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-rw-r--r--arch/x86/net/bpf_jit_comp.c9
-rw-r--r--include/linux/bpf.h15
-rw-r--r--include/linux/bpf_types.h1
-rw-r--r--include/linux/bpf_verifier.h2
-rw-r--r--include/uapi/linux/bpf.h21
-rw-r--r--kernel/bpf/Makefile2
-rw-r--r--kernel/bpf/bpf_insn_array.c286
-rw-r--r--kernel/bpf/syscall.c22
-rw-r--r--kernel/bpf/verifier.c45
-rw-r--r--tools/include/uapi/linux/bpf.h21
10 files changed, 423 insertions, 1 deletions
diff --git a/arch/x86/net/bpf_jit_comp.c b/arch/x86/net/bpf_jit_comp.c
index de5083cb1d37..91f92d65ae83 100644
--- a/arch/x86/net/bpf_jit_comp.c
+++ b/arch/x86/net/bpf_jit_comp.c
@@ -3827,6 +3827,15 @@ out_image:
jit_data->header = header;
jit_data->rw_header = rw_header;
}
+
+ /*
+ * The bpf_prog_update_insn_ptrs function expects addrs to
+ * point to the first byte of the jitted instruction (unlike
+ * the bpf_prog_fill_jited_linfo below, which, for historical
+ * reasons, expects to point to the next instruction)
+ */
+ bpf_prog_update_insn_ptrs(prog, addrs, image);
+
/*
* ctx.prog_offset is used when CFI preambles put code *before*
* the function. See emit_cfi(). For FineIBT specifically this code
diff --git a/include/linux/bpf.h b/include/linux/bpf.h
index a47d67db3be5..9d41a6affcef 100644
--- a/include/linux/bpf.h
+++ b/include/linux/bpf.h
@@ -3797,4 +3797,19 @@ int bpf_prog_get_file_line(struct bpf_prog *prog, unsigned long ip, const char *
const char **linep, int *nump);
struct bpf_prog *bpf_prog_find_from_stack(void);
+int bpf_insn_array_init(struct bpf_map *map, const struct bpf_prog *prog);
+int bpf_insn_array_ready(struct bpf_map *map);
+void bpf_insn_array_release(struct bpf_map *map);
+void bpf_insn_array_adjust(struct bpf_map *map, u32 off, u32 len);
+void bpf_insn_array_adjust_after_remove(struct bpf_map *map, u32 off, u32 len);
+
+#ifdef CONFIG_BPF_SYSCALL
+void bpf_prog_update_insn_ptrs(struct bpf_prog *prog, u32 *offsets, void *image);
+#else
+static inline void
+bpf_prog_update_insn_ptrs(struct bpf_prog *prog, u32 *offsets, void *image)
+{
+}
+#endif
+
#endif /* _LINUX_BPF_H */
diff --git a/include/linux/bpf_types.h b/include/linux/bpf_types.h
index fa78f49d4a9a..b13de31e163f 100644
--- a/include/linux/bpf_types.h
+++ b/include/linux/bpf_types.h
@@ -133,6 +133,7 @@ BPF_MAP_TYPE(BPF_MAP_TYPE_RINGBUF, ringbuf_map_ops)
BPF_MAP_TYPE(BPF_MAP_TYPE_BLOOM_FILTER, bloom_filter_map_ops)
BPF_MAP_TYPE(BPF_MAP_TYPE_USER_RINGBUF, user_ringbuf_map_ops)
BPF_MAP_TYPE(BPF_MAP_TYPE_ARENA, arena_map_ops)
+BPF_MAP_TYPE(BPF_MAP_TYPE_INSN_ARRAY, insn_array_map_ops)
BPF_LINK_TYPE(BPF_LINK_TYPE_RAW_TRACEPOINT, raw_tracepoint)
BPF_LINK_TYPE(BPF_LINK_TYPE_TRACING, tracing)
diff --git a/include/linux/bpf_verifier.h b/include/linux/bpf_verifier.h
index c6eb68b6389c..6b820d8d77af 100644
--- a/include/linux/bpf_verifier.h
+++ b/include/linux/bpf_verifier.h
@@ -754,8 +754,10 @@ struct bpf_verifier_env {
struct list_head free_list; /* list of struct bpf_verifier_state_list */
