diff --git a/Documentation/security/hardened-atomic.txt b/Documentation/security/hardened-atomic.txt
new file mode 100644
index 0000000..c17131e
--- /dev/null
+++ b/Documentation/security/hardened-atomic.txt
@@ -0,0 +1,141 @@
+=====================
+KSPP: HARDENED_ATOMIC
+=====================
+
+Risks/Vulnerabilities Addressed
+===============================
+
+The Linux Kernel Self Protection Project (KSPP) was created with a mandate
+to eliminate classes of kernel bugs. The class of vulnerabilities addressed
+by HARDENED_ATOMIC is known as use-after-free vulnerabilities.
+
+HARDENED_ATOMIC is based off of work done by the PaX Team [1].  The feature
+on which HARDENED_ATOMIC is based is called PAX_REFCOUNT in the original 
+PaX patch.
+
+Use-after-free Vulnerabilities
+------------------------------
+Use-after-free vulnerabilities are aptly named: they are classes of bugs in
+which an attacker is able to gain control of a piece of memory after it has
+already been freed and use this memory for nefarious purposes: introducing
+malicious code into the address space of an existing process, redirecting
+the flow of execution, etc.
+
+While use-after-free vulnerabilities can arise in a variety of situations, 
+the use case addressed by HARDENED_ATOMIC is that of referenced counted 
+objects.  The kernel can only safely free these objects when all existing 
+users of these objects are finished using them.  This necessitates the 
+introduction of some sort of accounting system to keep track of current
+users of kernel objects.  Reference counters and get()/put() APIs are the 
+means typically chosen to do this: calls to get() increment the reference
+counter, put() decrments it.  When the value of the reference counter
+becomes some sentinel (typically 0), the kernel can safely free the counted
+object.  
+
+Problems arise when the reference counter gets overflowed.  If the reference
+counter is represented with a signed integer type, overflowing the reference
+counter causes it to go from INT_MAX to INT_MIN, then approach 0.  Depending
+on the logic, the transition to INT_MIN may be enough to trigger the bug,
+but when the reference counter becomes 0, the kernel will free the
+underlying object guarded by the reference counter while it still has valid
+users.
+
+
+HARDENED_ATOMIC Design
+======================
+
+HARDENED_ATOMIC provides its protections by modifying the data type used in
+the Linux kernel to implement reference counters: atomic_t. atomic_t is a
+type that contains an integer type, used for counting. HARDENED_ATOMIC
+modifies atomic_t and its associated API so that the integer type contained
+inside of atomic_t cannot be overflowed.
+
+A key point to remember about HARDENED_ATOMIC is that, once enabled, it 
+protects all users of atomic_t without any additional code changes. The
+protection provided by HARDENED_ATOMIC is not “opt-in”: since atomic_t is so
+widely misused, it must be protected as-is. HARDENED_ATOMIC protects all
+users of atomic_t and atomic_long_t against overflow. New users wishing to
+use atomic types, but not needing protection against overflows, should use
+the new types introduced by this series: atomic_wrap_t and
+atomic_long_wrap_t.
+
+Detect/Mitigate
+---------------
+The mechanism of HARDENED_ATOMIC can be viewed as a bipartite process:
+detection of an overflow and mitigating the effects of the overflow, either
+by not performing or performing, then reversing, the operation that caused
+the overflow.
+
+Overflow detection is architecture-specific. Details of the approach used to
+detect overflows on each architecture can be found in the PAX_REFCOUNT
+documentation. [1]
+
+Once an overflow has been detected, HARDENED_ATOMIC mitigates the overflow
+by either reverting the operation or simply not writing the result of the
+operation to memory.
+
+
+HARDENED_ATOMIC Implementation
+==============================
+
+As mentioned above, HARDENED_ATOMIC modifies the atomic_t API to provide its
+protections. Following is a description of the functions that have been
+modified.
+
+First, the type atomic_wrap_t needs to be defined for those kernel users who
+want an atomic type that may be allowed to overflow/wrap (e.g. statistical
+counters). Otherwise, the built-in protections (and associated costs) for
+atomic_t would erroneously apply to these non-reference counter users of
+atomic_t:
+
+  * include/linux/types.h: define atomic_wrap_t and atomic64_wrap_t
+
+Next, we define the mechanism for reporting an overflow of a protected 
+atomic type:
+
+  * kernel/panic.c: void hardened_atomic_overflow(struct pt_regs)
+
+The following functions are an extension of the atomic_t API, supporting
+this new “wrappable” type:
+
+  * static inline int atomic_read_wrap()
+  * static inline void atomic_set_wrap()
+  * static inline void atomic_inc_wrap()
+  * static inline void atomic_dec_wrap()
+  * static inline void atomic_add_wrap()
+  * static inline long atomic_inc_return_wrap()
+
+Departures from Original PaX Implementation
+-------------------------------------------
+While HARDENED_ATOMIC is based largely upon the work done by PaX in their
+original PAX_REFCOUNT patchset, HARDENED_ATOMIC does in fact have a few
+minor differences. We will be posting them here as final decisions are made
+regarding how certain core protections are implemented.
+
+x86 Race Condition
+------------------
+In the original implementation of PAX_REFCOUNT, a known race condition
+exists when performing atomic add operations.  The crux of the problem lies
+in the fact that, on x86, there is no way to know a priori whether a 
+prospective atomic operation will result in an overflow.  To detect an
+overflow, PAX_REFCOUNT had to perform an operation then check if the 
+operation caused an overflow.  
+
+Therefore, there exists a set of conditions in which, given the correct
+timing of threads, an overflowed counter could be visible to a processor.
+If multiple threads execute in such a way so that one thread overflows the
+counter with an addition operation, while a second thread executes another
+addition operation on the same counter before the first thread is able to
+revert the previously executed addition operation (by executing a
+subtraction operation of the same (or greater) magnitude), the counter will
+have been incremented to a value greater than INT_MAX. At this point, the
+protection provided by PAX_REFCOUNT has been bypassed, as further increments
+to the counter will not be detected by the processor’s overflow detection
+mechanism.
+
+The likelihood of an attacker being able to exploit this race was 
+sufficiently insignificant such that fixing the race would be
+counterproductive. 
+
+[1] https://pax.grsecurity.net
+[2] https://forums.grsecurity.net/viewtopic.php?f=7&t=4173
diff --git a/include/asm-generic/atomic-long.h b/include/asm-generic/atomic-long.h
index 288cc9e..425f34b 100644
--- a/include/asm-generic/atomic-long.h
+++ b/include/asm-generic/atomic-long.h
@@ -22,6 +22,12 @@
 
 typedef atomic64_t atomic_long_t;
 
