diff options
-rw-r--r-- | include/linux/bpf.h | 9 | ||||
-rw-r--r-- | include/linux/bpf_verifier.h | 16 | ||||
-rw-r--r-- | kernel/bpf/btf.c | 26 | ||||
-rw-r--r-- | kernel/bpf/syscall.c | 6 | ||||
-rw-r--r-- | kernel/bpf/verifier.c | 219 |
5 files changed, 231 insertions, 45 deletions
diff --git a/include/linux/bpf.h b/include/linux/bpf.h index e3928fb19c2c..7a87ecfa2c3f 100644 --- a/include/linux/bpf.h +++ b/include/linux/bpf.h @@ -205,6 +205,7 @@ enum btf_field_type { BPF_REFCOUNT = (1 << 9), BPF_WORKQUEUE = (1 << 10), BPF_UPTR = (1 << 11), + BPF_RES_SPIN_LOCK = (1 << 12), }; typedef void (*btf_dtor_kfunc_t)(void *); @@ -240,6 +241,7 @@ struct btf_record { u32 cnt; u32 field_mask; int spin_lock_off; + int res_spin_lock_off; int timer_off; int wq_off; int refcount_off; @@ -315,6 +317,8 @@ static inline const char *btf_field_type_name(enum btf_field_type type) switch (type) { case BPF_SPIN_LOCK: return "bpf_spin_lock"; + case BPF_RES_SPIN_LOCK: + return "bpf_res_spin_lock"; case BPF_TIMER: return "bpf_timer"; case BPF_WORKQUEUE: @@ -347,6 +351,8 @@ static inline u32 btf_field_type_size(enum btf_field_type type) switch (type) { case BPF_SPIN_LOCK: return sizeof(struct bpf_spin_lock); + case BPF_RES_SPIN_LOCK: + return sizeof(struct bpf_res_spin_lock); case BPF_TIMER: return sizeof(struct bpf_timer); case BPF_WORKQUEUE: @@ -377,6 +383,8 @@ static inline u32 btf_field_type_align(enum btf_field_type type) switch (type) { case BPF_SPIN_LOCK: return __alignof__(struct bpf_spin_lock); + case BPF_RES_SPIN_LOCK: + return __alignof__(struct bpf_res_spin_lock); case BPF_TIMER: return __alignof__(struct bpf_timer); case BPF_WORKQUEUE: @@ -420,6 +428,7 @@ static inline void bpf_obj_init_field(const struct btf_field *field, void *addr) case BPF_RB_ROOT: /* RB_ROOT_CACHED 0-inits, no need to do anything after memset */ case BPF_SPIN_LOCK: + case BPF_RES_SPIN_LOCK: case BPF_TIMER: case BPF_WORKQUEUE: case BPF_KPTR_UNREF: diff --git a/include/linux/bpf_verifier.h b/include/linux/bpf_verifier.h index d6cfc4ee6820..bc073a48aed9 100644 --- a/include/linux/bpf_verifier.h +++ b/include/linux/bpf_verifier.h @@ -115,6 +115,14 @@ struct bpf_reg_state { int depth:30; } iter; + /* For irq stack slots */ + struct { + enum { + IRQ_NATIVE_KFUNC, + IRQ_LOCK_KFUNC, + } kfunc_class; + } irq; + /* Max size from any of the above. */ struct { unsigned long raw1; @@ -255,9 +263,11 @@ struct bpf_reference_state { * default to pointer reference on zero initialization of a state. */ enum ref_state_type { - REF_TYPE_PTR = 1, - REF_TYPE_IRQ = 2, - REF_TYPE_LOCK = 3, + REF_TYPE_PTR = (1 << 1), + REF_TYPE_IRQ = (1 << 2), + REF_TYPE_LOCK = (1 << 3), + REF_TYPE_RES_LOCK = (1 << 4), + REF_TYPE_RES_LOCK_IRQ = (1 << 5), } type; /* Track each reference created with a unique id, even if the same * instruction creates the reference multiple times (eg, via CALL). diff --git a/kernel/bpf/btf.c b/kernel/bpf/btf.c index 519e3f5e9c10..f7a2bfb0c11a 100644 --- a/kernel/bpf/btf.c +++ b/kernel/bpf/btf.c @@ -3481,6 +3481,15 @@ static int btf_get_field_type(const