diff options
Diffstat (limited to 'kernel')
33 files changed, 406 insertions, 143 deletions
diff --git a/kernel/bpf/btf.c b/kernel/bpf/btf.c index 715f9fcf4712..c57bd10340ed 100644 --- a/kernel/bpf/btf.c +++ b/kernel/bpf/btf.c @@ -467,7 +467,7 @@ static const struct btf_kind_operations *btf_type_ops(const struct btf_type *t) return kind_ops[BTF_INFO_KIND(t->info)]; } -bool btf_name_offset_valid(const struct btf *btf, u32 offset) +static bool btf_name_offset_valid(const struct btf *btf, u32 offset) { return BTF_STR_OFFSET_VALID(offset) && offset < btf->hdr.str_len; @@ -1219,8 +1219,6 @@ static void btf_bitfield_seq_show(void *data, u8 bits_offset, u8 nr_copy_bits; u64 print_num; - data += BITS_ROUNDDOWN_BYTES(bits_offset); - bits_offset = BITS_PER_BYTE_MASKED(bits_offset); nr_copy_bits = nr_bits + bits_offset; nr_copy_bytes = BITS_ROUNDUP_BYTES(nr_copy_bits); @@ -1255,7 +1253,9 @@ static void btf_int_bits_seq_show(const struct btf *btf, * BTF_INT_OFFSET() cannot exceed 64 bits. */ total_bits_offset = bits_offset + BTF_INT_OFFSET(int_data); - btf_bitfield_seq_show(data, total_bits_offset, nr_bits, m); + data += BITS_ROUNDDOWN_BYTES(total_bits_offset); + bits_offset = BITS_PER_BYTE_MASKED(total_bits_offset); + btf_bitfield_seq_show(data, bits_offset, nr_bits, m); } static void btf_int_seq_show(const struct btf *btf, const struct btf_type *t, @@ -1459,7 +1459,8 @@ static int btf_modifier_resolve(struct btf_verifier_env *env, /* "typedef void new_void", "const void"...etc */ if (!btf_type_is_void(next_type) && - !btf_type_is_fwd(next_type)) { + !btf_type_is_fwd(next_type) && + !btf_type_is_func_proto(next_type)) { btf_verifier_log_type(env, v->t, "Invalid type_id"); return -EINVAL; } @@ -2001,12 +2002,12 @@ static void btf_struct_seq_show(const struct btf *btf, const struct btf_type *t, member_offset = btf_member_bit_offset(t, member); bitfield_size = btf_member_bitfield_size(t, member); + bytes_offset = BITS_ROUNDDOWN_BYTES(member_offset); + bits8_offset = BITS_PER_BYTE_MASKED(member_offset); if (bitfield_size) { - btf_bitfield_seq_show(data, member_offset, + btf_bitfield_seq_show(data + bytes_offset, bits8_offset, bitfield_size, m); } else { - bytes_offset = BITS_ROUNDDOWN_BYTES(member_offset); - bits8_offset = BITS_PER_BYTE_MASKED(member_offset); ops = btf_type_ops(member_type); ops->seq_show(btf, member_type, member->type, data + bytes_offset, bits8_offset, m); diff --git a/kernel/bpf/cgroup.c b/kernel/bpf/cgroup.c index 9425c2fb872f..d17d05570a3f 100644 --- a/kernel/bpf/cgroup.c +++ b/kernel/bpf/cgroup.c @@ -572,7 +572,7 @@ int __cgroup_bpf_run_filter_skb(struct sock *sk, bpf_compute_and_save_data_end(skb, &saved_data_end); ret = BPF_PROG_RUN_ARRAY(cgrp->bpf.effective[type], skb, - bpf_prog_run_save_cb); + __bpf_prog_run_save_cb); bpf_restore_data_end(skb, saved_data_end); __skb_pull(skb, offset); skb->sk = save_sk; @@ -718,6 +718,7 @@ cgroup_dev_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog) case BPF_FUNC_trace_printk: if (capable(CAP_SYS_ADMIN)) return bpf_get_trace_printk_proto(); + /* fall through */ default: return NULL; } diff --git a/kernel/bpf/hashtab.c b/kernel/bpf/hashtab.c index 4b7c76765d9d..f9274114c88d 100644 --- a/kernel/bpf/hashtab.c +++ b/kernel/bpf/hashtab.c @@ -686,7 +686,7 @@ static void free_htab_elem(struct bpf_htab *htab, struct htab_elem *l) } if (htab_is_prealloc(htab)) { - pcpu_freelist_push(&htab->freelist, &l->fnode); + __pcpu_freelist_push(&htab->freelist, &l->fnode); } else { atomic_dec(&htab->count); l->htab = htab; @@ -748,7 +748,7 @@ static struct htab_elem *alloc_htab_elem(struct bpf_htab *htab, void *key, } else { struct pcpu_freelist_node *l; - l = pcpu_freelist_pop(&htab->freelist); + l = __pcpu_freelist_pop(&htab->freelist); if (!l) return ERR_PTR(-E2BIG); l_new = container_of(l, struct htab_elem, fnode); diff --git a/kernel/bpf/map_in_map.c b/kernel/bpf/map_in_map.c index 99d243e1ad6e..52378d3e34b3 100644 --- a/kernel/bpf/map_in_map.c +++ b/kernel/bpf/map_in_map.c @@ -12,6 +12,7 @@ struct bpf_map *bpf_map_meta_alloc(int inner_map_ufd) { struct bpf_map *inner_map, *inner_map_meta; + u32 inner_map_meta_size; struct fd f; f = fdget(inner_map_ufd); @@ -36,7 +37,12 @@ struct bpf_map *bpf_map_meta_alloc(int inner_map_ufd) return ERR_PTR(-EINVAL); } - inner_map_meta = kzalloc(sizeof(*inner_map_meta), GFP_USER); + inner_map_meta_size = sizeof(*inner_map_meta); + /* In some cases verifier needs to access beyond just base map. */ + if (inner_map->ops == &array_map_ops) + inner_map_meta_size = sizeof(struct bpf_array); + + inner_map_meta = kzalloc(inner_map_meta_size, GFP_USER); if (!inner_map_meta) { fdput(f); return ERR_PTR(-ENOMEM); @@ -46,9 +52,16 @@ struct bpf_map *bpf_map_meta_alloc(int inner_map_ufd) inner_map_meta->key_size = inner_map->key_size; inner_map_meta->value_size = inner_map->value_size; inner_map_meta->map_flags = inner_map->map_flags; - inner_map_meta->ops = inner_map->ops; inner_map_meta->max_entries = inner_map->max_entries; + /* Misc members not needed in bpf_map_meta_equal() check. */ + inner_map_meta->ops = inner_map->ops; + if (inner_map->ops == &array_map_ops) { + inner_map_meta->unpriv_array = inner_map->unpriv_array; + container_of(inner_map_meta, struct bpf_array, map)->index_mask = + container_of(inner_map, struct bpf_array, map)->index_mask; + } + fdput(f); return inner_map_meta; } diff --git a/kernel/bpf/percpu_freelist.c