+#ifdef CONFIG_HARDENED_ATOMIC
+typedef atomic64_wrap_t atomic_long_wrap_t;
+#else
+typedef atomic64_t atomic_long_wrap_t;
+#endif
+
 #define ATOMIC_LONG_INIT(i)	ATOMIC64_INIT(i)
 #define ATOMIC_LONG_PFX(x)	atomic64 ## x
 
@@ -29,51 +35,77 @@ typedef atomic64_t atomic_long_t;
 
 typedef atomic_t atomic_long_t;
 
+#ifdef CONFIG_HARDENED_ATOMIC
+typedef atomic_wrap_t atomic_long_wrap_t;
+#else
+typedef atomic_t atomic_long_wrap_t;
+#endif
+
 #define ATOMIC_LONG_INIT(i)	ATOMIC_INIT(i)
 #define ATOMIC_LONG_PFX(x)	atomic ## x
 
 #endif
 
-#define ATOMIC_LONG_READ_OP(mo)						\
-static inline long atomic_long_read##mo(const atomic_long_t *l)		\
+#define ATOMIC_LONG_READ_OP(mo, suffix)						\
+static inline long atomic_long_read##mo##suffix(const atomic_long##suffix##_t *l)\
 {									\
-	ATOMIC_LONG_PFX(_t) *v = (ATOMIC_LONG_PFX(_t) *)l;		\
+	ATOMIC_LONG_PFX(suffix##_t) *v = (ATOMIC_LONG_PFX(suffix##_t) *)l;\
 									\
-	return (long)ATOMIC_LONG_PFX(_read##mo)(v);			\
+	return (long)ATOMIC_LONG_PFX(_read##mo##suffix)(v);		\
 }
-ATOMIC_LONG_READ_OP()
-ATOMIC_LONG_READ_OP(_acquire)
+ATOMIC_LONG_READ_OP(,)
+ATOMIC_LONG_READ_OP(_acquire,)
+
+#ifdef CONFIG_HARDENED_ATOMIC
+ATOMIC_LONG_READ_OP(,_wrap)
+#else /* CONFIG_HARDENED_ATOMIC */
+#define atomic_long_read_wrap(v) atomic_long_read((v))
+#endif /* CONFIG_HARDENED_ATOMIC */
 
 #undef ATOMIC_LONG_READ_OP
 
-#define ATOMIC_LONG_SET_OP(mo)						\
-static inline void atomic_long_set##mo(atomic_long_t *l, long i)	\
+#define ATOMIC_LONG_SET_OP(mo, suffix)					\
+static inline void atomic_long_set##mo##suffix(atomic_long##suffix##_t *l, long i)\
 {									\
-	ATOMIC_LONG_PFX(_t) *v = (ATOMIC_LONG_PFX(_t) *)l;		\
+	ATOMIC_LONG_PFX(suffix##_t) *v = (ATOMIC_LONG_PFX(suffix##_t) *)l;\
 									\
-	ATOMIC_LONG_PFX(_set##mo)(v, i);				\
+	ATOMIC_LONG_PFX(_set##mo##suffix)(v, i);			\
 }
-ATOMIC_LONG_SET_OP()
-ATOMIC_LONG_SET_OP(_release)
+ATOMIC_LONG_SET_OP(,)
+ATOMIC_LONG_SET_OP(_release,)
+
+#ifdef CONFIG_HARDENED_ATOMIC
+ATOMIC_LONG_SET_OP(,_wrap)
+#else /* CONFIG_HARDENED_ATOMIC */
+#define atomic_long_set_wrap(v, i) atomic_long_set((v), (i))
+#endif /* CONFIG_HARDENED_ATOMIC */
 
 #undef ATOMIC_LONG_SET_OP
 
-#define ATOMIC_LONG_ADD_SUB_OP(op, mo)					\
+#define ATOMIC_LONG_ADD_SUB_OP(op, mo, suffix)				\
 static inline long							\
-atomic_long_##op##_return##mo(long i, atomic_long_t *l)			\
+atomic_long_##op##_return##mo##suffix(long i, atomic_long##suffix##_t *l)\
 {									\
-	ATOMIC_LONG_PFX(_t) *v = (ATOMIC_LONG_PFX(_t) *)l;		\
+	ATOMIC_LONG_PFX(suffix##_t) *v = (ATOMIC_LONG_PFX(suffix##_t) *)l;\
 									\
-	return (long)ATOMIC_LONG_PFX(_##op##_return##mo)(i, v);		\
+	return (long)ATOMIC_LONG_PFX(_##op##_return##mo##suffix)(i, v);\
 }
-ATOMIC_LONG_ADD_SUB_OP(add,)
-ATOMIC_LONG_ADD_SUB_OP(add, _relaxed)
-ATOMIC_LONG_ADD_SUB_OP(add, _acquire)
-ATOMIC_LONG_ADD_SUB_OP(add, _release)
-ATOMIC_LONG_ADD_SUB_OP(sub,)
-ATOMIC_LONG_ADD_SUB_OP(sub, _relaxed)
-ATOMIC_LONG_ADD_SUB_OP(sub, _acquire)
-ATOMIC_LONG_ADD_SUB_OP(sub, _release)
+ATOMIC_LONG_ADD_SUB_OP(add,,)
+ATOMIC_LONG_ADD_SUB_OP(add, _relaxed,)
+ATOMIC_LONG_ADD_SUB_OP(add, _acquire,)
+ATOMIC_LONG_ADD_SUB_OP(add, _release,)
+ATOMIC_LONG_ADD_SUB_OP(sub,,)
+ATOMIC_LONG_ADD_SUB_OP(sub, _relaxed,)
+ATOMIC_LONG_ADD_SUB_OP(sub, _acquire,)
+ATOMIC_LONG_ADD_SUB_OP(sub, _release,)
+
+#ifdef CONFIG_HARDENED_ATOMIC
+ATOMIC_LONG_ADD_SUB_OP(add,,_wrap)
+ATOMIC_LONG_ADD_SUB_OP(sub,,_wrap)
+#else /* CONFIG_HARDENED_ATOMIC */
+#define atomic_long_add_return_wrap(i,v) atomic_long_add_return((i), (v))
+#define atomic_long_sub_return_wrap(i,v) atomic_long_sub_return((i), (v))
+#endif /* CONFIG_HARDENED_ATOMIC */
 
