18 files changed, 180 insertions, 45 deletions

diff --git a/kernel/bpf/btf.c b/kernel/bpf/btf.c
index 715f9fcf4712..befe570be5ba 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,
@@ -2001,12 +2001,12 @@ 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..ab612fe9862f 100644
--- a/kernel/bpf/cgroup.c
+++ b/kernel/bpf/cgroup.c
@@ -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/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/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/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/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/exit.c b/kernel/exit.c
index 2d14979577ee..3fb7be001964 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,
@@ -866,6 +866,7 @@ 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..fdd312da0992 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);
 }
 
 /*
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/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/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/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/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/trace_kprobe.c b/kernel/trace/trace_kprobe.c
index 5c19b8c41c7e..d5fb09ebba8b 100644
--- a/kernel/trace/trace_kprobe.c
+++ b/kernel/trace/trace_kprobe.c
@@ -607,11 +607,17 @@ static int trace_kprobe_create(int argc, const char *argv[])
         char buf[MAX_EVENT_NAME_LEN];
         unsigned int flags = TPARG_FL_KERNEL;
 
-        /* argc must be >= 1 */
-        if (argv[0][0] == 'r') {
+        switch (argv[0][0]) {
+        case 'r':
                 is_return = true;
                 flags |= TPARG_FL_RETURN;
-        } else if (argv[0][0] != 'p' || argc < 2)
+                break;
+        case 'p':
+                break;
+        default:
+                return -ECANCELED;
+        }
+        if (argc < 2)
                 return -ECANCELED;
 
         event = strchr(&argv[0][1], ':');
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",