struct bpf_map *used_maps[MAX_USED_MAPS]; /* array of map's used by eBPF program */
struct btf_mod_pair used_btfs[MAX_USED_BTFS]; /* array of BTF's used by BPF program */
+ struct bpf_map *insn_array_maps[MAX_USED_MAPS]; /* array of INSN_ARRAY map's to be relocated */
u32 used_map_cnt; /* number of used maps */
u32 used_btf_cnt; /* number of used BTF objects */
+ u32 insn_array_map_cnt; /* number of used maps of type BPF_MAP_TYPE_INSN_ARRAY */
u32 id_gen; /* used to generate unique reg IDs */
u32 hidden_subprog_cnt; /* number of hidden subprogs */
int exception_callback_subprog;
diff --git a/include/uapi/linux/bpf.h b/include/uapi/linux/bpf.h
index 1d73f165394d..f5713f59ac10 100644
--- a/include/uapi/linux/bpf.h
+++ b/include/uapi/linux/bpf.h
@@ -1026,6 +1026,7 @@ enum bpf_map_type {
BPF_MAP_TYPE_USER_RINGBUF,
BPF_MAP_TYPE_CGRP_STORAGE,
BPF_MAP_TYPE_ARENA,
+ BPF_MAP_TYPE_INSN_ARRAY,
__MAX_BPF_MAP_TYPE
};
@@ -7649,4 +7650,24 @@ enum bpf_kfunc_flags {
BPF_F_PAD_ZEROS = (1ULL << 0),
};
+/*
+ * Values of a BPF_MAP_TYPE_INSN_ARRAY entry must be of this type.
+ *
+ * Before the map is used the orig_off field should point to an
+ * instruction inside the program being loaded. The other fields
+ * must be set to 0.
+ *
+ * After the program is loaded, the xlated_off will be adjusted
+ * by the verifier to point to the index of the original instruction
+ * in the xlated program. If the instruction is deleted, it will
+ * be set to (u32)-1. The jitted_off will be set to the corresponding
+ * offset in the jitted image of the program.
+ */
+struct bpf_insn_array_value {
+ __u32 orig_off;
+ __u32 xlated_off;
+ __u32 jitted_off;
+ __u32 :32;
+};
+
#endif /* _UAPI__LINUX_BPF_H__ */
diff --git a/kernel/bpf/Makefile b/kernel/bpf/Makefile
index 7fd0badfacb1..232cbc97434d 100644
--- a/kernel/bpf/Makefile
+++ b/kernel/bpf/Makefile
@@ -9,7 +9,7 @@ CFLAGS_core.o += -Wno-override-init $(cflags-nogcse-yy)
obj-$(CONFIG_BPF_SYSCALL) += syscall.o verifier.o inode.o helpers.o tnum.o log.o token.o liveness.o
obj-$(CONFIG_BPF_SYSCALL) += bpf_iter.o map_iter.o task_iter.o prog_iter.o link_iter.o
obj-$(CONFIG_BPF_SYSCALL) += hashtab.o arraymap.o percpu_freelist.o bpf_lru_list.o lpm_trie.o map_in_map.o bloom_filter.o
-obj-$(CONFIG_BPF_SYSCALL) += local_storage.o queue_stack_maps.o ringbuf.o
+obj-$(CONFIG_BPF_SYSCALL) += local_storage.o queue_stack_maps.o ringbuf.o bpf_insn_array.o
obj-$(CONFIG_BPF_SYSCALL) += bpf_local_storage.o bpf_task_storage.o
obj-${CONFIG_BPF_LSM} += bpf_inode_storage.o
obj-$(CONFIG_BPF_SYSCALL) += disasm.o mprog.o
diff --git a/kernel/bpf/bpf_insn_array.c b/kernel/bpf/bpf_insn_array.c
new file mode 100644
index 000000000000..2053fda377bb
--- /dev/null
+++ b/kernel/bpf/bpf_insn_array.c
@@ -0,0 +1,286 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/* Copyright (c) 2025 Isovalent */
+
+#include <linux/bpf.h>
+
+struct bpf_insn_array {
+ struct bpf_map map;
+ atomic_t used;
+ long *ips;
+ DECLARE_FLEX_ARRAY(struct bpf_insn_array_value, values);
+};
+
+#define cast_insn_array(MAP_PTR) \
