Re: [PATCH] i40e: Annotate struct i40e_qvlist_info with __counted_by

From: Gustavo A. R. Silva
Date: Tue Oct 03 2023 - 21:45:25 EST




On 10/4/23 01:18, Kees Cook wrote:
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 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 i40e_qvlist_info.

Cc: Tony Nguyen <anthony.l.nguyen@xxxxxxxxx>
Cc: Shiraz Saleem <shiraz.saleem@xxxxxxxxx>
Cc: Jakub Kicinski <kuba@xxxxxxxxxx>
Cc: Jesse Brandeburg <jesse.brandeburg@xxxxxxxxx>
Cc: Gurucharan G <gurucharanx.g@xxxxxxxxx>
Cc: "Gustavo A. R. Silva" <gustavoars@xxxxxxxxxx>
Link: https://github.com/kees/kernel-tools/blob/trunk/coccinelle/examples/counted_by.cocci [1]
Signed-off-by: Kees Cook <keescook@xxxxxxxxxxxx>

Reviewed-by: Gustavo A. R. Silva <gustavoars@xxxxxxxxxx>

Thanks
--
Gustavo

---
include/linux/net/intel/i40e_client.h | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/include/linux/net/intel/i40e_client.h b/include/linux/net/intel/i40e_client.h
index ed42bd5f639f..0aa4411528fc 100644
--- a/include/linux/net/intel/i40e_client.h
+++ b/include/linux/net/intel/i40e_client.h
@@ -45,7 +45,7 @@ struct i40e_qv_info {
struct i40e_qvlist_info {
u32 num_vectors;
- struct i40e_qv_info qv_info[];
+ struct i40e_qv_info qv_info[] __counted_by(num_vectors);
};