 #undef ATOMIC_LONG_ADD_SUB_OP
 
@@ -89,6 +121,13 @@ ATOMIC_LONG_ADD_SUB_OP(sub, _release)
 #define atomic_long_cmpxchg(l, old, new) \
 	(ATOMIC_LONG_PFX(_cmpxchg)((ATOMIC_LONG_PFX(_t) *)(l), (old), (new)))
 
+#ifdef CONFIG_HARDENED_ATOMIC
+#define atomic_long_cmpxchg_wrap(l, old, new) \
+	(ATOMIC_LONG_PFX(_cmpxchg_wrap)((ATOMIC_LONG_PFX(_wrap_t) *)(l), (old), (new)))
+#else /* CONFIG_HARDENED_ATOMIC */
+#define atomic_long_cmpxchg_wrap(v, o, n) atomic_long_cmpxchg((v), (o), (n))
+#endif /* CONFIG_HARDENED_ATOMIC */
+
 #define atomic_long_xchg_relaxed(v, new) \
 	(ATOMIC_LONG_PFX(_xchg_relaxed)((ATOMIC_LONG_PFX(_t) *)(v), (new)))
 #define atomic_long_xchg_acquire(v, new) \
@@ -98,6 +137,13 @@ ATOMIC_LONG_ADD_SUB_OP(sub, _release)
 #define atomic_long_xchg(v, new) \
 	(ATOMIC_LONG_PFX(_xchg)((ATOMIC_LONG_PFX(_t) *)(v), (new)))
 
+#ifdef CONFIG_HARDENED_ATOMIC
+#define atomic_long_xchg_wrap(v, new) \
+	(ATOMIC_LONG_PFX(_xchg_wrap)((ATOMIC_LONG_PFX(_wrap_t) *)(v), (new)))
+#else /* CONFIG_HARDENED_ATOMIC */
+#define atomic_long_xchg_wrap(v, i) atomic_long_xchg((v), (i))
+#endif /* CONFIG_HARDENED_ATOMIC */
+
 static __always_inline void atomic_long_inc(atomic_long_t *l)
 {
 	ATOMIC_LONG_PFX(_t) *v = (ATOMIC_LONG_PFX(_t) *)l;
@@ -105,6 +151,17 @@ static __always_inline void atomic_long_inc(atomic_long_t *l)
 	ATOMIC_LONG_PFX(_inc)(v);
 }
 
+#ifdef CONFIG_HARDENED_ATOMIC
+static __always_inline void atomic_long_inc_wrap(atomic_long_wrap_t *l)
+{
+	ATOMIC_LONG_PFX(_wrap_t) *v = (ATOMIC_LONG_PFX(_wrap_t) *)l;
+
+	ATOMIC_LONG_PFX(_inc_wrap)(v);
+}
+#else
+#define atomic_long_inc_wrap(v) atomic_long_inc(v)
+#endif
+
 static __always_inline void atomic_long_dec(atomic_long_t *l)
 {
 	ATOMIC_LONG_PFX(_t) *v = (ATOMIC_LONG_PFX(_t) *)l;
@@ -112,6 +169,17 @@ static __always_inline void atomic_long_dec(atomic_long_t *l)
 	ATOMIC_LONG_PFX(_dec)(v);
 }
 
+#ifdef CONFIG_HARDENED_ATOMIC
+static __always_inline void atomic_long_dec_wrap(atomic_long_wrap_t *l)
+{
+	ATOMIC_LONG_PFX(_wrap_t) *v = (ATOMIC_LONG_PFX(_wrap_t) *)l;
+
+	ATOMIC_LONG_PFX(_dec_wrap)(v);
+}
+#else
+#define atomic_long_dec_wrap(v) atomic_long_dec(v)
+#endif
+
 #define ATOMIC_LONG_FETCH_OP(op, mo)					\
 static inline long							\
 atomic_long_fetch_##op##mo(long i, atomic_long_t *l)			\
@@ -168,21 +236,29 @@ ATOMIC_LONG_FETCH_INC_DEC_OP(dec, _release)
 
 #undef ATOMIC_LONG_FETCH_INC_DEC_OP
 
-#define ATOMIC_LONG_OP(op)						\
+#define ATOMIC_LONG_OP(op, suffix)					\
 static __always_inline void						\
-atomic_long_##op(long i, atomic_long_t *l)				\
+atomic_long_##op##suffix(long i, atomic_long##suffix##_t *l)		\
 {									\
-	ATOMIC_LONG_PFX(_t) *v = (ATOMIC_LONG_PFX(_t) *)l;		\
+	ATOMIC_LONG_PFX(suffix##_t) *v = (ATOMIC_LONG_PFX(suffix##_t) *)l;\
 									\
-	ATOMIC_LONG_PFX(_##op)(i, v);					\
+	ATOMIC_LONG_PFX(_##op##suffix)(i, v);				\
 }
 
-ATOMIC_LONG_OP(add)
-ATOMIC_LONG_OP(sub)
-ATOMIC_LONG_OP(and)
-ATOMIC_LONG_OP(andnot)
-ATOMIC_LONG_OP(or)
-ATOMIC_LONG_OP(xor)
+ATOMIC_LONG_OP(add,)
+ATOMIC_LONG_OP(sub,)
+ATOMIC_LONG_OP(and,)
+ATOMIC_LONG_OP(or,)
+ATOMIC_LONG_OP(xor,)
+ATOMIC_LONG_OP(andnot,)
+
+#ifdef CONFIG_HARDENED_ATOMIC
+ATOMIC_LONG_OP(add,_wrap)
+ATOMIC_LONG_OP(sub,_wrap)
+#else /* CONFIG_HARDENED_ATOMIC */
+#define atomic_long_add_wrap(i,v) atomic_long_add((i),(v))
+#define atomic_long_sub_wrap(i,v) atomic_long_sub((i),(v))
+#endif /* CONFIG_HARDENED_ATOMIC */
 
