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authorLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 15:20:36 -0700
committerLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 15:20:36 -0700
commit1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch)
tree0bba044c4ce775e45a88a51686b5d9f90697ea9d /arch/frv/kernel/uaccess.c
downloadlinux-1da177e4c3f41524e886b7f1b8a0c1fc7321cac2.tar.gz
Linux-2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!
Diffstat (limited to 'arch/frv/kernel/uaccess.c')
-rw-r--r--arch/frv/kernel/uaccess.c95
1 files changed, 95 insertions, 0 deletions
diff --git a/arch/frv/kernel/uaccess.c b/arch/frv/kernel/uaccess.c
new file mode 100644
index 000000000000..f3fd58a5bc4a
--- /dev/null
+++ b/arch/frv/kernel/uaccess.c
@@ -0,0 +1,95 @@
+/* uaccess.c: userspace access functions
+ *
+ * Copyright (C) 2004 Red Hat, Inc. All Rights Reserved.
+ * Written by David Howells (dhowells@redhat.com)
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ */
+
+#include <linux/mm.h>
+#include <asm/uaccess.h>
+
+/*****************************************************************************/
+/*
+ * copy a null terminated string from userspace
+ */
+long strncpy_from_user(char *dst, const char *src, long count)
+{
+	unsigned long max;
+	char *p, ch;
+	long err = -EFAULT;
+
+	if (count < 0)
+		BUG();
+
+	p = dst;
+
+#ifndef CONFIG_MMU
+	if ((unsigned long) src < memory_start)
+		goto error;
+#endif
+
+	if ((unsigned long) src >= get_addr_limit())
+		goto error;
+
+	max = get_addr_limit() - (unsigned long) src;
+	if ((unsigned long) count > max) {
+		memset(dst + max, 0, count - max);
+		count = max;
+	}
+
+	err = 0;
+	for (; count > 0; count--, p++, src++) {
+		__get_user_asm(err, ch, src, "ub", "=r");
+		if (err < 0)
+			goto error;
+		if (!ch)
+			break;
+		*p = ch;
+	}
+
+	err = p - dst; /* return length excluding NUL */
+
+ error:
+	if (count > 0)
+		memset(p, 0, count); /* clear remainder of buffer [security] */
+
+	return err;
+} /* end strncpy_from_user() */
+
+/*****************************************************************************/
+/*
+ * Return the size of a string (including the ending 0)
+ *
+ * Return 0 on exception, a value greater than N if too long
+ */
+long strnlen_user(const char *src, long count)
+{
+	const char *p;
+	long err = 0;
+	char ch;
+
+	if (count < 0)
+		BUG();
+
+#ifndef CONFIG_MMU
+	if ((unsigned long) src < memory_start)
+		return 0;
+#endif
+
+	if ((unsigned long) src >= get_addr_limit())
+		return 0;
+
+	for (p = src; count > 0; count--, p++) {
+		__get_user_asm(err, ch, p, "ub", "=r");
+		if (err < 0)
+			return 0;
+		if (!ch)
+			break;
+	}
+
+	return p - src + 1; /* return length including NUL */
+} /* end strnlen_user() */