+ container_of((MAP_PTR), struct bpf_insn_array, map)
+
+#define INSN_DELETED ((u32)-1)
+
+static inline u64 insn_array_alloc_size(u32 max_entries)
+{
+ const u64 base_size = sizeof(struct bpf_insn_array);
+ const u64 entry_size = sizeof(struct bpf_insn_array_value);
+
+ return base_size + max_entries * (entry_size + sizeof(long));
+}
+
+static int insn_array_alloc_check(union bpf_attr *attr)
+{
+ u32 value_size = sizeof(struct bpf_insn_array_value);
+
+ if (attr->max_entries == 0 || attr->key_size != 4 ||
+ attr->value_size != value_size || attr->map_flags != 0)
+ return -EINVAL;
+
+ return 0;
+}
+
+static void insn_array_free(struct bpf_map *map)
+{
+ struct bpf_insn_array *insn_array = cast_insn_array(map);
+
+ bpf_map_area_free(insn_array);
+}
+
+static struct bpf_map *insn_array_alloc(union bpf_attr *attr)
+{
+ u64 size = insn_array_alloc_size(attr->max_entries);
+ struct bpf_insn_array *insn_array;
+
+ insn_array = bpf_map_area_alloc(size, NUMA_NO_NODE);
+ if (!insn_array)
+ return ERR_PTR(-ENOMEM);
+
+ /* ips are allocated right after the insn_array->values[] array */
+ insn_array->ips = (void *)&insn_array->values[attr->max_entries];
+
+ bpf_map_init_from_attr(&insn_array->map, attr);
+
+ return &insn_array->map;
+}
+
+static void *insn_array_lookup_elem(struct bpf_map *map, void *key)
+{
+ struct bpf_insn_array *insn_array = cast_insn_array(map);
+ u32 index = *(u32 *)key;
+
+ if (unlikely(index >= insn_array->map.max_entries))
+ return NULL;
+
+ return &insn_array->values[index];
+}
+
+static long insn_array_update_elem(struct bpf_map *map, void *key, void *value, u64 map_flags)
+{
+ struct bpf_insn_array *insn_array = cast_insn_array(map);
+ u32 index = *(u32 *)key;
+ struct bpf_insn_array_value val = {};
+
+ if (unlikely(index >= insn_array->map.max_entries))
+ return -E2BIG;
+
+ if (unlikely(map_flags & BPF_NOEXIST))
+ return -EEXIST;
+
+ copy_map_value(map, &val, value);
+ if (val.jitted_off || val.xlated_off)
+ return -EINVAL;
+
+ insn_array->values[index].orig_off = val.orig_off;
+
+ return 0;
+}
+
+static long insn_array_delete_elem(struct bpf_map *map, void *key)
+{
+ return -EINVAL;
+}
+
+static int insn_array_check_btf(const struct bpf_map *map,
+ const struct btf *btf,
+ const struct btf_type *key_type,
+ const struct btf_type *value_type)
+{
+ if (!btf_type_is_i32(key_type))
+ return -EINVAL;
+
+ if (!btf_type_is_i64(value_type))
+ return -EINVAL;
+
+ return 0;
+}
+
+static u64 insn_array_mem_usage(const struct bpf_map *map)
+{
+ return insn_array_alloc_size(map->max_entries);
+}
+
+BTF_ID_LIST_SINGLE(insn_array_btf_ids, struct, bpf_insn_array)
+
+const struct bpf_map_ops insn_array_map_ops = {
+ .map_alloc_check = insn_array_alloc_check,
+ .map_alloc = insn_array_alloc,
+ .map_free = insn_array_free,
+ .map_get_next_key = bpf_array_get_next_key,
+ .map_lookup_elem = insn_array_lookup_elem,
+ .map_update_elem = insn_array_update_elem,
+ .map_delete_elem = insn_array_delete_elem,
+ .map_check_btf = insn_array_check_btf,