 #undef ATOMIC_LONG_OP
 
@@ -193,6 +269,15 @@ static inline int atomic_long_sub_and_test(long i, atomic_long_t *l)
 	return ATOMIC_LONG_PFX(_sub_and_test)(i, v);
 }
 
+/*
+static inline int atomic_long_add_and_test(long i, atomic_long_t *l)
+{
+	ATOMIC_LONG_PFX(_t) *v = (ATOMIC_LONG_PFX(_t) *)l;
+
+	return ATOMIC_LONG_PFX(_add_and_test)(i, v);
+}
+*/
+
 static inline int atomic_long_dec_and_test(atomic_long_t *l)
 {
 	ATOMIC_LONG_PFX(_t) *v = (ATOMIC_LONG_PFX(_t) *)l;
@@ -214,22 +299,75 @@ static inline int atomic_long_add_negative(long i, atomic_long_t *l)
 	return ATOMIC_LONG_PFX(_add_negative)(i, v);
 }
 
-#define ATOMIC_LONG_INC_DEC_OP(op, mo)					\
+#ifdef CONFIG_HARDENED_ATOMIC
+static inline int atomic_long_sub_and_test_wrap(long i, atomic_long_wrap_t *l)
+{
+	ATOMIC_LONG_PFX(_wrap_t) *v = (ATOMIC_LONG_PFX(_wrap_t) *)l;
+
+	return ATOMIC_LONG_PFX(_sub_and_test_wrap)(i, v);
+}
+
+
+static inline int atomic_long_add_and_test_wrap(long i, atomic_long_wrap_t *l)
+{
+	ATOMIC_LONG_PFX(_wrap_t) *v = (ATOMIC_LONG_PFX(_wrap_t) *)l;
+
+	return ATOMIC_LONG_PFX(_add_and_test_wrap)(i, v);
+}
+
+
+static inline int atomic_long_dec_and_test_wrap(atomic_long_wrap_t *l)
+{
+	ATOMIC_LONG_PFX(_wrap_t) *v = (ATOMIC_LONG_PFX(_wrap_t) *)l;
+
+	return ATOMIC_LONG_PFX(_dec_and_test_wrap)(v);
+}
+
+static inline int atomic_long_inc_and_test_wrap(atomic_long_wrap_t *l)
+{
+	ATOMIC_LONG_PFX(_wrap_t) *v = (ATOMIC_LONG_PFX(_wrap_t) *)l;
+
+	return ATOMIC_LONG_PFX(_inc_and_test_wrap)(v);
+}
+
+static inline int atomic_long_add_negative_wrap(long i, atomic_long_wrap_t *l)
+{
+	ATOMIC_LONG_PFX(_wrap_t) *v = (ATOMIC_LONG_PFX(_wrap_t) *)l;
+
+	return ATOMIC_LONG_PFX(_add_negative_wrap)(i, v);
+}
+#else /* CONFIG_HARDENED_ATOMIC */
+#define atomic_long_sub_and_test_wrap(i, v) atomic_long_sub_and_test((i), (v))
+#define atomic_long_add_and_test_wrap(i, v) atomic_long_add_and_test((i), (v))
+#define atomic_long_dec_and_test_wrap(i, v) atomic_long_dec_and_test((i), (v))
+#define atomic_long_inc_and_test_wrap(i, v) atomic_long_inc_and_test((i), (v))
+#define atomic_long_add_negative_wrap(i, v) atomic_long_add_negative((i), (v))
+#endif /* CONFIG_HARDENED_ATOMIC */
+
+#define ATOMIC_LONG_INC_DEC_OP(op, mo, suffix)				\
 static inline long							\
-atomic_long_##op##_return##mo(atomic_long_t *l)				\
+atomic_long_##op##_return##mo##suffix(atomic_long##suffix##_t *l)	\
 {									\
-	ATOMIC_LONG_PFX(_t) *v = (ATOMIC_LONG_PFX(_t) *)l;		\
+	ATOMIC_LONG_PFX(suffix##_t) *v = (ATOMIC_LONG_PFX(suffix##_t) *)l;\
 									\
-	return (long)ATOMIC_LONG_PFX(_##op##_return##mo)(v);		\
+	return (long)ATOMIC_LONG_PFX(_##op##_return##mo##suffix)(v);	\
 }
-ATOMIC_LONG_INC_DEC_OP(inc,)
-ATOMIC_LONG_INC_DEC_OP(inc, _relaxed)
-ATOMIC_LONG_INC_DEC_OP(inc, _acquire)
-ATOMIC_LONG_INC_DEC_OP(inc, _release)
-ATOMIC_LONG_INC_DEC_OP(dec,)
-ATOMIC_LONG_INC_DEC_OP(dec, _relaxed)
-ATOMIC_LONG_INC_DEC_OP(dec, _acquire)
-ATOMIC_LONG_INC_DEC_OP(dec, _release)
+ATOMIC_LONG_INC_DEC_OP(inc,,)
+ATOMIC_LONG_INC_DEC_OP(inc, _relaxed,)
+ATOMIC_LONG_INC_DEC_OP(inc, _acquire,)
+ATOMIC_LONG_INC_DEC_OP(inc, _release,)
+ATOMIC_LONG_INC_DEC_OP(dec,,)
+ATOMIC_LONG_INC_DEC_OP(dec, _relaxed,)
+ATOMIC_LONG_INC_DEC_OP(dec, _acquire,)
+ATOMIC_LONG_INC_DEC_OP(dec, _release,)
+
+#ifdef CONFIG_HARDENED_ATOMIC
+ATOMIC_LONG_INC_DEC_OP(inc,,_wrap)
+ATOMIC_LONG_INC_DEC_OP(dec,,_wrap)
+#else /* CONFIG_HARDENED_ATOMIC */
+#define atomic_long_inc_return_wrap(v) atomic_long_inc_return((v))
+#define atomic_long_dec_return_wrap(v) atomic_long_dec_return((v))
+#endif /*  CONFIG_HARDENED_ATOMIC */
 
 #undef ATOMIC_LONG_INC_DEC_OP
 
@@ -240,7 +378,41 @@ static inline long atomic_long_add_unless(atomic_long_t *l, long a, long u)
 	return (long)ATOMIC_LONG_PFX(_add_unless)(v, a, u);
 }
 
