static void array_map_free_timers_wq(struct bpf_map *map) | 
|  | { | 
|  | struct bpf_array *array = container_of(map, struct bpf_array, map); | 
|  | int i; | 
|  |  | 
|  | /* We don't reset or free fields other than timer and workqueue | 
|  | * on uref dropping to zero. | 
|  | */ | 
|  | if (btf_record_has_field(map->record, BPF_TIMER | BPF_WORKQUEUE)) { | 
|  | for (i = 0; i < array->map.max_entries; i++) { | 
|  | if (btf_record_has_field(map->record, BPF_TIMER)) | 
|  | bpf_obj_free_timer(map->record, array_map_elem_ptr(array, i)); | 
|  | if (btf_record_has_field(map->record, BPF_WORKQUEUE)) | 
|  | bpf_obj_free_workqueue(map->record, array_map_elem_ptr(array, i)); | 
|  | } | 
|  | } | 
|  | } | 
|  |  | 
|  | /* Called when map->refcnt goes to zero, either from workqueue or from syscall */ | 
|  | static void array_map_free(struct bpf_map *map) | 
|  | { | 
|  | struct bpf_array *array = container_of(map, struct bpf_array, map); | 
|  | int i; | 
|  |  | 
|  | if (!IS_ERR_OR_NULL(map->record)) { | 
|  | if (array->map.map_type == BPF_MAP_TYPE_PERCPU_ARRAY) { | 
|  | for (i = 0; i < array->map.max_entries; i++) { | 
|  | void __percpu *pptr = array->pptrs[i & array->index_mask]; | 
|  | int cpu; | 
|  |  | 
|  | for_each_possible_cpu(cpu) { | 
|  | bpf_obj_free_fields(map->record, per_cpu_ptr(pptr, cpu)); | 
|  | cond_resched(); | 
|  | } | 
|  | } | 
|  | } else { | 
|  | for (i = 0; i < array->map.max_entries; i++) | 
|  | bpf_obj_free_fields(map->record, array_map_elem_ptr(array, i)); | 
|  | } | 
|  | } | 
|  |  | 
|  | if (array->map.map_type == BPF_MAP_TYPE_PERCPU_ARRAY) | 
|  | bpf_array_free_percpu(array); | 
|  |  | 
|  | if (array->map.map_flags & BPF_F_MMAPABLE) | 
|  | bpf_map_area_free(array_map_vmalloc_addr(array)); | 
|  | else | 
|  | bpf_map_area_free(array); | 
|  | } | 
|  |  | 
|  | static void array_map_seq_show_elem(struct bpf_map *map, void *key, | 
|  | struct seq_file *m) | 
|  | { | 
|  | void *value; | 
|  |  | 
|  | rcu_read_lock(); | 
|  |  | 
|  | value = array_map_lookup_elem(map, key); | 
|  | if (!value) { | 
|  | rcu_read_unlock(); | 
|  | return; | 
|  | } | 
|  |  | 
|  | if (map->btf_key_type_id) | 
|  | seq_printf(m, "%u: ", *(u32 *)key); | 
|  | btf_type_seq_show(map->btf, map->btf_value_type_id, value, m); | 
|  | seq_putc(m, '\n'); | 
|  |  | 
|  | rcu_read_unlock(); | 
|  | } | 
|  |  | 
|  | static void percpu_array_map_seq_show_elem(struct bpf_map *map, void *key, | 
|  | struct seq_file *m) | 
|  | { | 
|  | struct bpf_array *array = container_of(map, struct bpf_array, map); | 
|  | u32 index = *(u32 *)key; | 
|  | void __percpu *pptr; | 
|  | int cpu; | 
|  |  | 
|  | rcu_read_lock(); | 
|  |  | 
|  | seq_printf(m, "%u: {\n", *(u32 *)key); | 
|  | pptr = array->pptrs[index & array->index_mask]; | 
|  | for_each_possible_cpu(cpu) { | 
|  | seq_printf(m, "\tcpu%d: ", cpu); | 
|  | btf_type_seq_show(map->btf, map->btf_value_type_id, | 
|  | per_cpu_ptr(pptr, cpu), m); | 
|  | seq_putc(m, '\n'); | 
|  | } | 
|  | seq_puts(m, "}\n"); | 
|  |  | 
|  | rcu_read_unlock(); | 
|  | } | 
|  |  | 
|  | static int array_map_check_btf(const struct bpf_map *map, | 
|  | const struct btf *btf, | 
|  | const struct btf_type *key_type, | 
|  | const struct btf_type *value_type) | 
|  | { | 
|  | u32 int_data; | 
|  |  | 
|  | /* One exception for keyless BTF: .bss/.data/.rodata map */ | 
|  | if (btf_type_is_void(key_type)) { | 
|  | if (map->map_type != BPF_MAP_TYPE_ARRAY || | 
|  | map->max_entries != 1) | 
|  | return -EINVAL; | 
|  |  | 
|  | if (BTF_INFO_KIND(value_type->info) != BTF_KIND_DATASEC) | 
|  | return -EINVAL; | 
|  |  | 
|  | return 0; | 
|  | } | 
|  |  | 
|  | if (BTF_INFO_KIND(key_type->info) != BTF_KIND_INT) | 
|  | return -EINVAL; | 
|  |  | 
|  | int_data = *(u32 *)(key_type + 1); | 
|  | /* bpf array can only take a u32 key. This check makes sure | 
|  | * that the btf matches the attr used during map_create. | 
|  | */ | 
|  | if (BTF_INT_BITS(int_data) != 32 || BTF_INT_OFFSET(int_data)) | 
|  | return -EINVAL; | 
|  |  | 
|  | return 0; | 
|  | } | 
|  |  | 
|  | static int array_map_mmap(struct bpf_map *map, struct vm_area_struct *vma) | 
|  | { | 
|  | struct bpf_array *array = container_of(map, struct bpf_array, map); | 
