Re: [v3] iwlwifi: pcie: fix constant-conversion warning

From: Kalle Valo
Date: Mon Nov 22 2021 - 13:35:43 EST


Arnd Bergmann <arnd@xxxxxxxxxx> wrote:

> From: Arnd Bergmann <arnd@xxxxxxxx>
>
> Both gcc-11 and clang point out a potential issue with integer overflow when
> the iwl_dev_info_table[] array is empty. This is what clang warns:
>
> drivers/net/wireless/intel/iwlwifi/pcie/drv.c:1344:42: error: implicit conversion from 'unsigned long' to 'int' changes value from 18446744073709551615 to -1 [-Werror,-Wconstant-conversion]
> for (i = ARRAY_SIZE(iwl_dev_info_table) - 1; i >= 0; i--) {
> ~ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~^~~
>
> This is still harmless, as the loop correctly terminates, but adding
> an extra range check makes that obvious to both readers and to the
> compiler.
>
> Fixes: 3f7320428fa4 ("iwlwifi: pcie: simplify iwl_pci_find_dev_info()")
> Reported-by: kernel test robot <lkp@xxxxxxxxx>
> Cc: Nick Desaulniers <ndesaulniers@xxxxxxxxxx>
> Signed-off-by: Arnd Bergmann <arnd@xxxxxxxx>
> Reviewed-by: Nathan Chancellor <nathan@xxxxxxxxxx>

Patch applied to wireless-drivers.git, thanks.

fe785f56ad58 iwlwifi: pcie: fix constant-conversion warning

--
https://patchwork.kernel.org/project/linux-wireless/patch/20211118142124.526901-1-arnd@xxxxxxxxxx/

https://wireless.wiki.kernel.org/en/developers/documentation/submittingpatches