+#ifdef CONFIG_HARDENED_ATOMIC
+static inline long atomic_long_add_unless_wrap(atomic_long_wrap_t *l, long a, long u)
+{
+	ATOMIC_LONG_PFX(_wrap_t) *v = (ATOMIC_LONG_PFX(_wrap_t) *)l;
+
+	return (long)ATOMIC_LONG_PFX(_add_unless_wrap)(v, a, u);
+}
+#else /* CONFIG_HARDENED_ATOMIC */
+#define atomic_long_add_unless_wrap(v, i, j) atomic_long_add_unless((v), (i), (j))
+#endif /* CONFIG_HARDENED_ATOMIC */
+
 #define atomic_long_inc_not_zero(l) \
 	ATOMIC_LONG_PFX(_inc_not_zero)((ATOMIC_LONG_PFX(_t) *)(l))
 
+#ifndef CONFIG_HARDENED_ATOMIC
+#define atomic_read_wrap(v) atomic_read(v)
+#define atomic_set_wrap(v, i) atomic_set((v), (i))
+#define atomic_add_wrap(i, v) atomic_add((i), (v))
+#define atomic_sub_wrap(i, v) atomic_sub((i), (v))
+#define atomic_inc_wrap(v) atomic_inc(v)
+#define atomic_dec_wrap(v) atomic_dec(v)
+#define atomic_add_return_wrap(i, v) atomic_add_return((i), (v))
+#define atomic_sub_return_wrap(i, v) atomic_sub_return((i), (v))
+#define atoimc_dec_return_wrap(v) atomic_dec_return(v)
+#ifndef atomic_inc_return_wrap
+#define atomic_inc_return_wrap(v) atomic_inc_return(v)
+#endif /* atomic_inc_return */
+#define atomic_dec_and_test_wrap(v) atomic_dec_and_test(v)
+#define atomic_inc_and_test_wrap(v) atomic_inc_and_test(v)
+#define atomic_add_and_test_wrap(i, v) atomic_add_and_test((v), (i))
+#define atomic_sub_and_test_wrap(i, v) atomic_sub_and_test((v), (i))
+#define atomic_xchg_wrap(v, i) atomic_xchg((v), (i))
+#define atomic_cmpxchg_wrap(v, o, n) atomic_cmpxchg((v), (o), (n))
+#define atomic_add_negative_wrap(i, v) atomic_add_negative((i), (v))
+#define atomic_add_unless_wrap(v, i, j) atomic_add_unless((v), (i), (j))
+#endif /* CONFIG_HARDENED_ATOMIC */
+
 #endif  /*  _ASM_GENERIC_ATOMIC_LONG_H  */
diff --git a/include/asm-generic/atomic.h b/include/asm-generic/atomic.h
index 9ed8b98..6c3ed48 100644
--- a/include/asm-generic/atomic.h
+++ b/include/asm-generic/atomic.h
@@ -177,6 +177,10 @@ ATOMIC_OP(xor, ^)
 #define atomic_read(v)	READ_ONCE((v)->counter)
 #endif
 
+#ifndef atomic_read_wrap
+#define atomic_read_wrap(v)	READ_ONCE((v)->counter)
+#endif
+
 /**
  * atomic_set - set atomic variable
  * @v: pointer of type atomic_t
@@ -186,6 +190,10 @@ ATOMIC_OP(xor, ^)
  */
 #define atomic_set(v, i) WRITE_ONCE(((v)->counter), (i))
 
+#ifndef atomic_set_wrap
+#define atomic_set_wrap(v, i) WRITE_ONCE(((v)->counter), (i))
+#endif
+
 #include <linux/irqflags.h>
 
 static inline int atomic_add_negative(int i, atomic_t *v)
@@ -193,33 +201,72 @@ static inline int atomic_add_negative(int i, atomic_t *v)
 	return atomic_add_return(i, v) < 0;
 }
 
+static inline int atomic_add_negative_wrap(int i, atomic_wrap_t *v)
+{
+	return atomic_add_return_wrap(i, v) < 0;
+}
+
 static inline void atomic_add(int i, atomic_t *v)
 {
 	atomic_add_return(i, v);
 }
 
+static inline void atomic_add_wrap(int i, atomic_wrap_t *v)
+{
+	atomic_add_return_wrap(i, v);
+}
+
 static inline void atomic_sub(int i, atomic_t *v)
 {
 	atomic_sub_return(i, v);
 }
 
+static inline void atomic_sub_wrap(int i, atomic_wrap_t *v)
+{
+	atomic_sub_return_wrap(i, v);
+}
+
 static inline void atomic_inc(atomic_t *v)
 {
 	atomic_add_return(1, v);
 }
 
+static inline void atomic_inc_wrap(atomic_wrap_t *v)
+{
+	atomic_add_return_wrap(1, v);
+}
+
 static inline void atomic_dec(atomic_t *v)
 {
 	atomic_sub_return(1, v);
 }
 
+static inline void atomic_dec_wrap(atomic_wrap_t *v)
+{
+	atomic_sub_return_wrap(1, v);
+}
+
 #define atomic_dec_return(v)		atomic_sub_return(1, (v))
 #define atomic_inc_return(v)		atomic_add_return(1, (v))
 
+#define atomic_add_and_test(i, v)	(atomic_add_return((i), (v)) == 0)
 #define atomic_sub_and_test(i, v)	(atomic_sub_return((i), (v)) == 0)
 #define atomic_dec_and_test(v)		(atomic_dec_return(v) == 0)
 #define atomic_inc_and_test(v)		(atomic_inc_return(v) == 0)
 
+#ifndef atomic_add_and_test_wrap
+#define atomic_add_and_test_wrap(i, v)	(atomic_add_return_wrap((i), (v)) == 0)
+#endif
+#ifndef atomic_sub_and_test_wrap
+#define atomic_sub_and_test_wrap(i, v)	(atomic_sub_return_wrap((i), (v)) == 0)
+#endif
+#ifndef atomic_dec_and_test_wrap
+#define atomic_dec_and_test_wrap(v)		(atomic_dec_return_wrap(v) == 0)
+#endif
+#ifndef atomic_inc_and_test_wrap
+#define atomic_inc_and_test_wrap(v)		(atomic_inc_return_wrap(v) == 0)
+#endif
+
 #define atomic_xchg(ptr, v)		(xchg(&(ptr)->counter, (v)))
 #define atomic_cmpxchg(v, old, new)	(cmpxchg(&((v)->counter), (old), (new)))
 
