From 7ca3027b726be681c8e6292b5a81ebcde7581710 Mon Sep 17 00:00:00 2001 From: Daniel Axtens Date: Thu, 24 Jun 2021 18:39:42 -0700 Subject: [PATCH] mm/vmalloc: unbreak kasan vmalloc support In commit 121e6f3258fe ("mm/vmalloc: hugepage vmalloc mappings"), __vmalloc_node_range was changed such that __get_vm_area_node was no longer called with the requested/real size of the vmalloc allocation, but rather with a rounded-up size. This means that __get_vm_area_node called kasan_unpoision_vmalloc() with a rounded up size rather than the real size. This led to it allowing access to too much memory and so missing vmalloc OOBs and failing the kasan kunit tests. Pass the real size and the desired shift into __get_vm_area_node. This allows it to round up the size for the underlying allocators while still unpoisioning the correct quantity of shadow memory. Adjust the other call-sites to pass in PAGE_SHIFT for the shift value. Link: https://lkml.kernel.org/r/20210617081330.98629-1-dja@axtens.net Link: https://bugzilla.kernel.org/show_bug.cgi?id=213335 Fixes: 121e6f3258fe ("mm/vmalloc: hugepage vmalloc mappings") Signed-off-by: Daniel Axtens Tested-by: David Gow Reviewed-by: Nicholas Piggin Reviewed-by: Uladzislau Rezki (Sony) Tested-by: Andrey Konovalov Acked-by: Andrey Konovalov Cc: Dmitry Vyukov Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- mm/vmalloc.c | 24 ++++++++++++++---------- 1 file changed, 14 insertions(+), 10 deletions(-) diff --git a/mm/vmalloc.c b/mm/vmalloc.c index fada19e..d0a7d89 100644 --- a/mm/vmalloc.c +++ b/mm/vmalloc.c @@ -2344,15 +2344,16 @@ static void clear_vm_uninitialized_flag(struct vm_struct *vm) } static struct vm_struct *__get_vm_area_node(unsigned long size, - unsigned long align, unsigned long flags, unsigned long start, - unsigned long end, int node, gfp_t gfp_mask, const void *caller) + unsigned long align, unsigned long shift, unsigned long flags, + unsigned long start, unsigned long end, int node, + gfp_t gfp_mask, const void *caller) { struct vmap_area *va; struct vm_struct *area; unsigned long requested_size = size; BUG_ON(in_interrupt()); - size = PAGE_ALIGN(size); + size = ALIGN(size, 1ul << shift); if (unlikely(!size)) return NULL; @@ -2384,8 +2385,8 @@ struct vm_struct *__get_vm_area_caller(unsigned long size, unsigned long flags, unsigned long start, unsigned long end, const void *caller) { - return __get_vm_area_node(size, 1, flags, start, end, NUMA_NO_NODE, - GFP_KERNEL, caller); + return __get_vm_area_node(size, 1, PAGE_SHIFT, flags, start, end, + NUMA_NO_NODE, GFP_KERNEL, caller); } /** @@ -2401,7 +2402,8 @@ struct vm_struct *__get_vm_area_caller(unsigned long size, unsigned long flags, */ struct vm_struct *get_vm_area(unsigned long size, unsigned long flags) { - return __get_vm_area_node(size, 1, flags, VMALLOC_START, VMALLOC_END, + return __get_vm_area_node(size, 1, PAGE_SHIFT, flags, + VMALLOC_START, VMALLOC_END, NUMA_NO_NODE, GFP_KERNEL, __builtin_return_address(0)); } @@ -2409,7 +2411,8 @@ struct vm_struct *get_vm_area(unsigned long size, unsigned long flags) struct vm_struct *get_vm_area_caller(unsigned long size, unsigned long flags, const void *caller) { - return __get_vm_area_node(size, 1, flags, VMALLOC_START, VMALLOC_END, + return __get_vm_area_node(size, 1, PAGE_SHIFT, flags, + VMALLOC_START, VMALLOC_END, NUMA_NO_NODE, GFP_KERNEL, caller); } @@ -2902,9 +2905,9 @@ void *__vmalloc_node_range(unsigned long size, unsigned long align, } again: - size = PAGE_ALIGN(size); - area = __get_vm_area_node(size, align, VM_ALLOC | VM_UNINITIALIZED | - vm_flags, start, end, node, gfp_mask, caller); + area = __get_vm_area_node(real_size, align, shift, VM_ALLOC | + VM_UNINITIALIZED | vm_flags, start, end, node, + gfp_mask, caller); if (!area) { warn_alloc(gfp_mask, NULL, "vmalloc size %lu allocation failure: " @@ -2923,6 +2926,7 @@ again: */ clear_vm_uninitialized_flag(area); + size = PAGE_ALIGN(size); kmemleak_vmalloc(area, size, gfp_mask); return addr; -- 2.7.4