sys rcu fix

Signed-off-by: Liam R. Howlett <Liam.Howlett@Oracle.com>

diff --git a/kernel/sys.c b/kernel/sys.c
index 7f6204c2c86e68b5752b1718f2b43a518a33e175..1f1835c177b1d45d1a23729e3852b6c783743195 100644 (file)
--- a/kernel/sys.c
+++ b/kernel/sys.c
@@ -1862,6 +1862,7 @@ static int prctl_set_mm_exe_file(struct mm_struct *mm, unsigned int fd)
                MA_STATE(mas, &mm->mm_mt, 0, 0);
 
                mmap_read_lock(mm);
+               rcu_read_lock();
                mas_for_each(&mas, vma, ULONG_MAX) {
                        if (!vma->vm_file)
                                continue;
@@ -1870,6 +1871,7 @@ static int prctl_set_mm_exe_file(struct mm_struct *mm, unsigned int fd)
                                goto exit_err;
                }
 
+               rcu_read_unlock();
                mmap_read_unlock(mm);
                fput(exe_file);
        }
@@ -1884,6 +1886,7 @@ exit:
        fdput(exe);
        return err;
 exit_err:
+       rcu_read_unlock();
        mmap_read_unlock(mm);
        fput(exe_file);
        goto exit;