b/kernel/bpf/percpu_freelist.c index 673fa6fe2d73..0c1b4ba9e90e 100644 --- a/kernel/bpf/percpu_freelist.c +++ b/kernel/bpf/percpu_freelist.c @@ -28,8 +28,8 @@ void pcpu_freelist_destroy(struct pcpu_freelist *s) free_percpu(s->freelist); } -static inline void __pcpu_freelist_push(struct pcpu_freelist_head *head, - struct pcpu_freelist_node *node) +static inline void ___pcpu_freelist_push(struct pcpu_freelist_head *head, + struct pcpu_freelist_node *node) { raw_spin_lock(&head->lock); node->next = head->first; @@ -37,12 +37,22 @@ static inline void __pcpu_freelist_push(struct pcpu_freelist_head *head, raw_spin_unlock(&head->lock); } -void pcpu_freelist_push(struct pcpu_freelist *s, +void __pcpu_freelist_push(struct pcpu_freelist *s, struct pcpu_freelist_node *node) { struct pcpu_freelist_head *head = this_cpu_ptr(s->freelist); - __pcpu_freelist_push(head, node); + ___pcpu_freelist_push(head, node); +} + +void pcpu_freelist_push(struct pcpu_freelist *s, + struct pcpu_freelist_node *node) +{ + unsigned long flags; + + local_irq_save(flags); + __pcpu_freelist_push(s, node); + local_irq_restore(flags); } void pcpu_freelist_populate(struct pcpu_freelist *s, void *buf, u32 elem_size, @@ -63,7 +73,7 @@ void pcpu_freelist_populate(struct pcpu_freelist *s, void *buf, u32 elem_size, for_each_possible_cpu(cpu) { again: head = per_cpu_ptr(s->freelist, cpu); - __pcpu_freelist_push(head, buf); + ___pcpu_freelist_push(head, buf); i++; buf += elem_size; if (i == nr_elems) @@ -74,14 +84,12 @@ again: local_irq_restore(flags); } -struct pcpu_freelist_node *pcpu_freelist_pop(struct pcpu_freelist *s) +struct pcpu_freelist_node *__pcpu_freelist_pop(struct pcpu_freelist *s) { struct pcpu_freelist_head *head; struct pcpu_freelist_node *node; - unsigned long flags; int orig_cpu, cpu; - local_irq_save(flags); orig_cpu = cpu = raw_smp_processor_id(); while (1) { head = per_cpu_ptr(s->freelist, cpu); @@ -89,16 +97,25 @@ struct pcpu_freelist_node *pcpu_freelist_pop(struct pcpu_freelist *s) node = head->first; if (node) { head->first = node->next; - raw_spin_unlock_irqrestore(&head->lock, flags); + raw_spin_unlock(&head->lock); return node; } raw_spin_unlock(&head->lock); cpu = cpumask_next(cpu, cpu_possible_mask); if (cpu >= nr_cpu_ids) cpu = 0; - if (cpu == orig_cpu) { - local_irq_restore(flags); + if (cpu == orig_cpu) return NULL; - } } } + +struct pcpu_freelist_node *pcpu_freelist_pop(struct pcpu_freelist *s) +{ + struct pcpu_freelist_node *ret; + unsigned long flags; + + local_irq_save(flags); + ret = __pcpu_freelist_pop(s); + local_irq_restore(flags); + return ret; +} diff --git a/kernel/bpf/percpu_freelist.h b/kernel/bpf/percpu_freelist.h index 3049aae8ea1e..c3960118e617 100644 --- a/kernel/bpf/percpu_freelist.h +++ b/kernel/bpf/percpu_freelist.h @@ -22,8 +22,12 @@ struct pcpu_freelist_node { struct pcpu_freelist_node *next; }; +/* pcpu_freelist_* do spin_lock_irqsave. */ void pcpu_freelist_push(struct pcpu_freelist *, struct pcpu_freelist_node *); struct pcpu_freelist_node *pcpu_freelist_pop(struct pcpu_freelist *); +/* __pcpu_freelist_* do spin_lock only. caller must disable irqs. */ +void __pcpu_freelist_push(struct pcpu_freelist *, struct pcpu_freelist_node *); +struct pcpu_freelist_node *__pcpu_freelist_pop(struct pcpu_freelist *); void pcpu_freelist_populate(struct pcpu_freelist *s, void *buf, u32 elem_size, u32 nr_elems); int pcpu_freelist_init(struct pcpu_freelist *); diff --git a/kernel/bpf/stackmap.c b/kernel/bpf/stackmap.c index 90daf285de03..d43b14535827 100644 --- a/kernel/bpf/stackmap.c +++ b/kernel/bpf/stackmap.c @@ -180,11 +180,14 @@ static inline int stack_map_parse_build_id(void *page_addr, if (nhdr->n_type == BPF_BUILD_ID && nhdr->n_namesz == sizeof("GNU") && - nhdr->n_descsz == BPF_BUILD_ID_SIZE) { + nhdr->n_descsz > 0 && + nhdr->n_descsz <= BPF_BUILD_ID_SIZE) { memcpy(build_id, note_start + note_offs + ALIGN(sizeof("GNU"), 4) + sizeof(Elf32_Nhdr), - BPF_BUILD_ID_SIZE); + nhdr->n_descsz); + memset(build_id + nhdr->n_descsz, 0, + BPF_BUILD_ID_SIZE - nhdr->n_descsz); return 0; } new_offs = note_offs + sizeof(Elf32_Nhdr) + @@ -260,7 +263,7 @@ static int stack_map_get_build_id(struct vm_area_struct *vma, return -EFAULT; /* page not mapped */ ret = -EINVAL; - page_addr = page_address(page); + page_addr = kmap_atomic(page); ehdr = (Elf32_Ehdr *)page_addr; /* compare magic x7f "ELF" */ @@ -276,6 +279,7 @@ static int stack_map_get_build_id(struct vm_area_struct *vma, else if (ehdr->e_ident[EI_CLASS] == ELFCLASS64) ret = stack_map_get_build_id_64(page_addr, build_id); out: + kunmap_atomic(page_addr); put_page(page); return ret; } @@ -310,6 +314,7 @@ static void stack_map_get_build_id_offset(struct bpf_stack_build_id *id_offs, for (i = 0; i < trace_nr; i++) { id_offs[i].status = BPF_STACK_BUILD_ID_IP; id_offs[i].ip = ips[i]; + memset(id_offs[i].build_id, 0, BPF_BUILD_ID_SIZE); } return; } @@ -320,6 +325,7 @@ static void stack_map_get_build_id_offset(struct bpf_stack_build_id *id_offs, /* per entry fall back to ips */ id_offs[i].status = BPF_STACK_BUILD_ID_IP; id_offs[i].ip = ips[i]; + memset(id_offs[i].build_id, 0, BPF_BUILD_ID_SIZE); continue; } id_offs[i].offset = (vma->vm_pgoff << PAGE_SHIFT) + ips[i] diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c index b155cd17c1bd..8577bb7f8be6 100644 --- a/kernel/bpf/syscall.c +++ b/kernel/bpf/syscall.c @@ -713,8 +713,13 @@ static int map_lookup_elem(union bpf_attr *attr) if (bpf_map_is_dev_bound(map)) { err = bpf_map_offload_lookup_elem(map, key, value); - } else if (map->map_type == BPF_MAP_TYPE_PERCPU_HASH || - map->map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH) { + goto done; + } + + preempt_disable(); + this_cpu_inc(bpf_prog_active); + if (map->map_type == BPF_MAP_TYPE_PERCPU_HASH || + map->map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH) { err = bpf_percpu_hash_copy(map, key, value); } else if (map->map_type == BPF_MAP_TYPE_PERCPU_ARRAY) { err = bpf_percpu_array_copy(map, key, value); @@ -744,7 +749,10 @@ static int map_lookup_elem(union bpf_attr *attr) } rcu_read_unlock(); } + this_cpu_dec(bpf_prog_active); + preempt_enable(); +done: if (err) goto free_value; diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c index f6bc62a9ee8e..56674a7c3778 100644 --- a/kernel/bpf/verifier.c +++ b/kernel/bpf/verifier.c @@ -3103,6 +3103,40 @@ static int retrieve_ptr_limit(const struct bpf_reg_state *ptr_reg, } } +static bool can_skip_alu_sanitation(const struct bpf_verifier_env *env, + const struct bpf_insn *insn) +{ + return env->allow_ptr_leaks || BPF_SRC(insn->code) == BPF_K; +} + +static int update_alu_sanitation_state(struct bpf_insn_aux_data *aux, + u32 alu_state, u32 alu_limit) +{ + /* If we arrived here from different branches with different + * state or limits to sanitize, then this won't work. + */ + if (aux->alu_state && + (aux->alu_state != alu_state || + aux->alu_limit != alu_limit)) + return -EACCES; + + /* Corresponding fixup done in fixup_bpf_calls(). */ + aux->alu_state = alu_state; + aux->alu_limit = alu_limit; + return 0; +} + +static int sanitize_val_alu(struct bpf_verifier_env *env, + struct bpf_insn *insn) +{ + struct bpf_insn_aux_data *aux = cur_aux(env); + + if (can_skip_alu_sanitation(env, insn)) + return 0; + + return update_alu_sanitation_state(aux, BPF_ALU_NON_POINTER, 0); +} + static int sanitize_ptr_alu(struct bpf_verifier_env *env, struct bpf_insn *insn, const struct bpf_reg_state *ptr_reg, @@ -3117,7 +3151,7 @@ static int sanitize_ptr_alu(struct bpf_verifier_env *env, struct bpf_reg_state tmp; bool ret; - if (env->allow_ptr_leaks || BPF_SRC(insn->code) == BPF_K) + if (can_skip_alu_sanitation(env, insn)) return 0; /* We already marked aux for masking from non-speculative @@ -3133,19 +3167,8 @@ static int sanitize_ptr_alu(struct bpf_verifier_env *env, if (retrieve_ptr_limit(ptr_reg, &alu_limit, opcode, off_is_neg)) return 0; - - /* If we arrived here from different branches with different - * limits to sanitize, then this won't work. - */ - if (aux->alu_state && - (aux->alu_state != alu_state || - aux->alu_limit != alu_limit)) + if (update_alu_sanitation_state(aux, alu_state, alu_limit)) return -EACCES; - - /* Corresponding fixup done in fixup_bpf_calls(). */ - aux->alu_state = alu_state; - aux->alu_limit = alu_limit; - do_sim: /* Simulate and find potential out-of-bounds access under * speculative execution from truncation as a result of @@ -3418,6 +3441,8 @@ static int adjust_scalar_min_max_vals(struct bpf_verifier_env *env, s64 smin_val, smax_val; u64 umin_val, umax_val; u64 insn_bitness = (BPF_CLASS(insn->code) == BPF_ALU64) ? 64 : 32; + u32 dst = insn->dst_reg; + int ret; if (insn_bitness == 32) { /* Relevant for 32-bit RSH: Information can propagate towards @@ -3452,6 +3477,11 @@ static int adjust_scalar_min_max_vals(struct bpf_verifier_env *env, switch (opcode) { case BPF_ADD: + ret = sanitize_val_alu(env, insn); + if (ret < 0) { + 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; @@ -3471,6 +3501,11 @@ static int adjust_scalar_min_max_vals(struct bpf_verifier_env *env, dst_reg->var_off = tnum_add(dst_reg->var_off, src_reg.var_off); break; case BPF_SUB: + ret = sanitize_val_alu(env, insn); + if (ret < 0) { + 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 */ diff --git a/kernel/cpu.c b/kernel/cpu.c index 91d5c38eb7e5..d1c6d152da89 100644 --- a/kernel/cpu.c +++ b/kernel/cpu.c @@ -376,9 +376,6 @@ void __weak arch_smt_update(void) { } #ifdef CONFIG_HOTPLUG_SMT enum cpuhp_smt_control cpu_smt_control __read_mostly = CPU_SMT_ENABLED; -EXPORT_SYMBOL_GPL(cpu_smt_control); - -static bool cpu_smt_available __read_mostly; void __init cpu_smt_disable(bool force) { @@ -397,25 +394,11 @@ void __init cpu_smt_disable(bool force) /* * The decision whether SMT is supported can only be done after the full - * CPU identification. Called from architecture code before non boot CPUs - * are brought up. - */ -void __init cpu_smt_check_topology_early(void) -{ - if (!topology_smt_supported()) - cpu_smt_control = CPU_SMT_NOT_SUPPORTED; -} - -/* - * If SMT was disabled by BIOS, detect it here, after the CPUs have been - * brought online. This ensures the smt/l1tf sysfs entries are consistent - * with reality. cpu_smt_available is set to true during the bringup of non - * boot CPUs when a SMT sibling is detected. Note, this may overwrite - * cpu_smt_control's previous setting. + * CPU identification. Called from architecture code. */ void __init cpu_smt_check_topology(void) { - if (!cpu_smt_available) + if (!topology_smt_supported()) cpu_smt_control = CPU_SMT_NOT_SUPPORTED; } @@ -428,18 +411,10 @@ early_param("nosmt", smt_cmdline_disable); static inline bool cpu_smt_allowed(unsigned int cpu) { - if (topology_is_primary_thread(cpu)) + if (cpu_smt_control == CPU_SMT_ENABLED) return true; - /* - * If the CPU is not a 'primary' thread and the booted_once