TOMOYO: Simplify garbage collector.

When TOMOYO started using garbage collector at commit 847b173e "TOMOYO: Add
garbage collector.", we waited for close() before kfree(). Thus, elements to be
kfree()d were queued up using tomoyo_gc_list list.

But it turned out that tomoyo_element_linked_by_gc() tends to choke garbage
collector when certain pattern of entries are queued.

Since garbage collector is no longer waiting for close() since commit 2e503bbb
"TOMOYO: Fix lockdep warning.", we can remove tomoyo_gc_list list and
tomoyo_element_linked_by_gc() by doing sequential processing.

Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: James Morris <jmorris@namei.org>

1 files changed, 5 insertions, 2 deletions

diff --git a/security/tomoyo/common.h b/security/tomoyo/common.h
index 1a19ad3e67ea..a0212fbf60fb 100644
--- a/security/tomoyo/common.h
+++ b/security/tomoyo/common.h
@@ -52,6 +52,9 @@
 
 #define TOMOYO_EXEC_TMPSIZE     4096
 
+/* Garbage collector is trying to kfree() this element. */
+#define TOMOYO_GC_IN_PROGRESS -1
+
 /* Profile number is an integer between 0 and 255. */
 #define TOMOYO_MAX_PROFILES 256
 
@@ -398,7 +401,7 @@ enum tomoyo_pref_index {
 /* Common header for holding ACL entries. */
 struct tomoyo_acl_head {
         struct list_head list;
-        bool is_deleted;
+        s8 is_deleted; /* true or false or TOMOYO_GC_IN_PROGRESS */
 } __packed;
 
 /* Common header for shared entries. */
@@ -665,7 +668,7 @@ struct tomoyo_condition {
 struct tomoyo_acl_info {
         struct list_head list;
         struct tomoyo_condition *cond; /* Maybe NULL. */
-        bool is_deleted;
+        s8 is_deleted; /* true or false or TOMOYO_GC_IN_PROGRESS */
         u8 type; /* One of values in "enum tomoyo_acl_entry_type_index". */
 } __packed;