From:   andrey.konovalov@linux.dev
To:     Marco Elver <elver@google.com>,
        Alexander Potapenko <glider@google.com>,
        Vincenzo Frascino <vincenzo.frascino@arm.com>,
        Catalin Marinas <catalin.marinas@arm.com>,
        Peter Collingbourne <pcc@google.com>
Cc:     Andrey Konovalov <andreyknvl@gmail.com>,
        Dmitry Vyukov <dvyukov@google.com>,
        Andrey Ryabinin <ryabinin.a.a@gmail.com>,
        kasan-dev@googlegroups.com,
        Andrew Morton <akpm@linux-foundation.org>, linux-mm@kvack.org,
        Will Deacon <will@kernel.org>,
        Mark Rutland <mark.rutland@arm.com>,
        linux-arm-kernel@lists.infradead.org,
        Evgenii Stepanov <eugenis@google.com>,
        linux-kernel@vger.kernel.org,
        Andrey Konovalov <andreyknvl@google.com>
Subject: [PATCH v2 17/34] kasan, x86, arm64, s390: rename functions for modules shadow
Date:   Mon,  6 Dec 2021 22:43:54 +0100
Message-Id: <11f5a6419f8830fdedc84dca5f847543ef7960f4.1638825394.git.andreyknvl@google.com>
In-Reply-To: <cover.1638825394.git.andreyknvl@google.com>
References: <cover.1638825394.git.andreyknvl@google.com>
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From: Andrey Konovalov <andreyknvl@google.com>

Rename kasan_free_shadow to kasan_free_module_shadow and
kasan_module_alloc to kasan_alloc_module_shadow.

These functions are used to allocate/free shadow memory for kernel
modules when KASAN_VMALLOC is not enabled. The new names better
reflect their purpose.

Also reword the comment next to their declaration to improve clarity.

Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
---
 arch/arm64/kernel/module.c |  2 +-
 arch/s390/kernel/module.c  |  2 +-
 arch/x86/kernel/module.c   |  2 +-
 include/linux/kasan.h      | 14 +++++++-------
 mm/kasan/shadow.c          |  4 ++--
 mm/vmalloc.c               |  2 +-
 6 files changed, 13 insertions(+), 13 deletions(-)

diff --git a/arch/arm64/kernel/module.c b/arch/arm64/kernel/module.c
index b5ec010c481f..f8bd5100efb5 100644
--- a/arch/arm64/kernel/module.c
+++ b/arch/arm64/kernel/module.c
@@ -58,7 +58,7 @@ void *module_alloc(unsigned long size)
 				PAGE_KERNEL, 0, NUMA_NO_NODE,
 				__builtin_return_address(0));
 
-	if (p && (kasan_module_alloc(p, size) < 0)) {
+	if (p && (kasan_alloc_module_shadow(p, size) < 0)) {
 		vfree(p);
 		return NULL;
 	}
diff --git a/arch/s390/kernel/module.c b/arch/s390/kernel/module.c
index b01ba460b7ca..a753cebedda9 100644
--- a/arch/s390/kernel/module.c
+++ b/arch/s390/kernel/module.c
@@ -44,7 +44,7 @@ void *module_alloc(unsigned long size)
 	p = __vmalloc_node_range(size, MODULE_ALIGN, MODULES_VADDR, MODULES_END,
 				 GFP_KERNEL, PAGE_KERNEL_EXEC, 0, NUMA_NO_NODE,
 				 __builtin_return_address(0));
-	if (p && (kasan_module_alloc(p, size) < 0)) {
+	if (p && (kasan_alloc_module_shadow(p, size) < 0)) {
 		vfree(p);
 		return NULL;
 	}
diff --git a/arch/x86/kernel/module.c b/arch/x86/kernel/module.c
index 169fb6f4cd2e..dec41d9ba337 100644
--- a/arch/x86/kernel/module.c
+++ b/arch/x86/kernel/module.c
@@ -77,7 +77,7 @@ void *module_alloc(unsigned long size)
 				    MODULES_END, GFP_KERNEL,
 				    PAGE_KERNEL, 0, NUMA_NO_NODE,
 				    __builtin_return_address(0));
-	if (p && (kasan_module_alloc(p, size) < 0)) {
+	if (p && (kasan_alloc_module_shadow(p, size) < 0)) {
 		vfree(p);
 		return NULL;
 	}
diff --git a/include/linux/kasan.h b/include/linux/kasan.h
index 1031070be3f3..4eec58e6ef82 100644
--- a/include/linux/kasan.h
+++ b/include/linux/kasan.h
@@ -453,17 +453,17 @@ static inline void kasan_populate_early_vm_area_shadow(void *start,
 		!defined(CONFIG_KASAN_VMALLOC)
 
 /*
- * These functions provide a special case to support backing module
- * allocations with real shadow memory. With KASAN vmalloc, the special
- * case is unnecessary, as the work is handled in the generic case.
+ * These functions allocate and free shadow memory for kernel modules.
+ * They are only required when KASAN_VMALLOC is not supported, as otherwise
+ * shadow memory is allocated by the generic vmalloc handlers.
  */
-int kasan_module_alloc(void *addr, size_t size);
-void kasan_free_shadow(const struct vm_struct *vm);
+int kasan_alloc_module_shadow(void *addr, size_t size);
+void kasan_free_module_shadow(const struct vm_struct *vm);
 
 #else /* (CONFIG_KASAN_GENERIC || CONFIG_KASAN_SW_TAGS) && !CONFIG_KASAN_VMALLOC */
 
-static inline int kasan_module_alloc(void *addr, size_t size) { return 0; }
-static inline void kasan_free_shadow(const struct vm_struct *vm) {}
+static inline int kasan_alloc_module_shadow(void *addr, size_t size) { return 0; }
+static inline void kasan_free_module_shadow(const struct vm_struct *vm) {}
 
 #endif /* (CONFIG_KASAN_GENERIC || CONFIG_KASAN_SW_TAGS) && !CONFIG_KASAN_VMALLOC */
 
diff --git a/mm/kasan/shadow.c b/mm/kasan/shadow.c
index 4a4929b29a23..585c2bf1073b 100644
--- a/mm/kasan/shadow.c
+++ b/mm/kasan/shadow.c
@@ -498,7 +498,7 @@ void kasan_release_vmalloc(unsigned long start, unsigned long end,
 
 #else /* CONFIG_KASAN_VMALLOC */
 
-int kasan_module_alloc(void *addr, size_t size)
+int kasan_alloc_module_shadow(void *addr, size_t size)
 {
 	void *ret;
 	size_t scaled_size;
@@ -529,7 +529,7 @@ int kasan_module_alloc(void *addr, size_t size)
 	return -ENOMEM;
 }
 
-void kasan_free_shadow(const struct vm_struct *vm)
+void kasan_free_module_shadow(const struct vm_struct *vm)
 {
 	if (vm->flags & VM_KASAN)
 		vfree(kasan_mem_to_shadow(vm->addr));
diff --git a/mm/vmalloc.c b/mm/vmalloc.c
index d2a00ad4e1dd..c5235e3e5857 100644
--- a/mm/vmalloc.c
+++ b/mm/vmalloc.c
@@ -2524,7 +2524,7 @@ struct vm_struct *remove_vm_area(const void *addr)
 		va->vm = NULL;
 		spin_unlock(&vmap_area_lock);
 
-		kasan_free_shadow(vm);
+		kasan_free_module_shadow(vm);
 		free_unmap_vmap_area(va);
 
 		return vm;
-- 
2.25.1