bit is - * set then the processor has SMT support. Store this information - * for the late check of SMT support in cpu_smt_check_topology(). - */ - if (per_cpu(cpuhp_state, cpu).booted_once) - cpu_smt_available = true; - - if (cpu_smt_control == CPU_SMT_ENABLED) + if (topology_is_primary_thread(cpu)) return true; /* @@ -2090,10 +2065,8 @@ static int cpuhp_smt_disable(enum cpuhp_smt_control ctrlval) */ cpuhp_offline_cpu_device(cpu); } - if (!ret) { + if (!ret) cpu_smt_control = ctrlval; - arch_smt_update(); - } cpu_maps_update_done(); return ret; } @@ -2104,7 +2077,6 @@ static int cpuhp_smt_enable(void) cpu_maps_update_begin(); cpu_smt_control = CPU_SMT_ENABLED; - arch_smt_update(); for_each_present_cpu(cpu) { /* Skip online CPUs and CPUs on offline nodes */ if (cpu_online(cpu) || !node_online(cpu_to_node(cpu))) diff --git a/kernel/dma/swiotlb.c b/kernel/dma/swiotlb.c index d6361776dc5c..1fb6fd68b9c7 100644 --- a/kernel/dma/swiotlb.c +++ b/kernel/dma/swiotlb.c @@ -378,6 +378,8 @@ void __init swiotlb_exit(void) memblock_free_late(io_tlb_start, PAGE_ALIGN(io_tlb_nslabs << IO_TLB_SHIFT)); } + io_tlb_start = 0; + io_tlb_end = 0; io_tlb_nslabs = 0; max_segment = 0; } diff --git a/kernel/events/core.c b/kernel/events/core.c index 3cd13a30f732..e5ede6918050 100644 --- a/kernel/events/core.c +++ b/kernel/events/core.c @@ -436,18 +436,18 @@ int perf_proc_update_handler(struct ctl_table *table, int write, void __user *buffer, size_t *lenp, loff_t *ppos) { - int ret = proc_dointvec_minmax(table, write, buffer, lenp, ppos); - - if (ret || !write) - return ret; - + int ret; + int perf_cpu = sysctl_perf_cpu_time_max_percent; /* * If throttling is disabled don't allow the write: */ - if (sysctl_perf_cpu_time_max_percent == 100 || - sysctl_perf_cpu_time_max_percent == 0) + if (write && (perf_cpu == 100 || perf_cpu == 0)) return -EINVAL; + ret = proc_dointvec_minmax(table, write, buffer, lenp, ppos); + if (ret || !write) + return ret; + max_samples_per_tick = DIV_ROUND_UP(sysctl_perf_event_sample_rate, HZ); perf_sample_period_ns = NSEC_PER_SEC / sysctl_perf_event_sample_rate; update_perf_cpu_limits(); diff --git a/kernel/events/ring_buffer.c b/kernel/events/ring_buffer.c index 4a9937076331..309ef5a64af5 100644 --- a/kernel/events/ring_buffer.c +++ b/kernel/events/ring_buffer.c @@ -734,6 +734,9 @@ struct ring_buffer *rb_alloc(int nr_pages, long watermark, int cpu, int flags) size = sizeof(struct ring_buffer); size += nr_pages * sizeof(void *); + if (order_base_2(size) >= MAX_ORDER) + goto fail; + rb = kzalloc(size, GFP_KERNEL); if (!rb) goto fail; diff --git a/kernel/exit.c b/kernel/exit.c index 2d14979577ee..2639a30a8aa5 100644 --- a/kernel/exit.c +++ b/kernel/exit.c @@ -307,7 +307,7 @@ void rcuwait_wake_up(struct rcuwait *w) * MB (A) MB (B) * [L] cond [L] tsk */ - smp_rmb(); /* (B) */ + smp_mb(); /* (B) */ /* * Avoid using task_rcu_dereference() magic as long as we are careful, @@ -558,12 +558,14 @@ static struct task_struct *find_alive_thread(struct task_struct *p) return NULL; } -static struct task_struct *find_child_reaper(struct task_struct *father) +static struct task_struct *find_child_reaper(struct task_struct *father, + struct list_head *dead) __releases(&tasklist_lock) __acquires(&tasklist_lock) { struct pid_namespace *pid_ns = task_active_pid_ns(father); struct task_struct *reaper = pid_ns->child_reaper; + struct task_struct *p, *n; if (likely(reaper != father)) return reaper; @@ -579,6 +581,12 @@ static struct task_struct *find_child_reaper(struct task_struct *father) panic("Attempted to kill init! exitcode=0x%08x\n", father->signal->group_exit_code ?: father->exit_code); } + + list_for_each_entry_safe(p, n, dead, ptrace_entry) { + list_del_init(&p->ptrace_entry); + release_task(p); + } + zap_pid_ns_processes(pid_ns); write_lock_irq(&tasklist_lock); @@ -668,7 +676,7 @@ static void forget_original_parent(struct task_struct *father, exit_ptrace(father, dead); /* Can drop and reacquire tasklist_lock */ - reaper = find_child_reaper(father); + reaper = find_child_reaper(father, dead); if (list_empty(&father->children)) return; @@ -866,6 +874,7 @@ void __noreturn do_exit(long code) exit_task_namespaces(tsk); exit_task_work(tsk); exit_thread(tsk); + exit_umh(tsk); /* * Flush inherited counters to the parent - before the parent diff --git a/kernel/fork.c b/kernel/fork.c index a60459947f18..b69248e6f0e0 100644 --- a/kernel/fork.c +++ b/kernel/fork.c @@ -217,6 +217,7 @@ static unsigned long *alloc_thread_stack_node(struct task_struct *tsk, int node) memset(s->addr, 0, THREAD_SIZE); tsk->stack_vm_area = s; + tsk->stack = s->addr; return s->addr; } @@ -1833,8 +1834,6 @@ static __latent_entropy struct task_struct *copy_process( posix_cpu_timers_init(p); - p->start_time = ktime_get_ns(); - p->real_start_time = ktime_get_boot_ns(); p->io_context = NULL; audit_set_context(p, NULL); cgroup_fork(p); @@ -2001,6 +2000,17 @@ static __latent_entropy struct task_struct *copy_process( goto bad_fork_free_pid; /* + * From this point on we must avoid any synchronous user-space + * communication until we take the tasklist-lock. In particular, we do + * not want user-space to be able to predict the process start-time by + * stalling fork(2) after we recorded the start_time but before it is + * visible to the system. + */ + + p->start_time = ktime_get_ns(); + p->real_start_time = ktime_get_boot_ns(); + + /* * Make it visible to the rest