Merge branch 'akpm/master'

11 files changed, 125 insertions, 78 deletions

diff --git a/Makefile b/Makefile
index 6b8b5dc99a85..f73d71abe990 100644
--- a/Makefile
+++ b/Makefile
@@ -1104,6 +1104,21 @@ ifdef CONFIG_CC_IS_GCC
 KBUILD_CFLAGS += -Wno-maybe-uninitialized
 endif
 
+ifdef CONFIG_CC_IS_GCC
+# The allocators already balk at large sizes, so silence the compiler
+# warnings for bounds checks involving those possible values. While
+# -Wno-alloc-size-larger-than would normally be used here, earlier versions
+# of gcc (<9.1) weirdly don't handle the option correctly when _other_
+# warnings are produced (?!). Using -Walloc-size-larger-than=SIZE_MAX
+# doesn't work (as it is documented to), silently resolving to "0" prior to
+# version 9.1 (and producing an error more recently). Numeric values larger
+# than PTRDIFF_MAX also don't work prior to version 9.1, which are silently
+# ignored, continuing to default to PTRDIFF_MAX. So, left with no other
+# choice, we must perform a versioned check to disable this warning.
+# https://lore.kernel.org/lkml/20210824115859.187f272f@canb.auug.org.au
+KBUILD_CFLAGS += $(call cc-ifversion, -ge, 0901, -Wno-alloc-size-larger-than)
+endif
+
 # disable invalid "can't wrap" optimizations for signed / pointers
 KBUILD_CFLAGS	+= -fno-strict-overflow
 
diff --git a/drivers/of/kexec.c b/drivers/of/kexec.c
index 761fd870d1db..053e241f593c 100644
--- a/drivers/of/kexec.c
+++ b/drivers/of/kexec.c
@@ -16,6 +16,7 @@
 #include <linux/of.h>
 #include <linux/of_fdt.h>
 #include <linux/random.h>
+#include <linux/slab.h>
 #include <linux/types.h>
 
 #define RNG_SEED_SIZE		128
diff --git a/include/linux/compiler_attributes.h b/include/linux/compiler_attributes.h
index 8f2106e9e5c1..8b8b7b090a82 100644
--- a/include/linux/compiler_attributes.h
+++ b/include/linux/compiler_attributes.h
@@ -57,6 +57,12 @@
 #define __aligned_largest               __attribute__((__aligned__))
 
 /*
+ *   gcc: https://gcc.gnu.org/onlinedocs/gcc/Common-Function-Attributes.html#index-alloc_005fsize-function-attribute
+ * clang: https://clang.llvm.org/docs/AttributeReference.html#alloc-size
+ */
+#define __alloc_size(x, ...)		__attribute__((__alloc_size__(x, ## __VA_ARGS__)))
+
+/*
  * Note: users of __always_inline currently do not write "inline" themselves,
  * which seems to be required by gcc to apply the attribute according
  * to its docs (and also "warning: always_inline function might not be
diff --git a/include/linux/gfp.h b/include/linux/gfp.h
index 3745efd21cf6..897538d5ffd2 100644
--- a/include/linux/gfp.h
+++ b/include/linux/gfp.h
@@ -618,8 +618,10 @@ static inline struct folio *folio_alloc(gfp_t gfp, unsigned int order)
 extern unsigned long __get_free_pages(gfp_t gfp_mask, unsigned int order);
 extern unsigned long get_zeroed_page(gfp_t gfp_mask);
 
+__alloc_size(1)
 void *alloc_pages_exact(size_t size, gfp_t gfp_mask);
 void free_pages_exact(void *virt, size_t size);
+__alloc_size(1)
 void * __meminit alloc_pages_exact_nid(int nid, size_t size, gfp_t gfp_mask);
 
 #define __get_free_page(gfp_mask) \
diff --git a/include/linux/mm.h b/include/linux/mm.h
index 40ff114aaf9e..d0b5c5e19c66 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -794,40 +794,6 @@ static inline int is_vmalloc_or_module_addr(const void *x)
 }
 #endif
 
