virt: acrn: Annotate struct vm_memory_region_batch with __counted_by

Prepare for the coming implementation by GCC and Clang of the __counted_by
attribute. Flexible array members annotated with __counted_by can have
their accesses bounds-checked at run-time checking via CONFIG_UBSAN_BOUNDS
(for array indexing) and CONFIG_FORTIFY_SOURCE (for strcpy/memcpy-family
functions).

As found with Coccinelle[1], add __counted_by for struct vm_memory_region_batch.
Additionally, since the element count member must be set before accessing
the annotated flexible array member, move its initialization earlier.

[1] https://github.com/kees/kernel-tools/blob/trunk/coccinelle/examples/counted_by.cocci

Cc: Fei Li <fei1.li@intel.com>
Reviewed-by: "Gustavo A. R. Silva" <gustavoars@kernel.org>
Link: https://lore.kernel.org/r/20230922175102.work.020-kees@kernel.org
Signed-off-by: Kees Cook <keescook@chromium.org>
This commit is contained in:
Kees Cook 2023-09-22 10:51:02 -07:00
parent 4a530cb932
commit 51a71ab21f
2 changed files with 2 additions and 2 deletions

View File

@ -60,7 +60,7 @@ struct vm_memory_region_batch {
u16 reserved[3];
u32 regions_num;
u64 regions_gpa;
struct vm_memory_region_op regions_op[];
struct vm_memory_region_op regions_op[] __counted_by(regions_num);
};
/**

View File

@ -250,11 +250,11 @@ int acrn_vm_ram_map(struct acrn_vm *vm, struct acrn_vm_memmap *memmap)
ret = -ENOMEM;
goto unmap_kernel_map;
}
regions_info->regions_num = nr_regions;
/* Fill each vm_memory_region_op */
vm_region = regions_info->regions_op;
regions_info->vmid = vm->vmid;
regions_info->regions_num = nr_regions;
regions_info->regions_gpa = virt_to_phys(vm_region);
user_vm_pa = memmap->user_vm_pa;
i = 0;