[patch 38/94] [PATCH 07/44] [CVE-2009-0029] System call wrapperinfrastructure

From: Greg KH
Date: Thu Jan 15 2009 - 15:25:23 EST


2.6.28-stable review patch. If anyone has any objections, please let us know.

------------------

From: Heiko Carstens <heiko.carstens@xxxxxxxxxx>

commit 1a94bc34768e463a93cb3751819709ab0ea80a01 upstream.

From: Martin Schwidefsky <schwidefsky@xxxxxxxxxx>

By selecting HAVE_SYSCALL_WRAPPERS architectures can activate
system call wrappers in order to sign extend system call arguments.

All architectures where the ABI defines that the caller of a function
has to perform sign extension probably need this.

Reported-by: Christian Borntraeger <borntraeger@xxxxxxxxxx>
Acked-by: Ralf Baechle <ralf@xxxxxxxxxxxxxx>
Signed-off-by: Martin Schwidefsky <schwidefsky@xxxxxxxxxx>
Signed-off-by: Heiko Carstens <heiko.carstens@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxx>
---
arch/Kconfig | 3 ++
include/linux/syscalls.h | 62 +++++++++++++++++++++++++++++++++++++++++++++++
2 files changed, 65 insertions(+)

--- a/arch/Kconfig
+++ b/arch/Kconfig
@@ -60,6 +60,9 @@ config HAVE_EFFICIENT_UNALIGNED_ACCESS
See Documentation/unaligned-memory-access.txt for more
information on the topic of unaligned memory accesses.

+config HAVE_SYSCALL_WRAPPERS
+ bool
+
config KRETPROBES
def_bool y
depends on KPROBES && HAVE_KRETPROBES
--- a/include/linux/syscalls.h
+++ b/include/linux/syscalls.h
@@ -66,6 +66,68 @@ struct old_linux_dirent;
#include <linux/quota.h>
#include <linux/key.h>

+#define __SC_DECL1(t1, a1) t1 a1
+#define __SC_DECL2(t2, a2, ...) t2 a2, __SC_DECL1(__VA_ARGS__)
+#define __SC_DECL3(t3, a3, ...) t3 a3, __SC_DECL2(__VA_ARGS__)
+#define __SC_DECL4(t4, a4, ...) t4 a4, __SC_DECL3(__VA_ARGS__)
+#define __SC_DECL5(t5, a5, ...) t5 a5, __SC_DECL4(__VA_ARGS__)
+#define __SC_DECL6(t6, a6, ...) t6 a6, __SC_DECL5(__VA_ARGS__)
+
+#define __SC_LONG1(t1, a1) long a1
+#define __SC_LONG2(t2, a2, ...) long a2, __SC_LONG1(__VA_ARGS__)
+#define __SC_LONG3(t3, a3, ...) long a3, __SC_LONG2(__VA_ARGS__)
+#define __SC_LONG4(t4, a4, ...) long a4, __SC_LONG3(__VA_ARGS__)
+#define __SC_LONG5(t5, a5, ...) long a5, __SC_LONG4(__VA_ARGS__)
+#define __SC_LONG6(t6, a6, ...) long a6, __SC_LONG5(__VA_ARGS__)
+
+#define __SC_CAST1(t1, a1) (t1) a1
+#define __SC_CAST2(t2, a2, ...) (t2) a2, __SC_CAST1(__VA_ARGS__)
+#define __SC_CAST3(t3, a3, ...) (t3) a3, __SC_CAST2(__VA_ARGS__)
+#define __SC_CAST4(t4, a4, ...) (t4) a4, __SC_CAST3(__VA_ARGS__)
+#define __SC_CAST5(t5, a5, ...) (t5) a5, __SC_CAST4(__VA_ARGS__)
+#define __SC_CAST6(t6, a6, ...) (t6) a6, __SC_CAST5(__VA_ARGS__)
+
+#define __SC_TEST(type) BUILD_BUG_ON(sizeof(type) > sizeof(long))
+#define __SC_TEST1(t1, a1) __SC_TEST(t1)
+#define __SC_TEST2(t2, a2, ...) __SC_TEST(t2); __SC_TEST1(__VA_ARGS__)
+#define __SC_TEST3(t3, a3, ...) __SC_TEST(t3); __SC_TEST2(__VA_ARGS__)
+#define __SC_TEST4(t4, a4, ...) __SC_TEST(t4); __SC_TEST3(__VA_ARGS__)
+#define __SC_TEST5(t5, a5, ...) __SC_TEST(t5); __SC_TEST4(__VA_ARGS__)
+#define __SC_TEST6(t6, a6, ...) __SC_TEST(t6); __SC_TEST5(__VA_ARGS__)
+
+#define SYSCALL_DEFINE0(name) asmlinkage long sys_##name(void)
+#define SYSCALL_DEFINE1(...) SYSCALL_DEFINEx(1, __VA_ARGS__)
+#define SYSCALL_DEFINE2(...) SYSCALL_DEFINEx(2, __VA_ARGS__)
+#define SYSCALL_DEFINE3(...) SYSCALL_DEFINEx(3, __VA_ARGS__)
+#define SYSCALL_DEFINE4(...) SYSCALL_DEFINEx(4, __VA_ARGS__)
+#define SYSCALL_DEFINE5(...) SYSCALL_DEFINEx(5, __VA_ARGS__)
+#define SYSCALL_DEFINE6(...) SYSCALL_DEFINEx(6, __VA_ARGS__)
+
+#define SYSCALL_ALIAS(alias, name) \
+ asm ("\t.globl " #alias "\n\t.set " #alias ", " #name)
+
+#ifdef CONFIG_HAVE_SYSCALL_WRAPPERS
+
+#define SYSCALL_DEFINE(name) static inline long SYSC_##name
+#define SYSCALL_DEFINEx(x, name, ...) \
+ asmlinkage long sys_##name(__SC_DECL##x(__VA_ARGS__)); \
+ static inline long SYSC_##name(__SC_DECL##x(__VA_ARGS__)); \
+ asmlinkage long SyS_##name(__SC_LONG##x(__VA_ARGS__)) \
+ { \
+ __SC_TEST##x(__VA_ARGS__); \
+ return (long) SYSC_##name(__SC_CAST##x(__VA_ARGS__)); \
+ } \
+ SYSCALL_ALIAS(sys_##name, SyS_##name); \
+ static inline long SYSC_##name(__SC_DECL##x(__VA_ARGS__))
+
+#else /* CONFIG_HAVE_SYSCALL_WRAPPERS */
+
+#define SYSCALL_DEFINE(name) asmlinkage long sys_##name
+#define SYSCALL_DEFINEx(x, name, ...) \
+ asmlinkage long sys_##name(__SC_DECL##x(__VA_ARGS__))
+
+#endif /* CONFIG_HAVE_SYSCALL_WRAPPERS */
+
asmlinkage long sys_time(time_t __user *tloc);
asmlinkage long sys_stime(time_t __user *tptr);
asmlinkage long sys_gettimeofday(struct timeval __user *tv,

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