-extern void *kvmalloc_node(size_t size, gfp_t flags, int node);
-static inline void *kvmalloc(size_t size, gfp_t flags)
-{
-	return kvmalloc_node(size, flags, NUMA_NO_NODE);
-}
-static inline void *kvzalloc_node(size_t size, gfp_t flags, int node)
-{
-	return kvmalloc_node(size, flags | __GFP_ZERO, node);
-}
-static inline void *kvzalloc(size_t size, gfp_t flags)
-{
-	return kvmalloc(size, flags | __GFP_ZERO);
-}
-
-static inline void *kvmalloc_array(size_t n, size_t size, gfp_t flags)
-{
-	size_t bytes;
-
-	if (unlikely(check_mul_overflow(n, size, &bytes)))
-		return NULL;
-
-	return kvmalloc(bytes, flags);
-}
-
-static inline void *kvcalloc(size_t n, size_t size, gfp_t flags)
-{
-	return kvmalloc_array(n, size, flags | __GFP_ZERO);
-}
-
-extern void *kvrealloc(const void *p, size_t oldsize, size_t newsize,
-		gfp_t flags);
-extern void kvfree(const void *addr);
-extern void kvfree_sensitive(const void *addr, size_t len);
-
 static inline int head_compound_mapcount(struct page *head)
 {
 	return atomic_read(compound_mapcount_ptr(head)) + 1;
diff --git a/include/linux/percpu.h b/include/linux/percpu.h
index 5e76af742c80..119f41815b32 100644
--- a/include/linux/percpu.h
+++ b/include/linux/percpu.h
@@ -123,6 +123,7 @@ extern int __init pcpu_page_first_chunk(size_t reserved_size,
 				pcpu_fc_populate_pte_fn_t populate_pte_fn);
 #endif
 
+__alloc_size(1)
 extern void __percpu *__alloc_reserved_percpu(size_t size, size_t align);
 extern bool __is_kernel_percpu_address(unsigned long addr, unsigned long *can_addr);
 extern bool is_kernel_percpu_address(unsigned long addr);
@@ -131,7 +132,9 @@ extern bool is_kernel_percpu_address(unsigned long addr);
 extern void __init setup_per_cpu_areas(void);
 #endif
 
+__alloc_size(1)
 extern void __percpu *__alloc_percpu_gfp(size_t size, size_t align, gfp_t gfp);
+__alloc_size(1)
 extern void __percpu *__alloc_percpu(size_t size, size_t align);
 extern void free_percpu(void __percpu *__pdata);
 extern phys_addr_t per_cpu_ptr_to_phys(void *addr);
diff --git a/include/linux/slab.h b/include/linux/slab.h
index 083f3ce550bc..6ce826d8194d 100644
--- a/include/linux/slab.h
+++ b/include/linux/slab.h
@@ -152,8 +152,8 @@ struct kmem_cache *kmem_cache_create_usercopy(const char *name,
 			slab_flags_t flags,
 			unsigned int useroffset, unsigned int usersize,
 			void (*ctor)(void *));
-void kmem_cache_destroy(struct kmem_cache *);
-int kmem_cache_shrink(struct kmem_cache *);
+void kmem_cache_destroy(struct kmem_cache *s);
+int kmem_cache_shrink(struct kmem_cache *s);
 
