2 files changed, 15 insertions, 1 deletions

diff --git a/fs/proc/task_mmu.c b/fs/proc/task_mmu.c
index aea1d3f1ffb5..439fc1f1c1c4 100644
--- a/fs/proc/task_mmu.c
+++ b/fs/proc/task_mmu.c
@@ -210,6 +210,7 @@ static void show_map_vma(struct seq_file *m, struct vm_area_struct *vma)
         int flags = vma->vm_flags;
         unsigned long ino = 0;
         unsigned long long pgoff = 0;
+        unsigned long start;
         dev_t dev = 0;
         int len;
 
@@ -220,8 +221,13 @@ static void show_map_vma(struct seq_file *m, struct vm_area_struct *vma)
                 pgoff = ((loff_t)vma->vm_pgoff) << PAGE_SHIFT;
         }
 
+        /* We don't show the stack guard page in /proc/maps */
+        start = vma->vm_start;
+        if (vma->vm_flags & VM_GROWSDOWN)
+                start += PAGE_SIZE;
+
         seq_printf(m, "%08lx-%08lx %c%c%c%c %08llx %02x:%02x %lu %n",
-                        vma->vm_start,
+                        start,
                         vma->vm_end,
                         flags & VM_READ ? 'r' : '-',
                         flags & VM_WRITE ? 'w' : '-',
diff --git a/mm/mlock.c b/mm/mlock.c
index 3f82720e0515..49e5e4cb8232 100644
--- a/mm/mlock.c
+++ b/mm/mlock.c
@@ -167,6 +167,14 @@ static long __mlock_vma_pages_range(struct vm_area_struct *vma,
         if (vma->vm_flags & VM_WRITE)
                 gup_flags |= FOLL_WRITE;
 
+        /* We don't try to access the guard page of a stack vma */
+        if (vma->vm_flags & VM_GROWSDOWN) {
+                if (start == vma->vm_start) {
+                        start += PAGE_SIZE;
+                        nr_pages--;
+                }
+        }
+
         while (nr_pages > 0) {
                 int i;