BUG/MEDIUM: cache: use key=0 as a condition for freeing

The cache was trying to remove objects from the tree while they were
already removed from it. We set the key to 0 as a check for not trying
to remove the object from the tree when we are still using the object.

diff --git a/src/cache.c b/src/cache.c
index 0d726c72913a5a9f81d3843ee2959b5a366ec6b3..ed244cb0a6e9ef6e75b0d03a52e56e3caa256d1b 100644 (file)
--- a/src/cache.c
+++ b/src/cache.c
@@ -81,10 +81,12 @@ struct cache_entry *entry_exist(struct cache *cache, struct cache_entry *new_ent
                return NULL;
 
        entry = eb32_entry(node, struct cache_entry, eb);
-       if (entry->expire > now.tv_sec)
+       if (entry->expire > now.tv_sec) {
                return entry;
-       else
+       } else {
                eb32_delete(node);
+               entry->eb.key = 0;
+       }
        return NULL;
 
 }
@@ -149,6 +151,7 @@ cache_store_http_forward_data(struct stream *s, struct filter *filter,
 {
        struct cache_st *st = filter->ctx;
        struct shared_context *shctx = shctx_ptr((struct cache *)filter->config->conf);
+       struct cache_entry *object;
        int ret;
 
        /*
@@ -173,9 +176,11 @@ cache_store_http_forward_data(struct stream *s, struct filter *filter,
                        /* disable buffering if too much data (never greater than a buffer size */
                        if (len - st->hdrs_len > global.tune.bufsize - global.tune.maxrewrite - st->first_block->len) {
                          disable_cache:
+                               object = (struct cache_entry *)st->first_block->data;
                                filter->ctx = NULL; /* disable cache  */
                                shctx_lock(shctx);
                                shctx_row_dec_hot(shctx, st->first_block);
+                               object->eb.key = 0;
                                shctx_unlock(shctx);
                                pool_free2(pool2_cache_st, st);
                        } else {
@@ -221,11 +226,10 @@ cache_store_http_end(struct stream *s, struct filter *filter,
                 * doesn't, the blocks will be reused anyway */
 
                shctx_lock(shctx);
-               eb32_insert(&cache->entries, &object->eb);
-               shctx_unlock(shctx);
-
+               if (eb32_insert(&cache->entries, &object->eb) != &object->eb) {
+                       object->eb.key = 0;
+               }
                /* remove from the hotlist */
-               shctx_lock(shctx);
                shctx_row_dec_hot(shctx, st->first_block);
                shctx_unlock(shctx);
 
@@ -343,7 +347,10 @@ static void cache_free_blocks(struct shared_block *first, struct shared_block *b
 {
        if (first == block) {
                struct cache_entry *object = (struct cache_entry *)first->data;
-               eb32_delete(&object->eb);
+               if (object->eb.key) {
+                       eb32_delete(&object->eb);
+                       object->eb.key = 0;
+               }
        }
 }
 
@@ -443,6 +450,7 @@ enum act_return http_action_store_cache(struct act_rule *rule, struct proxy *px,
                                        if (entry_exist((struct cache *)rule->arg.act.p[0], object)) {
                                                shctx_unlock(shctx);
                                                if (filter->ctx) {
+                                                       object->eb.key = 0;
                                                        pool_free2(pool2_cache_st, filter->ctx);
                                                        filter->ctx = NULL;
                                                }
@@ -463,7 +471,11 @@ enum act_return http_action_store_cache(struct act_rule *rule, struct proxy *px,
 out:
        /* if does not cache */
        if (first) {
+               object = (struct cache_entry *)first->data;
+
                shctx_lock(shctx);
+               first->len = 0;
+               object->eb.key = 0;
                shctx_row_dec_hot(shctx, first);
                shctx_unlock(shctx);
        }