The patch titled
Expose range-checking functions from arch-specific uaccess.h
has been added to the -mm tree. Its filename is
expose-range-checking-functions-from-arch-specific.patch
*** Remember to use Documentation/SubmitChecklist when testing your code ***
See http://www.zip.com.au/~akpm/linux/patches/stuff/added-to-mm.txt to find
out what to do about this
------------------------------------------------------
Subject: Expose range-checking functions from arch-specific uaccess.h
From: Rusty Russell <rusty@xxxxxxxxxxxxxxx>
There are some places where we want to check if a value + length is within
a range. This can be tricky, so it's nice to have a single routine.
Also, this can be done more efficiently (with arch-dependent) carry bits,
as shown by the __range_ok() implementation on several archs.
This patch exposes arch-specific "val_outside(val, len, limit)" and a
generic "range_within(start, len, base, limit)" function. As a
side-effect, it fixes the comment in i386/uaccess.h: __range_ok doesn't
test "(u33)addr + (u33)size >= (u33)current->addr_limit.seg", it tests
"(u33)addr + (u33)size > (u33)current->addr_limit.seg".
Signed-off-by: Rusty Russell <rusty@xxxxxxxxxxxxxxx>
Cc: <linux-arch@xxxxxxxxxxxxxxx>
Cc: Randy Dunlap <randy.dunlap@xxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
include/asm-alpha/range.h | 6 ++++++
include/asm-arm/range.h | 6 ++++++
include/asm-arm26/range.h | 6 ++++++
include/asm-avr32/range.h | 6 ++++++
include/asm-blackfin/range.h | 6 ++++++
include/asm-cris/range.h | 6 ++++++
include/asm-frv/range.h | 6 ++++++
include/asm-generic/range.h | 20 ++++++++++++++++++++
include/asm-h8300/range.h | 6 ++++++
include/asm-i386/range.h | 14 ++++++++++++++
include/asm-i386/uaccess.h | 16 ++++++----------
include/asm-ia64/range.h | 6 ++++++
include/asm-m32r/range.h | 6 ++++++
include/asm-m68k/range.h | 6 ++++++
include/asm-m68knommu/range.h | 6 ++++++
include/asm-mips/range.h | 6 ++++++
include/asm-parisc/range.h | 6 ++++++
include/asm-powerpc/range.h | 6 ++++++
include/asm-ppc/range.h | 6 ++++++
include/asm-s390/range.h | 6 ++++++
include/asm-sh/range.h | 6 ++++++
include/asm-sh64/range.h | 6 ++++++
include/asm-sparc/range.h | 6 ++++++
include/asm-sparc64/range.h | 6 ++++++
include/asm-um/range.h | 6 ++++++
include/asm-v850/range.h | 6 ++++++
include/asm-x86_64/range.h | 6 ++++++
include/asm-xtensa/range.h | 6 ++++++
include/linux/kernel.h | 21 +++++++++++++++++++++
29 files changed, 211 insertions(+), 10 deletions(-)
diff -puN /dev/null include/asm-alpha/range.h
--- /dev/null
+++ a/include/asm-alpha/range.h
@@ -0,0 +1,6 @@
+#ifndef __ASM_RANGE_H
+#define __ASM_RANGE_H
+
+#include <asm-generic/range.h>
+
+#endif /* __ASM_RANGE_H */
diff -puN /dev/null include/asm-arm/range.h
--- /dev/null
+++ a/include/asm-arm/range.h
@@ -0,0 +1,6 @@
+#ifndef __ASM_RANGE_H
+#define __ASM_RANGE_H
+
+#include <asm-generic/range.h>
+
+#endif /* __ASM_RANGE_H */
