[PATCH v6 17/39] kasan, x86, arm64, s390: rename functions for modules shadow

andrey.konovalov
2022-01-24T18:48:32Z

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>
Acked-by: Catalin Marinas <catalin.marinas@arm.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 309a27553c87..d3a1fa818348 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, gfp_mask) < 0)) {
+ if (p && (kasan_alloc_module_shadow(p, size, gfp_mask) < 0)) {
vfree(p);
return NULL;
}
diff --git a/arch/s390/kernel/module.c b/arch/s390/kernel/module.c
index d52d85367bf7..b16bebd9a8b9 100644
--- a/arch/s390/kernel/module.c
+++ b/arch/s390/kernel/module.c
@@ -45,7 +45,7 @@ void *module_alloc(unsigned long size)
p = __vmalloc_node_range(size, MODULE_ALIGN, MODULES_VADDR, MODULES_END,
gfp_mask, PAGE_KERNEL_EXEC, VM_DEFER_KMEMLEAK, NUMA_NO_NODE,
__builtin_return_address(0));
- if (p && (kasan_module_alloc(p, size, gfp_mask) < 0)) {
+ if (p && (kasan_alloc_module_shadow(p, size, gfp_mask) < 0)) {
vfree(p);
return NULL;
}
diff --git a/arch/x86/kernel/module.c b/arch/x86/kernel/module.c
index 95fa745e310a..c9eb8aa3b7b8 100644
--- a/arch/x86/kernel/module.c
+++ b/arch/x86/kernel/module.c
@@ -78,7 +78,7 @@ void *module_alloc(unsigned long size)
MODULES_END, gfp_mask,
PAGE_KERNEL, VM_DEFER_KMEMLEAK, NUMA_NO_NODE,
__builtin_return_address(0));
- if (p && (kasan_module_alloc(p, size, gfp_mask) < 0)) {
+ if (p && (kasan_alloc_module_shadow(p, size, gfp_mask) < 0)) {
vfree(p);
return NULL;
}
diff --git a/include/linux/kasan.h b/include/linux/kasan.h
index b88ca6b97ba3..55f1d4edf6b5 100644
--- a/include/linux/kasan.h
+++ b/include/linux/kasan.h
@@ -454,17 +454,17 @@ 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, gfp_t gfp_mask);
-void kasan_free_shadow(const struct vm_struct *vm);
+int kasan_alloc_module_shadow(void *addr, size_t size, gfp_t gfp_mask);
+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, gfp_t gfp_mask) { 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, gfp_t gfp_mask) { 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 94136f84b449..e5c4393eb861 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, gfp_t gfp_mask)
+int kasan_alloc_module_shadow(void *addr, size_t size, gfp_t gfp_mask)
{
void *ret;
size_t scaled_size;
@@ -534,7 +534,7 @@ int kasan_module_alloc(void *addr, size_t size, gfp_t gfp_mask)
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 4165304d3547..b6712a25c996 100644
--- a/mm/vmalloc.c
+++ b/mm/vmalloc.c
@@ -2526,7 +2526,7 @@ 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;