struct btf *btf, const struct btf_type *var_ goto end; } } + if (field_mask & BPF_RES_SPIN_LOCK) { + if (!strcmp(name, "bpf_res_spin_lock")) { + if (*seen_mask & BPF_RES_SPIN_LOCK) + return -E2BIG; + *seen_mask |= BPF_RES_SPIN_LOCK; + type = BPF_RES_SPIN_LOCK; + goto end; + } + } if (field_mask & BPF_TIMER) { if (!strcmp(name, "bpf_timer")) { if (*seen_mask & BPF_TIMER) @@ -3659,6 +3668,7 @@ static int btf_find_field_one(const struct btf *btf, switch (field_type) { case BPF_SPIN_LOCK: + case BPF_RES_SPIN_LOCK: case BPF_TIMER: case BPF_WORKQUEUE: case BPF_LIST_NODE: @@ -3952,6 +3962,7 @@ struct btf_record *btf_parse_fields(const struct btf *btf, const struct btf_type return ERR_PTR(-ENOMEM); rec->spin_lock_off = -EINVAL; + rec->res_spin_lock_off = -EINVAL; rec->timer_off = -EINVAL; rec->wq_off = -EINVAL; rec->refcount_off = -EINVAL; @@ -3979,6 +3990,11 @@ struct btf_record *btf_parse_fields(const struct btf *btf, const struct btf_type /* Cache offset for faster lookup at runtime */ rec->spin_lock_off = rec->fields[i].offset; break; + case BPF_RES_SPIN_LOCK: + WARN_ON_ONCE(rec->spin_lock_off >= 0); + /* Cache offset for faster lookup at runtime */ + rec->res_spin_lock_off = rec->fields[i].offset; + break; case BPF_TIMER: WARN_ON_ONCE(rec->timer_off >= 0); /* Cache offset for faster lookup at runtime */ @@ -4022,9 +4038,15 @@ struct btf_record *btf_parse_fields(const struct btf *btf, const struct btf_type rec->cnt++; } + if (rec->spin_lock_off >= 0 && rec->res_spin_lock_off >= 0) { + ret = -EINVAL; + goto end; + } + /* bpf_{list_head, rb_node} require bpf_spin_lock */ if ((btf_record_has_field(rec, BPF_LIST_HEAD) || - btf_record_has_field(rec, BPF_RB_ROOT)) && rec->spin_lock_off < 0) { + btf_record_has_field(rec, BPF_RB_ROOT)) && + (rec->spin_lock_off < 0 && rec->res_spin_lock_off < 0)) { ret = -EINVAL; goto end; } @@ -5637,7 +5659,7 @@ btf_parse_struct_metas(struct bpf_verifier_log *log, struct btf *btf) type = &tab->types[tab->cnt]; type->btf_id = i; - record = btf_parse_fields(btf, t, BPF_SPIN_LOCK | BPF_LIST_HEAD | BPF_LIST_NODE | + record = btf_parse_fields(btf, t, BPF_SPIN_LOCK | BPF_RES_SPIN_LOCK | BPF_LIST_HEAD | BPF_LIST_NODE | BPF_RB_ROOT | BPF_RB_NODE | BPF_REFCOUNT | BPF_KPTR, t->size); /* The record cannot be unset, treat it as an error if so */ diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c index 380b445a304c..77062799143e 100644 --- a/kernel/bpf/syscall.c +++ b/kernel/bpf/syscall.c @@ -648,6 +648,7 @@ void btf_record_free(struct btf_record *rec) case BPF_RB_ROOT: case BPF_RB_NODE: case BPF_SPIN_LOCK: + case BPF_RES_SPIN_LOCK: case BPF_TIMER: case BPF_REFCOUNT: case BPF_WORKQUEUE: @@ -700,6 +701,7 @@ struct btf_record *btf_record_dup(const struct btf_record *rec) case BPF_RB_ROOT: case BPF_RB_NODE: case BPF_SPIN_LOCK: + case BPF_RES_SPIN_LOCK: case BPF_TIMER: case BPF_REFCOUNT: case BPF_WORKQUEUE: @@ -777,6 +779,7 @@ void bpf_obj_free_fields(const struct btf_record *rec, void *obj) switch (fields[i].type) { case BPF_SPIN_LOCK: + case BPF_RES_SPIN_LOCK: break; case