From 4c6eb712a91fa079be6f9f1419c96e0ad2227081 Mon Sep 17 00:00:00 2001 From: Jeff Johnson Date: Tue, 28 Jul 2026 18:05:28 -0700 Subject: [PATCH] wifi: ath12k: fix stride mismatch in mac_phy_caps_parse() Currently, in ath12k_wmi_mac_phy_caps_parse(), kzalloc() sizes the mac_phy_caps buffer as tot_phy_id * len, where len is clamped to min(firmware_len, sizeof(struct ath12k_wmi_mac_phy_caps_params)). The subsequent memcpy() destination advances by sizeof(full struct) per slot via C pointer arithmetic, not by the clamped len. When firmware sends short TLVs, the second and later slots are written past the end of the allocation. The reader in ath12k_pull_mac_phy_cap_svc_ready_ext() also indexes the buffer with full-struct pointer arithmetic, so the allocation must match that stride. Fix by using kzalloc_objs(), which derives the element size from the pointer type, making allocation size and pointer stride provably consistent regardless of what len the firmware provides. Tested-on: WCN7850 hw2.0 PCI WLAN.HMT.1.1.c7-00108-QCAHMTSWPL_V1.0_V2.0_SILICONZ_UPSTREAM-3 Fixes: d889913205cf ("wifi: ath12k: driver for Qualcomm Wi-Fi 7 devices") Assisted-by: Claude:claude-sonnet-4-6 Reviewed-by: Baochen Qiang Reviewed-by: Rameshkumar Sundaram Link: https://patch.msgid.link/20260728-mac_phy_caps_parse-stride-mismatch-v1-1-27a9c1a3fbd0@oss.qualcomm.com Signed-off-by: Jeff Johnson --- drivers/net/wireless/ath/ath12k/wmi.c | 8 +++++--- 1 file changed, 5 insertions(+), 3 deletions(-) diff --git a/drivers/net/wireless/ath/ath12k/wmi.c b/drivers/net/wireless/ath/ath12k/wmi.c index e9e7566e0f69..d5160af60e00 100644 --- a/drivers/net/wireless/ath/ath12k/wmi.c +++ b/drivers/net/wireless/ath/ath12k/wmi.c @@ -4774,14 +4774,16 @@ static int ath12k_wmi_mac_phy_caps_parse(struct ath12k_base *soc, if (svc_rdy_ext->n_mac_phy_caps >= svc_rdy_ext->tot_phy_id) return -ENOBUFS; - len = min_t(u16, len, sizeof(struct ath12k_wmi_mac_phy_caps_params)); if (!svc_rdy_ext->n_mac_phy_caps) { - svc_rdy_ext->mac_phy_caps = kzalloc((svc_rdy_ext->tot_phy_id) * len, - GFP_ATOMIC); + svc_rdy_ext->mac_phy_caps = + kzalloc_objs(*svc_rdy_ext->mac_phy_caps, + svc_rdy_ext->tot_phy_id, + GFP_ATOMIC); if (!svc_rdy_ext->mac_phy_caps) return -ENOMEM; } + len = min_t(u16, len, sizeof(struct ath12k_wmi_mac_phy_caps_params)); memcpy(svc_rdy_ext->mac_phy_caps + svc_rdy_ext->n_mac_phy_caps, ptr, len); svc_rdy_ext->n_mac_phy_caps++; return 0;