net: sched: do not requeue a NULL skb

[firefly-linux-kernel-4.4.55.git] / fs / proc / base.c

diff --git a/fs/proc/base.c b/fs/proc/base.c
index b7de324bec1193dbb0d0eed756bcfbbb82e898ba..e8bbf6cdb43782aea48022d0cd6f8fb8f9afd337 100644 (file)
--- a/fs/proc/base.c
+++ b/fs/proc/base.c
@@ -954,7 +954,8 @@ static ssize_t environ_read(struct file *file, char __user *buf,
        int ret = 0;
        struct mm_struct *mm = file->private_data;
 
-       if (!mm)
+       /* Ensure the process spawned far enough to have an environment. */
+       if (!mm || !mm->env_end)
                return 0;
 
        page = (char *)__get_free_page(GFP_TEMPORARY);