|  | pgoff_t pgoff = PAGE_ALIGN(sizeof(*array)) >> PAGE_SHIFT; | 
|  |  | 
|  | if (!(map->map_flags & BPF_F_MMAPABLE)) | 
|  | return -EINVAL; | 
|  |  | 
|  | if (vma->vm_pgoff * PAGE_SIZE + (vma->vm_end - vma->vm_start) > | 
|  | PAGE_ALIGN((u64)array->map.max_entries * array->elem_size)) | 
|  | return -EINVAL; | 
|  |  | 
|  | return remap_vmalloc_range(vma, array_map_vmalloc_addr(array), | 
|  | vma->vm_pgoff + pgoff); | 
|  | } | 
|  |  | 
|  | static bool array_map_meta_equal(const struct bpf_map *meta0, | 
|  | const struct bpf_map *meta1) | 
|  | { | 
|  | if (!bpf_map_meta_equal(meta0, meta1)) | 
|  | return false; | 
|  | return meta0->map_flags & BPF_F_INNER_MAP ? true : | 
|  | meta0->max_entries == meta1->max_entries; | 
|  | } | 
|  |  | 
|  | struct bpf_iter_seq_array_map_info { | 
|  | struct bpf_map *map; | 
|  | void *percpu_value_buf; | 
|  | u32 index; | 
|  | }; | 
|  |  | 
|  | static void *bpf_array_map_seq_start(struct seq_file *seq, loff_t *pos) | 
|  | { | 
|  | struct bpf_iter_seq_array_map_info *info = seq->private; | 
|  | struct bpf_map *map = info->map; | 
|  | struct bpf_array *array; | 
|  | u32 index; | 
|  |  | 
|  | if (info->index >= map->max_entries) | 
|  | return NULL; | 
|  |  | 
|  | if (*pos == 0) | 
|  | ++*pos; | 
|  | array = container_of(map, struct bpf_array, map); | 
|  | index = info->index & array->index_mask; | 
|  | if (info->percpu_value_buf) | 
|  | return (void *)(uintptr_t)array->pptrs[index]; | 
|  | return array_map_elem_ptr(array, index); | 
|  | } | 
|  |  | 
|  | static void *bpf_array_map_seq_next(struct seq_file *seq, void *v, loff_t *pos) | 
|  | { | 
|  | struct bpf_iter_seq_array_map_info *info = seq->private; | 
|  | struct bpf_map *map = info->map; | 
|  | struct bpf_array *array; | 
|  | u32 index; | 
|  |  | 
|  | ++*pos; | 
|  | ++info->index; | 
|  | if (info->index >= map->max_entries) | 
|  | return NULL; | 
|  |  | 
|  | array = container_of(map, struct bpf_array, map); | 
|  | index = info->index & array->index_mask; | 
|  | if (info->percpu_value_buf) | 
|  | return (void *)(uintptr_t)array->pptrs[index]; | 
|  | return array_map_elem_ptr(array, index); | 
|  | } | 
|  |  | 
|  | static int __bpf_array_map_seq_show(struct seq_file *seq, void *v) | 
|  | { | 
|  | struct bpf_iter_seq_array_map_info *info = seq->private; | 
|  | struct bpf_iter__bpf_map_elem ctx = {}; | 
|  | struct bpf_map *map = info->map; | 
|  | struct bpf_array *array = container_of(map, struct bpf_array, map); | 
|  | struct bpf_iter_meta meta; | 
|  | struct bpf_prog *prog; | 
|  | int off = 0, cpu = 0; | 
|  | void __percpu *pptr; | 
|  | u32 size; | 
|  |  | 
|  | meta.seq = seq; | 
|  | prog = bpf_iter_get_info(&meta, v == NULL); | 
|  | if (!prog) | 
|  | return 0; | 
|  |  | 
|  | ctx.meta = &meta; | 
|  | ctx.map = info->map; | 
|  | if (v) { | 
|  | ctx.key = &info->index; | 
|  |  | 
|  | if (!info->percpu_value_buf) { | 
|  | ctx.value = v; | 
|  | } else { | 
|  | pptr = (void __percpu *)(uintptr_t)v; | 
|  | size = array->elem_size; | 
|  | for_each_possible_cpu(cpu) { | 
|  | copy_map_value_long(map, info->percpu_value_buf + off, | 
|  | per_cpu_ptr(pptr, cpu)); | 
|  | check_and_init_map_value(map, info->percpu_value_buf + off); | 
|  | off += size; | 
|  | } | 
|  | ctx.value = info->percpu_value_buf; | 
|  | } | 
|  | } | 
|  |  | 
|  | return bpf_iter_run_prog(prog, &ctx); | 
|  | } | 
|  |  | 
|  | static int bpf_array_map_seq_show(struct seq_file *seq, void *v) | 
|  | { | 
|  | return __bpf_array_map_seq_show(seq, v); | 
|  | } | 
|  |  | 
|  | static void bpf_array_map_seq_stop(struct seq_file *seq, void *v) | 
|  | { | 
|  | if (!v) | 
|  | (void)__bpf_array_map_seq_show(seq, NULL); | 
|  | } | 
|  |  | 
|  | static int bpf_iter_init_array_map(void *priv_data, | 
|  | struct bpf_iter_aux_info *aux) | 
|  | { | 
|  | struct bpf_iter_seq_array_map_info *seq_info = priv_data; | 
|  | struct bpf_map *map = aux->map; | 
|  | struct bpf_array *array = container_of(map, struct bpf_array, map); | 
|  | void *value_buf; | 
|  | u32 buf_size; | 
|  |  | 
|  | if (map->map_type == BPF_MAP_TYPE_PERCPU_ARRAY) { | 
|  | buf_size = array->elem_size * num_possible_cpus(); | 
|  | value_buf = kmalloc(buf_size, GFP_USER | __GFP_NOWARN); | 
|  | if (!value_buf) | 
|  | return -ENOMEM; | 
