mm: vmalloc: pass proper vm_start into debugobjects

Client can call vunmap with some intermediate 'addr' which may not be
the start of the VM area.  Entire unmap code works with vm->vm_start
which is proper but debug object API is called with 'addr'.  This could
be a problem within debug objects.

Pass proper start address into debug object API.

[[email protected]: fix warning]
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Chintan Pandya <[email protected]>
Reviewed-by: Andrew Morton <[email protected]>
Cc: Ard Biesheuvel <[email protected]>
Cc: Byungchul Park <[email protected]>
Cc: Catalin Marinas <[email protected]>
Cc: Florian Fainelli <[email protected]>
Cc: Johannes Weiner <[email protected]>
Cc: Laura Abbott <[email protected]>
Cc: Vlastimil Babka <[email protected]>
Cc: Wei Yang <[email protected]>
Cc: Yisheng Xie <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>

1 files changed, 5 insertions, 4 deletions

diff --git a/mm/vmalloc.c b/mm/vmalloc.c
index 4df66e1abeb1..89efac3a020e 100644
--- a/mm/vmalloc.c
+++ b/mm/vmalloc.c
@@ -1128,15 +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);
-
 	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);
@@ -1511,8 +1512,8 @@ static void __vunmap(const void *addr, int deallocate_pages)
 		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) {