Improper Locking

In the Linux kernel, the following vulnerability has been resolved: Revert "ALSA: firewire-lib: operate for period elapse event in process context" Commit 7ba5ca32fe6e ("ALSA: firewire-lib: operate for period elapse event in process context") removed the process context workqueue from amdtp_domain_stream_pcm_pointer() and update_pcm_pointers() to remove its overhead. With RME Fireface 800, this lead to a regression since Kernels 5.14.0, causing an AB/BA deadlock competition for the substream lock with eventual system freeze under ALSA operation: thread 0: * (lock A) acquire substream lock by snd_pcm_stream_lock_irq() in snd_pcm_status64() * (lock B) wait for tasklet to finish by calling tasklet_unlock_spin_wait() in tasklet_disable_in_atomic() in ohci_flush_iso_completions() of ohci.c thread 1: * (lock B) enter tasklet * (lock A) attempt to acquire substream lock, waiting for it to be released: snd_pcm_stream_lock_irqsave() in snd_pcm_period_elapsed() in update_pcm_pointers() in process_ctx_payloads() in process_rx_packets() of amdtp-stream.c ? tasklet_unlock_spin_wait </NMI> <TASK> ohci_flush_iso_completions firewire_ohci amdtp_domain_stream_pcm_pointer snd_firewire_lib snd_pcm_update_hw_ptr0 snd_pcm snd_pcm_status64 snd_pcm ? native_queued_spin_lock_slowpath </NMI> <IRQ> _raw_spin_lock_irqsave snd_pcm_period_elapsed snd_pcm process_rx_packets snd_firewire_lib irq_target_callback snd_firewire_lib handle_it_packet firewire_ohci context_tasklet firewire_ohci Restore the process context work queue to prevent deadlock AB/BA deadlock competition for ALSA substream lock of snd_pcm_stream_lock_irq() in snd_pcm_status64() and snd_pcm_stream_lock_irqsave() in snd_pcm_period_elapsed(). revert commit 7ba5ca32fe6e ("ALSA: firewire-lib: operate for period elapse event in process context") Replace inline description to prevent future deadlock.Show less

In the Linux kernel, the following vulnerability has been resolved: net/mlx5: Fix missing lock on sync reset reload On sync reset reload work, when remote host updates devlink on reload actions performed on that host, it misses taking devlink lock before calling devlink_remote_reload_actions_performed() which results in triggering lock assert like the following: WARNING: CPU: 4 PID: 1164 at net/devlink/core.c:261 devl_assert_locked+0x3e/0x50 … CPU: 4 PID: 1164 Comm: kworker/u96:6 Tainted: G S W 6.10.0-rc2+ #116 Hardware name: Supermicro SYS-2028TP-DECTR/X10DRT-PT, BIOS 2.0 12/18/2015 Workqueue: mlx5_fw_reset_events mlx5_sync_reset_reload_work [mlx5_core] RIP: 0010:devl_assert_locked+0x3e/0x50 … Call Trace: <TASK> ? __warn+0xa4/0x210 ? devl_assert_locked+0x3e/0x50 ? report_bug+0x160/0x280 ? handle_bug+0x3f/0x80 ? exc_invalid_op+0x17/0x40 ? asm_exc_invalid_op+0x1a/0x20 ? devl_assert_locked+0x3e/0x50 devlink_notify+0x88/0x2b0 ? mlx5_attach_device+0x20c/0x230 [mlx5_core] ? __pfx_devlink_notify+0x10/0x10 ? process_one_work+0x4b6/0xbb0 process_one_work+0x4b6/0xbb0 […]Show less

In the Linux kernel, the following vulnerability has been resolved: gpio: pca953x: fix pca953x_irq_bus_sync_unlock race Ensure that `i2c_lock' is held when setting interrupt latch and mask in pca953x_irq_bus_sync_unlock() in order to avoid races. The other (non-probe) call site pca953x_gpio_set_multiple() ensures the lock is held before calling pca953x_write_regs(). The problem occurred when a request raced against irq_bus_sync_unlock() approximately once per thousand reboots on an i.MX8MP based system. * Normal case 0-0022: write register AI|3a {03,02,00,00,01} Input latch P0 0-0022: write register AI|49 {fc,fd,ff,ff,fe} Interrupt mask P0 0-0022: write register AI|08 {ff,00,00,00,00} Output P3 0-0022: write register AI|12 {fc,00,00,00,00} Config P3 * Race case 0-0022: write register AI|08 {ff,00,00,00,00} Output P3 0-0022: write register AI|08 {03,02,00,00,01} *** Wrong register *** 0-0022: write register AI|12 {fc,00,00,00,00} Config P3 0-0022: write register AI|49 {fc,fd,ff,ff,fe} Interrupt mask P0Show less

In the Linux kernel, the following vulnerability has been resolved: cachefiles: add missing lock protection when polling Add missing lock protection in poll routine when iterating xarray, otherwise: Even with RCU read lock held, only the slot of the radix tree is ensured to be pinned there, while the data structure (e.g. struct cachefiles_req) stored in the slot has no such guarantee. The poll routine will iterate the radix tree and dereference cachefiles_req accordingly. Thus RCU read lock is not adequate in this case and spinlock is needed here.Show less

