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). Also, -Wflex-array-member-not-at-end is coming in GCC-14, and we are getting ready to enable it globally. So, use the `DEFINE_FLEX()` helper for an on-stack definition 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/net/wireless/ath/wil6210/wmi.c:4018:49: warning: structure containing a flexible array member is not at the end of another structure [-Wflex-array-member-not-at-end] Link: https://github.com/KSPP/linux/issues/202 Signed-off-by: Gustavo A. R. Silva <gustavoars@xxxxxxxxxx> --- Changes in v2: - Use __struct_size() to get the compile-time size of the flex-struct instance. v1: - Link: https://lore.kernel.org/linux-hardening/ZgRsn72WkHzfCUsa@neat/ drivers/net/wireless/ath/wil6210/wmi.c | 19 +++++++------------ drivers/net/wireless/ath/wil6210/wmi.h | 2 +- 2 files changed, 8 insertions(+), 13 deletions(-) diff --git a/drivers/net/wireless/ath/wil6210/wmi.c b/drivers/net/wireless/ath/wil6210/wmi.c index 6fdb77d4c59e..8ff69dc72fb9 100644 --- a/drivers/net/wireless/ath/wil6210/wmi.c +++ b/drivers/net/wireless/ath/wil6210/wmi.c @@ -4014,28 +4014,23 @@ int wmi_set_cqm_rssi_config(struct wil6210_priv *wil, struct net_device *ndev = wil->main_ndev; struct wil6210_vif *vif = ndev_to_vif(ndev); int rc; - struct { - struct wmi_set_link_monitor_cmd cmd; - s8 rssi_thold; - } __packed cmd = { - .cmd = { - .rssi_hyst = rssi_hyst, - .rssi_thresholds_list_size = 1, - }, - .rssi_thold = rssi_thold, - }; struct { struct wmi_cmd_hdr hdr; struct wmi_set_link_monitor_event evt; } __packed reply = { .evt = {.status = WMI_FW_STATUS_FAILURE}, }; + DEFINE_FLEX(struct wmi_set_link_monitor_cmd, cmd, + rssi_thresholds_list, rssi_thresholds_list_size, 1); + + cmd->rssi_hyst = rssi_hyst; + cmd->rssi_thresholds_list[0] = rssi_thold; if (rssi_thold > S8_MAX || rssi_thold < S8_MIN || rssi_hyst > U8_MAX) return -EINVAL; - rc = wmi_call(wil, WMI_SET_LINK_MONITOR_CMDID, vif->mid, &cmd, - sizeof(cmd), WMI_SET_LINK_MONITOR_EVENTID, + rc = wmi_call(wil, WMI_SET_LINK_MONITOR_CMDID, vif->mid, cmd, + __struct_size(cmd), WMI_SET_LINK_MONITOR_EVENTID, &reply, sizeof(reply), WIL_WMI_CALL_GENERAL_TO_MS); if (rc) { wil_err(wil, "WMI_SET_LINK_MONITOR_CMDID failed, rc %d\n", rc); diff --git a/drivers/net/wireless/ath/wil6210/wmi.h b/drivers/net/wireless/ath/wil6210/wmi.h index b47606d9068c..38f64524019e 100644 --- a/drivers/net/wireless/ath/wil6210/wmi.h +++ b/drivers/net/wireless/ath/wil6210/wmi.h @@ -3320,7 +3320,7 @@ struct wmi_set_link_monitor_cmd { u8 rssi_hyst; u8 reserved[12]; u8 rssi_thresholds_list_size; - s8 rssi_thresholds_list[]; + s8 rssi_thresholds_list[] __counted_by(rssi_thresholds_list_size); } __packed; /* wmi_link_monitor_event_type */ -- 2.34.1
