1 files changed, 34 insertions, 21 deletions

diff --git a/mm/vmalloc.c b/mm/vmalloc.c
index a6e7acebe9ad..2d7511654831 100644
--- a/mm/vmalloc.c
+++ b/mm/vmalloc.c
@@ -586,13 +586,13 @@ static int vmap_small_pages_range_noflush(unsigned long addr, unsigned long end,
 			mask |= PGTBL_PGD_MODIFIED;
 		err = vmap_pages_p4d_range(pgd, addr, next, prot, pages, &nr, &mask);
 		if (err)
-			return err;
+			break;
 	} while (pgd++, addr = next, addr != end);
 
 	if (mask & ARCH_PAGE_TABLE_SYNC_MASK)
 		arch_sync_kernel_mappings(start, end);
 
-	return 0;
+	return err;
 }
 
 /*
@@ -1940,7 +1940,7 @@ static inline void setup_vmalloc_vm(struct vm_struct *vm,
 {
 	vm->flags = flags;
 	vm->addr = (void *)va->va_start;
-	vm->size = va_size(va);
+	vm->size = vm->requested_size = va_size(va);
 	vm->caller = caller;
 	va->vm = vm;
 }
@@ -3133,6 +3133,7 @@ struct vm_struct *__get_vm_area_node(unsigned long size,
 
 	area->flags = flags;
 	area->caller = caller;
+	area->requested_size = requested_size;
 
 	va = alloc_vmap_area(size, align, start, end, node, gfp_mask, 0, area);
 	if (IS_ERR(va)) {
@@ -3771,8 +3772,7 @@ void *__vmalloc_node_range_noprof(unsigned long size, unsigned long align,
 	struct vm_struct *area;
 	void *ret;
 	kasan_vmalloc_flags_t kasan_flags = KASAN_VMALLOC_NONE;
-	unsigned long real_size = size;
-	unsigned long real_align = align;
+	unsigned long original_align = align;
 	unsigned int shift = PAGE_SHIFT;
 
 	if (WARN_ON_ONCE(!size))
@@ -3781,7 +3781,7 @@ void *__vmalloc_node_range_noprof(unsigned long size, unsigned long align,
 	if ((size >> PAGE_SHIFT) > totalram_pages()) {
 		warn_alloc(gfp_mask, NULL,
 			"vmalloc error: size %lu, exceeds total pages",
-			real_size);
+			size);
 		return NULL;
 	}
 
@@ -3798,19 +3798,18 @@ void *__vmalloc_node_range_noprof(unsigned long size, unsigned long align,
 		else
 			shift = arch_vmap_pte_supported_shift(size);
 
-		align = max(real_align, 1UL << shift);
-		size = ALIGN(real_size, 1UL << shift);
+		align = max(original_align, 1UL << shift);
 	}
 
 again:
-	area = __get_vm_area_node(real_size, align, shift, VM_ALLOC |
+	area = __get_vm_area_node(size, align, shift, VM_ALLOC |
 				  VM_UNINITIALIZED | vm_flags, start, end, node,
 				  gfp_mask, caller);
 	if (!area) {
 		bool nofail = gfp_mask & __GFP_NOFAIL;
 		warn_alloc(gfp_mask, NULL,
 			"vmalloc error: size %lu, vm_struct allocation failed%s",
-			real_size, (nofail) ? ". Retrying." : "");
+			size, (nofail) ? ". Retrying." : "");
 		if (nofail) {
 			schedule_timeout_uninterruptible(1);
 			goto again;
@@ -3860,7 +3859,7 @@ again:
 	    (gfp_mask & __GFP_SKIP_ZERO))
 		kasan_flags |= KASAN_VMALLOC_INIT;
 	/* KASAN_VMALLOC_PROT_NORMAL already set if required. */
-	area->addr = kasan_unpoison_vmalloc(area->addr, real_size, kasan_flags);
+	area->addr = kasan_unpoison_vmalloc(area->addr, size, kasan_flags);
 
 	/*
 	 * In this function, newly allocated vm_struct has VM_UNINITIALIZED
@@ -3869,17 +3868,15 @@ again:
 	 */
 	clear_vm_uninitialized_flag(area);
 
-	size = PAGE_ALIGN(size);
 	if (!(vm_flags & VM_DEFER_KMEMLEAK))
-		kmemleak_vmalloc(area, size, gfp_mask);
+		kmemleak_vmalloc(area, PAGE_ALIGN(size), gfp_mask);
 
 	return area->addr;
 
 fail:
 	if (shift > PAGE_SHIFT) {
 		shift = PAGE_SHIFT;
-		align = real_align;
-		size = real_size;
+		align = original_align;
 		goto again;
 	}
 
@@ -4067,6 +4064,8 @@ EXPORT_SYMBOL(vzalloc_node_noprof);
  */
 void *vrealloc_noprof(const void *p, size_t size, gfp_t flags)
 {
+	struct vm_struct *vm = NULL;
+	size_t alloced_size = 0;
 	size_t old_size = 0;
 	void *n;
 
@@ -4076,15 +4075,17 @@ void *vrealloc_noprof(const void *p, size_t size, gfp_t flags)
 	}
 
 	if (p) {
-		struct vm_struct *vm;
-
 		vm = find_vm_area(p);
 		if (unlikely(!vm)) {
 			WARN(1, "Trying to vrealloc() nonexistent vm area (%p)\n", p);
 			return NULL;
 		}
 
-		old_size = get_vm_area_size(vm);
+		alloced_size = get_vm_area_size(vm);
+		old_size = vm->requested_size;
+		if (WARN(alloced_size < old_size,
+			 "vrealloc() has mismatched area vs requested sizes (%p)\n", p))
+			return NULL;
 	}
 
 	/*
@@ -4092,14 +4093,26 @@ void *vrealloc_noprof(const void *p, size_t size, gfp_t flags)
 	 * would be a good heuristic for when to shrink the vm_area?
 	 */
 	if (size <= old_size) {
-		/* Zero out spare memory. */
-		if (want_init_on_alloc(flags))
+		/* Zero out "freed" memory. */
+		if (want_init_on_free())
 			memset((void *)p + size, 0, old_size - size);
+		vm->requested_size = size;
 		kasan_poison_vmalloc(p + size, old_size - size);
-		kasan_unpoison_vmalloc(p, size, KASAN_VMALLOC_PROT_NORMAL);
 		return (void *)p;
 	}
 
+	/*
+	 * We already have the bytes available in the allocation; use them.
+	 */
+	if (size <= alloced_size) {
+		kasan_unpoison_vmalloc(p + old_size, size - old_size,
+				       KASAN_VMALLOC_PROT_NORMAL);
+		/* Zero out "alloced" memory. */
+		if (want_init_on_alloc(flags))
+			memset((void *)p + old_size, 0, size - old_size);
+		vm->requested_size = size;
+	}
+
 	/* TODO: Grow the vm_area, i.e. allocate and map additional pages. */
 	n = __vmalloc_noprof(size, flags);
 	if (!n)