 /*
  * Please use this macro to create slab caches. Simply specify the
@@ -181,11 +181,12 @@ int kmem_cache_shrink(struct kmem_cache *);
 /*
  * Common kmalloc functions provided by all allocators
  */
-void * __must_check krealloc(const void *, size_t, gfp_t);
-void kfree(const void *);
-void kfree_sensitive(const void *);
-size_t __ksize(const void *);
-size_t ksize(const void *);
+__must_check __alloc_size(2)
+void *krealloc(const void *objp, size_t new_size, gfp_t flags);
+void kfree(const void *objp);
+void kfree_sensitive(const void *objp);
+size_t __ksize(const void *objp);
+size_t ksize(const void *objp);
 #ifdef CONFIG_PRINTK
 bool kmem_valid_obj(void *object);
 void kmem_dump_obj(void *object);
@@ -425,9 +426,10 @@ static __always_inline unsigned int __kmalloc_index(size_t size,
 #define kmalloc_index(s) __kmalloc_index(s, true)
 #endif /* !CONFIG_SLOB */
 
+__alloc_size(1)
 void *__kmalloc(size_t size, gfp_t flags) __assume_kmalloc_alignment __malloc;
-void *kmem_cache_alloc(struct kmem_cache *, gfp_t flags) __assume_slab_alignment __malloc;
-void kmem_cache_free(struct kmem_cache *, void *);
+void *kmem_cache_alloc(struct kmem_cache *s, gfp_t flags) __assume_kmalloc_alignment __malloc;
+void kmem_cache_free(struct kmem_cache *s, void *objp);
 
 /*
  * Bulk allocation and freeing operations. These are accelerated in an
@@ -436,8 +438,8 @@ void kmem_cache_free(struct kmem_cache *, void *);
  *
  * Note that interrupts must be enabled when calling these functions.
  */
-void kmem_cache_free_bulk(struct kmem_cache *, size_t, void **);
-int kmem_cache_alloc_bulk(struct kmem_cache *, gfp_t, size_t, void **);
+void kmem_cache_free_bulk(struct kmem_cache *orig_s, size_t size, void **p);
+int kmem_cache_alloc_bulk(struct kmem_cache *s, gfp_t flags, size_t size, void **p);
 
 /*
  * Caller must not use kfree_bulk() on memory not originally allocated
@@ -449,8 +451,10 @@ static __always_inline void kfree_bulk(size_t size, void **p)
 }
 
 #ifdef CONFIG_NUMA
-void *__kmalloc_node(size_t size, gfp_t flags, int node) __assume_kmalloc_alignment __malloc;
-void *kmem_cache_alloc_node(struct kmem_cache *, gfp_t flags, int node) __assume_slab_alignment __malloc;
+__alloc_size(1)
+void *__kmalloc_node(size_t size, gfp_t flags, int node) __assume_slab_alignment __malloc;
+void *kmem_cache_alloc_node(struct kmem_cache *s, gfp_t flags, int node)
+			    __assume_slab_alignment __malloc;
 #else
 static __always_inline void *__kmalloc_node(size_t size, gfp_t flags, int node)
 {
@@ -464,17 +468,15 @@ static __always_inline void *kmem_cache_alloc_node(struct kmem_cache *s, gfp_t f
 #endif
 
 #ifdef CONFIG_TRACING
-extern void *kmem_cache_alloc_trace(struct kmem_cache *, gfp_t, size_t) __assume_slab_alignment __malloc;
+extern void *kmem_cache_alloc_trace(struct kmem_cache *s, gfp_t flags, size_t size)
+				    __assume_slab_alignment __malloc;
 
 #ifdef CONFIG_NUMA
-extern void *kmem_cache_alloc_node_trace(struct kmem_cache *s,
-					   gfp_t gfpflags,
-					   int node, size_t size) __assume_slab_alignment __malloc;
+extern void *kmem_cache_alloc_node_trace(struct kmem_cache *s, gfp_t gfpflags,
+					 int node, size_t size) __assume_slab_alignment __malloc;
 #else
-static __always_inline void *
-kmem_cache_alloc_node_trace(struct kmem_cache *s,
-			      gfp_t gfpflags,
-			      int node, size_t size)
+static __always_inline void *kmem_cache_alloc_node_trace(struct kmem_cache *s,
+					gfp_t gfpflags, int node, size_t size)
 {
 	return kmem_cache_alloc_trace(s, gfpflags, size);
 }
@@ -490,10 +492,8 @@ static __always_inline void *kmem_cache_alloc_trace(struct kmem_cache *s,
 	return ret;
 }
 
