uml: fix mm_context memory leak

[mv-sheeva.git] / arch / um / kernel / skas / mmu.c

diff --git a/arch/um/kernel/skas/mmu.c b/arch/um/kernel/skas/mmu.c
index 78b3e9f69d57d6a81d9ac446e9f6edc16586e5fe..0cd9a7a05e777bf79447af2338a9f6aaa784281d 100644 (file)
--- a/arch/um/kernel/skas/mmu.c
+++ b/arch/um/kernel/skas/mmu.c
@@ -91,6 +91,8 @@ int init_new_context(struct task_struct *task, struct mm_struct *mm)
                goto out_free;
        }
 
+       to_mm->stub_pages = NULL;
+
        return 0;
 
  out_free:
@@ -126,6 +128,7 @@ void arch_dup_mmap(struct mm_struct *oldmm, struct mm_struct *mm)
 
        pages[0] = virt_to_page(&__syscall_stub_start);
        pages[1] = virt_to_page(mm->context.id.stack);
+       mm->context.stub_pages = pages;
 
        /* dup_mmap already holds mmap_sem */
        err = install_special_mapping(mm, STUB_START, STUB_END - STUB_START,
@@ -147,6 +150,8 @@ void arch_exit_mmap(struct mm_struct *mm)
 {
        pte_t *pte;
 
+       if (mm->context.stub_pages != NULL)
+               kfree(mm->context.stub_pages);
        pte = virt_to_pte(mm, STUB_CODE);
        if (pte != NULL)
                pte_clear(mm, STUB_CODE, pte);