On Thu, Mar 27, 2025 at 11:12:11AM -0600, Gustavo A. R. Silva wrote: > -Wflex-array-member-not-at-end was introduced in GCC-14, and we are > getting ready to enable it, globally. > > Use the `DEFINE_RAW_FLEX()` helper for on-stack definitions of > a flexible structure where the size of the flexible-array member > is known at compile-time, and refactor the rest of the code, > accordingly. > > So, with these changes, fix the following warning: > > drivers/watchdog/cros_ec_wdt.c:29:40: warning: structure containing a > flexible array member is not at the end of another structure > [-Wflex-array-member-not-at-end] > > Reviewed-by: Tzung-Bi Shih <[email protected]> > Signed-off-by: Gustavo A. R. Silva <[email protected]> > --- > Changes v2: > - Fix truncated line in changelog text. (Tzung-Bi) > - Update variable name: s/buf/msg (Tzung-Bi) > - Cast to structs instead of union. (Tzung-Bi) > - Add RB tag. > > v1: > - Link: https://lore.kernel.org/linux-hardening/Z-SBITmMfwjocYwL@kspp/ > > drivers/watchdog/cros_ec_wdt.c | 30 +++++++++++++----------------- > 1 file changed, 13 insertions(+), 17 deletions(-) > > diff --git a/drivers/watchdog/cros_ec_wdt.c b/drivers/watchdog/cros_ec_wdt.c > index 716c23f4388c..9ffe7f505645 100644 > --- a/drivers/watchdog/cros_ec_wdt.c > +++ b/drivers/watchdog/cros_ec_wdt.c > @@ -25,26 +25,22 @@ static int cros_ec_wdt_send_cmd(struct cros_ec_device > *cros_ec, > union cros_ec_wdt_data *arg) > { > int ret; > - struct { > - struct cros_ec_command msg; > - union cros_ec_wdt_data data; > - } __packed buf = { > - .msg = { > - .version = 0, > - .command = EC_CMD_HANG_DETECT, > - .insize = (arg->req.command == > EC_HANG_DETECT_CMD_GET_STATUS) ? > - sizeof(struct ec_response_hang_detect) : > - 0, > - .outsize = sizeof(struct ec_params_hang_detect), > - }, > - .data.req = arg->req > - }; > - > - ret = cros_ec_cmd_xfer_status(cros_ec, &buf.msg); > + DEFINE_RAW_FLEX(struct cros_ec_command, msg, data, > + sizeof(union cros_ec_wdt_data)); > + > + msg->version = 0;
Technically redundant, but it was redundant before, so keeping style is okay. > + msg->command = EC_CMD_HANG_DETECT; > + msg->insize = (arg->req.command == EC_HANG_DETECT_CMD_GET_STATUS) ? > + sizeof(struct ec_response_hang_detect) : > + 0; > + msg->outsize = sizeof(struct ec_params_hang_detect); > + *(struct ec_params_hang_detect *)msg->data = arg->req; > + > + ret = cros_ec_cmd_xfer_status(cros_ec, msg); > if (ret < 0) > return ret; > > - arg->resp = buf.data.resp; > + arg->resp = *(struct ec_response_hang_detect *)msg->data; msg->data used twice and a "sizeof()" earlier... might be nicer to have an explicit pointer? -Kees > > return 0; > } > -- > 2.43.0 > -- Kees Cook
