VMCI: Remove handle_arr_calc_size()

Use struct_size() instead of handle_arr_calc_size().
This is much more conventional.

While at it, use size_add() when computing the needed size in
vmci_handle_arr_append_entry(). This prevents from (unlikely) overflow
when computing the new size to reallocate.

Suggested-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Reviewed-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/84e7f2d8e7c4c2eab68f958307d56546978f76e3.1702125347.git.christophe.jaillet@wanadoo.fr
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Christophe JAILLET 2023-12-09 13:36:14 +01:00 committed by Greg Kroah-Hartman
parent c49739235c
commit bda910d818

View File

@ -8,12 +8,6 @@
#include <linux/slab.h>
#include "vmci_handle_array.h"
static size_t handle_arr_calc_size(u32 capacity)
{
return VMCI_HANDLE_ARRAY_HEADER_SIZE +
capacity * sizeof(struct vmci_handle);
}
struct vmci_handle_arr *vmci_handle_arr_create(u32 capacity, u32 max_capacity)
{
struct vmci_handle_arr *array;
@ -25,7 +19,7 @@ struct vmci_handle_arr *vmci_handle_arr_create(u32 capacity, u32 max_capacity)
capacity = min((u32)VMCI_HANDLE_ARRAY_DEFAULT_CAPACITY,
max_capacity);
array = kmalloc(handle_arr_calc_size(capacity), GFP_ATOMIC);
array = kmalloc(struct_size(array, entries, capacity), GFP_ATOMIC);
if (!array)
return NULL;
@ -51,8 +45,8 @@ int vmci_handle_arr_append_entry(struct vmci_handle_arr **array_ptr,
struct vmci_handle_arr *new_array;
u32 capacity_bump = min(array->max_capacity - array->capacity,
array->capacity);
size_t new_size = handle_arr_calc_size(array->capacity +
capacity_bump);
size_t new_size = struct_size(array, entries,
size_add(array->capacity, capacity_bump));
if (array->size >= array->max_capacity)
return VMCI_ERROR_NO_MEM;