diff -puN /dev/null include/asm-arm26/range.h
--- /dev/null
+++ a/include/asm-arm26/range.h
@@ -0,0 +1,6 @@
+#ifndef __ASM_RANGE_H
+#define __ASM_RANGE_H
+
+#include <asm-generic/range.h>
+
+#endif /* __ASM_RANGE_H */
diff -puN /dev/null include/asm-avr32/range.h
--- /dev/null
+++ a/include/asm-avr32/range.h
@@ -0,0 +1,6 @@
+#ifndef __ASM_RANGE_H
+#define __ASM_RANGE_H
+
+#include <asm-generic/range.h>
+
+#endif /* __ASM_RANGE_H */
diff -puN /dev/null include/asm-blackfin/range.h
--- /dev/null
+++ a/include/asm-blackfin/range.h
@@ -0,0 +1,6 @@
+#ifndef __ASM_RANGE_H
+#define __ASM_RANGE_H
+
+#include <asm-generic/range.h>
+
+#endif /* __ASM_RANGE_H */
diff -puN /dev/null include/asm-cris/range.h
--- /dev/null
+++ a/include/asm-cris/range.h
@@ -0,0 +1,6 @@
+#ifndef __ASM_RANGE_H
+#define __ASM_RANGE_H
+
+#include <asm-generic/range.h>
+
+#endif /* __ASM_RANGE_H */
diff -puN /dev/null include/asm-frv/range.h
--- /dev/null
+++ a/include/asm-frv/range.h
@@ -0,0 +1,6 @@
+#ifndef __ASM_RANGE_H
+#define __ASM_RANGE_H
+
+#include <asm-generic/range.h>
+
+#endif /* __ASM_RANGE_H */
diff -puN /dev/null include/asm-generic/range.h
--- /dev/null
+++ a/include/asm-generic/range.h
@@ -0,0 +1,20 @@
+#ifndef _ASM_GENERIC_RANGE_H
+#define _ASM_GENERIC_RANGE_H
+
+/**
+ * val_outside - is a value and length past a limit?
+ * @val: the start value
+ * @len: the length from the start
+ * @limit: the first invalid value
+ *
+ * Like val + len > limit, except with overflow checking.
+ */
+static inline bool val_outside(unsigned long val, unsigned long len,
+ unsigned long limit)
+
+{
+ return val + len > limit || val + len < val;
+}
+
+#endif /* _ASM_GENERIC_RANGE_H */
+
diff -puN /dev/null include/asm-h8300/range.h
--- /dev/null
+++ a/include/asm-h8300/range.h
@@ -0,0 +1,6 @@
+#ifndef __ASM_RANGE_H
+#define __ASM_RANGE_H
+
+#include <asm-generic/range.h>
+
+#endif /* __ASM_RANGE_H */
diff -puN /dev/null include/asm-i386/range.h
--- /dev/null
+++ a/include/asm-i386/range.h
@@ -0,0 +1,14 @@
+#ifndef __ASM_RANGE_H
+#define __ASM_RANGE_H
+
+/* Is val + size > limit? This needs 33-bit arithmetic. We have a carry... */
+static inline bool val_outside(unsigned long val, unsigned long len,
+ unsigned long limit)
+{
+ unsigned long flag, roksum;
+ asm("addl %3,%1 ; sbbl %0,%0; cmpl %1,%4; sbbl $0,%0"
+ :"=&r" (flag), "=r" (roksum)
+ :"1" (val), "g" (len), "rm" (limit));
+ return flag;
+}
+#endif /* __ASM_RANGE_H */
diff -puN include/asm-i386/uaccess.h~expose-range-checking-functions-from-arch-specific include/asm-i386/uaccess.h
--- a/include/asm-i386/uaccess.h~expose-range-checking-functions-from-arch-specific
+++ a/include/asm-i386/uaccess.h
@@ -49,17 +49,13 @@ extern struct movsl_mask {
* Returns 0 if the range is valid, nonzero otherwise.
*
* This is equivalent to the following test:
- * (u33)addr + (u33)size >= (u33)current->addr_limit.seg
- *
- * This needs 33-bit arithmetic. We have a carry...
