From: Kalle Valo <quic_kvalo@xxxxxxxxxxx> Linaro reported stringop-overread warnings in ath11k (this is one of many): drivers/net/wireless/ath/ath11k/mac.c:2238:29: error: 'ath11k_peer_assoc_h_he_limit' reading 16 bytes from a region of size 0 [-Werror=stringop-overread] My further investigation showed that these warnings happen on GCC 11.3 but not with GCC 12.2, and with only the kernel config Linaro provided: https://builds.tuxbuild.com/2F4W7nZHNx3T88RB0gaCZ9hBX6c/config I saw the same warnings both with arm64 and x86_64 builds but couldn't figure out what exactly triggers the warnings, or why I didn't see them earlier. Nobody else has reported this either. This is also why I can't provide a Fixes tag as I don't know what's causing this. The function hasn't been touched for a year. I decided to fix this by converting the pointer to a new array in stack, and then copying the data to the new array. It's only 16 bytes anyway and this is executed during association, so not in a hotpath. Tested-on: WCN6855 hw2.0 PCI WLAN.HSP.1.1-03125-QCAHSPSWPL_V1_V2_SILICONZ_LITE-3.6510.9 Reported-by: Linux Kernel Functional Testing <lkft@xxxxxxxxxx> Link: https://lore.kernel.org/all/CA+G9fYsZ_qypa=jHY_dJ=tqX4515+qrV9n2SWXVDHve826nF7Q@xxxxxxxxxxxxxx/ Signed-off-by: Kalle Valo <quic_kvalo@xxxxxxxxxxx> --- drivers/net/wireless/ath/ath11k/mac.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/drivers/net/wireless/ath/ath11k/mac.c b/drivers/net/wireless/ath/ath11k/mac.c index 84d956ad4093..2d1e3fd9b526 100644 --- a/drivers/net/wireless/ath/ath11k/mac.c +++ b/drivers/net/wireless/ath/ath11k/mac.c @@ -2081,7 +2081,7 @@ static void ath11k_peer_assoc_h_he(struct ath11k *ar, struct cfg80211_chan_def def; const struct ieee80211_sta_he_cap *he_cap = &sta->deflink.he_cap; enum nl80211_band band; - u16 *he_mcs_mask; + u16 he_mcs_mask[NL80211_HE_NSS_MAX]; u8 max_nss, he_mcs; u16 he_tx_mcs = 0, v = 0; int i, he_nss, nss_idx; @@ -2098,7 +2098,8 @@ static void ath11k_peer_assoc_h_he(struct ath11k *ar, return; band = def.chan->band; - he_mcs_mask = arvif->bitrate_mask.control[band].he_mcs; + memcpy(he_mcs_mask, arvif->bitrate_mask.control[band].he_mcs, + sizeof(he_mcs_mask)); if (ath11k_peer_assoc_h_he_masked(he_mcs_mask)) return; base-commit: 10d5ea5a436da8d60cdb5845f454d595accdbce0 -- 2.30.2
