Merge branch 'linux-linaro-lsk-v4.4' into linux-linaro-lsk-v4.4-android

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

diff --git a/fs/proc/base.c b/fs/proc/base.c
index 57df8a52e780c90d1fa433cf00146d03e174f09d..23d60b1995fb29e89cf37c93464ca0274cb8cf59 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);