+ .map_mem_usage = insn_array_mem_usage,
+ .map_btf_id = &insn_array_btf_ids[0],
+};
+
+static inline bool is_frozen(struct bpf_map *map)
+{
+ guard(mutex)(&map->freeze_mutex);
+
+ return map->frozen;
+}
+
+static bool is_insn_array(const struct bpf_map *map)
+{
+ return map->map_type == BPF_MAP_TYPE_INSN_ARRAY;
+}
+
+static inline bool valid_offsets(const struct bpf_insn_array *insn_array,
+ const struct bpf_prog *prog)
+{
+ u32 off;
+ int i;
+
+ for (i = 0; i < insn_array->map.max_entries; i++) {
+ off = insn_array->values[i].orig_off;
+
+ if (off >= prog->len)
+ return false;
+
+ if (off > 0) {
+ if (prog->insnsi[off-1].code == (BPF_LD | BPF_DW | BPF_IMM))
+ return false;
+ }
+ }
+
+ return true;
+}
+
+int bpf_insn_array_init(struct bpf_map *map, const struct bpf_prog *prog)
+{
+ struct bpf_insn_array *insn_array = cast_insn_array(map);
+ struct bpf_insn_array_value *values = insn_array->values;
+ int i;
+
+ if (!is_frozen(map))
+ return -EINVAL;
+
+ if (!valid_offsets(insn_array, prog))
+ return -EINVAL;
+
+ /*
+ * There can be only one program using the map
+ */
+ if (atomic_xchg(&insn_array->used, 1))
+ return -EBUSY;
+
+ /*
+ * Reset all the map indexes to the original values. This is needed,
+ * e.g., when a replay of verification with different log level should
+ * be performed.
+ */
+ for (i = 0; i < map->max_entries; i++)
+ values[i].xlated_off = values[i].orig_off;
+
+ return 0;
+}
+
+int bpf_insn_array_ready(struct bpf_map *map)
+{
+ struct bpf_insn_array *insn_array = cast_insn_array(map);
+ int i;
+
+ for (i = 0; i < map->max_entries; i++) {
+ if (insn_array->values[i].xlated_off == INSN_DELETED)
+ continue;
+ if (!insn_array->ips[i])
+ return -EFAULT;
+ }
+
+ return 0;
+}
+
+void bpf_insn_array_release(struct bpf_map *map)
+{
+ struct bpf_insn_array *insn_array = cast_insn_array(map);
+
+ atomic_set(&insn_array->used, 0);
+}
+
+void bpf_insn_array_adjust(struct bpf_map *map, u32 off, u32 len)
+{
+ struct bpf_insn_array *insn_array = cast_insn_array(map);
+ int i;
+
+ if (len <= 1)
+ return;
+
+ for (i = 0; i < map->max_entries; i++) {
+ if (insn_array->values[i].xlated_off <= off)
+ continue;
+ if (insn_array->values[i].xlated_off == INSN_DELETED)
+ continue;
+ insn_array->values[i].xlated_off += len - 1;
+ }
+}
+
+void bpf_insn_array_adjust_after_remove(struct bpf_map *map, u32 off, u32 len)
+{
+ struct bpf_insn_array *insn_array = cast_insn_array(map);
+ int i;
+
+ for (i = 0; i < map->max_entries; i++) {
+ if (insn_array->values[i].xlated_off < off)
+ continue;
+ if (insn_array->values[i].xlated_off == INSN_DELETED)
+ continue;
+ if (insn_array->values[i].xlated_off < off + len)
+ insn_array->values[i].xlated_off = INSN_DELETED;
+ else
+ insn_array->values[i].xlated_off -= len;
+ }
+}
+
+/*
+ * This function is called by JITs. The image is the real program
+ * image, the offsets array set up the xlated -> jitted mapping.
+ * The offsets[xlated] offset should point to the beginning of
+ * the jitted instruction.
