1 files changed, 19 insertions, 43 deletions

diff --git a/mm/vmalloc.c b/mm/vmalloc.c
index ebff729cc956..cfea25be7754 100644
--- a/mm/vmalloc.c
+++ b/mm/vmalloc.c
@@ -603,26 +603,6 @@ static void unmap_vmap_area(struct vmap_area *va)
 	vunmap_page_range(va->va_start, va->va_end);
 }
 
-static void vmap_debug_free_range(unsigned long start, unsigned long end)
-{
-	/*
-	 * Unmap page tables and force a TLB flush immediately if pagealloc
-	 * debugging is enabled.  This catches use after free bugs similarly to
-	 * those in linear kernel virtual address space after a page has been
-	 * freed.
-	 *
-	 * All the lazy freeing logic is still retained, in order to minimise
-	 * intrusiveness of this debugging feature.
-	 *
-	 * This is going to be *slow* (linear kernel virtual address debugging
-	 * doesn't do a broadcast TLB flush so it is a lot faster).
-	 */
-	if (debug_pagealloc_enabled()) {
-		vunmap_page_range(start, end);
-		flush_tlb_kernel_range(start, end);
-	}
-}
-
 /*
  * lazy_max_pages is the maximum amount of virtual address space we gather up
  * before attempting to purge with a TLB flush.
@@ -756,6 +736,9 @@ static void free_unmap_vmap_area(struct vmap_area *va)
 {
 	flush_cache_vunmap(va->va_start, va->va_end);
 	unmap_vmap_area(va);
+	if (debug_pagealloc_enabled())
+		flush_tlb_kernel_range(va->va_start, va->va_end);
+
 	free_vmap_area_noflush(va);
 }
 
@@ -1053,6 +1036,10 @@ static void vb_free(const void *addr, unsigned long size)
 
 	vunmap_page_range((unsigned long)addr, (unsigned long)addr + size);
 
+	if (debug_pagealloc_enabled())
+		flush_tlb_kernel_range((unsigned long)addr,
+					(unsigned long)addr + size);
+
 	spin_lock(&vb->lock);
 
 	/* Expand dirty range */
@@ -1141,16 +1128,16 @@ void vm_unmap_ram(const void *mem, unsigned int count)
 	BUG_ON(addr > VMALLOC_END);
 	BUG_ON(!PAGE_ALIGNED(addr));
 
-	debug_check_no_locks_freed(mem, size);
-	vmap_debug_free_range(addr, addr+size);
-
 	if (likely(count <= VMAP_MAX_ALLOC)) {
+		debug_check_no_locks_freed(mem, size);
 		vb_free(mem, size);
 		return;
 	}
 
 	va = find_vmap_area(addr);
 	BUG_ON(!va);
+	debug_check_no_locks_freed((void *)va->va_start,
+				    (va->va_end - va->va_start));
 	free_unmap_vmap_area(va);
 }
 EXPORT_SYMBOL(vm_unmap_ram);
@@ -1499,7 +1486,6 @@ struct vm_struct *remove_vm_area(const void *addr)
 		va->flags |= VM_LAZY_FREE;
 		spin_unlock(&vmap_area_lock);
 
-		vmap_debug_free_range(va->va_start, va->va_end);
 		kasan_free_shadow(vm);
 		free_unmap_vmap_area(va);
 
@@ -1519,16 +1505,17 @@ static void __vunmap(const void *addr, int deallocate_pages)
 			addr))
 		return;
 
-	area = remove_vm_area(addr);
+	area = find_vmap_area((unsigned long)addr)->vm;
 	if (unlikely(!area)) {
 		WARN(1, KERN_ERR "Trying to vfree() nonexistent vm area (%p)\n",
 				addr);
 		return;
 	}
 
-	debug_check_no_locks_freed(addr, get_vm_area_size(area));
-	debug_check_no_obj_freed(addr, get_vm_area_size(area));
+	debug_check_no_locks_freed(area->addr, get_vm_area_size(area));
+	debug_check_no_obj_freed(area->addr, get_vm_area_size(area));
 
+	remove_vm_area(addr);
 	if (deallocate_pages) {
 		int i;
 
@@ -2751,25 +2738,14 @@ static const struct seq_operations vmalloc_op = {
 	.show = s_show,
 };
 
-static int vmalloc_open(struct inode *inode, struct file *file)
+static int __init proc_vmalloc_init(void)
 {
 	if (IS_ENABLED(CONFIG_NUMA))
-		return seq_open_private(file, &vmalloc_op,
-					nr_node_ids * sizeof(unsigned int));
+		proc_create_seq_private("vmallocinfo", 0400, NULL,
+				&vmalloc_op,
+				nr_node_ids * sizeof(unsigned int), NULL);
 	else
-		return seq_open(file, &vmalloc_op);
-}
-
-static const struct file_operations proc_vmalloc_operations = {
-	.open		= vmalloc_open,
-	.read		= seq_read,
-	.llseek		= seq_lseek,
-	.release	= seq_release_private,
-};
-
-static int __init proc_vmalloc_init(void)
-{
-	proc_create("vmallocinfo", S_IRUSR, NULL, &proc_vmalloc_operations);
+		proc_create_seq("vmallocinfo", 0400, NULL, &vmalloc_op);
 	return 0;
 }
 module_init(proc_vmalloc_init);