@@ -1761,7 +1761,9 @@ static void ath12k_core_hw_group_destroy(struct ath12k_hw_group *ag)
if (!ab)
continue;
+ mutex_lock(&ab->core_lock);
ath12k_core_soc_destroy(ab);
+ mutex_unlock(&ab->core_lock);
}
mutex_unlock(&ag->mutex);
}
@@ -1,7 +1,7 @@
// SPDX-License-Identifier: BSD-3-Clause-Clear
/*
* Copyright (c) 2018-2021 The Linux Foundation. All rights reserved.
- * Copyright (c) 2021-2024 Qualcomm Innovation Center, Inc. All rights reserved.
+ * Copyright (c) 2021-2025 Qualcomm Innovation Center, Inc. All rights reserved.
*/
#include <linux/rtnetlink.h>
#include "core.h"
@@ -780,5 +780,7 @@ void ath12k_reg_free(struct ath12k_base *ab)
for (i = 0; i < ab->hw_params->max_radios; i++) {
kfree(ab->default_regd[i]);
kfree(ab->new_regd[i]);
+ ab->default_regd[i] = NULL;
+ ab->new_regd[i] = NULL;
}
}
During rmmod of ath12k module with SLUB debug enabled, following print is seen - ============================================================================= BUG kmalloc-1k (Not tainted): Object already free ----------------------------------------------------------------------------- Allocated in ath12k_reg_build_regd+0x94/0xa20 [ath12k] age=10470 cpu=0 pid=0 __kmalloc_noprof+0xf4/0x368 ath12k_reg_build_regd+0x94/0xa20 [ath12k] ath12k_wmi_op_rx+0x199c/0x2c14 [ath12k] ath12k_htc_rx_completion_handler+0x398/0x554 [ath12k] ath12k_ce_per_engine_service+0x248/0x368 [ath12k] ath12k_pci_ce_workqueue+0x28/0x50 [ath12k] process_one_work+0x14c/0x28c bh_worker+0x22c/0x27c workqueue_softirq_action+0x80/0x90 tasklet_action+0x14/0x3c handle_softirqs+0x108/0x240 __do_softirq+0x14/0x20 Freed in ath12k_reg_free+0x40/0x74 [ath12k] age=136 cpu=2 pid=166 kfree+0x148/0x248 ath12k_reg_free+0x40/0x74 [ath12k] ath12k_core_hw_group_destroy+0x68/0xac [ath12k] ath12k_core_deinit+0xd8/0x124 [ath12k] ath12k_pci_remove+0x6c/0x130 [ath12k] pci_device_remove+0x44/0xe8 device_remove+0x4c/0x80 device_release_driver_internal+0x1d0/0x22c driver_detach+0x50/0x98 bus_remove_driver+0x70/0xf4 driver_unregister+0x30/0x60 pci_unregister_driver+0x24/0x9c ath12k_pci_exit+0x18/0x24 [ath12k] __arm64_sys_delete_module+0x1a0/0x2a8 invoke_syscall+0x48/0x110 el0_svc_common.constprop.0+0x40/0xe0 Slab 0xfffffdffc0033600 objects=10 used=6 fp=0xffff000000cdcc00 flags=0x3fffe0000000240(workingset|head|node=0|zone=0|lastcpupid=0x1ffff) Object 0xffff000000cdcc00 @offset=19456 fp=0xffff000000cde400 [...] This issue arises because in ath12k_core_hw_group_destroy(), each device calls ath12k_core_soc_destroy() for itself and all its partners within the same group. Since ath12k_core_hw_group_destroy() is invoked for each device, this results in a double free condition, eventually causing the SLUB bug. To resolve this, set the freed pointers to NULL. And since there could be a race condition to read these pointers, guard ath12k_core_soc_destroy() with the mutex lock. Tested-on: QCN9274 hw2.0 PCI WLAN.WBE.1.3.1-00173-QCAHKSWPL_SILICONZ-1 Fixes: 6f245ea0ec6c ("wifi: ath12k: introduce device group abstraction") Signed-off-by: Aditya Kumar Singh <quic_adisi@quicinc.com> --- drivers/net/wireless/ath/ath12k/core.c | 2 ++ drivers/net/wireless/ath/ath12k/reg.c | 4 +++- 2 files changed, 5 insertions(+), 1 deletion(-)