of the system, but dont wake it up yet. * Need tasklist lock for parent etc handling! */ diff --git a/kernel/futex.c b/kernel/futex.c index be3bff2315ff..a0514e01c3eb 100644 --- a/kernel/futex.c +++ b/kernel/futex.c @@ -1452,11 +1452,7 @@ static void mark_wake_futex(struct wake_q_head *wake_q, struct futex_q *q) if (WARN(q->pi_state || q->rt_waiter, "refusing to wake PI futex\n")) return; - /* - * Queue the task for later wakeup for after we've released - * the hb->lock. wake_q_add() grabs reference to p. - */ - wake_q_add(wake_q, p); + get_task_struct(p); __unqueue_futex(q); /* * The waiting task can free the futex_q as soon as q->lock_ptr = NULL @@ -1466,6 +1462,13 @@ static void mark_wake_futex(struct wake_q_head *wake_q, struct futex_q *q) * plist_del in __unqueue_futex(). */ smp_store_release(&q->lock_ptr, NULL); + + /* + * Queue the task for later wakeup for after we've released + * the hb->lock. wake_q_add() grabs reference to p. + */ + wake_q_add(wake_q, p); + put_task_struct(p); } /* @@ -2218,11 +2221,11 @@ static inline struct futex_hash_bucket *queue_lock(struct futex_q *q) * decrement the counter at queue_unlock() when some error has * occurred and we don't end up adding the task to the list. */ - hb_waiters_inc(hb); + hb_waiters_inc(hb); /* implies smp_mb(); (A) */ q->lock_ptr = &hb->lock; - spin_lock(&hb->lock); /* implies smp_mb(); (A) */ + spin_lock(&hb->lock); return hb; } @@ -2858,35 +2861,39 @@ retry_private: * and BUG when futex_unlock_pi() interleaves with this. * * Therefore acquire wait_lock while holding hb->lock, but drop the - * latter before calling rt_mutex_start_proxy_lock(). This still fully - * serializes against futex_unlock_pi() as that does the exact same - * lock handoff sequence. + * latter before calling __rt_mutex_start_proxy_lock(). This + * interleaves with futex_unlock_pi() -- which does a similar lock + * handoff -- such that the latter can observe the futex_q::pi_state + * before __rt_mutex_start_proxy_lock() is done. */ raw_spin_lock_irq(&q.pi_state->pi_mutex.wait_lock); spin_unlock(q.lock_ptr); + /* + * __rt_mutex_start_proxy_lock() unconditionally enqueues the @rt_waiter + * such that futex_unlock_pi() is guaranteed to observe the waiter when + * it sees the futex_q::pi_state. + */ ret = __rt_mutex_start_proxy_lock(&q.pi_state->pi_mutex, &rt_waiter, current); raw_spin_unlock_irq(&q.pi_state->pi_mutex.wait_lock); if (ret) { if (ret == 1) ret = 0; - - spin_lock(q.lock_ptr); - goto no_block; + goto cleanup; } - if (unlikely(to)) hrtimer_start_expires(&to->timer, HRTIMER_MODE_ABS); ret = rt_mutex_wait_proxy_lock(&q.pi_state->pi_mutex, to, &rt_waiter); +cleanup: spin_lock(q.lock_ptr); /* - * If we failed to acquire the lock (signal/timeout), we must + * If we failed to acquire the lock (deadlock/signal/timeout), we must * first acquire the hb->lock before removing the lock from the - * rt_mutex waitqueue, such that we can keep the hb and rt_mutex - * wait lists consistent. + * rt_mutex waitqueue, such that we can keep the hb and rt_mutex wait + * lists consistent. * * In particular; it is important that futex_unlock_pi() can not * observe this inconsistency. @@ -3010,6 +3017,10 @@ retry: * there is no point where we hold neither; and therefore * wake_futex_pi() must observe a state consistent with what we * observed. + * + * In particular; this forces __rt_mutex_start_proxy() to + * complete such that we're guaranteed to observe the + * rt_waiter. Also see the WARN in wake_futex_pi(). */ raw_spin_lock_irq(&pi_state->pi_mutex.wait_lock); spin_unlock(&hb->lock); diff --git a/kernel/irq/irqdesc.c b/kernel/irq/irqdesc.c index ee062b7939d3..ef8ad36cadcf 100644 --- a/kernel/irq/irqdesc.c +++ b/kernel/irq/irqdesc.c @@ -457,7 +457,7 @@ static int alloc_descs(unsigned int start, unsigned int cnt, int node, /* Validate affinity mask(s) */ if (affinity) { - for (i = 0; i < cnt; i++, i++) { + for (i = 0; i < cnt; i++) { if (cpumask_empty(&affinity[i].mask)) return -EINVAL; } diff --git a/kernel/irq/manage.c b/kernel/irq/manage.c index a4888ce4667a..84b54a17b95d 100644 --- a/kernel/irq/manage.c +++ b/kernel/irq/manage.c @@ -393,6 +393,9 @@ int irq_setup_affinity(struct irq_desc *desc) } cpumask_and(&mask, cpu_online_mask, set); + if (cpumask_empty(&mask)) + cpumask_copy(&mask, cpu_online_mask); + if (node != NUMA_NO_NODE) { const struct cpumask *nodemask = cpumask_of_node(node); diff --git a/kernel/locking/rtmutex.c b/kernel/locking/rtmutex.c index 581edcc63c26..978d63a8261c 100644 --- a/kernel/locking/rtmutex.c +++ b/kernel/locking/rtmutex.c @@ -1726,12 +1726,33 @@ void rt_mutex_proxy_unlock(struct rt_mutex *lock, rt_mutex_set_owner(lock, NULL); } +/** + * __rt_mutex_start_proxy_lock() - Start lock acquisition for another task + * @lock: the rt_mutex to take + * @waiter: the pre-initialized rt_mutex_waiter + * @task: the task to prepare + * + * Starts the rt_mutex acquire; it enqueues the @waiter and does deadlock + * detection. It does not wait, see rt_mutex_wait_proxy_lock() for that. + * + * NOTE: does _NOT_ remove the @waiter on failure; must either call + * rt_mutex_wait_proxy_lock() or rt_mutex_cleanup_proxy_lock() after this. + * + * Returns: + * 0 - task blocked on lock + * 1 - acquired the lock for task, caller should wake it up + * <0 - error + * + * Special API call for PI-futex support. + */ int __rt_mutex_start_proxy_lock(struct rt_mutex *lock, struct rt_mutex_waiter *waiter, struct task_struct *task) { int ret; + lockdep_assert_held(&lock->wait_lock); + if (try_to_take_rt_mutex(lock, task, NULL)) return 1; @@ -1749,9 +1770,6 @@ int __rt_mutex_start_proxy_lock(struct rt_mutex *lock, ret = 0; } - if (unlikely(ret)) - remove_waiter(lock, waiter); - debug_rt_mutex_print_deadlock(waiter); return ret; @@ -1763,12 +1781,18 @@ int __rt_mutex_start_proxy_lock(struct rt_mutex *lock, * @waiter: the pre-initialized rt_mutex_waiter * @task: the task to prepare * + * Starts the rt_mutex acquire; it enqueues the @waiter and does deadlock + * detection. It does not wait, see rt_mutex_wait_proxy_lock() for that. + * + * NOTE: unlike __rt_mutex_start_proxy_lock this _DOES_ remove the @waiter + * on failure. + * * Returns: * 0 - task blocked on lock * 1 - acquired the lock for task, caller should wake it up * <0 - error * - * Special API call for FUTEX_REQUEUE_PI support. + * Special API call for PI-futex support. */ int rt_mutex_start_proxy_lock(struct rt_mutex *lock, struct rt_mutex_waiter *waiter, @@ -1778,6 +1802,8 @@ int rt_mutex_start_proxy_lock(struct rt_mutex *lock, raw_spin_lock_irq(&lock->wait_lock); ret = __rt_mutex_start_proxy_lock(lock, waiter, task); + if (unlikely(ret)) + remove_waiter(lock, waiter); raw_spin_unlock_irq(&lock->wait_lock); return ret; @@ -1845,7 +1871,8 @@ int rt_mutex_wait_proxy_lock(struct rt_mutex *lock, * @lock: the rt_mutex we were woken on * @waiter: the pre-initialized rt_mutex_waiter * - * Attempt to clean up after a failed rt_mutex_wait_proxy_lock(). + * Attempt to clean up after a failed __rt_mutex_start_proxy_lock() or + * rt_mutex_wait_proxy_lock(). * * Unless we acquired the lock; we're still enqueued on the wait-list and can * in fact still be granted ownership until we're removed. Therefore we can diff --git a/kernel/locking/rwsem-xadd.c b/kernel/locking/rwsem-xadd.c index 09b180063ee1..50d9af615dc4 100644 --- a/kernel/locking/rwsem-xadd.c +++ b/kernel/locking/rwsem-xadd.c @@ -198,15 +198,22 @@ static void __rwsem_mark_wake(struct rw_semaphore *sem, woken++; tsk = waiter->task; - wake_q_add(wake_q, tsk); + get_task_struct(tsk); list_del(&waiter->list); /* - * Ensure that the last operation is setting the reader + * Ensure calling get_task_struct() before setting the reader * waiter to nil such that rwsem_down_read_failed() cannot * race with do_exit() by always holding a reference count * to the task to wakeup. */ smp_store_release(&waiter->task, NULL); + /* + * Ensure issuing the wakeup (either by us or someone else) + * after setting the reader waiter to nil. + */ + wake_q_add(wake_q, tsk); + /* wake_q_add() already take the task ref */ + put_task_struct(tsk); } adjustment = woken * RWSEM_ACTIVE_READ_BIAS - adjustment; diff --git a/kernel/relay.c b/kernel/relay.c index 04f248644e06..9e0f52375487 100644 --- a/kernel/relay.c +++ b/kernel/relay.c @@ -428,6 +428,8 @@ static struct dentry *relay_create_buf_file(struct rchan *chan, dentry = chan->cb->create_buf_file(tmpname, chan->parent, S_IRUSR, buf, &chan->is_global); + if (IS_ERR(dentry)) + dentry = NULL; kfree(tmpname); @@ -461,7 +463,7 @@ static struct rchan_buf *relay_open_buf(struct rchan *chan, unsigned int cpu) dentry = chan->cb->create_buf_file(NULL, NULL, S_IRUSR, buf, &chan->is_global); - if (WARN_ON(dentry)) + if (IS_ERR_OR_NULL(dentry)) goto free_buf; } diff --git a/kernel/sched/core.c b/kernel/sched/core.c index a674c7db2f29..d8d76a65cfdd 100644 --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -396,6 +396,18 @@ static bool set_nr_if_polling(struct task_struct *p) #endif #endif +/** + * wake_q_add() - queue a wakeup for 'later' waking. + * @head: the wake_q_head to add @task to + * @task: the task to queue for 'later' wakeup + * + * Queue a task for later wakeup, most likely by the wake_up_q() call in the + * same context, _HOWEVER_ this is not guaranteed, the wakeup can come + * instantly. + * + * This function must be used as-if it were wake_up_process(); IOW the task + * must be ready to be woken at this location. + */ void wake_q_add(struct wake_q_head *head, struct task_struct *task) { struct wake_q_node *node = &task->wake_q; @@ -405,10 +417,11 @@ void wake_q_add(struct wake_q_head *head, struct task_struct *task) * its already queued (either by us or someone else) and will get the * wakeup due to that. * - * This cmpxchg() executes a full barrier, which pairs with the full - * barrier executed by the wakeup in wake_up_q(). + * In order to ensure that a pending wakeup will observe our pending + * state, even in the failed case, an explicit smp_mb() must be used. */ - if (cmpxchg(&node->next, NULL, WAKE_Q_TAIL)) + smp_mb__before_atomic(); + if (cmpxchg_relaxed(&node->next, NULL, WAKE_Q_TAIL)) return; get_task_struct(task); diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c index 50aa2aba69bd..310d0637fe4b 100644 --- a/kernel/sched/fair.c +++ b/kernel/sched/fair.c @@ -5980,6 +5980,7 @@ static inline int find_idlest_cpu(struct sched_domain *sd, struct task_struct *p #ifdef CONFIG_SCHED_SMT DEFINE_STATIC_KEY_FALSE(sched_smt_present); +EXPORT_SYMBOL_GPL(sched_smt_present); static inline void set_idle_cores(int cpu, int val) { diff --git a/kernel/sched/psi.c b/kernel/sched/psi.c index fe24de3fbc93..c3484785b179 100644 --- a/kernel/sched/psi.c +++ b/kernel/sched/psi.c @@ -124,6 +124,7 @@ * sampling of the aggregate task states would be. */ +#include "../workqueue_internal.h" #include <linux/sched/loadavg.h> #include <linux/seq_file.h> #include <linux/proc_fs.h> @@ -480,9 +481,6 @@ static void psi_group_change(struct psi_group *group, int cpu, groupc->tasks[t]++; write_seqcount_end(&groupc->seq); - - if (!delayed_work_pending(&group->clock_work)) - schedule_delayed_work(&group->clock_work, PSI_FREQ); } static struct psi_group *iterate_groups(struct task_struct *task, void **iter) @@ -513,6 +511,7 @@ void psi_task_change(struct task_struct *task, int clear, int set) { int cpu = task_cpu(task); struct psi_group *group; + bool wake_clock = true; void *iter = NULL; if (!task->pid) @@ -530,8 +529,22 @@ void psi_task_change(struct task_struct *task, int clear, int set) task->psi_flags &= ~clear; task->psi_flags |= set; - while ((group = iterate_groups(task, &iter))) + /* + * Periodic aggregation shuts off if there is a period of no + * task changes, so we wake it back up if necessary. However, + * don't do this if the task change is the aggregation worker + * itself going to sleep, or we'll ping-pong forever. + */ + if (unlikely((clear & TSK_RUNNING) && + (task->flags & PF_WQ_WORKER) && + wq_worker_last_func(task) == psi_update_work)) + wake_clock = false; + + while ((group = iterate_groups(task, &iter))) { psi_group_change(group, cpu, clear, set); + if (wake_clock && !delayed_work_pending(&group->clock_work)) + schedule_delayed_work(&group->clock_work, PSI_FREQ); + } } void psi_memstall_tick(struct task_struct *task, int cpu) diff --git a/kernel/seccomp.c b/kernel/seccomp.c index d7f538847b84..e815781ed751 100644 --- a/kernel/seccomp.c +++ b/kernel/seccomp.c @@ -976,6 +976,9 @@ static int seccomp_notify_release(struct inode *inode, struct file *file) struct seccomp_filter *filter = file->private_data; struct seccomp_knotif *knotif; + if (!filter) + return 0; + mutex_lock(&filter->notify_lock); /* @@ -1300,6 +1303,7 @@ out: out_put_fd: if (flags & SECCOMP_FILTER_FLAG_NEW_LISTENER) { if (ret < 0) { + listener_f->private_data = NULL; fput(listener_f); put_unused_fd(listener); } else { diff --git a/kernel/signal.c b/kernel/signal.c index e1d7ad8e6ab1..99fa8ff06fd9 100644 --- a/kernel/signal.c +++ b/kernel/signal.c @@ -688,6 +688,48 @@ int dequeue_signal(struct task_struct *tsk, sigset_t *mask, kernel_siginfo_t *in } EXPORT_SYMBOL_GPL(dequeue_signal); +static int dequeue_synchronous_signal(kernel_siginfo_t *info) +{ + struct task_struct *tsk = current; + struct sigpending *pending = &tsk->pending; + struct sigqueue *q, *sync = NULL; + + /* + * Might a synchronous signal be in the queue? + */ + if (!((pending->signal.sig[0] & ~tsk->blocked.sig[0]) & SYNCHRONOUS_MASK)) + return 0; + + /* + * Return the first synchronous signal in the queue. + */ + list_for_each_entry(q, &pending->list, list) { + /* Synchronous signals have a postive si_code */ + if ((q->info.si_code > SI_USER) && + (sigmask(q->info.si_signo) & SYNCHRONOUS_MASK)) { + sync = q; + goto next; + } + } + return 0; +next: + /* + * Check if there is another siginfo for the same signal. + */ + list_for_each_entry_continue(q, &pending->list, list) { + if (q->info.si_signo == sync->info.si_signo) + goto still_pending; + } + + sigdelset(&pending->signal, sync->info.si_signo); + recalc_sigpending(); +still_pending: + list_del_init(&sync->list); + copy_siginfo(info, &sync->info); + __sigqueue_free(sync); + return info->si_signo; +} + /* * Tell a process that it has a new active signal.. * @@ -1057,10 +1099,9 @@ static int __send_signal(int sig, struct kernel_siginfo *info, struct task_struc result = TRACE_SIGNAL_DELIVERED; /* - * Skip useless siginfo allocation for SIGKILL SIGSTOP, - * and kernel threads. + * Skip useless siginfo allocation for SIGKILL and kernel threads. */ - if (sig_kernel_only(sig) || (t->flags & PF_KTHREAD)) + if ((sig == SIGKILL) || (t->flags & PF_KTHREAD)) goto out_set; /* @@ -2394,6 +2435,11 @@ relock: goto relock; } + /* Has this task already been marked for death? */ + ksig->info.si_signo = signr = SIGKILL; + if (signal_group_exit(signal)) + goto fatal; + for (;;) { struct k_sigaction *ka; @@ -2407,7 +2453,15 @@ relock: goto relock; } - signr = dequeue_signal(current, ¤t->blocked, &ksig->info); + /* + * Signals generated by the execution of an instruction + * need to be delivered before any other pending signals + * so that the instruction pointer in the signal stack + * frame points to the faulting instruction. + */ + signr = dequeue_synchronous_signal(&ksig->info); + if (!signr) + signr = dequeue_signal(current, ¤t->blocked, &ksig->info); if (!signr) break; /* will return 0 */ @@ -2489,6 +2543,7 @@ relock: continue; } + fatal: spin_unlock_irq(&sighand->siglock); /* diff --git a/kernel/smp.c b/kernel/smp.c index 163c451af42e..f4cf1b0bb3b8 100644 --- a/kernel/smp.c +++ b/kernel/smp.c @@ -584,8 +584,6 @@ void __init smp_init(void) num_nodes, (num_nodes > 1 ? "s" : ""), num_cpus, (num_cpus > 1 ? "s" : "")); - /* Final decision about SMT support */ - cpu_smt_check_topology(); /* Any cleanup work */ smp_cpus_done(setup_max_cpus); } diff --git a/kernel/sys.c b/kernel/sys.c index a48cbf1414b8..f7eb62eceb24 100644 --- a/kernel/sys.c +++ b/kernel/sys.c @@ -1207,7 +1207,8 @@ DECLARE_RWSEM(uts_sem); /* * Work around broken programs that cannot handle "Linux 3.0". * Instead we map 3.x to 2.6.40+x, so e.g. 3.0 would be 2.6.40 - * And we map 4.x to 2.6.60+x, so 4.0 would be 2.6.60. + * And we map 4.x and later