Merge branches 'for-3.15/upstream-fixes' and 'for-3.16/upstream' into for-linus

Conflicts:
	drivers/hid/hid-sensor-hub.c

1 files changed, 51 insertions, 2 deletions

diff --git a/mm/util.c b/mm/util.c
index a24aa22f2473..f380af7ea779 100644
--- a/mm/util.c
+++ b/mm/util.c
@@ -1,6 +1,7 @@
 #include <linux/mm.h>
 #include <linux/slab.h>
 #include <linux/string.h>
+#include <linux/compiler.h>
 #include <linux/export.h>
 #include <linux/err.h>
 #include <linux/sched.h>
@@ -307,7 +308,7 @@ void arch_pick_mmap_layout(struct mm_struct *mm)
  * If the architecture not support this function, simply return with no
  * page pinned
  */
-int __attribute__((weak)) __get_user_pages_fast(unsigned long start,
+int __weak __get_user_pages_fast(unsigned long start,
 				 int nr_pages, int write, struct page **pages)
 {
 	return 0;
@@ -338,7 +339,7 @@ EXPORT_SYMBOL_GPL(__get_user_pages_fast);
  * callers need to carefully consider what to use. On many architectures,
  * get_user_pages_fast simply falls back to get_user_pages.
  */
-int __attribute__((weak)) get_user_pages_fast(unsigned long start,
+int __weak get_user_pages_fast(unsigned long start,
 				int nr_pages, int write, struct page **pages)
 {
 	struct mm_struct *mm = current->mm;
@@ -445,6 +446,54 @@ unsigned long vm_commit_limit(void)
 	return allowed;
 }
 
+/**
+ * get_cmdline() - copy the cmdline value to a buffer.
+ * @task:     the task whose cmdline value to copy.
+ * @buffer:   the buffer to copy to.
+ * @buflen:   the length of the buffer. Larger cmdline values are truncated
+ *            to this length.
+ * Returns the size of the cmdline field copied. Note that the copy does
+ * not guarantee an ending NULL byte.
+ */
+int get_cmdline(struct task_struct *task, char *buffer, int buflen)
+{
+	int res = 0;
+	unsigned int len;
+	struct mm_struct *mm = get_task_mm(task);
+	if (!mm)
+		goto out;
+	if (!mm->arg_end)
+		goto out_mm;	/* Shh! No looking before we're done */
+
+	len = mm->arg_end - mm->arg_start;
+
+	if (len > buflen)
+		len = buflen;
+
+	res = access_process_vm(task, mm->arg_start, buffer, len, 0);
+
+	/*
+	 * If the nul at the end of args has been overwritten, then
+	 * assume application is using setproctitle(3).
+	 */
+	if (res > 0 && buffer[res-1] != '\0' && len < buflen) {
+		len = strnlen(buffer, res);
+		if (len < res) {
+			res = len;
+		} else {
+			len = mm->env_end - mm->env_start;
+			if (len > buflen - res)
+				len = buflen - res;
+			res += access_process_vm(task, mm->env_start,
+						 buffer+res, len, 0);
+			res = strnlen(buffer, res);
+		}
+	}
+out_mm:
+	mmput(mm);
+out:
+	return res;
+}
 
 /* Tracepoints definitions. */
 EXPORT_TRACEPOINT_SYMBOL(kmalloc);