|  |  | 
|  | seq_info->percpu_value_buf = value_buf; | 
|  | } | 
|  |  | 
|  | /* bpf_iter_attach_map() acquires a map uref, and the uref may be | 
|  | * released before or in the middle of iterating map elements, so | 
|  | * acquire an extra map uref for iterator. | 
|  | */ | 
|  | bpf_map_inc_with_uref(map); | 
|  | seq_info->map = map; | 
|  | return 0; | 
|  | } | 
|  |  | 
|  | static void bpf_iter_fini_array_map(void *priv_data) | 
|  | { | 
|  | struct bpf_iter_seq_array_map_info *seq_info = priv_data; | 
|  |  | 
|  | bpf_map_put_with_uref(seq_info->map); | 
|  | kfree(seq_info->percpu_value_buf); | 
|  | } | 
|  |  | 
|  | static const struct seq_operations bpf_array_map_seq_ops = { | 
|  | .start	= bpf_array_map_seq_start, | 
|  | .next	= bpf_array_map_seq_next, | 
|  | .stop	= bpf_array_map_seq_stop, | 
|  | .show	= bpf_array_map_seq_show, | 
|  | }; | 
|  |  | 
|  | static const struct bpf_iter_seq_info iter_seq_info = { | 
|  | .seq_ops		= &bpf_array_map_seq_ops, | 
|  | .init_seq_private	= bpf_iter_init_array_map, | 
|  | .fini_seq_private	= bpf_iter_fini_array_map, | 
|  | .seq_priv_size		= sizeof(struct bpf_iter_seq_array_map_info), | 
|  | }; | 
|  |  | 
|  | static long bpf_for_each_array_elem(struct bpf_map *map, bpf_callback_t callback_fn, | 
|  | void *callback_ctx, u64 flags) | 
|  | { | 
|  | u32 i, key, num_elems = 0; | 
|  | struct bpf_array *array; | 
|  | bool is_percpu; | 
|  | u64 ret = 0; | 
|  | void *val; | 
|  |  | 
|  | cant_migrate(); | 
|  |  | 
|  | if (flags != 0) | 
|  | return -EINVAL; | 
|  |  | 
|  | is_percpu = map->map_type == BPF_MAP_TYPE_PERCPU_ARRAY; | 
|  | array = container_of(map, struct bpf_array, map); | 
|  | for (i = 0; i < map->max_entries; i++) { | 
|  | if (is_percpu) | 
|  | val = this_cpu_ptr(array->pptrs[i]); | 
|  | else | 
|  | val = array_map_elem_ptr(array, i); | 
|  | num_elems++; | 
|  | key = i; | 
|  | ret = callback_fn((u64)(long)map, (u64)(long)&key, | 
|  | (u64)(long)val, (u64)(long)callback_ctx, 0); | 
|  | /* return value: 0 - continue, 1 - stop and return */ | 
|  | if (ret) | 
|  | break; | 
|  | } | 
|  |  | 
|  | return num_elems; | 
|  | } | 
|  |  | 
|  | static u64 array_map_mem_usage(const struct bpf_map *map) | 
|  | { | 
|  | struct bpf_array *array = container_of(map, struct bpf_array, map); | 
|  | bool percpu = map->map_type == BPF_MAP_TYPE_PERCPU_ARRAY; | 
|  | u32 elem_size = array->elem_size; | 
|  | u64 entries = map->max_entries; | 
|  | u64 usage = sizeof(*array); | 
|  |  | 
|  | if (percpu) { | 
|  | usage += entries * sizeof(void *); | 
|  | usage += entries * elem_size * num_possible_cpus(); | 
|  | } else { | 
|  | if (map->map_flags & BPF_F_MMAPABLE) { | 
|  | usage = PAGE_ALIGN(usage); | 
|  | usage += PAGE_ALIGN(entries * elem_size); | 
|  | } else { | 
|  | usage += entries * elem_size; | 
|  | } | 
|  | } | 
|  | return usage; | 
|  | } | 
|  |  | 
|  | BTF_ID_LIST_SINGLE(array_map_btf_ids, struct, bpf_array) | 
|  | const struct bpf_map_ops array_map_ops = { | 
|  | .map_meta_equal = array_map_meta_equal, | 
|  | .map_alloc_check = array_map_alloc_check, | 
|  | .map_alloc = array_map_alloc, | 
|  | .map_free = array_map_free, | 
|  | .map_get_next_key = array_map_get_next_key, | 
|  | .map_release_uref = array_map_free_timers_wq, | 
|  | .map_lookup_elem = array_map_lookup_elem, | 
|  | .map_update_elem = array_map_update_elem, | 
|  | .map_delete_elem = array_map_delete_elem, | 
|  | .map_gen_lookup = array_map_gen_lookup, | 
|  | .map_direct_value_addr = array_map_direct_value_addr, | 
|  | .map_direct_value_meta = array_map_direct_value_meta, | 
|  | .map_mmap = array_map_mmap, | 
|  | .map_seq_show_elem = array_map_seq_show_elem, | 
|  | .map_check_btf = array_map_check_btf, | 
|  | .map_lookup_batch = generic_map_lookup_batch, | 
|  | .map_update_batch = generic_map_update_batch, | 
|  | .map_set_for_each_callback_args = map_set_for_each_callback_args, | 
|  | .map_for_each_callback = bpf_for_each_array_elem, | 
|  | .map_mem_usage = array_map_mem_usage, | 
|  | .map_btf_id = &array_map_btf_ids[0], | 
|  | .iter_seq_info = &iter_seq_info, | 
|  | }; | 
|  |  | 
|  | const struct bpf_map_ops percpu_array_map_ops = { | 
|  | .map_meta_equal = bpf_map_meta_equal, | 
|  | .map_alloc_check = array_map_alloc_check, | 
