CVE-2022-49519

In the Linux kernel, the following vulnerability has been resolved:<br /> <br /> ath10k: skip ath10k_halt during suspend for driver state RESTARTING<br /> <br /> Double free crash is observed when FW recovery(caused by wmi<br /> timeout/crash) is followed by immediate suspend event. The FW recovery<br /> is triggered by ath10k_core_restart() which calls driver clean up via<br /> ath10k_halt(). When the suspend event occurs between the FW recovery,<br /> the restart worker thread is put into frozen state until suspend completes.<br /> The suspend event triggers ath10k_stop() which again triggers ath10k_halt()<br /> The double invocation of ath10k_halt() causes ath10k_htt_rx_free() to be<br /> called twice(Note: ath10k_htt_rx_alloc was not called by restart worker<br /> thread because of its frozen state), causing the crash.<br /> <br /> To fix this, during the suspend flow, skip call to ath10k_halt() in<br /> ath10k_stop() when the current driver state is ATH10K_STATE_RESTARTING.<br /> Also, for driver state ATH10K_STATE_RESTARTING, call<br /> ath10k_wait_for_suspend() in ath10k_stop(). This is because call to<br /> ath10k_wait_for_suspend() is skipped later in<br /> [ath10k_halt() &gt; ath10k_core_stop()] for the driver state<br /> ATH10K_STATE_RESTARTING.<br /> <br /> The frozen restart worker thread will be cancelled during resume when the<br /> device comes out of suspend.<br /> <br /> Below is the crash stack for reference:<br /> <br /> [ 428.469167] ------------[ cut here ]------------<br /> [ 428.469180] kernel BUG at mm/slub.c:4150!<br /> [ 428.469193] invalid opcode: 0000 [#1] PREEMPT SMP NOPTI<br /> [ 428.469219] Workqueue: events_unbound async_run_entry_fn<br /> [ 428.469230] RIP: 0010:kfree+0x319/0x31b<br /> [ 428.469241] RSP: 0018:ffffa1fac015fc30 EFLAGS: 00010246<br /> [ 428.469247] RAX: ffffedb10419d108 RBX: ffff8c05262b0000<br /> [ 428.469252] RDX: ffff8c04a8c07000 RSI: 0000000000000000<br /> [ 428.469256] RBP: ffffa1fac015fc78 R08: 0000000000000000<br /> [ 428.469276] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033<br /> [ 428.469285] Call Trace:<br /> [ 428.469295] ? dma_free_attrs+0x5f/0x7d<br /> [ 428.469320] ath10k_core_stop+0x5b/0x6f<br /> [ 428.469336] ath10k_halt+0x126/0x177<br /> [ 428.469352] ath10k_stop+0x41/0x7e<br /> [ 428.469387] drv_stop+0x88/0x10e<br /> [ 428.469410] __ieee80211_suspend+0x297/0x411<br /> [ 428.469441] rdev_suspend+0x6e/0xd0<br /> [ 428.469462] wiphy_suspend+0xb1/0x105<br /> [ 428.469483] ? name_show+0x2d/0x2d<br /> [ 428.469490] dpm_run_callback+0x8c/0x126<br /> [ 428.469511] ? name_show+0x2d/0x2d<br /> [ 428.469517] __device_suspend+0x2e7/0x41b<br /> [ 428.469523] async_suspend+0x1f/0x93<br /> [ 428.469529] async_run_entry_fn+0x3d/0xd1<br /> [ 428.469535] process_one_work+0x1b1/0x329<br /> [ 428.469541] worker_thread+0x213/0x372<br /> [ 428.469547] kthread+0x150/0x15f<br /> [ 428.469552] ? pr_cont_work+0x58/0x58<br /> [ 428.469558] ? kthread_blkcg+0x31/0x31<br /> <br /> Tested-on: QCA6174 hw3.2 PCI WLAN.RM.4.4.1-00288-QCARMSWPZ-1