Re: [PATCH] net/i40e: Replace 0-length array with flexible array

[Jiri Pirko]

Fri, Jan 06, 2023 at 12:46:01AM CET, keescook@xxxxxxxxxxxx wrote:
>Zero-length arrays are deprecated[1]. Replace struct i40e_lump_tracking's
>"list" 0-length array with a flexible array. Detected with GCC 13,
>using -fstrict-flex-arrays=3:
>
>In function 'i40e_put_lump',
>    inlined from 'i40e_clear_interrupt_scheme' at drivers/net/ethernet/intel/i40e/i40e_main.c:5145:2:
>drivers/net/ethernet/intel/i40e/i40e_main.c:278:27: warning: array subscript <unknown> is outside array bounds of 'u16[0]' {aka 'short unsigned int[]'} [-Warray-bounds=]
>  278 |                 pile->list[i] = 0;
>      |                 ~~~~~~~~~~^~~
>drivers/net/ethernet/intel/i40e/i40e.h: In function 'i40e_clear_interrupt_scheme':
>drivers/net/ethernet/intel/i40e/i40e.h:179:13: note: while referencing 'list'
>  179 |         u16 list[0];
>      |             ^~~~
>
>[1] https://www.kernel.org/doc/html/latest/process/deprecated.html#zero-length-and-one-element-arrays
>
>Cc: Jesse Brandeburg <jesse.brandeburg@xxxxxxxxx>
>Cc: Tony Nguyen <anthony.l.nguyen@xxxxxxxxx>
>Cc: "David S. Miller" <davem@xxxxxxxxxxxxx>
>Cc: Eric Dumazet <edumazet@xxxxxxxxxx>
>Cc: Jakub Kicinski <kuba@xxxxxxxxxx>
>Cc: Paolo Abeni <pabeni@xxxxxxxxxx>
>Cc: "Gustavo A. R. Silva" <gustavoars@xxxxxxxxxx>
>Cc: intel-wired-lan@xxxxxxxxxxxxxxxx
>Cc: netdev@xxxxxxxxxxxxxxx
>Signed-off-by: Kees Cook <keescook@xxxxxxxxxxxx>

Reviewed-by: Jiri Pirko <jiri@xxxxxxxxxx>