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authorAnton Arapov <anton@redhat.com>2012-04-16 10:05:28 +0200
committerAnton Arapov <anton@redhat.com>2012-04-16 10:05:28 +0200
commitb4b6116a13633898cf868f2f103c96a90c4c20f8 (patch)
tree93d1b7e2cfcdf473d8d4ff3ad141fa864f8491f6 /arch/arm/lib/strncpy_from_user.S
parentedd4be777c953e5faafc80d091d3084b4343f5d3 (diff)
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fedora kernel: d9aad82f3319f3cfd1aebc01234254ef0c37ad84v3.3.2-1
Signed-off-by: Anton Arapov <anton@redhat.com>
Diffstat (limited to 'arch/arm/lib/strncpy_from_user.S')
-rw-r--r--arch/arm/lib/strncpy_from_user.S43
1 files changed, 43 insertions, 0 deletions
diff --git a/arch/arm/lib/strncpy_from_user.S b/arch/arm/lib/strncpy_from_user.S
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+++ b/arch/arm/lib/strncpy_from_user.S
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+/*
+ * linux/arch/arm/lib/strncpy_from_user.S
+ *
+ * Copyright (C) 1995-2000 Russell King
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+#include <linux/linkage.h>
+#include <asm/assembler.h>
+#include <asm/errno.h>
+
+ .text
+ .align 5
+
+/*
+ * Copy a string from user space to kernel space.
+ * r0 = dst, r1 = src, r2 = byte length
+ * returns the number of characters copied (strlen of copied string),
+ * -EFAULT on exception, or "len" if we fill the whole buffer
+ */
+ENTRY(__strncpy_from_user)
+ mov ip, r1
+1: subs r2, r2, #1
+ ldrusr r3, r1, 1, pl
+ bmi 2f
+ strb r3, [r0], #1
+ teq r3, #0
+ bne 1b
+ sub r1, r1, #1 @ take NUL character out of count
+2: sub r0, r1, ip
+ mov pc, lr
+ENDPROC(__strncpy_from_user)
+
+ .pushsection .fixup,"ax"
+ .align 0
+9001: mov r3, #0
+ strb r3, [r0, #0] @ null terminate
+ mov r0, #-EFAULT
+ mov pc, lr
+ .popsection
+