From c5e3bb7917689bc9ed54fee23a143144fade802d Mon Sep 17 00:00:00 2001
From: Jon Santmyer <jon@jonsantmyer.com>
Date: Sat, 10 Oct 2026 08:24:49 -0400
Subject: add check for pcb retype for correct rootdir layout

---
 api/syscall.h         | 2 ++
 arch/x86_64/hal/obj.c | 5 +++++
 hal/obj.h             | 3 +++
 proc/process.c        | 2 +-
 sys/objdir.c          | 7 +++++++
 sys/objdir.h          | 2 ++
 sys/syscall_untyped.c | 7 +++++++
 7 files changed, 27 insertions(+), 1 deletion(-)

diff --git a/api/syscall.h b/api/syscall.h
index 6b10569..54ff267 100644
--- a/api/syscall.h
+++ b/api/syscall.h
@@ -179,12 +179,14 @@ struct syscall_region_merge
 enum
 {
     _SYSCALL_PCB_NONE = 0,
+    SYSCALL_PCB_PID,
     SYSCALL_PCB_YIELD,
     SYSCALL_PCB_SEND,
     SYSCALL_PCB_RECV,
     SYSCALL_PCB_READY,
 };
 
+#define SYSCALL_PERM_PCB_PID (JOVE_PERM_READ)
 #define SYSCALL_PERM_PCB_YIELD (JOVE_PERM_WRITE)
 #define SYSCALL_PERM_PCB_SEND (JOVE_PERM_WRITE)
 #define SYSCALL_PERM_PCB_RECV (JOVE_PERM_WRITE)
diff --git a/arch/x86_64/hal/obj.c b/arch/x86_64/hal/obj.c
index b3658b2..d6c9a80 100644
--- a/arch/x86_64/hal/obj.c
+++ b/arch/x86_64/hal/obj.c
@@ -79,3 +79,8 @@ obj_setvalue(jove_owned_obj_t *obj, uintmax_t value)
     obj->locked.value = value & 0x00007FFFFFFFFFFFULL;
 }
 
+bool 
+obj_compare(jove_obj_t *a, jove_obj_t *b)
+{
+    return a->data == b->data;
+}
diff --git a/hal/obj.h b/hal/obj.h
index 5a48eb2..61ba968 100644
--- a/hal/obj.h
+++ b/hal/obj.h
@@ -1,3 +1,4 @@
+#include <stdbool.h>
 #ifndef _JOVE_HAL_OBJ_H
 #define _JOVE_HAL_OBJ_H 1
 
@@ -33,4 +34,6 @@ void obj_settype(jove_owned_obj_t *obj, uint8_t type);
 uintmax_t obj_getvalue(jove_owned_obj_t *obj);
 void obj_setvalue(jove_owned_obj_t *obj, uintmax_t value);
 
+bool obj_compare(jove_obj_t *a, jove_obj_t *b);
+
 #endif
diff --git a/proc/process.c b/proc/process.c
index 62c0269..f0b83c6 100644
--- a/proc/process.c
+++ b/proc/process.c
@@ -18,7 +18,7 @@ pcb_new(jove_owned_obj_t *pcb_obj, size_t size, jove_owned_obj_t *rootdir_obj)
 
     pcb_header->size = size;
     pcb_header->pid = __next_pid++;
-    pcb_header->rootdir = obj_asunowned(rootdir_obj);
+    pcb_header->rootdir = obj_release(rootdir_obj);
 
     pcb_header->tree_node.get_key = (void*)pcb_getpid;
     pcb_tree = rbtree_insert(pcb_tree, &pcb_header->tree_node);
diff --git a/sys/objdir.c b/sys/objdir.c
index eab935f..f956309 100644
--- a/sys/objdir.c
+++ b/sys/objdir.c
@@ -112,6 +112,13 @@ objdir_trygetobj(
     }
 }
 
+bool
+objdir_compare(jove_owned_obj_t *objdir_obj, objpath_part_t entry, jove_obj_t *obj)
+{
+    jove_obj_t peekobj = objdir_peeklocal(objdir_obj, entry);
+    return obj_compare(&peekobj, obj);
+}
+
 void
 objdir_swapobj(jove_owned_obj_t *a, jove_owned_obj_t *b)
 {
diff --git a/sys/objdir.h b/sys/objdir.h
index e2ae7ef..e86e582 100644
--- a/sys/objdir.h
+++ b/sys/objdir.h
@@ -1,6 +1,7 @@
 #ifndef _JOVE_SYS_OBJDIR_H
 #define _JOVE_SYS_OBJDIR_H 1
 
+#include "api/obj.h"
 #include "hal/obj.h"
 
 int objdir_new(jove_owned_obj_t *untyped_obj);
@@ -23,6 +24,7 @@ jove_owned_obj_t *objdir_getobj(jove_owned_obj_t *objdir_obj, const uint16_t *pa
 /*Same as objdir_getobj but does not block if child objects are locked.*/
 jove_owned_obj_t *objdir_trygetobj(jove_owned_obj_t *objdir_obj, const uint16_t *path, size_t path_len);
 
+bool objdir_compare(jove_owned_obj_t *objdir_obj, objpath_part_t entry, jove_obj_t *obj);
 void objdir_swapobj(jove_owned_obj_t *a, jove_owned_obj_t *b);
 
 #endif
diff --git a/sys/syscall_untyped.c b/sys/syscall_untyped.c
index 1ec21c7..c4378ea 100644
--- a/sys/syscall_untyped.c
+++ b/sys/syscall_untyped.c
@@ -1,8 +1,11 @@
+#include "api/process.h"
 #include "arch/x86_64/hal/obj.h"
 #include "hal/memory.h"
+#include "hal/obj.h"
 #include "jove.h"
 #include "lib/printf.h"
 #include "proc/process.h"
+#include "sys/objdir.h"
 #include "syscall.h"
 
 static int
@@ -91,6 +94,10 @@ s_syscall_untyped_retype_pcb(jove_owned_obj_t *untyped_obj,
         return -errno;
     }
     CHECK_OBJPERM(objdir_obj, JOVE_PERM_ALL, "New PCB needs full access to it's root objdir!");
+    if(!objdir_compare(objdir_obj.obj, PCB_ROOTDIR_SELF_I, obj_asunowned(untyped_obj))) {
+        klogf("Untyped is not in objdir entry %i\n", PCB_ROOTDIR_SELF_I);
+        return -EBADPATH;
+    }
 
     obj_settype(untyped_obj, JOVE_OBJ_PCB);
     return pcb_new(untyped_obj, untyped->limit, objdir_obj.obj);
-- 
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