1 files changed, 4 insertions, 0 deletions

diff --git a/fs/proc/task_mmu.c b/fs/proc/task_mmu.c
index 39e4ad4f59f..6f61b7cc32e 100644
--- a/fs/proc/task_mmu.c
+++ b/fs/proc/task_mmu.c
@@ -665,6 +665,10 @@ static ssize_t pagemap_read(struct file *file, char __user *buf,
                 goto out_task;
 
         ret = 0;
+
+        if (!count)
+                goto out_task;
+
         mm = get_task_mm(task);
         if (!mm)
                 goto out_task;