+ * (u33)addr + (u33)size > (u33)current->addr_limit.seg
*/
-#define __range_ok(addr,size) ({ \
- unsigned long flag,roksum; \
- __chk_user_ptr(addr); \
- asm("addl %3,%1 ; sbbl %0,%0; cmpl %1,%4; sbbl $0,%0" \
- :"=&r" (flag), "=r" (roksum) \
- :"1" (addr),"g" ((int)(size)),"rm" (current_thread_info()->addr_limit.seg)); \
- flag; })
+#define __range_ok(addr, size) ({ \
+ __chk_user_ptr(addr); \
+ val_outside((int)(addr), (size), \
+ current_thread_info()->addr_limit.seg); \
+})
/**
* access_ok: - Checks if a user space pointer is valid
diff -puN /dev/null include/asm-ia64/range.h
--- /dev/null
+++ a/include/asm-ia64/range.h
@@ -0,0 +1,6 @@
+#ifndef __ASM_RANGE_H
+#define __ASM_RANGE_H
+
+#include <asm-generic/range.h>
+
+#endif /* __ASM_RANGE_H */
diff -puN /dev/null include/asm-m32r/range.h
--- /dev/null
+++ a/include/asm-m32r/range.h
@@ -0,0 +1,6 @@
+#ifndef __ASM_RANGE_H
+#define __ASM_RANGE_H
+
+#include <asm-generic/range.h>
+
+#endif /* __ASM_RANGE_H */
diff -puN /dev/null include/asm-m68k/range.h
--- /dev/null
+++ a/include/asm-m68k/range.h
@@ -0,0 +1,6 @@
+#ifndef __ASM_RANGE_H
+#define __ASM_RANGE_H
+
+#include <asm-generic/range.h>
+
+#endif /* __ASM_RANGE_H */
diff -puN /dev/null include/asm-m68knommu/range.h
--- /dev/null
+++ a/include/asm-m68knommu/range.h
@@ -0,0 +1,6 @@
+#ifndef __ASM_RANGE_H
+#define __ASM_RANGE_H
+
+#include <asm-generic/range.h>
+
+#endif /* __ASM_RANGE_H */
diff -puN /dev/null include/asm-mips/range.h
--- /dev/null
+++ a/include/asm-mips/range.h
@@ -0,0 +1,6 @@
+#ifndef __ASM_RANGE_H
+#define __ASM_RANGE_H
+
+#include <asm-generic/range.h>
+
+#endif /* __ASM_RANGE_H */
diff -puN /dev/null include/asm-parisc/range.h
--- /dev/null
+++ a/include/asm-parisc/range.h
@@ -0,0 +1,6 @@
+#ifndef __ASM_RANGE_H
+#define __ASM_RANGE_H
+
+#include <asm-generic/range.h>
+
+#endif /* __ASM_RANGE_H */
diff -puN /dev/null include/asm-powerpc/range.h
--- /dev/null
+++ a/include/asm-powerpc/range.h
@@ -0,0 +1,6 @@
+#ifndef __ASM_RANGE_H
+#define __ASM_RANGE_H
+
+#include <asm-generic/range.h>
+
+#endif /* __ASM_RANGE_H */
diff -puN /dev/null include/asm-ppc/range.h
--- /dev/null
+++ a/include/asm-ppc/range.h
@@ -0,0 +1,6 @@
+#ifndef __ASM_RANGE_H
+#define __ASM_RANGE_H
+
+#include <asm-generic/range.h>
+
+#endif /* __ASM_RANGE_H */
diff -puN /dev/null include/asm-s390/range.h
--- /dev/null
+++ a/include/asm-s390/range.h
@@ -0,0 +1,6 @@
+#ifndef __ASM_RANGE_H
+#define __ASM_RANGE_H
+
+#include <asm-generic/range.h>
+
+#endif /* __ASM_RANGE_H */
diff -puN /dev/null include/asm-sh/range.h
--- /dev/null
+++ a/include/asm-sh/range.h
@@ -0,0 +1,6 @@
+#ifndef __ASM_RANGE_H
+#define __ASM_RANGE_H
+
+#include <asm-generic/range.h>
+
+#endif /* __ASM_RANGE_H */
diff -puN /dev/null include/asm-sh64/range.h
--- /dev/null
+++ a/include/asm-sh64/range.h
@@ -0,0 +1,6 @@
+#ifndef __ASM_RANGE_H
+#define __ASM_RANGE_H
+
+#include <asm-generic/range.h>
+
+#endif /* __ASM_RANGE_H */
diff -puN /dev/null include/asm-sparc/range.h
--- /dev/null
+++ a/include/asm-sparc/range.h
@@ -0,0 +1,6 @@
+#ifndef __ASM_RANGE_H
+#define __ASM_RANGE_H
+
+#include <asm-generic/range.h>
+
+#endif /* __ASM_RANGE_H */
diff -puN /dev/null include/asm-sparc64/range.h
--- /dev/null
+++ a/include/asm-sparc64/range.h
@@ -0,0 +1,6 @@
+#ifndef __ASM_RANGE_H
+#define __ASM_RANGE_H
+
+#include <asm-generic/range.h>
+
+#endif /* __ASM_RANGE_H */