BPF_TIMER: bpf_timer_cancel_and_free(field_ptr); @@ -1212,7 +1215,7 @@ static int map_check_btf(struct bpf_map *map, struct bpf_token *token, return -EINVAL; map->record = btf_parse_fields(btf, value_type, - BPF_SPIN_LOCK | BPF_TIMER | BPF_KPTR | BPF_LIST_HEAD | + BPF_SPIN_LOCK | BPF_RES_SPIN_LOCK | BPF_TIMER | BPF_KPTR | BPF_LIST_HEAD | BPF_RB_ROOT | BPF_REFCOUNT | BPF_WORKQUEUE | BPF_UPTR, map->value_size); if (!IS_ERR_OR_NULL(map->record)) { @@ -1231,6 +1234,7 @@ static int map_check_btf(struct bpf_map *map, struct bpf_token *token, case 0: continue; case BPF_SPIN_LOCK: + case BPF_RES_SPIN_LOCK: if (map->map_type != BPF_MAP_TYPE_HASH && map->map_type != BPF_MAP_TYPE_ARRAY && map->map_type != BPF_MAP_TYPE_CGROUP_STORAGE && diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c index 3303a3605ee8..29121ad32a89 100644 --- a/kernel/bpf/verifier.c +++ b/kernel/bpf/verifier.c @@ -456,7 +456,7 @@ static bool subprog_is_exc_cb(struct bpf_verifier_env *env, int subprog) static bool reg_may_point_to_spin_lock(const struct bpf_reg_state *reg) { - return btf_record_has_field(reg_btf_record(reg), BPF_SPIN_LOCK); + return btf_record_has_field(reg_btf_record(reg), BPF_SPIN_LOCK | BPF_RES_SPIN_LOCK); } static bool type_is_rdonly_mem(u32 type) @@ -1155,7 +1155,8 @@ static int release_irq_state(struct bpf_verifier_state *state, int id); static int mark_stack_slot_irq_flag(struct bpf_verifier_env *env, struct bpf_kfunc_call_arg_meta *meta, - struct bpf_reg_state *reg, int insn_idx) + struct bpf_reg_state *reg, int insn_idx, + int kfunc_class) { struct bpf_func_state *state = func(env, reg); struct bpf_stack_state *slot; @@ -1177,6 +1178,7 @@ static int mark_stack_slot_irq_flag(struct bpf_verifier_env *env, st->type = PTR_TO_STACK; /* we don't have dedicated reg type */ st->live |= REG_LIVE_WRITTEN; st->ref_obj_id = id; + st->irq.kfunc_class = kfunc_class; for (i = 0; i < BPF_REG_SIZE; i++) slot->slot_type[i] = STACK_IRQ_FLAG; @@ -1185,7 +1187,8 @@ static int mark_stack_slot_irq_flag(struct bpf_verifier_env *env, return 0; } -static int unmark_stack_slot_irq_flag(struct bpf_verifier_env *env, struct bpf_reg_state *reg) +static int unmark_stack_slot_irq_flag(struct bpf_verifier_env *env, struct bpf_reg_state *reg, + int kfunc_class) { struct bpf_func_state *state = func(env, reg); struct bpf_stack_state *slot; @@ -1199,6 +1202,15 @@ static int unmark_stack_slot_irq_flag(struct bpf_verifier_env *env, struct bpf_r slot = &state->stack[spi]; st = &slot->spilled_ptr; + if (st->irq.kfunc_class != kfunc_class) { + const char *flag_kfunc = st->irq.kfunc_class == IRQ_NATIVE_KFUNC ? "native" : "lock"; + const char *used_kfunc = kfunc_class == IRQ_NATIVE_KFUNC ? "native" : "lock"; + + verbose(env, "irq flag acquired by %s kfuncs cannot be restored with %s kfuncs\n", + flag_kfunc, used_kfunc); + return -EINVAL; + } + err = release_irq_state(env->cur_state, st->ref_obj_id); WARN_ON_ONCE(err && err != -EACCES); if (err) { @@ -1609,7 +1621,7 @@ static struct bpf_reference_state *find_lock_state(struct bpf_verifier_state *st for (i = 0; i < state->acquired_refs; i++) { struct bpf_reference_state *s = &state->refs[i]; - if (s->type != type) + if (!