|  | .map_alloc = array_map_alloc, | 
|  | .map_free = array_map_free, | 
|  | .map_get_next_key = array_map_get_next_key, | 
|  | .map_lookup_elem = percpu_array_map_lookup_elem, | 
|  | .map_gen_lookup = percpu_array_map_gen_lookup, | 
|  | .map_update_elem = array_map_update_elem, | 
|  | .map_delete_elem = array_map_delete_elem, | 
|  | .map_lookup_percpu_elem = percpu_array_map_lookup_percpu_elem, | 
|  | .map_seq_show_elem = percpu_array_map_seq_show_elem, | 
|  | .map_check_btf = array_map_check_btf, | 
|  | .map_lookup_batch = generic_map_lookup_batch, | 
|  | .map_update_batch = generic_map_update_batch, | 
|  | .map_set_for_each_callback_args = map_set_for_each_callback_args, | 
|  | .map_for_each_callback = bpf_for_each_array_elem, | 
|  | .map_mem_usage = array_map_mem_usage, | 
|  | .map_btf_id = &array_map_btf_ids[0], | 
|  | .iter_seq_info = &iter_seq_info, | 
|  | }; | 
|  |  | 
|  | static int fd_array_map_alloc_check(union bpf_attr *attr) | 
|  | { | 
|  | /* only file descriptors can be stored in this type of map */ | 
|  | if (attr->value_size != sizeof(u32)) | 
|  | return -EINVAL; | 
|  | /* Program read-only/write-only not supported for special maps yet. */ | 
|  | if (attr->map_flags & (BPF_F_RDONLY_PROG | BPF_F_WRONLY_PROG)) | 
|  | return -EINVAL; | 
|  | return array_map_alloc_check(attr); | 
|  | } | 
|  |  | 
|  | static void fd_array_map_free(struct bpf_map *map) | 
|  | { | 
|  | struct bpf_array *array = container_of(map, struct bpf_array, map); | 
|  | int i; | 
|  |  | 
|  | /* make sure it's empty */ | 
|  | for (i = 0; i < array->map.max_entries; i++) | 
|  | BUG_ON(array->ptrs[i] != NULL); | 
|  |  | 
|  | bpf_map_area_free(array); | 
|  | } | 
|  |  | 
|  | static void *fd_array_map_lookup_elem(struct bpf_map *map, void *key) | 
|  | { | 
|  | return ERR_PTR(-EOPNOTSUPP); | 
|  | } | 
|  |  | 
|  | /* only called from syscall */ | 
|  | int bpf_fd_array_map_lookup_elem(struct bpf_map *map, void *key, u32 *value) | 
|  | { | 
|  | void **elem, *ptr; | 
|  | int ret =  0; | 
|  |  | 
|  | if (!map->ops->map_fd_sys_lookup_elem) | 
|  | return -ENOTSUPP; | 
|  |  | 
|  | rcu_read_lock(); | 
|  | elem = array_map_lookup_elem(map, key); | 
|  | if (elem && (ptr = READ_ONCE(*elem))) | 
|  | *value = map->ops->map_fd_sys_lookup_elem(ptr); | 
|  | else | 
|  | ret = -ENOENT; | 
|  | rcu_read_unlock(); | 
|  |  | 
|  | return ret; | 
|  | } | 
|  |  | 
|  | /* only called from syscall */ | 
|  | int bpf_fd_array_map_update_elem(struct bpf_map *map, struct file *map_file, | 
|  | void *key, void *value, u64 map_flags) | 
|  | { | 
|  | struct bpf_array *array = container_of(map, struct bpf_array, map); | 
|  | void *new_ptr, *old_ptr; | 
|  | u32 index = *(u32 *)key, ufd; | 
|  |  | 
|  | if (map_flags != BPF_ANY) | 
|  | return -EINVAL; | 
|  |  | 
|  | if (index >= array->map.max_entries) | 
|  | return -E2BIG; | 
|  |  | 
|  | ufd = *(u32 *)value; | 
|  | new_ptr = map->ops->map_fd_get_ptr(map, map_file, ufd); | 
|  | if (IS_ERR(new_ptr)) | 
|  | return PTR_ERR(new_ptr); | 
|  |  | 
|  | if (map->ops->map_poke_run) { | 
|  | mutex_lock(&array->aux->poke_mutex); | 
|  | old_ptr = xchg(array->ptrs + index, new_ptr); | 
|  | map->ops->map_poke_run(map, index, old_ptr, new_ptr); | 
|  | mutex_unlock(&array->aux->poke_mutex); | 
|  | } else { | 
|  | old_ptr = xchg(array->ptrs + index, new_ptr); | 
|  | } | 
|  |  | 
|  | if (old_ptr) | 
|  | map->ops->map_fd_put_ptr(map, old_ptr, true); | 
|  | return 0; | 
|  | } | 
|  |  | 
|  | static long __fd_array_map_delete_elem(struct bpf_map *map, void *key, bool need_defer) | 
|  | { | 
|  | struct bpf_array *array = container_of(map, struct bpf_array, map); | 
|  | void *old_ptr; | 
|  | u32 index = *(u32 *)key; | 
|  |  | 
|  | if (index >= array->map.max_entries) | 
|  | return -E2BIG; | 
|  |  | 
|  | if (map->ops->map_poke_run) { | 
|  | mutex_lock(&array->aux->poke_mutex); | 
|  | old_ptr = xchg(array->ptrs + index, NULL); | 
|  | map->ops->map_poke_run(map, index, old_ptr, NULL); | 
|  | mutex_unlock(&array->aux->poke_mutex); | 
|  | } else { | 
|  | old_ptr = xchg(array->ptrs + index, NULL); | 
|  | } | 
|  |  | 
|  | if (old_ptr) { | 
|  | map->ops->map_fd_put_ptr(map, old_ptr, need_defer); | 
|  | return 0; | 