-static __always_inline void *
-kmem_cache_alloc_node_trace(struct kmem_cache *s,
-			      gfp_t gfpflags,
-			      int node, size_t size)
+static __always_inline void *kmem_cache_alloc_node_trace(struct kmem_cache *s,
+					gfp_t gfpflags, int node, size_t size)
 {
 	void *ret = kmem_cache_alloc_node(s, gfpflags, node);
 
@@ -502,13 +502,15 @@ kmem_cache_alloc_node_trace(struct kmem_cache *s,
 }
 #endif /* CONFIG_TRACING */
 
-extern void *kmalloc_order(size_t size, gfp_t flags, unsigned int order) __assume_page_alignment __malloc;
+extern void *kmalloc_order(size_t size, gfp_t flags, unsigned int order)
+			   __assume_page_alignment __malloc;
 
 #ifdef CONFIG_TRACING
-extern void *kmalloc_order_trace(size_t size, gfp_t flags, unsigned int order) __assume_page_alignment __malloc;
+extern void *kmalloc_order_trace(size_t size, gfp_t flags, unsigned int order)
+				 __assume_page_alignment __malloc;
 #else
-static __always_inline void *
-kmalloc_order_trace(size_t size, gfp_t flags, unsigned int order)
+static __always_inline void *kmalloc_order_trace(size_t size, gfp_t flags,
+						 unsigned int order)
 {
 	return kmalloc_order(size, flags, order);
 }
@@ -574,6 +576,7 @@ static __always_inline void *kmalloc_large(size_t size, gfp_t flags)
  *	Try really hard to succeed the allocation but fail
  *	eventually.
  */
+__alloc_size(1)
 static __always_inline void *kmalloc(size_t size, gfp_t flags)
 {
 	if (__builtin_constant_p(size)) {
@@ -596,6 +599,7 @@ static __always_inline void *kmalloc(size_t size, gfp_t flags)
 	return __kmalloc(size, flags);
 }
 
+__alloc_size(1)
 static __always_inline void *kmalloc_node(size_t size, gfp_t flags, int node)
 {
 #ifndef CONFIG_SLOB
@@ -620,6 +624,7 @@ static __always_inline void *kmalloc_node(size_t size, gfp_t flags, int node)
  * @size: element size.
  * @flags: the type of memory to allocate (see kmalloc).
  */
+__alloc_size(1, 2)
 static inline void *kmalloc_array(size_t n, size_t size, gfp_t flags)
 {
 	size_t bytes;
@@ -638,8 +643,9 @@ static inline void *kmalloc_array(size_t n, size_t size, gfp_t flags)
  * @new_size: new size of a single member of the array
  * @flags: the type of memory to allocate (see kmalloc)
  */
-static __must_check inline void *
-krealloc_array(void *p, size_t new_n, size_t new_size, gfp_t flags)
+__must_check __alloc_size(2, 3)
+static inline void *krealloc_array(void *p, size_t new_n, size_t new_size,
+				   gfp_t flags)
 {
 	size_t bytes;
 
@@ -655,6 +661,7 @@ krealloc_array(void *p, size_t new_n, size_t new_size, gfp_t flags)
  * @size: element size.
  * @flags: the type of memory to allocate (see kmalloc).
  */
+__alloc_size(1, 2)
 static inline void *kcalloc(size_t n, size_t size, gfp_t flags)
 {
 	return kmalloc_array(n, size, flags | __GFP_ZERO);
@@ -668,7 +675,7 @@ static inline void *kcalloc(size_t n, size_t size, gfp_t flags)
  * allocator where we care about the real place the memory allocation
  * request comes from.
  */
-extern void *__kmalloc_track_caller(size_t, gfp_t, unsigned long);
+extern void *__kmalloc_track_caller(size_t size, gfp_t flags, unsigned long caller);
 #define kmalloc_track_caller(size, flags) \
 	__kmalloc_track_caller(size, flags, _RET_IP_)
 