(s->type & type)) continue; if (s->id == id && s->ptr == ptr) @@ -8204,6 +8216,12 @@ static int check_kfunc_mem_size_reg(struct bpf_verifier_env *env, struct bpf_reg return err; } +enum { + PROCESS_SPIN_LOCK = (1 << 0), + PROCESS_RES_LOCK = (1 << 1), + PROCESS_LOCK_IRQ = (1 << 2), +}; + /* Implementation details: * bpf_map_lookup returns PTR_TO_MAP_VALUE_OR_NULL. * bpf_obj_new returns PTR_TO_BTF_ID | MEM_ALLOC | PTR_MAYBE_NULL. @@ -8226,30 +8244,33 @@ static int check_kfunc_mem_size_reg(struct bpf_verifier_env *env, struct bpf_reg * env->cur_state->active_locks remembers which map value element or allocated * object got locked and clears it after bpf_spin_unlock. */ -static int process_spin_lock(struct bpf_verifier_env *env, int regno, - bool is_lock) +static int process_spin_lock(struct bpf_verifier_env *env, int regno, int flags) { + bool is_lock = flags & PROCESS_SPIN_LOCK, is_res_lock = flags & PROCESS_RES_LOCK; + const char *lock_str = is_res_lock ? "bpf_res_spin" : "bpf_spin"; struct bpf_reg_state *regs = cur_regs(env), *reg = ®s[regno]; struct bpf_verifier_state *cur = env->cur_state; bool is_const = tnum_is_const(reg->var_off); + bool is_irq = flags & PROCESS_LOCK_IRQ; u64 val = reg->var_off.value; struct bpf_map *map = NULL; struct btf *btf = NULL; struct btf_record *rec; + u32 spin_lock_off; int err; if (!is_const) { verbose(env, - "R%d doesn't have constant offset. bpf_spin_lock has to be at the constant offset\n", - regno); + "R%d doesn't have constant offset. %s_lock has to be at the constant offset\n", + regno, lock_str); return -EINVAL; } if (reg->type == PTR_TO_MAP_VALUE) { map = reg->map_ptr; if (!map->btf) { verbose(env, - "map '%s' has to have BTF in order to use bpf_spin_lock\n", - map->name); + "map '%s' has to have BTF in order to use %s_lock\n", + map->name, lock_str); return -EINVAL; } } else { @@ -8257,36 +8278,53 @@ static int process_spin_lock(struct bpf_verifier_env *env, int regno, } rec = reg_btf_record(reg); - if (!btf_record_has_field(rec, BPF_SPIN_LOCK)) { - verbose(env, "%s '%s' has no valid bpf_spin_lock\n", map ? "map" : "local", - map ? map->name : "kptr"); + if (!btf_record_has_field(rec, is_res_lock ? BPF_RES_SPIN_LOCK : BPF_SPIN_LOCK)) { + verbose(env, "%s '%s' has no valid %s_lock\n", map ? "map" : "local", + map ? map->name : "kptr", lock_str); return -EINVAL; } - if (rec->spin_lock_off != val + reg->off) { - verbose(env, "off %lld doesn't point to 'struct bpf_spin_lock' that is at %d\n", - val + reg->off, rec->spin_lock_off); + spin_lock_off = is_res_lock ? rec->res_spin_lock_off : rec->spin_lock_off; + if (spin_lock_off != val + reg->off) { + verbose(env, "off %lld doesn't point to 'struct %s_lock' that is at %d\n", + val + reg->off, lock_str, spin_lock_off); return -EINVAL; } if (is_lock) { void *ptr; + int type; if (map) ptr = map; else ptr = btf; - if (cur->active_locks) { - verbose(env, - "Locking two bpf_spin_locks are not