1 files changed, 12 insertions, 0 deletions

diff --git a/ipc/shm.c b/ipc/shm.c
index b125b560240e..d0ab5527bf45 100644
--- a/ipc/shm.c
+++ b/ipc/shm.c
@@ -990,6 +990,7 @@ asmlinkage long sys_shmdt(char __user *shmaddr)
          */
         vma = find_vma(mm, addr);
 
+#ifdef CONFIG_MMU
         while (vma) {
                 next = vma->vm_next;
 
@@ -1034,6 +1035,17 @@ asmlinkage long sys_shmdt(char __user *shmaddr)
                 vma = next;
         }
 
+#else /* CONFIG_MMU */
+        /* under NOMMU conditions, the exact address to be destroyed must be
+         * given */
+        retval = -EINVAL;
+        if (vma->vm_start == addr && vma->vm_ops == &shm_vm_ops) {
+                do_munmap(mm, vma->vm_start, vma->vm_end - vma->vm_start);
+                retval = 0;
+        }
+
+#endif
+
         up_write(&mm->mmap_sem);
         return retval;
 }