CVE-2022-50716
wifi: ar5523: Fix use-after-free on ar5523_cmd() timed out
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Description
In the Linux kernel, the following vulnerability has been resolved: wifi: ar5523: Fix use-after-free on ar5523_cmd() timed out syzkaller reported use-after-free with the stack trace like below [1]: [ 38.960489][ C3] ================================================================== [ 38.963216][ C3] BUG: KASAN: use-after-free in ar5523_cmd_tx_cb+0x220/0x240 [ 38.964950][ C3] Read of size 8 at addr ffff888048e03450 by task swapper/3/0 [ 38.966363][ C3] [ 38.967053][ C3] CPU: 3 PID: 0 Comm: swapper/3 Not tainted 6.0.0-09039-ga6afa4199d3d-dirty #18 [ 38.968464][ C3] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.0-1.fc36 04/01/2014 [ 38.969959][ C3] Call Trace: [ 38.970841][ C3] <IRQ> [ 38.971663][ C3] dump_stack_lvl+0xfc/0x174 [ 38.972620][ C3] print_report.cold+0x2c3/0x752 [ 38.973626][ C3] ? ar5523_cmd_tx_cb+0x220/0x240 [ 38.974644][ C3] kasan_report+0xb1/0x1d0 [ 38.975720][ C3] ? ar5523_cmd_tx_cb+0x220/0x240 [ 38.976831][ C3] ar5523_cmd_tx_cb+0x220/0x240 [ 38.978412][ C3] __usb_hcd_giveback_urb+0x353/0x5b0 [ 38.979755][ C3] usb_hcd_giveback_urb+0x385/0x430 [ 38.981266][ C3] dummy_timer+0x140c/0x34e0 [ 38.982925][ C3] ? notifier_call_chain+0xb5/0x1e0 [ 38.984761][ C3] ? rcu_read_lock_sched_held+0xb/0x60 [ 38.986242][ C3] ? lock_release+0x51c/0x790 [ 38.987323][ C3] ? _raw_read_unlock_irqrestore+0x37/0x70 [ 38.988483][ C3] ? __wake_up_common_lock+0xde/0x130 [ 38.989621][ C3] ? reacquire_held_locks+0x4a0/0x4a0 [ 38.990777][ C3] ? lock_acquire+0x472/0x550 [ 38.991919][ C3] ? rcu_read_lock_sched_held+0xb/0x60 [ 38.993138][ C3] ? lock_acquire+0x472/0x550 [ 38.994890][ C3] ? dummy_urb_enqueue+0x860/0x860 [ 38.996266][ C3] ? do_raw_spin_unlock+0x16f/0x230 [ 38.997670][ C3] ? dummy_urb_enqueue+0x860/0x860 [ 38.999116][ C3] call_timer_fn+0x1a0/0x6a0 [ 39.000668][ C3] ? add_timer_on+0x4a0/0x4a0 [ 39.002137][ C3] ? reacquire_held_locks+0x4a0/0x4a0 [ 39.003809][ C3] ? __next_timer_interrupt+0x226/0x2a0 [ 39.005509][ C3] __run_timers.part.0+0x69a/0xac0 [ 39.007025][ C3] ? dummy_urb_enqueue+0x860/0x860 [ 39.008716][ C3] ? call_timer_fn+0x6a0/0x6a0 [ 39.010254][ C3] ? cpuacct_percpu_seq_show+0x10/0x10 [ 39.011795][ C3] ? kvm_sched_clock_read+0x14/0x40 [ 39.013277][ C3] ? sched_clock_cpu+0x69/0x2b0 [ 39.014724][ C3] run_timer_softirq+0xb6/0x1d0 [ 39.016196][ C3] __do_softirq+0x1d2/0x9be [ 39.017616][ C3] __irq_exit_rcu+0xeb/0x190 [ 39.019004][ C3] irq_exit_rcu+0x5/0x20 [ 39.020361][ C3] sysvec_apic_timer_interrupt+0x8f/0xb0 [ 39.021965][ C3] </IRQ> [ 39.023237][ C3] <TASK> In ar5523_probe(), ar5523_host_available() calls ar5523_cmd() as below (there are other functions which finally call ar5523_cmd()): ar5523_probe() -> ar5523_host_available() -> ar5523_cmd_read() -> ar5523_cmd() If ar5523_cmd() timed out, then ar5523_host_available() failed and ar5523_probe() freed the device structure. So, ar5523_cmd_tx_cb() might touch the freed structure. This patch fixes this issue by canceling in-flight tx cmd if submitted urb timed out.
Affected
Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.
Remediation
No guide yetNo remediation guidance has been written for this CVE yet, and no fixed version or vendor advisory is recorded against it.
References (9)
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