allowed\n"); - return -EINVAL; + if (!is_res_lock && cur->active_locks) { + if (find_lock_state(env->cur_state, REF_TYPE_LOCK, 0, NULL)) { + verbose(env, + "Locking two bpf_spin_locks are not allowed\n"); + return -EINVAL; + } + } else if (is_res_lock && cur->active_locks) { + if (find_lock_state(env->cur_state, REF_TYPE_RES_LOCK | REF_TYPE_RES_LOCK_IRQ, reg->id, ptr)) { + verbose(env, "Acquiring the same lock again, AA deadlock detected\n"); + return -EINVAL; + } } - err = acquire_lock_state(env, env->insn_idx, REF_TYPE_LOCK, reg->id, ptr); + + if (is_res_lock && is_irq) + type = REF_TYPE_RES_LOCK_IRQ; + else if (is_res_lock) + type = REF_TYPE_RES_LOCK; + else + type = REF_TYPE_LOCK; + err = acquire_lock_state(env, env->insn_idx, type, reg->id, ptr); if (err < 0) { verbose(env, "Failed to acquire lock state\n"); return err; } } else { void *ptr; + int type; if (map) ptr = map; @@ -8294,12 +8332,18 @@ static int process_spin_lock(struct bpf_verifier_env *env, int regno, ptr = btf; if (!cur->active_locks) { - verbose(env, "bpf_spin_unlock without taking a lock\n"); + verbose(env, "%s_unlock without taking a lock\n", lock_str); return -EINVAL; } - if (release_lock_state(env->cur_state, REF_TYPE_LOCK, reg->id, ptr)) { - verbose(env, "bpf_spin_unlock of different lock\n"); + if (is_res_lock && is_irq) + type = REF_TYPE_RES_LOCK_IRQ; + else if (is_res_lock) + type = REF_TYPE_RES_LOCK; + else + type = REF_TYPE_LOCK; + if (release_lock_state(cur, type, reg->id, ptr)) { + verbose(env, "%s_unlock of different lock\n", lock_str); return -EINVAL; } @@ -9625,11 +9669,11 @@ skip_type_check: return -EACCES; } if (meta->func_id == BPF_FUNC_spin_lock) { - err = process_spin_lock(env, regno, true); + err = process_spin_lock(env, regno, PROCESS_SPIN_LOCK); if (err) return err; } else if (meta->func_id == BPF_FUNC_spin_unlock) { - err = process_spin_lock(env, regno, false); + err = process_spin_lock(env, regno, 0); if (err) return err; } else { @@ -11511,7 +11555,7 @@ static int check_helper_call(struct bpf_verifier_env *env, struct bpf_insn *insn regs[BPF_REG_0].map_uid = meta.map_uid; regs[BPF_REG_0].type = PTR_TO_MAP_VALUE | ret_flag; if (!type_may_be_null(ret_flag) && - btf_record_has_field(meta.map_ptr->record, BPF_SPIN_LOCK)) { + btf_record_has_field(meta.map_ptr->record, BPF_SPIN_LOCK | BPF_RES_SPIN_LOCK)) { regs[BPF_REG_0].id = ++env->id_gen; } break; @@ -11683,10 +11727,10 @@ static int check_helper_call(struct bpf_verifier_env *env, struct bpf_insn *insn /* mark_btf_func_reg_size() is used when the reg size is determined by * the BTF func_proto's return value size and argument. */ -static void mark_btf_func_reg_size(struct bpf_verifier_env *env, u32 regno, - size_t reg_size) +static void __mark_btf_func_reg_size(struct bpf_verifier_env *env, struct bpf_reg_state *regs, + u32 regno, size_t reg_size) { - struct bpf_reg_state *reg = &cur_regs(env)[regno]; + struct bpf_reg_state *reg = ®s[regno]; if (regno == BPF_REG_0) { /* Function return value */ @@ -11704,6 +11748,12 @@ static void mark_btf_func_reg_size(struct