1 files changed, 63 insertions, 14 deletions

diff --git a/crypto/algapi.c b/crypto/algapi.c
index 6a98076d9d2a..feb77e4bbb48 100644
--- a/crypto/algapi.c
+++ b/crypto/algapi.c
@@ -81,16 +81,35 @@ static void crypto_destroy_instance(struct crypto_alg *alg)
         crypto_tmpl_put(tmpl);
 }
 
+static struct list_head *crypto_more_spawns(struct crypto_alg *alg,
+                                            struct list_head *stack,
+                                            struct list_head *top,
+                                            struct list_head *secondary_spawns)
+{
+        struct crypto_spawn *spawn, *n;
+
+        if (list_empty(stack))
+                return NULL;
+
+        spawn = list_first_entry(stack, struct crypto_spawn, list);
+        n = list_entry(spawn->list.next, struct crypto_spawn, list);
+
+        if (spawn->alg && &n->list != stack && !n->alg)
+                n->alg = (n->list.next == stack) ? alg :
+                         &list_entry(n->list.next, struct crypto_spawn,
+                                     list)->inst->alg;
+
+        list_move(&spawn->list, secondary_spawns);
+
+        return &n->list == stack ? top : &n->inst->alg.cra_users;
+}
+
 static void crypto_remove_spawn(struct crypto_spawn *spawn,
-                                struct list_head *list,
-                                struct list_head *secondary_spawns)
+                                struct list_head *list)
 {
         struct crypto_instance *inst = spawn->inst;
         struct crypto_template *tmpl = inst->tmpl;
 
-        list_del_init(&spawn->list);
-        spawn->alg = NULL;
-
         if (crypto_is_dead(&inst->alg))
                 return;
 
@@ -106,25 +125,55 @@ static void crypto_remove_spawn(struct crypto_spawn *spawn,
         hlist_del(&inst->list);
         inst->alg.cra_destroy = crypto_destroy_instance;
 
-        list_splice(&inst->alg.cra_users, secondary_spawns);
+        BUG_ON(!list_empty(&inst->alg.cra_users));
 }
 
-static void crypto_remove_spawns(struct list_head *spawns,
-                                 struct list_head *list, u32 new_type)
+static void crypto_remove_spawns(struct crypto_alg *alg,
+                                 struct list_head *list,
+                                 struct crypto_alg *nalg)
 {
+        u32 new_type = (nalg ?: alg)->cra_flags;
         struct crypto_spawn *spawn, *n;
         LIST_HEAD(secondary_spawns);
+        struct list_head *spawns;
+        LIST_HEAD(stack);
+        LIST_HEAD(top);
 
+        spawns = &alg->cra_users;
         list_for_each_entry_safe(spawn, n, spawns, list) {
                 if ((spawn->alg->cra_flags ^ new_type) & spawn->mask)
                         continue;
 
-                crypto_remove_spawn(spawn, list, &secondary_spawns);
+                list_move(&spawn->list, &top);
         }
 
-        while (!list_empty(&secondary_spawns)) {
-                list_for_each_entry_safe(spawn, n, &secondary_spawns, list)
-                        crypto_remove_spawn(spawn, list, &secondary_spawns);
+        spawns = ⊤
+        do {
+                while (!list_empty(spawns)) {
+                        struct crypto_instance *inst;
+
+                        spawn = list_first_entry(spawns, struct crypto_spawn,
+                                                 list);
+                        inst = spawn->inst;
+
+                        BUG_ON(&inst->alg == alg);
+
+                        list_move(&spawn->list, &stack);
+
+                        if (&inst->alg == nalg)
+                                break;
+
+                        spawn->alg = NULL;
+                        spawns = &inst->alg.cra_users;
+                }
+        } while ((spawns = crypto_more_spawns(alg, &stack, &top,
+                                              &secondary_spawns)));
+
+        list_for_each_entry_safe(spawn, n, &secondary_spawns, list) {
+                if (spawn->alg)
+                        list_move(&spawn->list, &spawn->alg->cra_users);
+                else
+                        crypto_remove_spawn(spawn, list);
         }
 }
 
@@ -258,7 +307,7 @@ found:
                     q->cra_priority > alg->cra_priority)
                         continue;
 
-                crypto_remove_spawns(&q->cra_users, &list, alg->cra_flags);
+                crypto_remove_spawns(q, &list, alg);
         }
 
 complete:
@@ -330,7 +379,7 @@ static int crypto_remove_alg(struct crypto_alg *alg, struct list_head *list)
 
         crypto_notify(CRYPTO_MSG_ALG_UNREGISTER, alg);
         list_del_init(&alg->cra_list);
-        crypto_remove_spawns(&alg->cra_users, list, alg->cra_flags);
+        crypto_remove_spawns(alg, list, NULL);
 
         return 0;
 }