@@ -684,6 +691,7 @@ static inline void *kmalloc_array_node(size_t n, size_t size, gfp_t flags,
 	return __kmalloc_node(bytes, flags, node);
 }
 
+__alloc_size(1, 2)
 static inline void *kcalloc_node(size_t n, size_t size, gfp_t flags, int node)
 {
 	return kmalloc_array_node(n, size, flags | __GFP_ZERO, node);
@@ -691,7 +699,8 @@ static inline void *kcalloc_node(size_t n, size_t size, gfp_t flags, int node)
 
 
 #ifdef CONFIG_NUMA
-extern void *__kmalloc_node_track_caller(size_t, gfp_t, int, unsigned long);
+extern void *__kmalloc_node_track_caller(size_t size, gfp_t flags, int node,
+					 unsigned long caller);
 #define kmalloc_node_track_caller(size, flags, node) \
 	__kmalloc_node_track_caller(size, flags, node, \
 			_RET_IP_)
@@ -716,6 +725,7 @@ static inline void *kmem_cache_zalloc(struct kmem_cache *k, gfp_t flags)
  * @size: how many bytes of memory are required.
  * @flags: the type of memory to allocate (see kmalloc).
  */
+__alloc_size(1)
 static inline void *kzalloc(size_t size, gfp_t flags)
 {
 	return kmalloc(size, flags | __GFP_ZERO);
@@ -727,11 +737,53 @@ static inline void *kzalloc(size_t size, gfp_t flags)
  * @flags: the type of memory to allocate (see kmalloc).
  * @node: memory node from which to allocate
  */
+__alloc_size(1)
 static inline void *kzalloc_node(size_t size, gfp_t flags, int node)
 {
 	return kmalloc_node(size, flags | __GFP_ZERO, node);
 }
 
+__alloc_size(1)
+extern void *kvmalloc_node(size_t size, gfp_t flags, int node);
+__alloc_size(1)
+static inline void *kvmalloc(size_t size, gfp_t flags)
+{
+	return kvmalloc_node(size, flags, NUMA_NO_NODE);
+}
+__alloc_size(1)
+static inline void *kvzalloc_node(size_t size, gfp_t flags, int node)
+{
+	return kvmalloc_node(size, flags | __GFP_ZERO, node);
+}
+__alloc_size(1)
+static inline void *kvzalloc(size_t size, gfp_t flags)
+{
+	return kvmalloc(size, flags | __GFP_ZERO);
+}
+
+__alloc_size(1, 2)
+static inline void *kvmalloc_array(size_t n, size_t size, gfp_t flags)
+{
+	size_t bytes;
+
+	if (unlikely(check_mul_overflow(n, size, &bytes)))
+		return NULL;
+
+	return kvmalloc(bytes, flags);
+}
+
+__alloc_size(1, 2)
+static inline void *kvcalloc(size_t n, size_t size, gfp_t flags)
+{
+	return kvmalloc_array(n, size, flags | __GFP_ZERO);
+}
+
+__alloc_size(3)
+extern void *kvrealloc(const void *p, size_t oldsize, size_t newsize,
+		gfp_t flags);
+extern void kvfree(const void *addr);
+extern void kvfree_sensitive(const void *addr, size_t len);
+
 unsigned int kmem_cache_size(struct kmem_cache *s);
 void __init kmem_cache_init_late(void);
 
diff --git a/include/linux/vmalloc.h b/include/linux/vmalloc.h
index 671d402c3778..d1008bb0f569 100644
--- a/include/linux/vmalloc.h
+++ b/include/linux/vmalloc.h
@@ -136,20 +136,31 @@ static inline void vmalloc_init(void)
 static inline unsigned long vmalloc_nr_pages(void) { return 0; }
 #endif
 
