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 <baochen.qiang@oss.qualcomm.com>
Reviewed-by: Rameshkumar Sundaram <rameshkumar.sundaram@oss.qualcomm.com>
Link: https://patch.msgid.link/20260728-mac_phy_caps_parse-stride-mismatch-v1-1-27a9c1a3fbd0@oss.qualcomm.com
Signed-off-by: Jeff Johnson <jeff.johnson@oss.qualcomm.com>

0 files changed, 0 insertions, 0 deletions