/proc/pid/smaps: add mseal info for vma

Add sl in /proc/pid/smaps to indicate vma is sealed

Link: https://lkml.kernel.org/r/20240614232014.806352-2-jeffxu@google.com
Fixes: 8be7258 ("mseal: add mseal syscall")
Signed-off-by: Jeff Xu <jeffxu@chromium.org>
Acked-by: David Hildenbrand <david@redhat.com>
Cc: Adhemerval Zanella <adhemerval.zanella@linaro.org>
Cc: Jann Horn <jannh@google.com>
Cc: Jorge Lucangeli Obes <jorgelo@chromium.org>
Cc: Kees Cook <keescook@chromium.org>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: Stephen Röttger <sroettger@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

Author: peaktocreek

Documentation/filesystems/proc.rst

@@ -571,6 +571,7 @@ encoded manner. The codes are the following:
     um    userfaultfd missing tracking
     uw    userfaultfd wr-protect tracking
     ss    shadow stack page
+    sl    sealed
     ==    =======================================
 
 Note that there is no guarantee that every flag and associated mnemonic will

fs/proc/task_mmu.c

@@ -706,6 +706,9 @@ static void show_smap_vma_flags(struct seq_file *m, struct vm_area_struct *vma)
 #endif /* CONFIG_HAVE_ARCH_USERFAULTFD_MINOR */
 #ifdef CONFIG_X86_USER_SHADOW_STACK
 		[ilog2(VM_SHADOW_STACK)] = "ss",
+#endif
+#ifdef CONFIG_64BIT
+		[ilog2(VM_SEALED)] = "sl",
 #endif
 	};
 	size_t i;

include/linux/mm.h

@@ -406,6 +406,11 @@ extern unsigned int kobjsize(const void *objp);
 #define VM_ALLOW_ANY_UNCACHED		VM_NONE
 #endif
 
+#ifdef CONFIG_64BIT
+/* VM is sealed, in vm_flags */
+#define VM_SEALED	_BITUL(63)
+#endif
+
 /* Bits set in the VMA until the stack is in its final location */
 #define VM_STACK_INCOMPLETE_SETUP (VM_RAND_READ | VM_SEQ_READ | VM_STACK_EARLY)
 

mm/internal.h

@@ -1434,11 +1434,6 @@ void __meminit __init_single_page(struct page *page, unsigned long pfn,
 unsigned long shrink_slab(gfp_t gfp_mask, int nid, struct mem_cgroup *memcg,
 			  int priority);
 
-#ifdef CONFIG_64BIT
-/* VM is sealed, in vm_flags */
-#define VM_SEALED	_BITUL(63)
-#endif
-
 #ifdef CONFIG_64BIT
 static inline int can_do_mseal(unsigned long flags)
 {