@@ -232,4 +279,13 @@ static inline int __atomic_add_unless(atomic_t *v, int a, int u)
 	return c;
 }
 
+static inline int __atomic_add_unless_wrap(atomic_wrap_t *v, int a, int u)
+{
+	int c, old;
+	c = atomic_read_wrap(v);
+	while (c != u && (old = atomic_cmpxchg_wrap(v, c, c + a)) != c)
+		c = old;
+	return c;
+}
+
 #endif /* __ASM_GENERIC_ATOMIC_H */
diff --git a/include/asm-generic/atomic64.h b/include/asm-generic/atomic64.h
index dad68bf..0bb63b9 100644
--- a/include/asm-generic/atomic64.h
+++ b/include/asm-generic/atomic64.h
@@ -56,10 +56,23 @@ extern int	 atomic64_add_unless(atomic64_t *v, long long a, long long u);
 #define atomic64_inc(v)			atomic64_add(1LL, (v))
 #define atomic64_inc_return(v)		atomic64_add_return(1LL, (v))
 #define atomic64_inc_and_test(v) 	(atomic64_inc_return(v) == 0)
+#define atomic64_add_and_test(a, v)	(atomic64_add_return((a), (v)) == 0)
 #define atomic64_sub_and_test(a, v)	(atomic64_sub_return((a), (v)) == 0)
 #define atomic64_dec(v)			atomic64_sub(1LL, (v))
 #define atomic64_dec_return(v)		atomic64_sub_return(1LL, (v))
 #define atomic64_dec_and_test(v)	(atomic64_dec_return((v)) == 0)
 #define atomic64_inc_not_zero(v) 	atomic64_add_unless((v), 1LL, 0LL)
 
+#define atomic64_read_wrap(v) atomic64_read(v)
+#define atomic64_set_wrap(v, i) atomic64_set((v), (i))
+#define atomic64_add_wrap(a, v) atomic64_add((a), (v))
+#define atomic64_add_return_wrap(a, v) atomic64_add_return((a), (v))
+#define atomic64_sub_wrap(a, v) atomic64_sub((a), (v))
+#define atomic64_inc_wrap(v) atomic64_inc(v)
+#define atomic64_inc_return_wrap(v) atomic64_inc_return(v)
+#define atomic64_dec_wrap(v) atomic64_dec(v)
+#define atomic64_dec_return_wrap(v) atomic64_return_dec(v)
+#define atomic64_cmpxchg_wrap(v, o, n) atomic64_cmpxchg((v), (o), (n))
+#define atomic64_xchg_wrap(v, n) atomic64_xchg((v), (n))
+
 #endif  /*  _ASM_GENERIC_ATOMIC64_H  */
diff --git a/include/asm-generic/bug.h b/include/asm-generic/bug.h
index 6f96247..20ce604 100644
--- a/include/asm-generic/bug.h
+++ b/include/asm-generic/bug.h
@@ -215,6 +215,13 @@ void __warn(const char *file, int line, void *caller, unsigned taint,
 # define WARN_ON_SMP(x)			({0;})
 #endif
 
+#ifdef CONFIG_HARDENED_ATOMIC
+void hardened_atomic_overflow(struct pt_regs *regs);
+#else
+static inline void hardened_atomic_overflow(struct pt_regs *regs){
+}
+#endif
+
 #endif /* __ASSEMBLY__ */
 
 #endif
diff --git a/include/asm-generic/local.h b/include/asm-generic/local.h
index 9ceb03b..a98ad1d 100644
--- a/include/asm-generic/local.h
+++ b/include/asm-generic/local.h
@@ -23,24 +23,39 @@ typedef struct
 	atomic_long_t a;
 } local_t;
 
+typedef struct {
+	atomic_long_wrap_t a;
+} local_wrap_t;
+
 #define LOCAL_INIT(i)	{ ATOMIC_LONG_INIT(i) }
 
 #define local_read(l)	atomic_long_read(&(l)->a)
+#define local_read_wrap(l)	atomic_long_read_wrap(&(l)->a)
 #define local_set(l,i)	atomic_long_set((&(l)->a),(i))
+#define local_set_wrap(l,i)	atomic_long_set_wrap((&(l)->a),(i))
 #define local_inc(l)	atomic_long_inc(&(l)->a)
+#define local_inc_wrap(l)	atomic_long_inc_wrap(&(l)->a)
 #define local_dec(l)	atomic_long_dec(&(l)->a)
+#define local_dec_wrap(l)	atomic_long_dec_wrap(&(l)->a)
 #define local_add(i,l)	atomic_long_add((i),(&(l)->a))
+#define local_add_wrap(i,l)	atomic_long_add_wrap((i),(&(l)->a))
 #define local_sub(i,l)	atomic_long_sub((i),(&(l)->a))
+#define local_sub_wrap(i,l)	atomic_long_sub_wrap((i),(&(l)->a))
 
 #define local_sub_and_test(i, l) atomic_long_sub_and_test((i), (&(l)->a))
+#define local_sub_and_test_wrap(i, l) atomic_long_sub_and_test_wrap((i), (&(l)->a))
 #define local_dec_and_test(l) atomic_long_dec_and_test(&(l)->a)
 #define local_inc_and_test(l) atomic_long_inc_and_test(&(l)->a)
 #define local_add_negative(i, l) atomic_long_add_negative((i), (&(l)->a))
 #define local_add_return(i, l) atomic_long_add_return((i), (&(l)->a))
+#define local_add_return_wrap(i, l) atomic_long_add_return_wrap((i), (&(l)->a))
 #define local_sub_return(i, l) atomic_long_sub_return((i), (&(l)->a))
 #define local_inc_return(l) atomic_long_inc_return(&(l)->a)
+/* verify that below function is needed */
+#define local_dec_return(l) atomic_long_dec_return(&(l)->a)
 
