From: Johannes Berg <johannes.berg@xxxxxxxxx> Upstream commit 7245012f0f496162dd95d888ed2ceb5a35170f1a. If more than 255 colocated APs exist for the set of all APs found during 2.4/5 GHz scanning, then the 6 GHz scan construction will loop forever since the loop variable has type u8, which can never reach the number found when that's bigger than 255, and is stored in a u32 variable. Also move it into the loops to have a smaller scope. Using a u32 there is fine, we limit the number of APs in the scan list and each has a limit on the number of RNR entries due to the frame size. With a limit of 1000 scan results, a frame size upper bound of 4096 (really it's more like ~2300) and a TBTT entry size of at least 11, we get an upper bound for the number of ~372k, well in the bounds of a u32. Cc: stable@xxxxxxxxxxxxxxx Fixes: eae94cf82d74 ("iwlwifi: mvm: add support for 6GHz") Closes: https://bugzilla.kernel.org/show_bug.cgi?id=219375 Link: https://patch.msgid.link/20241023091744.f4baed5c08a1.I8b417148bbc8c5d11c101e1b8f5bf372e17bf2a7@changeid Signed-off-by: Johannes Berg <johannes.berg@xxxxxxxxx> --- drivers/net/wireless/intel/iwlwifi/mvm/scan.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/net/wireless/intel/iwlwifi/mvm/scan.c b/drivers/net/wireless/intel/iwlwifi/mvm/scan.c index aa6ef6491205..16818dcdae22 100644 --- a/drivers/net/wireless/intel/iwlwifi/mvm/scan.c +++ b/drivers/net/wireless/intel/iwlwifi/mvm/scan.c @@ -1753,7 +1753,8 @@ iwl_mvm_umac_scan_cfg_channels_v6_6g(struct iwl_mvm_scan_params *params, &cp->channel_config[i]; u32 s_ssid_bitmap = 0, bssid_bitmap = 0, flags = 0; - u8 j, k, s_max = 0, b_max = 0, n_used_bssid_entries; + u8 k, s_max = 0, b_max = 0, n_used_bssid_entries; + u32 j; bool force_passive, found = false, allow_passive = true, unsolicited_probe_on_chan = false, psc_no_listen = false; -- 2.47.0