versions to 2.6.60+x, so 4.0/5.0/6.0/... would be + * 2.6.60. */ static int override_release(char __user *release, size_t len) { diff --git a/kernel/time/posix-cpu-timers.c b/kernel/time/posix-cpu-timers.c index 8f0644af40be..80f955210861 100644 --- a/kernel/time/posix-cpu-timers.c +++ b/kernel/time/posix-cpu-timers.c @@ -685,6 +685,7 @@ static int posix_cpu_timer_set(struct k_itimer *timer, int timer_flags, * set up the signal and overrun bookkeeping. */ timer->it.cpu.incr = timespec64_to_ns(&new->it_interval); + timer->it_interval = ns_to_ktime(timer->it.cpu.incr); /* * This acts as a modification timestamp for the timer, diff --git a/kernel/trace/bpf_trace.c b/kernel/trace/bpf_trace.c index 8b068adb9da1..f1a86a0d881d 100644 --- a/kernel/trace/bpf_trace.c +++ b/kernel/trace/bpf_trace.c @@ -1204,22 +1204,12 @@ static int __bpf_probe_register(struct bpf_raw_event_map *btp, struct bpf_prog * int bpf_probe_register(struct bpf_raw_event_map *btp, struct bpf_prog *prog) { - int err; - - mutex_lock(&bpf_event_mutex); - err = __bpf_probe_register(btp, prog); - mutex_unlock(&bpf_event_mutex); - return err; + return __bpf_probe_register(btp, prog); } int bpf_probe_unregister(struct bpf_raw_event_map *btp, struct bpf_prog *prog) { - int err; - - mutex_lock(&bpf_event_mutex); - err = tracepoint_probe_unregister(btp->tp, (void *)btp->bpf_func, prog); - mutex_unlock(&bpf_event_mutex); - return err; + return tracepoint_probe_unregister(btp->tp, (void *)btp->bpf_func, prog); } int bpf_get_perf_event_info(const struct perf_event *event, u32 *prog_id, diff --git a/kernel/umh.c b/kernel/umh.c index 0baa672e023c..d937cbad903a 100644 --- a/kernel/umh.c +++ b/kernel/umh.c @@ -37,6 +37,8 @@ static kernel_cap_t usermodehelper_bset = CAP_FULL_SET; static kernel_cap_t usermodehelper_inheritable = CAP_FULL_SET; static DEFINE_SPINLOCK(umh_sysctl_lock); static DECLARE_RWSEM(umhelper_sem); +static LIST_HEAD(umh_list); +static DEFINE_MUTEX(umh_list_lock); static void call_usermodehelper_freeinfo(struct subprocess_info *info) { @@ -100,10 +102,12 @@ static int call_usermodehelper_exec_async(void *data) commit_creds(new); sub_info->pid = task_pid_nr(current); - if (sub_info->file) + if (sub_info->file) { retval = do_execve_file(sub_info->file, sub_info->argv, sub_info->envp); - else + if (!retval) + current->flags |= PF_UMH; + } else retval = do_execve(getname_kernel(sub_info->path), (const char __user *const __user *)sub_info->argv, (const char __user *const __user *)sub_info->envp); @@ -517,6 +521,11 @@ int fork_usermode_blob(void *data, size_t len, struct umh_info *info) goto out; err = call_usermodehelper_exec(sub_info, UMH_WAIT_EXEC); + if (!err) { + mutex_lock(&umh_list_lock); + list_add(&info->list, &umh_list); + mutex_unlock(&umh_list_lock); + } out: fput(file); return err; @@ -679,6 +688,26 @@ static int proc_cap_handler(struct ctl_table *table, int write, return 0; } +void __exit_umh(struct task_struct *tsk) +{ + struct umh_info *info; + pid_t pid = tsk->pid; + + mutex_lock(&umh_list_lock); + list_for_each_entry(info, &umh_list, list) { + if (info->pid == pid) { + list_del(&info->list); + mutex_unlock(&umh_list_lock); + goto out; + } + } + mutex_unlock(&umh_list_lock); + return; +out: + if (info->cleanup) + info->cleanup(info); +} + struct ctl_table usermodehelper_table[] = { { .procname = "bset", diff --git a/kernel/workqueue.c b/kernel/workqueue.c index 392be4b252f6..fc5d23d752a5 100644 --- a/kernel/workqueue.c +++ b/kernel/workqueue.c @@ -910,6 +910,26 @@ struct task_struct *wq_worker_sleeping(struct task_struct *task) } /** + * wq_worker_last_func - retrieve worker's last work function + * + * Determine the last function a worker executed. This is called from + * the scheduler to get a worker's last known identity. + * + * CONTEXT: + * spin_lock_irq(rq->lock) + * + * Return: + * The last work function %current executed as a worker, NULL if it + * hasn't executed any work yet. + */ +work_func_t wq_worker_last_func(struct task_struct *task) +{ + struct worker *worker = kthread_data(task); + + return worker->last_func; +} + +/** * worker_set_flags - set worker flags and adjust nr_running accordingly * @worker: self * @flags: flags to set @@ -2184,6 +2204,9 @@ __acquires(&pool->lock) if (unlikely(cpu_intensive)) worker_clr_flags(worker, WORKER_CPU_INTENSIVE); + /* tag the worker for identification in schedule() */ + worker->last_func = worker->current_func; + /* we're done with it, release */ hash_del(&worker->hentry); worker->current_work = NULL; diff --git a/kernel/workqueue_internal.h b/kernel/workqueue_internal.h index 66fbb5a9e633..cb68b03ca89a 100644 --- a/kernel/workqueue_internal.h +++ b/kernel/workqueue_internal.h @@ -53,6 +53,9 @@ struct worker { /* used only by rescuers to point to the target workqueue */ struct workqueue_struct *rescue_wq; /* I: the workqueue to rescue */ + + /* used by the scheduler to determine a worker's last known identity */ + work_func_t last_func; }; /** @@ -67,9 +70,10 @@ static inline struct worker *current_wq_worker(void) /* * Scheduler hooks for concurrency managed workqueue. Only to be used from - * sched/core.c and workqueue.c. + * sched/ and workqueue.c. */ void wq_worker_waking_up(struct task_struct *task, int cpu); struct task_struct *wq_worker_sleeping(struct task_struct *task); +work_func_t wq_worker_last_func(struct task_struct *task); #endif /* _KERNEL_WORKQUEUE_INTERNAL_H */ |