1 files changed, 62 insertions, 12 deletions

diff --git a/mm/execmem.c b/mm/execmem.c
index 80e61c1e7319..0c4b36bc6d10 100644
--- a/mm/execmem.c
+++ b/mm/execmem.c
@@ -12,27 +12,49 @@
 #include <linux/moduleloader.h>
 
 static struct execmem_info *execmem_info __ro_after_init;
+static struct execmem_info default_execmem_info __ro_after_init;
 
 static void *__execmem_alloc(struct execmem_range *range, size_t size)
 {
+	bool kasan = range->flags & EXECMEM_KASAN_SHADOW;
+	unsigned long vm_flags  = VM_FLUSH_RESET_PERMS;
+	gfp_t gfp_flags = GFP_KERNEL | __GFP_NOWARN;
 	unsigned long start = range->start;
 	unsigned long end = range->end;
 	unsigned int align = range->alignment;
 	pgprot_t pgprot = range->pgprot;
+	void *p;
+
+	if (kasan)
+		vm_flags |= VM_DEFER_KMEMLEAK;
+
+	p = __vmalloc_node_range(size, align, start, end, gfp_flags,
+				 pgprot, vm_flags, NUMA_NO_NODE,
+				 __builtin_return_address(0));
+	if (!p && range->fallback_start) {
+		start = range->fallback_start;
+		end = range->fallback_end;
+		p = __vmalloc_node_range(size, align, start, end, gfp_flags,
+					 pgprot, vm_flags, NUMA_NO_NODE,
+					 __builtin_return_address(0));
+	}
+
+	if (!p) {
+		pr_warn_ratelimited("execmem: unable to allocate memory\n");
+		return NULL;
+	}
+
+	if (kasan && (kasan_alloc_module_shadow(p, size, GFP_KERNEL) < 0)) {
+		vfree(p);
+		return NULL;
+	}
 
-	return __vmalloc_node_range(size, align, start, end,
-				    GFP_KERNEL, pgprot, VM_FLUSH_RESET_PERMS,
-				    NUMA_NO_NODE, __builtin_return_address(0));
+	return kasan_reset_tag(p);
 }
 
 void *execmem_alloc(enum execmem_type type, size_t size)
 {
-	struct execmem_range *range;
-
-	if (!execmem_info)
-		return module_alloc(size);
-
-	range = &execmem_info->ranges[type];
+	struct execmem_range *range = &execmem_info->ranges[type];
 
 	return __execmem_alloc(range, size);
 }
@@ -67,10 +89,16 @@ static void execmem_init_missing(struct execmem_info *info)
 		struct execmem_range *r = &info->ranges[i];
 
 		if (!r->start) {
-			r->pgprot = default_range->pgprot;
+			if (i == EXECMEM_MODULE_DATA)
+				r->pgprot = PAGE_KERNEL;
+			else
+				r->pgprot = default_range->pgprot;
 			r->alignment = default_range->alignment;
 			r->start = default_range->start;
 			r->end = default_range->end;
+			r->flags = default_range->flags;
+			r->fallback_start = default_range->fallback_start;
+			r->fallback_end = default_range->fallback_end;
 		}
 	}
 }
@@ -80,14 +108,36 @@ struct execmem_info * __weak execmem_arch_setup(void)
 	return NULL;
 }
 
-void __init execmem_init(void)
+static void __init __execmem_init(void)
 {
 	struct execmem_info *info = execmem_arch_setup();
 
-	if (!info || !execmem_validate(info))
+	if (!info) {
+		info = execmem_info = &default_execmem_info;
+		info->ranges[EXECMEM_DEFAULT].start = VMALLOC_START;
+		info->ranges[EXECMEM_DEFAULT].end = VMALLOC_END;
+		info->ranges[EXECMEM_DEFAULT].pgprot = PAGE_KERNEL_EXEC;
+		info->ranges[EXECMEM_DEFAULT].alignment = 1;
+	}
+
+	if (!execmem_validate(info))
 		return;
 
 	execmem_init_missing(info);
 
 	execmem_info = info;
 }
+
+#ifdef CONFIG_ARCH_WANTS_EXECMEM_LATE
+static int __init execmem_late_init(void)
+{
+	__execmem_init();
+	return 0;
+}
+core_initcall(execmem_late_init);
+#else
+void __init execmem_init(void)
+{
+	__execmem_init();
+}
+#endif