1 files changed, 11 insertions, 12 deletions

diff --git a/fs/proc/task_mmu.c b/fs/proc/task_mmu.c
index 636f1a1fdf87..7c708a418acc 100644
--- a/fs/proc/task_mmu.c
+++ b/fs/proc/task_mmu.c
@@ -121,14 +121,14 @@ static void *m_start(struct seq_file *m, loff_t *pos)
 
         priv->task = get_pid_task(priv->pid, PIDTYPE_PID);
         if (!priv->task)
-                return NULL;
+                return ERR_PTR(-ESRCH);
 
         mm = mm_for_maps(priv->task);
-        if (!mm)
-                return NULL;
+        if (!mm || IS_ERR(mm))
+                return mm;
         down_read(&mm->mmap_sem);
 
-        tail_vma = get_gate_vma(priv->task);
+        tail_vma = get_gate_vma(priv->task->mm);
         priv->tail_vma = tail_vma;
 
         /* Start with last addr hint */
@@ -279,7 +279,8 @@ static int show_map(struct seq_file *m, void *v)
         show_map_vma(m, vma);
 
         if (m->count < m->size)  /* vma is copied successfully */
-                m->version = (vma != get_gate_vma(task))? vma->vm_start: 0;
+                m->version = (vma != get_gate_vma(task->mm))
+                        ? vma->vm_start : 0;
         return 0;
 }
 
@@ -468,7 +469,8 @@ static int show_smap(struct seq_file *m, void *v)
                         (unsigned long)(mss.pss >> (10 + PSS_SHIFT)) : 0);
 
         if (m->count < m->size)  /* vma is copied successfully */
-                m->version = (vma != get_gate_vma(task)) ? vma->vm_start : 0;
+                m->version = (vma != get_gate_vma(task->mm))
+                        ? vma->vm_start : 0;
         return 0;
 }
 
@@ -764,8 +766,9 @@ static ssize_t pagemap_read(struct file *file, char __user *buf,
         if (!task)
                 goto out;
 
-        ret = -EACCES;
-        if (!ptrace_may_access(task, PTRACE_MODE_READ))
+        mm = mm_for_maps(task);
+        ret = PTR_ERR(mm);
+        if (!mm || IS_ERR(mm))
                 goto out_task;
 
         ret = -EINVAL;
@@ -778,10 +781,6 @@ static ssize_t pagemap_read(struct file *file, char __user *buf,
         if (!count)
                 goto out_task;
 
-        mm = get_task_mm(task);
-        if (!mm)
-                goto out_task;
-
         pm.len = PM_ENTRY_BYTES * (PAGEMAP_WALK_SIZE >> PAGE_SHIFT);
         pm.buffer = kmalloc(pm.len, GFP_TEMPORARY);
         ret = -ENOMEM;