This is a note to let you know that I've just added the patch titled wifi: ath11k: initialize rx_mcs_80 and rx_mcs_160 before use to the 6.6-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: wifi-ath11k-initialize-rx_mcs_80-and-rx_mcs_160-befo.patch and it can be found in the queue-6.6 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit f2d24011f88eadaf6988a67054791b83b1e00a3f Author: Baochen Qiang <quic_bqiang@xxxxxxxxxxx> Date: Fri Feb 2 10:35:47 2024 +0800 wifi: ath11k: initialize rx_mcs_80 and rx_mcs_160 before use [ Upstream commit b802e7b7e771dee3377d071418281f8b64d2d832 ] Currently in ath11k_peer_assoc_h_he() rx_mcs_80 and rx_mcs_160 are used to calculate max_nss, see if (support_160) max_nss = min(rx_mcs_80, rx_mcs_160); else max_nss = rx_mcs_80; Kernel test robot complains on uninitialized symbols: drivers/net/wireless/ath/ath11k/mac.c:2321 ath11k_peer_assoc_h_he() error: uninitialized symbol 'rx_mcs_80'. drivers/net/wireless/ath/ath11k/mac.c:2321 ath11k_peer_assoc_h_he() error: uninitialized symbol 'rx_mcs_160'. drivers/net/wireless/ath/ath11k/mac.c:2323 ath11k_peer_assoc_h_he() error: uninitialized symbol 'rx_mcs_80'. This is because there are some code paths that never set them, so the assignment of max_nss can come from uninitialized variables. This could result in some unknown issues since a wrong peer_nss might be passed to firmware. Change to initialize them to an invalid value at the beginning. This makes sense because even max_nss gets an invalid value, due to either or both of them being invalid, we can get an valid peer_nss with following guard: arg->peer_nss = min(sta->deflink.rx_nss, max_nss) Tested-on: WCN6855 hw2.1 PCI WLAN.HSP.1.1-03125-QCAHSPSWPL_V1_V2_SILICONZ_LITE-3.6510.23 Fixes: 3db26ecf7114 ("ath11k: calculate the correct NSS of peer for HE capabilities") Reported-by: kernel test robot <lkp@xxxxxxxxx> Closes: https://lore.kernel.org/oe-kbuild-all/202401311243.NyXwWZxP-lkp@xxxxxxxxx/ Signed-off-by: Baochen Qiang <quic_bqiang@xxxxxxxxxxx> Acked-by: Jeff Johnson <quic_jjohnson@xxxxxxxxxxx> Signed-off-by: Kalle Valo <quic_kvalo@xxxxxxxxxxx> Link: https://msgid.link/20240202023547.11141-1-quic_bqiang@xxxxxxxxxxx Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/drivers/net/wireless/ath/ath11k/mac.c b/drivers/net/wireless/ath/ath11k/mac.c index 8880462549b7f..b75cb49c27466 100644 --- a/drivers/net/wireless/ath/ath11k/mac.c +++ b/drivers/net/wireless/ath/ath11k/mac.c @@ -2296,6 +2296,8 @@ static void ath11k_peer_assoc_h_he(struct ath11k *ar, mcs_160_map = le16_to_cpu(he_cap->he_mcs_nss_supp.rx_mcs_160); mcs_80_map = le16_to_cpu(he_cap->he_mcs_nss_supp.rx_mcs_80); + /* Initialize rx_mcs_160 to 9 which is an invalid value */ + rx_mcs_160 = 9; if (support_160) { for (i = 7; i >= 0; i--) { u8 mcs_160 = (mcs_160_map >> (2 * i)) & 3; @@ -2307,6 +2309,8 @@ static void ath11k_peer_assoc_h_he(struct ath11k *ar, } } + /* Initialize rx_mcs_80 to 9 which is an invalid value */ + rx_mcs_80 = 9; for (i = 7; i >= 0; i--) { u8 mcs_80 = (mcs_80_map >> (2 * i)) & 3;