6.11-stable review patch. If anyone has any objections, please let me know.
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From: Rameshkumar Sundaram quic_ramess@quicinc.com
[ Upstream commit bdb281103373fd80eb5c91cede1e115ba270b4e9 ]
During ath12k module removal, in ath12k_core_deinit(), ath12k_mac_destroy() un-registers ah->hw from mac80211 and frees the ah->hw as well as all the ar's in it. After this ath12k_core_soc_destroy()-> ath12k_dp_free()-> ath12k_dp_cc_cleanup() tries to access one of the freed ar's from pending skb.
This is because during mac destroy, driver failed to flush few data packets, which were accessed later in ath12k_dp_cc_cleanup() and freed, but using ar from the packet led to this use-after-free.
BUG: KASAN: use-after-free in ath12k_dp_cc_cleanup.part.0+0x5e2/0xd40 [ath12k] Write of size 4 at addr ffff888150bd3514 by task modprobe/8926 CPU: 0 UID: 0 PID: 8926 Comm: modprobe Not tainted 6.11.0-rc2-wt-ath+ #1746 Hardware name: Intel(R) Client Systems NUC8i7HVK/NUC8i7HVB, BIOS HNKBLi70.86A.0067.2021.0528.1339 05/28/2021
Call Trace: <TASK> dump_stack_lvl+0x7d/0xe0 print_address_description.constprop.0+0x33/0x3a0 print_report+0xb5/0x260 ? kasan_addr_to_slab+0x24/0x80 kasan_report+0xd8/0x110 ? ath12k_dp_cc_cleanup.part.0+0x5e2/0xd40 [ath12k] ? ath12k_dp_cc_cleanup.part.0+0x5e2/0xd40 [ath12k] kasan_check_range+0xf3/0x1a0 __kasan_check_write+0x14/0x20 ath12k_dp_cc_cleanup.part.0+0x5e2/0xd40 [ath12k] ath12k_dp_free+0x178/0x420 [ath12k] ath12k_core_stop+0x176/0x200 [ath12k] ath12k_core_deinit+0x13f/0x210 [ath12k] ath12k_pci_remove+0xad/0x1c0 [ath12k] pci_device_remove+0x9b/0x1b0 device_remove+0xbf/0x150 device_release_driver_internal+0x3c3/0x580 ? __kasan_check_read+0x11/0x20 driver_detach+0xc4/0x190 bus_remove_driver+0x130/0x2a0 driver_unregister+0x68/0x90 pci_unregister_driver+0x24/0x240 ? find_module_all+0x13e/0x1e0 ath12k_pci_exit+0x10/0x20 [ath12k] __do_sys_delete_module+0x32c/0x580 ? module_flags+0x2f0/0x2f0 ? kmem_cache_free+0xf0/0x410 ? __fput+0x56f/0xab0 ? __fput+0x56f/0xab0 ? debug_smp_processor_id+0x17/0x20 __x64_sys_delete_module+0x4f/0x70 x64_sys_call+0x522/0x9f0 do_syscall_64+0x64/0x130 entry_SYSCALL_64_after_hwframe+0x4b/0x53 RIP: 0033:0x7f8182c6ac8b
Commit 24de1b7b231c ("wifi: ath12k: fix flush failure in recovery scenarios") added the change to decrement the pending packets count in case of recovery which make sense as ah->hw as well all ar's in it are intact during recovery, but during core deinit there is no use in decrementing packets count or waking up the empty waitq as the module is going to be removed also ar's from pending skb's can't be used and the packets should just be released back.
To fix this, avoid accessing ar from skb->cb when driver is being unregistered.
Tested-on: QCN9274 hw2.0 PCI WLAN.WBE.1.1.1-00214-QCAHKSWPL_SILICONZ-1 Tested-on: WCN7850 hw2.0 PCI WLAN.HMT.1.0.c5-00481-QCAHMTSWPL_V1.0_V2.0_SILICONZ-3
Fixes: 24de1b7b231c ("wifi: ath12k: fix flush failure in recovery scenarios") Signed-off-by: Rameshkumar Sundaram quic_ramess@quicinc.com Acked-by: Jeff Johnson quic_jjohnson@quicinc.com Link: https://patch.msgid.link/20241001092652.3134334-1-quic_ramess@quicinc.com Signed-off-by: Jeff Johnson quic_jjohnson@quicinc.com Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/net/wireless/ath/ath12k/dp.c | 14 ++++++++++---- 1 file changed, 10 insertions(+), 4 deletions(-)
diff --git a/drivers/net/wireless/ath/ath12k/dp.c b/drivers/net/wireless/ath/ath12k/dp.c index 61aa78d8bd8c8..abddeafabfa1b 100644 --- a/drivers/net/wireless/ath/ath12k/dp.c +++ b/drivers/net/wireless/ath/ath12k/dp.c @@ -1202,10 +1202,16 @@ static void ath12k_dp_cc_cleanup(struct ath12k_base *ab) if (!skb) continue;
- skb_cb = ATH12K_SKB_CB(skb); - ar = skb_cb->ar; - if (atomic_dec_and_test(&ar->dp.num_tx_pending)) - wake_up(&ar->dp.tx_empty_waitq); + /* if we are unregistering, hw would've been destroyed and + * ar is no longer valid. + */ + if (!(test_bit(ATH12K_FLAG_UNREGISTERING, &ab->dev_flags))) { + skb_cb = ATH12K_SKB_CB(skb); + ar = skb_cb->ar; + + if (atomic_dec_and_test(&ar->dp.num_tx_pending)) + wake_up(&ar->dp.tx_empty_waitq); + }
dma_unmap_single(ab->dev, ATH12K_SKB_CB(skb)->paddr, skb->len, DMA_TO_DEVICE);