|  | } else { | 
|  | return -ENOENT; | 
|  | } | 
|  | } | 
|  |  | 
|  | static long fd_array_map_delete_elem(struct bpf_map *map, void *key) | 
|  | { | 
|  | return __fd_array_map_delete_elem(map, key, true); | 
|  | } | 
|  |  | 
|  | static void *prog_fd_array_get_ptr(struct bpf_map *map, | 
|  | struct file *map_file, int fd) | 
|  | { | 
|  | struct bpf_prog *prog = bpf_prog_get(fd); | 
|  | bool is_extended; | 
|  |  | 
|  | if (IS_ERR(prog)) | 
|  | return prog; | 
|  |  | 
|  | if (prog->type == BPF_PROG_TYPE_EXT || | 
|  | !bpf_prog_map_compatible(map, prog)) { | 
|  | bpf_prog_put(prog); | 
|  | return ERR_PTR(-EINVAL); | 
|  | } | 
|  |  | 
|  | mutex_lock(&prog->aux->ext_mutex); | 
|  | is_extended = prog->aux->is_extended; | 
|  | if (!is_extended) | 
|  | prog->aux->prog_array_member_cnt++; | 
|  | mutex_unlock(&prog->aux->ext_mutex); | 
|  | if (is_extended) { | 
|  | /* Extended prog can not be tail callee. It's to prevent a | 
|  | * potential infinite loop like: | 
|  | * tail callee prog entry -> tail callee prog subprog -> | 
|  | * freplace prog entry --tailcall-> tail callee prog entry. | 
|  | */ | 
|  | bpf_prog_put(prog); | 
|  | return ERR_PTR(-EBUSY); | 
|  | } | 
|  |  | 
|  | return prog; | 
|  | } | 
|  |  | 
|  | static void prog_fd_array_put_ptr(struct bpf_map *map, void *ptr, bool need_defer) | 
|  | { | 
|  | struct bpf_prog *prog = ptr; | 
|  |  | 
|  | mutex_lock(&prog->aux->ext_mutex); | 
|  | prog->aux->prog_array_member_cnt--; | 
|  | mutex_unlock(&prog->aux->ext_mutex); | 
|  | /* bpf_prog is freed after one RCU or tasks trace grace period */ | 
|  | bpf_prog_put(prog); | 
|  | } | 
|  |  | 
|  | static u32 prog_fd_array_sys_lookup_elem(void *ptr) | 
|  | { | 
|  | return ((struct bpf_prog *)ptr)->aux->id; | 
|  | } | 
|  |  | 
|  | /* decrement refcnt of all bpf_progs that are stored in this map */ | 
|  | static void bpf_fd_array_map_clear(struct bpf_map *map, bool need_defer) | 
|  | { | 
|  | struct bpf_array *array = container_of(map, struct bpf_array, map); | 
|  | int i; | 
|  |  | 
|  | for (i = 0; i < array->map.max_entries; i++) | 
|  | __fd_array_map_delete_elem(map, &i, need_defer); | 
|  | } | 
|  |  | 
|  | static void prog_array_map_seq_show_elem(struct bpf_map *map, void *key, | 
|  | struct seq_file *m) | 
|  | { | 
|  | void **elem, *ptr; | 
|  | u32 prog_id; | 
|  |  | 
|  | rcu_read_lock(); | 
|  |  | 
|  | elem = array_map_lookup_elem(map, key); | 
|  | if (elem) { | 
|  | ptr = READ_ONCE(*elem); | 
|  | if (ptr) { | 
|  | seq_printf(m, "%u: ", *(u32 *)key); | 
|  | prog_id = prog_fd_array_sys_lookup_elem(ptr); | 
|  | btf_type_seq_show(map->btf, map->btf_value_type_id, | 
|  | &prog_id, m); | 
|  | seq_putc(m, '\n'); | 
|  | } | 
|  | } | 
|  |  | 
|  | rcu_read_unlock(); | 
|  | } | 
|  |  | 
|  | struct prog_poke_elem { | 
|  | struct list_head list; | 
|  | struct bpf_prog_aux *aux; | 
|  | }; | 
|  |  | 
|  | static int prog_array_map_poke_track(struct bpf_map *map, | 
|  | struct bpf_prog_aux *prog_aux) | 
|  | { | 
|  | struct prog_poke_elem *elem; | 
|  | struct bpf_array_aux *aux; | 
|  | int ret = 0; | 
|  |  | 
|  | aux = container_of(map, struct bpf_array, map)->aux; | 
|  | mutex_lock(&aux->poke_mutex); | 
|  | list_for_each_entry(elem, &aux->poke_progs, list) { | 
|  | if (elem->aux == prog_aux) | 
|  | goto out; | 
|  | } | 
|  |  | 
|  | elem = kmalloc(sizeof(*elem), GFP_KERNEL); | 
|  | if (!elem) { | 
|  | ret = -ENOMEM; | 
|  | goto out; | 
|  | } | 
|  |  | 
|  | INIT_LIST_HEAD(&elem->list); | 
|  | /* We must track the program's aux info at this point in time | 
|  | * since the program pointer itself may not be stable yet, see | 
|  | * also comment in prog_array_map_poke_run(). | 
|  | */ | 
|  | elem->aux = prog_aux; | 
|  |  | 
|  | list_add_tail(&elem->list, &aux->poke_progs); | 
|  | out: | 
|  | mutex_unlock(&aux->poke_mutex); | 
|  | return ret; | 
|  | } | 
|  |  | 
|  | static void prog_array_map_poke_untrack(struct bpf_map *map, | 
|  | struct bpf_prog_aux *prog_aux) | 
|  | { | 
|  | struct prog_poke_elem *elem, *tmp; | 
|  | struct bpf_array_aux *aux; | 
|  |  | 
|  | aux = container_of(map, struct bpf_array, map)->aux; | 
|  | mutex_lock(&aux->poke_mutex); | 
|  | list_for_each_entry_safe(elem, tmp, &aux->poke_progs, list) { | 