diff -puN /dev/null include/asm-um/range.h
--- /dev/null
+++ a/include/asm-um/range.h
@@ -0,0 +1,6 @@
+#ifndef __ASM_RANGE_H
+#define __ASM_RANGE_H
+
+#include <asm-generic/range.h>
+
+#endif /* __ASM_RANGE_H */
diff -puN /dev/null include/asm-v850/range.h
--- /dev/null
+++ a/include/asm-v850/range.h
@@ -0,0 +1,6 @@
+#ifndef __ASM_RANGE_H
+#define __ASM_RANGE_H
+
+#include <asm-generic/range.h>
+
+#endif /* __ASM_RANGE_H */
diff -puN /dev/null include/asm-x86_64/range.h
--- /dev/null
+++ a/include/asm-x86_64/range.h
@@ -0,0 +1,6 @@
+#ifndef __ASM_RANGE_H
+#define __ASM_RANGE_H
+
+#include <asm-generic/range.h>
+
+#endif /* __ASM_RANGE_H */
diff -puN /dev/null include/asm-xtensa/range.h
--- /dev/null
+++ a/include/asm-xtensa/range.h
@@ -0,0 +1,6 @@
+#ifndef __ASM_RANGE_H
+#define __ASM_RANGE_H
+
+#include <asm-generic/range.h>
+
+#endif /* __ASM_RANGE_H */
diff -puN include/linux/kernel.h~expose-range-checking-functions-from-arch-specific include/linux/kernel.h
--- a/include/linux/kernel.h~expose-range-checking-functions-from-arch-specific
+++ a/include/linux/kernel.h
@@ -16,6 +16,7 @@
#include <linux/log2.h>
#include <asm/byteorder.h>
#include <asm/bug.h>
+#include <asm/range.h>
extern const char linux_banner[];
extern const char linux_proc_banner[];
@@ -311,6 +312,26 @@ static inline int __attribute__ ((format
(void)__tmp; \
})
+/**
+ * range_within - is one range within another?
+ * @start: the start value
+ * @len: the length from the start
+ * @base: the first valid value
+ * @limit: the first invalid value
+ *
+ * This is usually used for memory range testing. The common cases of
+ * constant 0 start and constant 0 len cases are optimized out.
+ */
+static inline bool range_within(unsigned long start, unsigned long len,
+ unsigned long base, unsigned long limit)
+{
+ if (start < base)
+ return false;
+ if (__builtin_constant_p(len) && len == 0)
+ return start - base <= limit - base;
+ return !val_outside(limit, start, len);
+}
+
struct sysinfo;
extern int do_sysinfo(struct sysinfo *info);
_
Patches currently in -mm which might be from rusty@xxxxxxxxxxxxxxx are
vmi-paravirt-ops-bugfix-for-2621.patch
git-kbuild.patch
git-net.patch
rename-the-parainstructions-symbols-to-be-consistent-with-the-others.patch
allow-boot-time-disable-of-paravirt_ops-patching.patch
allow-per-cpu-variables-to-be-page-aligned.patch
xfs-clean-up-shrinker-games.patch
mm-clean-up-and-kernelify-shrinker-registration.patch
array_size-check-for-type.patch
array_size-check-for-type-uml-fix.patch
module-use-krealloc.patch
extend-print_symbol-capability.patch
extend-print_symbol-capability-fix.patch
futex-restartable-futex_wait.patch
futex-restartable-futex_wait-fix.patch
add-ability-to-keep-track-of-callers-of-symbol_getput.patch
add-ability-to-keep-track-of-callers-of-symbol_getput-update.patch
update-mtd-use-of-symbol_getput.patch
update-dvb-use-of-symbol_getput.patch
simplify-module_get_kallsym-by-dropping-length-arg.patch
fix-race-between-rmmod-and-cat-proc-kallsyms.patch
simplify-kallsyms_lookup.patch
fix-race-between-cat-proc-wchan-and-rmmod-et-al.patch
fix-race-between-cat-proc-slab_allocators-and-rmmod.patch
expose-range-checking-functions-from-arch-specific.patch
____call_usermodehelper-dont-flush_signals.patch
mm-clean-up-and-kernelify-shrinker-registration-reiser4.patch
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