Re: [PATCH v3] igb: Fix string truncation warnings in igb_set_fw_version

From: Simon Horman
Date: Fri Jan 19 2024 - 09:57:27 EST


On Mon, Jan 15, 2024 at 04:28:25PM +0800, Kunwu Chan wrote:
> Commit 1978d3ead82c ("intel: fix string truncation warnings")
> fixes '-Wformat-truncation=' warnings in igb_main.c by using kasprintf.
>
> drivers/net/ethernet/intel/igb/igb_main.c:3092:53: warning:‘%d’ directive output may be truncated writing between 1 and 5 bytes into a region of size between 1 and 13 [-Wformat-truncation=]
> 3092 | "%d.%d, 0x%08x, %d.%d.%d",
> | ^~
> drivers/net/ethernet/intel/igb/igb_main.c:3092:34: note:directive argument in the range [0, 65535]
> 3092 | "%d.%d, 0x%08x, %d.%d.%d",
> | ^~~~~~~~~~~~~~~~~~~~~~~~~
> drivers/net/ethernet/intel/igb/igb_main.c:3092:34: note:directive argument in the range [0, 65535]
> drivers/net/ethernet/intel/igb/igb_main.c:3090:25: note:‘snprintf’ output between 23 and 43 bytes into a destination of size 32
>
> kasprintf() returns a pointer to dynamically allocated memory
> which can be NULL upon failure.
>
> Fix this warning by using a larger space for adapter->fw_version,
> and then fall back and continue to use snprintf.
>
> Fixes: 1978d3ead82c ("intel: fix string truncation warnings")
> Signed-off-by: Kunwu Chan <chentao@xxxxxxxxxx>
> Cc: Kunwu Chan <kunwu.chan@xxxxxxxxxxx>
> Suggested-by: Jakub Kicinski <kuba@xxxxxxxxxx>

Reviewed-by: Simon Horman <horms@xxxxxxxxxx>