|  | if (elem->aux == prog_aux) { | 
|  | list_del_init(&elem->list); | 
|  | kfree(elem); | 
|  | break; | 
|  | } | 
|  | } | 
|  | mutex_unlock(&aux->poke_mutex); | 
|  | } | 
|  |  | 
|  | void __weak bpf_arch_poke_desc_update(struct bpf_jit_poke_descriptor *poke, | 
|  | struct bpf_prog *new, struct bpf_prog *old) | 
|  | { | 
|  | WARN_ON_ONCE(1); | 
|  | } | 
|  |  | 
|  | static void prog_array_map_poke_run(struct bpf_map *map, u32 key, | 
|  | struct bpf_prog *old, | 
|  | struct bpf_prog *new) | 
|  | { | 
|  | struct prog_poke_elem *elem; | 
|  | struct bpf_array_aux *aux; | 
|  |  | 
|  | aux = container_of(map, struct bpf_array, map)->aux; | 
|  | WARN_ON_ONCE(!mutex_is_locked(&aux->poke_mutex)); | 
|  |  | 
|  | list_for_each_entry(elem, &aux->poke_progs, list) { | 
|  | struct bpf_jit_poke_descriptor *poke; | 
|  | int i; | 
|  |  | 
|  | for (i = 0; i < elem->aux->size_poke_tab; i++) { | 
|  | poke = &elem->aux->poke_tab[i]; | 
|  |  | 
|  | /* Few things to be aware of: | 
|  | * | 
|  | * 1) We can only ever access aux in this context, but | 
|  | *    not aux->prog since it might not be stable yet and | 
|  | *    there could be danger of use after free otherwise. | 
|  | * 2) Initially when we start tracking aux, the program | 
|  | *    is not JITed yet and also does not have a kallsyms | 
|  | *    entry. We skip these as poke->tailcall_target_stable | 
|  | *    is not active yet. The JIT will do the final fixup | 
|  | *    before setting it stable. The various | 
|  | *    poke->tailcall_target_stable are successively | 
|  | *    activated, so tail call updates can arrive from here | 
|  | *    while JIT is still finishing its final fixup for | 
|  | *    non-activated poke entries. | 
|  | * 3) Also programs reaching refcount of zero while patching | 
|  | *    is in progress is okay since we're protected under | 
|  | *    poke_mutex and untrack the programs before the JIT | 
|  | *    buffer is freed. | 
|  | */ | 
|  | if (!READ_ONCE(poke->tailcall_target_stable)) | 
|  | continue; | 
|  | if (poke->reason != BPF_POKE_REASON_TAIL_CALL) | 
|  | continue; | 
|  | if (poke->tail_call.map != map || | 
|  | poke->tail_call.key != key) | 
|  | continue; | 
|  |  | 
|  | bpf_arch_poke_desc_update(poke, new, old); | 
|  | } | 
|  | } | 
|  | } | 
|  |  | 
|  | static void prog_array_map_clear_deferred(struct work_struct *work) | 
|  | { | 
|  | struct bpf_map *map = container_of(work, struct bpf_array_aux, | 
|  | work)->map; | 
|  | bpf_fd_array_map_clear(map, true); | 
|  | bpf_map_put(map); | 
|  | } | 
|  |  | 
|  | static void prog_array_map_clear(struct bpf_map *map) | 
|  | { | 
|  | struct bpf_array_aux *aux = container_of(map, struct bpf_array, | 
|  | map)->aux; | 
|  | bpf_map_inc(map); | 
|  | schedule_work(&aux->work); | 
|  | } | 
|  |  | 
|  | static struct bpf_map *prog_array_map_alloc(union bpf_attr *attr) | 
|  | { | 
|  | struct bpf_array_aux *aux; | 
|  | struct bpf_map *map; | 
|  |  | 
|  | aux = kzalloc(sizeof(*aux), GFP_KERNEL_ACCOUNT); | 
|  | if (!aux) | 
|  | return ERR_PTR(-ENOMEM); | 
|  |  | 
|  | INIT_WORK(&aux->work, prog_array_map_clear_deferred); | 
|  | INIT_LIST_HEAD(&aux->poke_progs); | 
|  | mutex_init(&aux->poke_mutex); | 
|  |  | 
|  | map = array_map_alloc(attr); | 
|  | if (IS_ERR(map)) { | 
|  | kfree(aux); | 
|  | return map; | 
|  | } | 
|  |  | 
|  | container_of(map, struct bpf_array, map)->aux = aux; | 
|  | aux->map = map; | 
|  |  | 
|  | return map; | 
|  | } | 
|  |  | 
|  | static void prog_array_map_free(struct bpf_map *map) | 
|  | { | 
|  | struct prog_poke_elem *elem, *tmp; | 
|  | struct bpf_array_aux *aux; | 
|  |  | 
|  | aux = container_of(map, struct bpf_array, map)->aux; | 
|  | list_for_each_entry_safe(elem, tmp, &aux->poke_progs, list) { | 
|  | list_del_init(&elem->list); | 
|  | kfree(elem); | 
|  | } | 
|  | kfree(aux); | 
|  | fd_array_map_free(map); | 
|  | } | 
|  |  | 
|  | /* prog_array->aux->{type,jited} is a runtime binding. | 
|  | * Doing static check alone in the verifier is not enough. | 
|  | * Thus, prog_array_map cannot be used as an inner_map | 
|  | * and map_meta_equal is not implemented. | 
|  | */ | 
|  | const struct bpf_map_ops prog_array_map_ops = { | 
|  | .map_alloc_check = fd_array_map_alloc_check, | 
