1 files changed, 30 insertions, 8 deletions

diff --git a/arch/arm64/include/asm/mman.h b/arch/arm64/include/asm/mman.h
index 9e39217b4afb..1d53022fc7e1 100644
--- a/arch/arm64/include/asm/mman.h
+++ b/arch/arm64/include/asm/mman.h
@@ -6,6 +6,8 @@
 
 #ifndef BUILD_VDSO
 #include <linux/compiler.h>
+#include <linux/fs.h>
+#include <linux/shmem_fs.h>
 #include <linux/types.h>
 
 static inline unsigned long arch_calc_vm_prot_bits(unsigned long prot,
@@ -31,19 +33,24 @@ static inline unsigned long arch_calc_vm_prot_bits(unsigned long prot,
 }
 #define arch_calc_vm_prot_bits(prot, pkey) arch_calc_vm_prot_bits(prot, pkey)
 
-static inline unsigned long arch_calc_vm_flag_bits(unsigned long flags)
+static inline unsigned long arch_calc_vm_flag_bits(struct file *file,
+						   unsigned long flags)
 {
 	/*
 	 * Only allow MTE on anonymous mappings as these are guaranteed to be
 	 * backed by tags-capable memory. The vm_flags may be overridden by a
 	 * filesystem supporting MTE (RAM-based).
 	 */
-	if (system_supports_mte() && (flags & MAP_ANONYMOUS))
-		return VM_MTE_ALLOWED;
+	if (system_supports_mte()) {
+		if (flags & (MAP_ANONYMOUS | MAP_HUGETLB))
+			return VM_MTE_ALLOWED;
+		if (shmem_file(file))
+			return VM_MTE_ALLOWED;
+	}
 
 	return 0;
 }
-#define arch_calc_vm_flag_bits(flags) arch_calc_vm_flag_bits(flags)
+#define arch_calc_vm_flag_bits(file, flags) arch_calc_vm_flag_bits(file, flags)
 
 static inline bool arch_validate_prot(unsigned long prot,
 	unsigned long addr __always_unused)
@@ -62,11 +69,26 @@ static inline bool arch_validate_prot(unsigned long prot,
 
 static inline bool arch_validate_flags(unsigned long vm_flags)
 {
-	if (!system_supports_mte())
-		return true;
+	if (system_supports_mte()) {
+		/*
+		 * only allow VM_MTE if VM_MTE_ALLOWED has been set
+		 * previously
+		 */
+		if ((vm_flags & VM_MTE) && !(vm_flags & VM_MTE_ALLOWED))
+			return false;
+	}
+
+	if (system_supports_gcs() && (vm_flags & VM_SHADOW_STACK)) {
+		/* An executable GCS isn't a good idea. */
+		if (vm_flags & VM_EXEC)
+			return false;
+
+		/* The memory management core should prevent this */
+		VM_WARN_ON(vm_flags & VM_SHARED);
+	}
+
+	return true;
 
-	/* only allow VM_MTE if VM_MTE_ALLOWED has been set previously */
-	return !(vm_flags & VM_MTE) || (vm_flags & VM_MTE_ALLOWED);
 }
 #define arch_validate_flags(vm_flags) arch_validate_flags(vm_flags)