+__alloc_size(1)
 extern void *vmalloc(unsigned long size);
+__alloc_size(1)
 extern void *vzalloc(unsigned long size);
+__alloc_size(1)
 extern void *vmalloc_user(unsigned long size);
+__alloc_size(1)
 extern void *vmalloc_node(unsigned long size, int node);
+__alloc_size(1)
 extern void *vzalloc_node(unsigned long size, int node);
+__alloc_size(1)
 extern void *vmalloc_32(unsigned long size);
+__alloc_size(1)
 extern void *vmalloc_32_user(unsigned long size);
+__alloc_size(1)
 extern void *__vmalloc(unsigned long size, gfp_t gfp_mask);
+__alloc_size(1)
 extern void *__vmalloc_node_range(unsigned long size, unsigned long align,
 			unsigned long start, unsigned long end, gfp_t gfp_mask,
 			pgprot_t prot, unsigned long vm_flags, int node,
 			const void *caller);
+__alloc_size(1)
 void *__vmalloc_node(unsigned long size, unsigned long align, gfp_t gfp_mask,
 		int node, const void *caller);
+__alloc_size(1)
 void *vmalloc_no_huge(unsigned long size);
 
 extern void vfree(const void *addr);
diff --git a/mm/memcontrol.c b/mm/memcontrol.c
index 03e82d74b645..a73689caee5d 100644
--- a/mm/memcontrol.c
+++ b/mm/memcontrol.c
@@ -2014,13 +2014,11 @@ again:
 	memcg->move_lock_task = current;
 	memcg->move_lock_flags = flags;
 }
-EXPORT_SYMBOL(folio_memcg_lock);
 
 void lock_page_memcg(struct page *page)
 {
 	folio_memcg_lock(page_folio(page));
 }
-EXPORT_SYMBOL(lock_page_memcg);
 
 static void __folio_memcg_unlock(struct mem_cgroup *memcg)
 {
@@ -2048,13 +2046,11 @@ void folio_memcg_unlock(struct folio *folio)
 {
 	__folio_memcg_unlock(folio_memcg(folio));
 }
-EXPORT_SYMBOL(folio_memcg_unlock);
 
 void unlock_page_memcg(struct page *page)
 {
 	folio_memcg_unlock(page_folio(page));
 }
-EXPORT_SYMBOL(unlock_page_memcg);
 
 struct obj_stock {
 #ifdef CONFIG_MEMCG_KMEM
diff --git a/mm/migrate.c b/mm/migrate.c
index 433c453b47f9..04a76fc21912 100644
--- a/mm/migrate.c
+++ b/mm/migrate.c
@@ -404,12 +404,6 @@ int folio_migrate_mapping(struct address_space *mapping,
 	newzone = folio_zone(newfolio);
 
 	xas_lock_irq(&xas);
-	if (folio_ref_count(folio) != expected_count ||
-	    xas_load(&xas) != folio) {
-		xas_unlock_irq(&xas);
-		return -EAGAIN;
-	}
-
 	if (!folio_ref_freeze(folio, expected_count)) {
 		xas_unlock_irq(&xas);
 		return -EAGAIN;
diff --git a/scripts/checkpatch.pl b/scripts/checkpatch.pl
index c27d2312cfc3..88cb294dc447 100755
--- a/scripts/checkpatch.pl
+++ b/scripts/checkpatch.pl
@@ -489,7 +489,8 @@ our $Attribute	= qr{
 			____cacheline_aligned|
 			____cacheline_aligned_in_smp|
 			____cacheline_internodealigned_in_smp|
-			__weak
+			__weak|
+			__alloc_size\s*\(\s*\d+\s*(?:,\s*\d+\s*)?\)
 		  }x;
 our $Modifier;
 our $Inline	= qr{inline|__always_inline|noinline|__inline|__inline__};