+ */
+void bpf_prog_update_insn_ptrs(struct bpf_prog *prog, u32 *offsets, void *image)
+{
+ struct bpf_insn_array *insn_array;
+ struct bpf_map *map;
+ u32 xlated_off;
+ int i, j;
+
+ if (!offsets || !image)
+ return;
+
+ for (i = 0; i < prog->aux->used_map_cnt; i++) {
+ map = prog->aux->used_maps[i];
+ if (!is_insn_array(map))
+ continue;
+
+ insn_array = cast_insn_array(map);
+ for (j = 0; j < map->max_entries; j++) {
+ xlated_off = insn_array->values[j].xlated_off;
+ if (xlated_off == INSN_DELETED)
+ continue;
+ if (xlated_off < prog->aux->subprog_start)
+ continue;
+ xlated_off -= prog->aux->subprog_start;
+ if (xlated_off >= prog->len)
+ continue;
+
+ insn_array->values[j].jitted_off = offsets[xlated_off];
+ insn_array->ips[j] = (long)(image + offsets[xlated_off]);
+ }
+ }
+}
diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c
index 8a129746bd6c..f62d61b6730a 100644
--- a/kernel/bpf/syscall.c
+++ b/kernel/bpf/syscall.c
@@ -1493,6 +1493,7 @@ static int map_create(union bpf_attr *attr, bpfptr_t uattr)
case BPF_MAP_TYPE_STRUCT_OPS:
case BPF_MAP_TYPE_CPUMAP:
case BPF_MAP_TYPE_ARENA:
+ case BPF_MAP_TYPE_INSN_ARRAY:
if (!bpf_token_capable(token, CAP_BPF))
goto put_token;
break;
@@ -2853,6 +2854,23 @@ static int bpf_prog_verify_signature(struct bpf_prog *prog, union bpf_attr *attr
return err;
}
+static int bpf_prog_mark_insn_arrays_ready(struct bpf_prog *prog)
+{
+ int err;
+ int i;
+
+ for (i = 0; i < prog->aux->used_map_cnt; i++) {
+ if (prog->aux->used_maps[i]->map_type != BPF_MAP_TYPE_INSN_ARRAY)
+ continue;
+
+ err = bpf_insn_array_ready(prog->aux->used_maps[i]);
+ if (err)
+ return err;
+ }
+
+ return 0;
+}
+
/* last field in 'union bpf_attr' used by this command */
#define BPF_PROG_LOAD_LAST_FIELD keyring_id
@@ -3082,6 +3100,10 @@ static int bpf_prog_load(union bpf_attr *attr, bpfptr_t uattr, u32 uattr_size)
if (err < 0)
goto free_used_maps;
+ err = bpf_prog_mark_insn_arrays_ready(prog);
+ if (err < 0)
+ goto free_used_maps;
+
err = bpf_prog_alloc_id(prog);
if (err)
goto free_used_maps;
diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c
index e4928846e763..dfe5741812b9 100644
--- a/kernel/bpf/verifier.c
+++ b/kernel/bpf/verifier.c
@@ -10086,6 +10086,8 @@ static int check_map_func_compatibility(struct bpf_verifier_env *env,
func_id != BPF_FUNC_map_push_elem)
goto error;
break;
+ case BPF_MAP_TYPE_INSN_ARRAY:
+ goto error;
default:
break;
}
@@ -20582,6 +20584,15 @@ static int __add_used_map(struct bpf_verifier_env *env, struct bpf_map *map)
env->used_maps[env->used_map_cnt++] = map;
+ if (map->map_type == BPF_MAP_TYPE_INSN_ARRAY) {
+ err = bpf_insn_array_init(map, env->prog);
+ if (err) {
+ verbose(env, "Failed to properly initialize insn array\n");
+ return err;
+ }
+ env->insn_array_maps[env->insn_array_map_cnt++] = map;
+ }
+
return env->used_map_cnt - 1;
}
@@ -20828,6 +20839,33 @@ static void adjust_subprog_starts(struct bpf_verifier_env *env, u32 off, u32 len
}
}
+static void release_insn_arrays(struct bpf_verifier_env *env)
+{
+ int i;
+
+ for (i = 0; i < env->insn_array_map_cnt; i++)