bpf_verifier_env *env, u32 regno, } } +static void mark_btf_func_reg_size(struct bpf_verifier_env *env, u32 regno, + size_t reg_size) +{ + return __mark_btf_func_reg_size(env, cur_regs(env), regno, reg_size); +} + static bool is_kfunc_acquire(struct bpf_kfunc_call_arg_meta *meta) { return meta->kfunc_flags & KF_ACQUIRE; @@ -11841,6 +11891,7 @@ enum { KF_ARG_RB_ROOT_ID, KF_ARG_RB_NODE_ID, KF_ARG_WORKQUEUE_ID, + KF_ARG_RES_SPIN_LOCK_ID, }; BTF_ID_LIST(kf_arg_btf_ids) @@ -11850,6 +11901,7 @@ BTF_ID(struct, bpf_list_node) BTF_ID(struct, bpf_rb_root) BTF_ID(struct, bpf_rb_node) BTF_ID(struct, bpf_wq) +BTF_ID(struct, bpf_res_spin_lock) static bool __is_kfunc_ptr_arg_type(const struct btf *btf, const struct btf_param *arg, int type) @@ -11898,6 +11950,11 @@ static bool is_kfunc_arg_wq(const struct btf *btf, const struct btf_param *arg) return __is_kfunc_ptr_arg_type(btf, arg, KF_ARG_WORKQUEUE_ID); } +static bool is_kfunc_arg_res_spin_lock(const struct btf *btf, const struct btf_param *arg) +{ + return __is_kfunc_ptr_arg_type(btf, arg, KF_ARG_RES_SPIN_LOCK_ID); +} + static bool is_kfunc_arg_callback(struct bpf_verifier_env *env, const struct btf *btf, const struct btf_param *arg) { @@ -11969,6 +12026,7 @@ enum kfunc_ptr_arg_type { KF_ARG_PTR_TO_MAP, KF_ARG_PTR_TO_WORKQUEUE, KF_ARG_PTR_TO_IRQ_FLAG, + KF_ARG_PTR_TO_RES_SPIN_LOCK, }; enum special_kfunc_type { @@ -12007,6 +12065,10 @@ enum special_kfunc_type { KF_bpf_iter_num_destroy, KF_bpf_set_dentry_xattr, KF_bpf_remove_dentry_xattr, + KF_bpf_res_spin_lock, + KF_bpf_res_spin_unlock, + KF_bpf_res_spin_lock_irqsave, + KF_bpf_res_spin_unlock_irqrestore, }; BTF_SET_START(special_kfunc_set) @@ -12096,6 +12158,10 @@ BTF_ID(func, bpf_remove_dentry_xattr) BTF_ID_UNUSED BTF_ID_UNUSED #endif +BTF_ID(func, bpf_res_spin_lock) +BTF_ID(func, bpf_res_spin_unlock) +BTF_ID(func, bpf_res_spin_lock_irqsave) +BTF_ID(func, bpf_res_spin_unlock_irqrestore) static bool is_kfunc_ret_null(struct bpf_kfunc_call_arg_meta *meta) { @@ -12189,6 +12255,9 @@ get_kfunc_ptr_arg_type(struct bpf_verifier_env *env, if (is_kfunc_arg_irq_flag(meta->btf, &args[argno])) return KF_ARG_PTR_TO_IRQ_FLAG; + if (is_kfunc_arg_res_spin_lock(meta->btf, &args[argno])) + return KF_ARG_PTR_TO_RES_SPIN_LOCK; + if ((base_type(reg->type) == PTR_TO_BTF_ID || reg2btf_ids[base_type(reg->type)])) { if (!btf_type_is_struct(ref_t)) { verbose(env, "kernel function %s args#%d pointer type %s %s is not supported\n", @@ -12296,13 +12365,19 @@ static int process_irq_flag(struct bpf_verifier_env *env, int regno, struct bpf_kfunc_call_arg_meta *meta) { struct bpf_reg_state *regs = cur_regs(env), *reg = ®s[regno]; + int err, kfunc_class = IRQ_NATIVE_KFUNC; bool irq_save; - int err; - if (meta->func_id == special_kfunc_list[KF_bpf_local_irq_save]) { + if (meta->func_id == special_kfunc_list[KF_bpf_local_irq_save] || + meta->func_id == special_kfunc_list[KF_bpf_res_spin_lock_irqsave]) { irq_save = true; - } else if (meta->func_id == special_kfunc_list[KF_bpf_local_irq_restore]) { + if (meta->func_id == special_kfunc_list[KF_bpf_res_spin_lock_irqsave]) + kfunc_class = IRQ_LOCK_KFUNC; + } else if (meta->func_id == special_kfunc_list[KF_bpf_local_irq_restore] || + meta->func_id == special_kfunc_list[KF_bpf_res_spin_unlock_irqrestore]) { irq_save = false; + if (meta->func_id == special_kfunc_list[KF_bpf_res_spin_unlock_irqrestore]) + kfunc_class = IRQ_LOCK_KFUNC; } else { verbose(env, "verifier internal error: unknown irq flags kfunc\n"); return -EFAULT; @@ -12318,7 +12393,7 @@ static int process_irq_flag(struct bpf_verifier_env *env, int regno, if (err) return err; - err = mark_stack_slot_irq_flag(env, meta, reg, env->insn_idx); + err = mark_stack_slot_irq_flag(env, meta, reg, env->insn_idx, kfunc_class); if (err) return err; } else { @@ -12332,7 +12407,7 @@ static int process_irq_flag(struct bpf_verifier_env *env, int regno, if (err) return err; - err = unmark_stack_slot_irq_flag(env, reg); + err = unmark_stack_slot_irq_flag(env, reg, kfunc_class); if (err) return err; } @@ -12459,7 +12534,8 @@ static int check_reg_allocation_locked(struct bpf_verifier_env *env, struct bpf_ if (!env->cur_state->active_locks) return -EINVAL; - s = find_lock_state(env->cur_state, REF_TYPE_LOCK, id, ptr); + s = find_lock_state(env->cur_state, REF_TYPE_LOCK | REF_TYPE_RES_LOCK | REF_TYPE_RES_LOCK_IRQ, + id, ptr); if (!s) { verbose(env, "held lock and object are not in the same allocation\n"); return -EINVAL; @@ -12495,9 +12571,18 @@ static bool is_bpf_graph_api_kfunc(u32 btf_id) btf_id == special_kfunc_list[KF_bpf_refcount_acquire_impl]; } +static bool is_bpf_res_spin_lock_kfunc(u32 btf_id) +{ + return btf_id == special_kfunc_list[KF_bpf_res_spin_lock] || + btf_id == special_kfunc_list[KF_bpf_res_spin_unlock] || + btf_id == special_kfunc_list[KF_bpf_res_spin_lock_irqsave] || + btf_id == special_kfunc_list[KF_bpf_res_spin_unlock_irqrestore]; +} + static bool kfunc_spin_allowed(u32 btf_id) { - return is_bpf_graph_api_kfunc(btf_id) || is_bpf_iter_num_api_kfunc(btf_id); + return is_bpf_graph_api_kfunc(btf_id) || is_bpf_iter_num_api_kfunc(btf_id) || + is_bpf_res_spin_lock_kfunc(btf_id); } static bool is_sync_callback_calling_kfunc(u32 btf_id) @@ -12929,6 +13014,7 @@ static int check_kfunc_args(struct bpf_verifier_env *env, struct bpf_kfunc_call_ case KF_ARG_PTR_TO_CONST_STR: case KF_ARG_PTR_TO_WORKQUEUE: case KF_ARG_PTR_TO_IRQ_FLAG: + case KF_ARG_PTR_TO_RES_SPIN_LOCK: break; default: WARN_ON_ONCE(1); @@ -13227,6 +13313,28 @@ static int check_kfunc_args(struct bpf_verifier_env *env, struct bpf_kfunc_call_ if (ret < 0) return ret; break; + case KF_ARG_PTR_TO_RES_SPIN_LOCK: + { + int flags = PROCESS_RES_LOCK; + + if (reg->type != PTR_TO_MAP_VALUE && reg->type != (PTR_TO_BTF_ID | MEM_ALLOC)) { + verbose(env, "arg#%d doesn't point to map value or allocated object\n", i); + return -EINVAL; + } + + if (!is_bpf_res_spin_lock_kfunc(meta->func_id)) + return -EFAULT; + if (meta->func_id == special_kfunc_list[KF_bpf_res_spin_lock] || + meta->func_id == special_kfunc_list[KF_bpf_res_spin_lock_irqsave]) + flags |= PROCESS_SPIN_LOCK; + if (meta->func_id == special_kfunc_list[KF_bpf_res_spin_lock_irqsave] || + meta->func_id == special_kfunc_list[KF_bpf_res_spin_unlock_irqrestore]) + flags |= PROCESS_LOCK_IRQ; + ret = process_spin_lock(env, regno, flags); + if (ret < 0) + return ret; + break; + } } } @@ -13312,6 +13420,33 @@ static int check_kfunc_call(struct bpf_verifier_env *env, struct bpf_insn *insn, insn_aux->is_iter_next = is_iter_next_kfunc(&meta); + if (!insn->off && + (insn->imm == special_kfunc_list[KF_bpf_res_spin_lock] || + insn->imm == special_kfunc_list[KF_bpf_res_spin_lock_irqsave])) { + struct bpf_verifier_state *branch; + struct bpf_reg_state *regs; + + branch = push_stack(env, env->insn_idx + 1, env->insn_idx, false); + if (!branch) { + verbose(env, "failed to push state for failed lock acquisition\n"); + return -ENOMEM; + } + + regs = branch->frame[branch->curframe]->regs; + + /* Clear r0-r5 registers in forked state */ + for (i = 0; i < CALLER_SAVED_REGS; i++) + mark_reg_not_init(env, regs, caller_saved[i]); + + mark_reg_unknown(env, regs, BPF_REG_0); + err = __mark_reg_s32_range(env, regs, BPF_REG_0, -MAX_ERRNO, -1); + if (err) { + verbose(env, "failed to mark s32 range for retval in forked state for lock\n"); + return err; + } + __mark_btf_func_reg_size(env, regs, BPF_REG_0, sizeof(u32)); + } + if (is_kfunc_destructive(&meta) && !capable(CAP_SYS_BOOT)) { verbose(env, "destructive kfunc calls require CAP_SYS_BOOT capability\n"); return -EACCES; @@ -13482,6 +13617,9 @@ static int check_kfunc_call(struct bpf_verifier_env *env, struct bpf_insn *insn, if (btf_type_is_scalar(t)) { mark_reg_unknown(env, regs, BPF_REG_0); + if (meta.btf == btf_vmlinux && (meta.func_id == special_kfunc_list[KF_bpf_res_spin_lock] || + meta.func_id == special_kfunc_list[KF_bpf_res_spin_lock_irqsave])) + __mark_reg_const_zero(env, ®s[BPF_REG_0]); mark_btf_func_reg_size(env, BPF_REG_0, t->size); } else if (btf_type_is_ptr(t)) { ptr_type = btf_type_skip_modifiers(desc_btf, t->type, &ptr_type_id); @@ -18417,7 +18555,8 @@ static bool stacksafe(struct bpf_verifier_env *env, struct bpf_func_state *old, case STACK_IRQ_FLAG: old_reg = &old->stack[spi].spilled_ptr; cur_reg = &cur->stack[spi].spilled_ptr; - if (!check_ids(old_reg->ref_obj_id, cur_reg->ref_obj_id, idmap)) + if (!check_ids(old_reg->ref_obj_id, cur_reg->ref_obj_id, idmap) || + old_reg->irq.kfunc_class != cur_reg->irq.kfunc_class) return false; break; case STACK_MISC: @@ -18461,6 +18600,8 @@ static bool refsafe(struct bpf_verifier_state *old, struct bpf_verifier_state *c case REF_TYPE_IRQ: break; case REF_TYPE_LOCK: + case REF_TYPE_RES_LOCK: + case REF_TYPE_RES_LOCK_IRQ: if (old->refs[i].ptr != cur->refs[i].ptr) return false; break; @@ -19746,7 +19887,7 @@ static int check_map_prog_compatibility(struct bpf_verifier_env *env, } } - if (btf_record_has_field(map->record, BPF_SPIN_LOCK)) { + if (btf_record_has_field(map->record, BPF_SPIN_LOCK | BPF_RES_SPIN_LOCK)) { if (prog_type == BPF_PROG_TYPE_SOCKET_FILTER) { verbose(env, "socket filter progs cannot use bpf_spin_lock yet\n"); return -EINVAL; |