diff --git a/kernel/syscall/ipcpipe.c b/kernel/syscall/ipcpipe.c
index 53ff338..e2c4ba3 100644
--- a/kernel/syscall/ipcpipe.c
+++ b/kernel/syscall/ipcpipe.c
@@ -68,11 +68,11 @@ int32_t SYSCALL5(sys_ipcpipe, pid1, pipenum1, cmd1, buffer1, len1) {
       }
 
       spinlock_acquire(&proc->pipes_spinlock);
-      if (proc->pipes[pipenum] != NULL) {
+      if (proc->pipes[pipenum] != NULL && proc->pid == proc->pipes[pipenum]->ownerpid) {
         ipc_pipefree(proc->pipes[pipenum]);
         dlfree(proc->pipes[pipenum]);
-        proc->pipes[pipenum] = NULL;
       }
+      proc->pipes[pipenum] = NULL;
       spinlock_release(&proc->pipes_spinlock);
       ret = E_OK;
     } break;
@@ -182,10 +182,9 @@ int32_t SYSCALL5(sys_ipcpipe, pid1, pipenum1, cmd1, buffer1, len1) {
       spinlock_acquire(&proc2->pipes_spinlock);
       spinlock_acquire(&proc->pipes_spinlock);
 
-      if (proc->pipes[pipenum] != NULL) {
+      if (proc->pipes[pipenum] != NULL && proc->pid == proc->pipes[pipenum]->ownerpid) {
         ipc_pipefree(proc->pipes[pipenum]);
         dlfree(proc->pipes[pipenum]);
-        proc->pipes[pipenum] = NULL;
       }
       proc->pipes[pipenum] = proc2->pipes[pipenum2];
 
diff --git a/kernel/syscall/processctl.c b/kernel/syscall/processctl.c
index b694a16..81b5db3 100644
--- a/kernel/syscall/processctl.c
+++ b/kernel/syscall/processctl.c
@@ -62,10 +62,10 @@ int32_t SYSCALL5(sys_processctl, pid1, cmd1, arg1, arg2, arg3) {
       }
 
       size_t argslen = arg3;
-      char *(*args)[] = (char *(*)[])arg2;
+      char **args = (char **)arg2;
       if (args != NULL && argslen > 0) {
         for (size_t i = 0; i < argslen; i++) {
-          PROC_ARG(newproc, (*args)[i]);
+          PROC_ARG(newproc, args[i]);
         }
       }