 #define local_cmpxchg(l, o, n) atomic_long_cmpxchg((&(l)->a), (o), (n))
+#define local_cmpxchg_wrap(l, o, n) atomic_long_cmpxchg_wrap((&(l)->a), (o), (n))
 #define local_xchg(l, n) atomic_long_xchg((&(l)->a), (n))
 #define local_add_unless(l, _a, u) atomic_long_add_unless((&(l)->a), (_a), (u))
 #define local_inc_not_zero(l) atomic_long_inc_not_zero(&(l)->a)
diff --git a/include/linux/atomic.h b/include/linux/atomic.h
index e71835b..3cb48f0 100644
--- a/include/linux/atomic.h
+++ b/include/linux/atomic.h
@@ -89,6 +89,11 @@
 #define  atomic_add_return(...)						\
 	__atomic_op_fence(atomic_add_return, __VA_ARGS__)
 #endif
+
+#ifndef atomic_add_return_wrap
+#define atomic_add_return_wrap(...)					\
+	__atomic_op_fence(atomic_add_return_wrap, __VA_ARGS__)
+#endif
 #endif /* atomic_add_return_relaxed */
 
 /* atomic_inc_return_relaxed */
@@ -113,6 +118,11 @@
 #define  atomic_inc_return(...)						\
 	__atomic_op_fence(atomic_inc_return, __VA_ARGS__)
 #endif
+
+#ifndef atomic_inc_return_wrap
+#define  atomic_inc_return_wrap(...)				\
+	__atomic_op_fence(atomic_inc_return_wrap, __VA_ARGS__)
+#endif
 #endif /* atomic_inc_return_relaxed */
 
 /* atomic_sub_return_relaxed */
@@ -137,6 +147,11 @@
 #define  atomic_sub_return(...)						\
 	__atomic_op_fence(atomic_sub_return, __VA_ARGS__)
 #endif
+
+#ifndef atomic_sub_return_wrap
+#define atomic_sub_return_wrap(...)				\
+	__atomic_op_fence(atomic_sub_return_wrap, __VA_ARGS__)
+#endif
 #endif /* atomic_sub_return_relaxed */
 
 /* atomic_dec_return_relaxed */
@@ -161,6 +176,11 @@
 #define  atomic_dec_return(...)						\
 	__atomic_op_fence(atomic_dec_return, __VA_ARGS__)
 #endif
+
+#ifndef atomic_dec_return_wrap
+#define  atomic_dec_return_wrap(...)				\
+	__atomic_op_fence(atomic_dec_return_wrap, __VA_ARGS__)
+#endif
 #endif /* atomic_dec_return_relaxed */
 
 
@@ -397,6 +417,11 @@
 #define  atomic_xchg(...)						\
 	__atomic_op_fence(atomic_xchg, __VA_ARGS__)
 #endif
+
+#ifndef atomic_xchg_wrap
+#define  atomic_xchg_wrap(...)				\
+	_atomic_op_fence(atomic_xchg_wrap, __VA_ARGS__)
+#endif
 #endif /* atomic_xchg_relaxed */
 
 /* atomic_cmpxchg_relaxed */
@@ -421,6 +446,11 @@
 #define  atomic_cmpxchg(...)						\
 	__atomic_op_fence(atomic_cmpxchg, __VA_ARGS__)
 #endif
+
+#ifndef atomic_cmpxchg_wrap
+#define  atomic_cmpxchg_wrap(...)				\
+	_atomic_op_fence(atomic_cmpxchg_wrap, __VA_ARGS__)
+#endif
 #endif /* atomic_cmpxchg_relaxed */
 
 /* cmpxchg_relaxed */
@@ -507,6 +537,22 @@ static inline int atomic_add_unless(atomic_t *v, int a, int u)
 }
 
 /**
+ * atomic_add_unless_wrap - add unless the number is already a given value
+ * @v: pointer of type atomic_wrap_t
+ * @a: the amount to add to v...
+ * @u: ...unless v is equal to u.
+ *
+ * Atomically adds @a to @v, so long as @v was not already @u.
+ * Returns non-zero if @v was not @u, and zero otherwise.
+ */
+#ifdef CONFIG_HARDENED_ATOMIC
+static inline int atomic_add_unless_wrap(atomic_wrap_t *v, int a, int u)
+{
+	return __atomic_add_unless_wrap(v, a, u) != u;
+}
+#endif /* CONFIG_HARDENED_ATOMIC */
+
+/**
  * atomic_inc_not_zero - increment unless the number is zero
  * @v: pointer of type atomic_t
  *
@@ -631,6 +677,43 @@ static inline int atomic_dec_if_positive(atomic_t *v)
 #include <asm-generic/atomic64.h>
 #endif
 
+#ifndef CONFIG_HARDENED_ATOMIC
+#define atomic64_wrap_t atomic64_t
+#ifndef atomic64_read_wrap
+#define atomic64_read_wrap(v)		atomic64_read(v)
+#endif
+#ifndef atomic64_set_wrap
+#define atomic64_set_wrap(v, i)		atomic64_set((v), (i))
+#endif
+#ifndef atomic64_add_wrap
+#define atomic64_add_wrap(a, v)		atomic64_add((a), (v))
+#endif
+#ifndef atomic64_add_return_wrap
+#define atomic64_add_return_wrap(a, v)	atomic64_add_return((a), (v))
+#endif
+#ifndef atomic64_sub_wrap
+#define atomic64_sub_wrap(a, v)		atomic64_sub((a), (v))
+#endif
+#ifndef atomic64_inc_wrap
+#define atomic64_inc_wrap(v)		atomic64_inc((v))
+#endif
+#ifndef atomic64_inc_return_wrap
+#define atomic64_inc_return_wrap(v)	atomic64_inc_return((v))
+#endif
+#ifndef atomic64_dec_wrap
+#define atomic64_dec_wrap(v)		atomic64_dec((v))
+#endif
+#ifndef atomic64_dec_return_wrap
+#define atomic64_dec_return_wrap(v)	atomic64_dec_return((v))
+#endif
+#ifndef atomic64_cmpxchg_wrap
+#define atomic64_cmpxchg_wrap(v, o, n) atomic64_cmpxchg((v), (o), (n))
+#endif
+#ifndef atomic64_xchg_wrap
+#define atomic64_xchg_wrap(v, n) atomic64_xchg((v), (n))
+#endif
+#endif /* CONFIG_HARDENED_ATOMIC */
+
 #ifndef atomic64_read_acquire
 #define  atomic64_read_acquire(v)	smp_load_acquire(&(v)->counter)
 #endif
@@ -661,6 +744,12 @@ static inline int atomic_dec_if_positive(atomic_t *v)
 #define  atomic64_add_return(...)					\
 	__atomic_op_fence(atomic64_add_return, __VA_ARGS__)
 #endif
+
+#ifndef atomic64_add_return_wrap
+#define  atomic64_add_return_wrap(...)				\
+	__atomic_op_fence(atomic64_add_return_wrap, __VA_ARGS__)
+#endif
+
 #endif /* atomic64_add_return_relaxed */
 
