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--- subversion-1.10.2/subversion/libsvn_repos/authz.c	
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+++ subversion-1.10.2/subversion/libsvn_repos/authz.c	
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@@ -130,6 +130,30 @@
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 static svn_object_pool__t *filtered_pool = NULL;
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 static svn_atomic_t authz_pool_initialized = FALSE;
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+/*
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+ * Ensure that we will initialize authz again if the pool which
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+ * our authz caches depend on is cleared.
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+ *
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+ * HTTPD may run pre/post config hooks multiple times and clear
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+ * its global configuration pool which our authz pools depend on.
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+ * This happens in a non-threaded context during HTTPD's intialization
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+ * and HTTPD's main loop, so it is safe to reset static variables here.
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+ * (And any applications which cleared this pool while SVN threads
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+ * were running would crash no matter what.)
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+ *
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+ * See issue #4880, "Use-after-free of object-pools in
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+ * subversion/libsvn_repos/authz.c when used as httpd module"
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+ */
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+static apr_status_t
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+deinit_authz(void *data)
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+{
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+  /* The two object pools run their own cleanup handlers. */
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+  authz_pool = NULL;
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+  filtered_pool = NULL;
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+  authz_pool_initialized = FALSE;
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+  return APR_SUCCESS;
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+}
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+
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 /* Implements svn_atomic__err_init_func_t. */
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 static svn_error_t *
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 synchronized_authz_initialize(void *baton, apr_pool_t *pool)
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@@ -143,6 +167,7 @@
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   SVN_ERR(svn_object_pool__create(&authz_pool, multi_threaded, pool));
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   SVN_ERR(svn_object_pool__create(&filtered_pool, multi_threaded, pool));
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+  apr_pool_cleanup_register(pool, NULL, deinit_authz, apr_pool_cleanup_null);
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   return SVN_NO_ERROR;
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 }
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