|  | .map_alloc = prog_array_map_alloc, | 
|  | .map_free = prog_array_map_free, | 
|  | .map_poke_track = prog_array_map_poke_track, | 
|  | .map_poke_untrack = prog_array_map_poke_untrack, | 
|  | .map_poke_run = prog_array_map_poke_run, | 
|  | .map_get_next_key = array_map_get_next_key, | 
|  | .map_lookup_elem = fd_array_map_lookup_elem, | 
|  | .map_delete_elem = fd_array_map_delete_elem, | 
|  | .map_fd_get_ptr = prog_fd_array_get_ptr, | 
|  | .map_fd_put_ptr = prog_fd_array_put_ptr, | 
|  | .map_fd_sys_lookup_elem = prog_fd_array_sys_lookup_elem, | 
|  | .map_release_uref = prog_array_map_clear, | 
|  | .map_seq_show_elem = prog_array_map_seq_show_elem, | 
|  | .map_mem_usage = array_map_mem_usage, | 
|  | .map_btf_id = &array_map_btf_ids[0], | 
|  | }; | 
|  |  | 
|  | static struct bpf_event_entry *bpf_event_entry_gen(struct file *perf_file, | 
|  | struct file *map_file) | 
|  | { | 
|  | struct bpf_event_entry *ee; | 
|  |  | 
|  | ee = kzalloc(sizeof(*ee), GFP_KERNEL); | 
|  | if (ee) { | 
|  | ee->event = perf_file->private_data; | 
|  | ee->perf_file = perf_file; | 
|  | ee->map_file = map_file; | 
|  | } | 
|  |  | 
|  | return ee; | 
|  | } | 
|  |  | 
|  | static void __bpf_event_entry_free(struct rcu_head *rcu) | 
|  | { | 
|  | struct bpf_event_entry *ee; | 
|  |  | 
|  | ee = container_of(rcu, struct bpf_event_entry, rcu); | 
|  | fput(ee->perf_file); | 
|  | kfree(ee); | 
|  | } | 
|  |  | 
|  | static void bpf_event_entry_free_rcu(struct bpf_event_entry *ee) | 
|  | { | 
|  | call_rcu(&ee->rcu, __bpf_event_entry_free); | 
|  | } | 
|  |  | 
|  | static void *perf_event_fd_array_get_ptr(struct bpf_map *map, | 
|  | struct file *map_file, int fd) | 
|  | { | 
|  | struct bpf_event_entry *ee; | 
|  | struct perf_event *event; | 
|  | struct file *perf_file; | 
|  | u64 value; | 
|  |  | 
|  | perf_file = perf_event_get(fd); | 
|  | if (IS_ERR(perf_file)) | 
|  | return perf_file; | 
|  |  | 
|  | ee = ERR_PTR(-EOPNOTSUPP); | 
|  | event = perf_file->private_data; | 
|  | if (perf_event_read_local(event, &value, NULL, NULL) == -EOPNOTSUPP) | 
|  | goto err_out; | 
|  |  | 
|  | ee = bpf_event_entry_gen(perf_file, map_file); | 
|  | if (ee) | 
|  | return ee; | 
|  | ee = ERR_PTR(-ENOMEM); | 
|  | err_out: | 
|  | fput(perf_file); | 
|  | return ee; | 
|  | } | 
|  |  | 
|  | static void perf_event_fd_array_put_ptr(struct bpf_map *map, void *ptr, bool need_defer) | 
|  | { | 
|  | /* bpf_perf_event is freed after one RCU grace period */ | 
|  | bpf_event_entry_free_rcu(ptr); | 
|  | } | 
|  |  | 
|  | static void perf_event_fd_array_release(struct bpf_map *map, | 
|  | struct file *map_file) | 
|  | { | 
|  | struct bpf_array *array = container_of(map, struct bpf_array, map); | 
|  | struct bpf_event_entry *ee; | 
|  | int i; | 
|  |  | 
|  | if (map->map_flags & BPF_F_PRESERVE_ELEMS) | 
|  | return; | 
|  |  | 
|  | rcu_read_lock(); | 
|  | for (i = 0; i < array->map.max_entries; i++) { | 
|  | ee = READ_ONCE(array->ptrs[i]); | 
|  | if (ee && ee->map_file == map_file) | 
|  | __fd_array_map_delete_elem(map, &i, true); | 
|  | } | 
|  | rcu_read_unlock(); | 
|  | } | 
|  |  | 
|  | static void perf_event_fd_array_map_free(struct bpf_map *map) | 
|  | { | 
|  | if (map->map_flags & BPF_F_PRESERVE_ELEMS) | 
|  | bpf_fd_array_map_clear(map, false); | 
|  | fd_array_map_free(map); | 
|  | } | 
|  |  | 
|  | const struct bpf_map_ops perf_event_array_map_ops = { | 
|  | .map_meta_equal = bpf_map_meta_equal, | 
|  | .map_alloc_check = fd_array_map_alloc_check, | 
|  | .map_alloc = array_map_alloc, | 
|  | .map_free = perf_event_fd_array_map_free, | 
|  | .map_get_next_key = array_map_get_next_key, | 
|  | .map_lookup_elem = fd_array_map_lookup_elem, | 
|  | .map_delete_elem = fd_array_map_delete_elem, | 
|  | .map_fd_get_ptr = perf_event_fd_array_get_ptr, | 
|  | .map_fd_put_ptr = perf_event_fd_array_put_ptr, | 
|  | .map_release = perf_event_fd_array_release, | 
|  | .map_check_btf = map_check_no_btf, | 
|  | .map_mem_usage = array_map_mem_usage, | 
|  | .map_btf_id = &array_map_btf_ids[0], | 
|  | }; | 
|  |  | 
|  | #ifdef CONFIG_CGROUPS | 
|  | static void *cgroup_fd_array_get_ptr(struct bpf_map *map, | 
|  | struct file *map_file /* not used */, | 
|  | int fd) | 
|  | { | 