 /* atomic64_inc_return_relaxed */
@@ -685,6 +774,11 @@ static inline int atomic_dec_if_positive(atomic_t *v)
 #define  atomic64_inc_return(...)					\
 	__atomic_op_fence(atomic64_inc_return, __VA_ARGS__)
 #endif
+
+#ifndef atomic64_inc_return_wrap
+#define  atomic64_inc_return_wrap(...)				\
+	__atomic_op_fence(atomic64_inc_return_wrap, __VA_ARGS__)
+#endif
 #endif /* atomic64_inc_return_relaxed */
 
 
@@ -710,6 +804,11 @@ static inline int atomic_dec_if_positive(atomic_t *v)
 #define  atomic64_sub_return(...)					\
 	__atomic_op_fence(atomic64_sub_return, __VA_ARGS__)
 #endif
+
+#ifndef atomic64_sub_return_wrap
+#define  atomic64_sub_return_wrap(...)				\
+	__atomic_op_fence(atomic64_sub_return_wrap, __VA_ARGS__)
+#endif
 #endif /* atomic64_sub_return_relaxed */
 
 /* atomic64_dec_return_relaxed */
@@ -734,6 +833,11 @@ static inline int atomic_dec_if_positive(atomic_t *v)
 #define  atomic64_dec_return(...)					\
 	__atomic_op_fence(atomic64_dec_return, __VA_ARGS__)
 #endif
+
+#ifndef atomic64_dec_return_wrap
+#define  atomic64_dec_return_wrap(...)				\
+	__atomic_op_fence(atomic64_dec_return_wrap, __VA_ARGS__)
+#endif
 #endif /* atomic64_dec_return_relaxed */
 
 
@@ -970,6 +1074,11 @@ static inline int atomic_dec_if_positive(atomic_t *v)
 #define  atomic64_xchg(...)						\
 	__atomic_op_fence(atomic64_xchg, __VA_ARGS__)
 #endif
+
+#ifndef atomic64_xchg_wrap
+#define  atomic64_xchg_wrap(...)				\
+	__atomic_op_fence(atomic64_xchg_wrap, __VA_ARGS__)
+#endif
 #endif /* atomic64_xchg_relaxed */
 
 /* atomic64_cmpxchg_relaxed */
@@ -994,6 +1103,11 @@ static inline int atomic_dec_if_positive(atomic_t *v)
 #define  atomic64_cmpxchg(...)						\
 	__atomic_op_fence(atomic64_cmpxchg, __VA_ARGS__)
 #endif
+
+#ifndef atomic64_cmpxchg_wrap
+#define  atomic64_cmpxchg_wrap(...)					\
+	__atomic_op_fence(atomic64_cmpxchg_wrap, __VA_ARGS__)
+#endif
 #endif /* atomic64_cmpxchg_relaxed */
 
 #ifndef atomic64_andnot
diff --git a/include/linux/types.h b/include/linux/types.h
index baf7183..b47a7f8 100644
--- a/include/linux/types.h
+++ b/include/linux/types.h
@@ -175,10 +175,27 @@ typedef struct {
 	int counter;
 } atomic_t;
 
+#ifdef CONFIG_HARDENED_ATOMIC
+typedef struct {
+	int counter;
+} atomic_wrap_t;
+#else
+typedef atomic_t atomic_wrap_t;
+#endif
+
 #ifdef CONFIG_64BIT
 typedef struct {
 	long counter;
 } atomic64_t;
+
+#ifdef CONFIG_HARDENED_ATOMIC
+typedef struct {
+	long counter;
+} atomic64_wrap_t;
+#else
+typedef atomic64_t atomic64_wrap_t;
+#endif
+
 #endif
 
 struct list_head {
diff --git a/kernel/panic.c b/kernel/panic.c
index e6480e2..cb1d6db 100644
--- a/kernel/panic.c
+++ b/kernel/panic.c
@@ -616,3 +616,14 @@ static int __init oops_setup(char *s)
 	return 0;
 }
 early_param("oops", oops_setup);
+
+#ifdef CONFIG_HARDENED_ATOMIC
+void hardened_atomic_overflow(struct pt_regs *regs)
+{
+	pr_emerg(KERN_EMERG "HARDENED_ATOMIC: overflow detected in: %s:%d, uid/euid: %u/%u\n",
+		current->comm, task_pid_nr(current),
+		from_kuid_munged(&init_user_ns, current_uid()),
+		from_kuid_munged(&init_user_ns, current_euid()));
+	BUG();
+}
+#endif
diff --git a/security/Kconfig b/security/Kconfig
index 118f454..abcf1cc 100644
--- a/security/Kconfig
+++ b/security/Kconfig
@@ -158,6 +158,25 @@ config HARDENED_USERCOPY_PAGESPAN
 	  been removed. This config is intended to be used only while
 	  trying to find such users.
 
+config HAVE_ARCH_HARDENED_ATOMIC
+	bool
+	help
+	  The architecture supports CONFIG_HARDENED_ATOMIC by
+	  providing trapping on atomic_t wraps, with a call to
+	  hardened_atomic_overflow().
+
+config HARDENED_ATOMIC
+	bool "Prevent reference counter overflow in atomic_t"
+	depends on HAVE_ARCH_HARDENED_ATOMIC
+	select BUG
+	help
+	  This option catches counter wrapping in atomic_t, which
+	  can turn refcounting overflow bugs into resource
+	  consumption bugs instead of exploitable use-after-free
+	  flaws. This feature has a negligible
+	  performance impact and therefore recommended to be turned
+	  on for security reasons.
+
 source security/selinux/Kconfig
 source security/smack/Kconfig
 source security/tomoyo/Kconfig
