1 files changed, 7 insertions, 1 deletions

diff --git a/fs/proc/base.c b/fs/proc/base.c
index fb45615943c2..1539e630c47d 100644
--- a/fs/proc/base.c
+++ b/fs/proc/base.c
@@ -1956,7 +1956,7 @@ static struct dentry *proc_pident_instantiate(struct inode *dir,
         const struct pid_entry *p = ptr;
         struct inode *inode;
         struct proc_inode *ei;
-        struct dentry *error = ERR_PTR(-EINVAL);
+        struct dentry *error = ERR_PTR(-ENOENT);
 
         inode = proc_pid_make_inode(dir->i_sb, task);
         if (!inode)
@@ -2128,9 +2128,15 @@ static ssize_t proc_pid_attr_write(struct file * file, const char __user * buf,
         if (copy_from_user(page, buf, count))
                 goto out_free;
 
+        /* Guard against adverse ptrace interaction */
+        length = mutex_lock_interruptible(&task->cred_guard_mutex);
+        if (length < 0)
+                goto out_free;
+
         length = security_setprocattr(task,
                                       (char*)file->f_path.dentry->d_name.name,
                                       (void*)page, count);
+        mutex_unlock(&task->cred_guard_mutex);
 out_free:
         free_page((unsigned long) page);
 out: