1 files changed, 72 insertions, 27 deletions

diff --git a/fs/proc/base.c b/fs/proc/base.c
index dc5d5f51f3fe..53dc8ad40ae6 100644
--- a/fs/proc/base.c
+++ b/fs/proc/base.c
@@ -1023,28 +1023,47 @@ static ssize_t oom_adjust_write(struct file *file, const char __user *buf,
         memset(buffer, 0, sizeof(buffer));
         if (count > sizeof(buffer) - 1)
                 count = sizeof(buffer) - 1;
-        if (copy_from_user(buffer, buf, count))
-                return -EFAULT;
+        if (copy_from_user(buffer, buf, count)) {
+                err = -EFAULT;
+                goto out;
+        }
 
         err = strict_strtol(strstrip(buffer), 0, &oom_adjust);
         if (err)
-                return -EINVAL;
+                goto out;
         if ((oom_adjust < OOM_ADJUST_MIN || oom_adjust > OOM_ADJUST_MAX) &&
-             oom_adjust != OOM_DISABLE)
-                return -EINVAL;
+             oom_adjust != OOM_DISABLE) {
+                err = -EINVAL;
+                goto out;
+        }
 
         task = get_proc_task(file->f_path.dentry->d_inode);
-        if (!task)
-                return -ESRCH;
+        if (!task) {
+                err = -ESRCH;
+                goto out;
+        }
+
+        task_lock(task);
+        if (!task->mm) {
+                err = -EINVAL;
+                goto err_task_lock;
+        }
+
         if (!lock_task_sighand(task, &flags)) {
-                put_task_struct(task);
-                return -ESRCH;
+                err = -ESRCH;
+                goto err_task_lock;
         }
 
         if (oom_adjust < task->signal->oom_adj && !capable(CAP_SYS_RESOURCE)) {
-                unlock_task_sighand(task, &flags);
-                put_task_struct(task);
-                return -EACCES;
+                err = -EACCES;
+                goto err_sighand;
+        }
+
+        if (oom_adjust != task->signal->oom_adj) {
+                if (oom_adjust == OOM_DISABLE)
+                        atomic_inc(&task->mm->oom_disable_count);
+                if (task->signal->oom_adj == OOM_DISABLE)
+                        atomic_dec(&task->mm->oom_disable_count);
         }
 
         /*
@@ -1065,10 +1084,13 @@ static ssize_t oom_adjust_write(struct file *file, const char __user *buf,
         else
                 task->signal->oom_score_adj = (oom_adjust * OOM_SCORE_ADJ_MAX) /
                                                                 -OOM_DISABLE;
+err_sighand:
         unlock_task_sighand(task, &flags);
+err_task_lock:
+        task_unlock(task);
         put_task_struct(task);
-
-        return count;
+out:
+        return err < 0 ? err : count;
 }
 
 static const struct file_operations proc_oom_adjust_operations = {
@@ -1109,30 +1131,49 @@ static ssize_t oom_score_adj_write(struct file *file, const char __user *buf,
         memset(buffer, 0, sizeof(buffer));
         if (count > sizeof(buffer) - 1)
                 count = sizeof(buffer) - 1;
-        if (copy_from_user(buffer, buf, count))
-                return -EFAULT;
+        if (copy_from_user(buffer, buf, count)) {
+                err = -EFAULT;
+                goto out;
+        }
 
         err = strict_strtol(strstrip(buffer), 0, &oom_score_adj);
         if (err)
-                return -EINVAL;
+                goto out;
         if (oom_score_adj < OOM_SCORE_ADJ_MIN ||
-                        oom_score_adj > OOM_SCORE_ADJ_MAX)
-                return -EINVAL;
+                        oom_score_adj > OOM_SCORE_ADJ_MAX) {
+                err = -EINVAL;
+                goto out;
+        }
 
         task = get_proc_task(file->f_path.dentry->d_inode);
-        if (!task)
-                return -ESRCH;
+        if (!task) {
+                err = -ESRCH;
+                goto out;
+        }
+
+        task_lock(task);
+        if (!task->mm) {
+                err = -EINVAL;
+                goto err_task_lock;
+        }
+
         if (!lock_task_sighand(task, &flags)) {
-                put_task_struct(task);
-                return -ESRCH;
+                err = -ESRCH;
+                goto err_task_lock;
         }
+
         if (oom_score_adj < task->signal->oom_score_adj &&
                         !capable(CAP_SYS_RESOURCE)) {
-                unlock_task_sighand(task, &flags);
-                put_task_struct(task);
-                return -EACCES;
+                err = -EACCES;
+                goto err_sighand;
         }
 
+        if (oom_score_adj != task->signal->oom_score_adj) {
+                if (oom_score_adj == OOM_SCORE_ADJ_MIN)
+                        atomic_inc(&task->mm->oom_disable_count);
+                if (task->signal->oom_score_adj == OOM_SCORE_ADJ_MIN)
+                        atomic_dec(&task->mm->oom_disable_count);
+        }
         task->signal->oom_score_adj = oom_score_adj;
         /*
          * Scale /proc/pid/oom_adj appropriately ensuring that OOM_DISABLE is
@@ -1143,9 +1184,13 @@ static ssize_t oom_score_adj_write(struct file *file, const char __user *buf,
         else
                 task->signal->oom_adj = (oom_score_adj * OOM_ADJUST_MAX) /
                                                         OOM_SCORE_ADJ_MAX;
+err_sighand:
         unlock_task_sighand(task, &flags);
+err_task_lock:
+        task_unlock(task);
         put_task_struct(task);
-        return count;
+out:
+        return err < 0 ? err : count;
 }
 
 static const struct file_operations proc_oom_score_adj_operations = {