+ bpf_insn_array_release(env->insn_array_maps[i]);
+}
+
+static void adjust_insn_arrays(struct bpf_verifier_env *env, u32 off, u32 len)
+{
+ int i;
+
+ if (len == 1)
+ return;
+
+ for (i = 0; i < env->insn_array_map_cnt; i++)
+ bpf_insn_array_adjust(env->insn_array_maps[i], off, len);
+}
+
+static void adjust_insn_arrays_after_remove(struct bpf_verifier_env *env, u32 off, u32 len)
+{
+ int i;
+
+ for (i = 0; i < env->insn_array_map_cnt; i++)
+ bpf_insn_array_adjust_after_remove(env->insn_array_maps[i], off, len);
+}
+
static void adjust_poke_descs(struct bpf_prog *prog, u32 off, u32 len)
{
struct bpf_jit_poke_descriptor *tab = prog->aux->poke_tab;
@@ -20869,6 +20907,7 @@ static struct bpf_prog *bpf_patch_insn_data(struct bpf_verifier_env *env, u32 of
}
adjust_insn_aux_data(env, new_prog, off, len);
adjust_subprog_starts(env, off, len);
+ adjust_insn_arrays(env, off, len);
adjust_poke_descs(new_prog, off, len);
return new_prog;
}
@@ -21052,6 +21091,8 @@ static int verifier_remove_insns(struct bpf_verifier_env *env, u32 off, u32 cnt)
if (err)
return err;
+ adjust_insn_arrays_after_remove(env, off, cnt);
+
memmove(aux_data + off, aux_data + off + cnt,
sizeof(*aux_data) * (orig_prog_len - off - cnt));
@@ -21695,6 +21736,8 @@ static int jit_subprogs(struct bpf_verifier_env *env)
func[i]->aux->jited_linfo = prog->aux->jited_linfo;
func[i]->aux->linfo_idx = env->subprog_info[i].linfo_idx;
func[i]->aux->arena = prog->aux->arena;
+ func[i]->aux->used_maps = env->used_maps;
+ func[i]->aux->used_map_cnt = env->used_map_cnt;
num_exentries = 0;
insn = func[i]->insnsi;
for (j = 0; j < func[i]->len; j++, insn++) {
@@ -24871,6 +24914,8 @@ skip_full_check:
adjust_btf_func(env);
err_release_maps:
+ if (ret)
+ release_insn_arrays(env);
if (!env->prog->aux->used_maps)
/* if we didn't copy map pointers into bpf_prog_info, release
* them now. Otherwise free_used_maps() will release them.
diff --git a/tools/include/uapi/linux/bpf.h b/tools/include/uapi/linux/bpf.h
index 1d73f165394d..f5713f59ac10 100644
--- a/tools/include/uapi/linux/bpf.h
+++ b/tools/include/uapi/linux/bpf.h
@@ -1026,6 +1026,7 @@ enum bpf_map_type {
BPF_MAP_TYPE_USER_RINGBUF,
BPF_MAP_TYPE_CGRP_STORAGE,
BPF_MAP_TYPE_ARENA,
+ BPF_MAP_TYPE_INSN_ARRAY,
__MAX_BPF_MAP_TYPE
};
@@ -7649,4 +7650,24 @@ enum bpf_kfunc_flags {
BPF_F_PAD_ZEROS = (1ULL << 0),
};
+/*
+ * Values of a BPF_MAP_TYPE_INSN_ARRAY entry must be of this type.
+ *
+ * Before the map is used the orig_off field should point to an
+ * instruction inside the program being loaded. The other fields
+ * must be set to 0.
+ *
+ * After the program is loaded, the xlated_off will be adjusted
+ * by the verifier to point to the index of the original instruction
+ * in the xlated program. If the instruction is deleted, it will
+ * be set to (u32)-1. The jitted_off will be set to the corresponding
+ * offset in the jitted image of the program.
+ */
+struct bpf_insn_array_value {
+ __u32 orig_off;
+ __u32 xlated_off;
+ __u32 jitted_off;
+ __u32 :32;
+};
+
#endif /* _UAPI__LINUX_BPF_H__ */