|  | return cgroup_get_from_fd(fd); | 
|  | } | 
|  |  | 
|  | static void cgroup_fd_array_put_ptr(struct bpf_map *map, void *ptr, bool need_defer) | 
|  | { | 
|  | /* cgroup_put free cgrp after a rcu grace period */ | 
|  | cgroup_put(ptr); | 
|  | } | 
|  |  | 
|  | static void cgroup_fd_array_free(struct bpf_map *map) | 
|  | { | 
|  | bpf_fd_array_map_clear(map, false); | 
|  | fd_array_map_free(map); | 
|  | } | 
|  |  | 
|  | const struct bpf_map_ops cgroup_array_map_ops = { | 
|  | .map_meta_equal = bpf_map_meta_equal, | 
|  | .map_alloc_check = fd_array_map_alloc_check, | 
|  | .map_alloc = array_map_alloc, | 
|  | .map_free = cgroup_fd_array_free, | 
|  | .map_get_next_key = array_map_get_next_key, | 
|  | .map_lookup_elem = fd_array_map_lookup_elem, | 
|  | .map_delete_elem = fd_array_map_delete_elem, | 
|  | .map_fd_get_ptr = cgroup_fd_array_get_ptr, | 
|  | .map_fd_put_ptr = cgroup_fd_array_put_ptr, | 
|  | .map_check_btf = map_check_no_btf, | 
|  | .map_mem_usage = array_map_mem_usage, | 
|  | .map_btf_id = &array_map_btf_ids[0], | 
|  | }; | 
|  | #endif | 
|  |  | 
|  | static struct bpf_map *array_of_map_alloc(union bpf_attr *attr) | 
|  | { | 
|  | struct bpf_map *map, *inner_map_meta; | 
|  |  | 
|  | inner_map_meta = bpf_map_meta_alloc(attr->inner_map_fd); | 
|  | if (IS_ERR(inner_map_meta)) | 
|  | return inner_map_meta; | 
|  |  | 
|  | map = array_map_alloc(attr); | 
|  | if (IS_ERR(map)) { | 
|  | bpf_map_meta_free(inner_map_meta); | 
|  | return map; | 
|  | } | 
|  |  | 
|  | map->inner_map_meta = inner_map_meta; | 
|  |  | 
|  | return map; | 
|  | } | 
|  |  | 
|  | static void array_of_map_free(struct bpf_map *map) | 
|  | { | 
|  | /* map->inner_map_meta is only accessed by syscall which | 
|  | * is protected by fdget/fdput. | 
|  | */ | 
|  | bpf_map_meta_free(map->inner_map_meta); | 
|  | bpf_fd_array_map_clear(map, false); | 
|  | fd_array_map_free(map); | 
|  | } | 
|  |  | 
|  | static void *array_of_map_lookup_elem(struct bpf_map *map, void *key) | 
|  | { | 
|  | struct bpf_map **inner_map = array_map_lookup_elem(map, key); | 
|  |  | 
|  | if (!inner_map) | 
|  | return NULL; | 
|  |  | 
|  | return READ_ONCE(*inner_map); | 
|  | } | 
|  |  | 
|  | static int array_of_map_gen_lookup(struct bpf_map *map, | 
|  | struct bpf_insn *insn_buf) | 
|  | { | 
|  | struct bpf_array *array = container_of(map, struct bpf_array, map); | 
|  | u32 elem_size = array->elem_size; | 
|  | struct bpf_insn *insn = insn_buf; | 
|  | const int ret = BPF_REG_0; | 
|  | const int map_ptr = BPF_REG_1; | 
|  | const int index = BPF_REG_2; | 
|  |  | 
|  | *insn++ = BPF_ALU64_IMM(BPF_ADD, map_ptr, offsetof(struct bpf_array, value)); | 
|  | *insn++ = BPF_LDX_MEM(BPF_W, ret, index, 0); | 
|  | if (!map->bypass_spec_v1) { | 
|  | *insn++ = BPF_JMP_IMM(BPF_JGE, ret, map->max_entries, 6); | 
|  | *insn++ = BPF_ALU32_IMM(BPF_AND, ret, array->index_mask); | 
|  | } else { | 
|  | *insn++ = BPF_JMP_IMM(BPF_JGE, ret, map->max_entries, 5); | 
|  | } | 
|  | if (is_power_of_2(elem_size)) | 
|  | *insn++ = BPF_ALU64_IMM(BPF_LSH, ret, ilog2(elem_size)); | 
|  | else | 
|  | *insn++ = BPF_ALU64_IMM(BPF_MUL, ret, elem_size); | 
|  | *insn++ = BPF_ALU64_REG(BPF_ADD, ret, map_ptr); | 
|  | *insn++ = BPF_LDX_MEM(BPF_DW, ret, ret, 0); | 
|  | *insn++ = BPF_JMP_IMM(BPF_JEQ, ret, 0, 1); | 
|  | *insn++ = BPF_JMP_IMM(BPF_JA, 0, 0, 1); | 
|  | *insn++ = BPF_MOV64_IMM(ret, 0); | 
|  |  | 
|  | return insn - insn_buf; | 
|  | } | 
|  |  | 
|  | const struct bpf_map_ops array_of_maps_map_ops = { | 
|  | .map_alloc_check = fd_array_map_alloc_check, | 
|  | .map_alloc = array_of_map_alloc, | 
|  | .map_free = array_of_map_free, | 
|  | .map_get_next_key = array_map_get_next_key, | 
|  | .map_lookup_elem = array_of_map_lookup_elem, | 
|  | .map_delete_elem = fd_array_map_delete_elem, | 
|  | .map_fd_get_ptr = bpf_map_fd_get_ptr, | 
|  | .map_fd_put_ptr = bpf_map_fd_put_ptr, | 
|  | .map_fd_sys_lookup_elem = bpf_map_fd_sys_lookup_elem, | 
|  | .map_gen_lookup = array_of_map_gen_lookup, | 
|  | .map_lookup_batch = generic_map_lookup_batch, | 
|  | .map_update_batch = generic_map_update_batch, | 
|  | .map_check_btf = map_check_no_btf, | 
|  | .map_mem_usage = array_map_mem_usage, | 
|  | .map_btf_id = &array_map_btf_ids[0], | 
|  | }; |