In the Linux kernel, the following vulnerability has been resolved: Revert "sched/fair: Make sure to try to detach at least one movable task" This reverts commit b0defa7ae03ecf91b8bfd10ede430cff12fcbd06. b0defa7ae03ec changed the load balancing logic to ignore env.max_loop if all tasks examined to that point were pinned. The goal of the patch was to make it more likely to be able to detach a task buried in a long list of pinned tasks. However, this has the unfortunate side effect of creating an O(n) iteration in detach_tasks(), as we now must fully iterate every task on a cpu if all or most are pinned. Since this load balance code is done with rq lock held, and often in softirq context, it is very easy to trigger hard lockups. We observed such hard lockups with a user who affined O(10k) threads to a single cpu. When I discussed this with Vincent he initially suggested that we keep the limit on the number of tasks to detach, but increase the number of tasks we can search. However, after some back and forth on the mailing list, he recommended we instead revert the original patch, as it seems likely no one was actually getting hit by the original issue.Show less

In the Linux kernel, the following vulnerability has been resolved: bpf: Fail bpf_timer_cancel when callback is being cancelled Given a schedule: timer1 cb timer2 cb bpf_timer_cancel(timer2); bpf_timer_cancel(timer1); Both bpf_timer_cancel calls would wait for the other callback to finish executing, introducing a lockup. Add an atomic_t count named 'cancelling' in bpf_hrtimer. This keeps track of all in-flight cancellation requests for a given BPF timer. Whenever cancelling a BPF timer, we must check if we have outstanding cancellation requests, and if so, we must fail the operation with an error (-EDEADLK) since cancellation is synchronous and waits for the callback to finish executing. This implies that we can enter a deadlock situation involving two or more timer callbacks executing in parallel and attempting to cancel one another. Note that we avoid incrementing the cancelling counter for the target timer (the one being cancelled) if bpf_timer_cancel is not invoked from a callback, to avoid spurious errors. The whole point of detecting cur->cancelling and returning -EDEADLK is to not enter a busy wait loop (which may or may not lead to a lockup). This does not apply in case the caller is in a non-callback context, the other side can continue to cancel as it sees fit without running into errors. Background on prior attempts: Earlier versions of this patch used a bool 'cancelling' bit and used the following pattern under timer->lock to publish cancellation status. lock(t->lock); t->cancelling = true; mb(); if (cur->cancelling) return -EDEADLK; unlock(t->lock); hrtimer_cancel(t->timer); t->cancelling = false; The store outside the critical section could overwrite a parallel requests t->cancelling assignment to true, to ensure the parallely executing callback observes its cancellation status. It would be necessary to clear this cancelling bit once hrtimer_cancel is done, but lack of serialization introduced races. Another option was explored where bpf_timer_start would clear the bit when (re)starting the timer under timer->lock. This would ensure serialized access to the cancelling bit, but may allow it to be cleared before in-flight hrtimer_cancel has finished executing, such that lockups can occur again. Thus, we choose an atomic counter to keep track of all outstanding cancellation requests and use it to prevent lockups in case callbacks attempt to cancel each other while executing in parallel.Show less

In the Linux kernel, the following vulnerability has been resolved: i2c: pnx: Fix potential deadlock warning from del_timer_sync() call in isr When del_timer_sync() is called in an interrupt context it throws a warning because of potential deadlock. The timer is used only to exit from wait_for_completion() after a timeout so replacing the call with wait_for_completion_timeout() allows to remove the problematic timer and its related functions altogether.Show less

In the Linux kernel, the following vulnerability has been resolved: riscv: kexec: Avoid deadlock in kexec crash path If the kexec crash code is called in the interrupt context, the machine_kexec_mask_interrupts() function will trigger a deadlock while trying to acquire the irqdesc spinlock and then deactivate irqchip in irq_set_irqchip_state() function. Unlike arm64, riscv only requires irq_eoi handler to complete EOI and keeping irq_set_irqchip_state() will only leave this possible deadlock without any use. So we simply remove it.Show less

In the Linux kernel, the following vulnerability has been resolved: wifi: cfg80211: restrict NL80211_ATTR_TXQ_QUANTUM values syzbot is able to trigger softlockups, setting NL80211_ATTR_TXQ_QUANTUM to 2^31. We had a similar issue in sch_fq, fixed with commit d9e15a273306 ("pkt_sched: fq: do not accept silly TCA_FQ_QUANTUM") watchdog: BUG: soft lockup - CPU#1 stuck for 26s! [kworker/1:0:24] Modules linked in: irq event stamp: 131135 hardirqs last enabled at (131134): [<ffff80008ae8778c>] __exit_to_kernel_mode arch/arm64/kernel/entry-common.c:85 [inline] hardirqs last enabled at (131134): [<ffff80008ae8778c>] exit_to_kernel_mode+0xdc/0x10c arch/arm64/kernel/entry-common.c:95 hardirqs last disabled at (131135): [<ffff80008ae85378>] __el1_irq arch/arm64/kernel/entry-common.c:533 [inline] hardirqs last disabled at (131135): [<ffff80008ae85378>] el1_interrupt+0x24/0x68 arch/arm64/kernel/entry-common.c:551 softirqs last enabled at (125892): [<ffff80008907e82c>] neigh_hh_init net/core/neighbour.c:1538 [inline] softirqs last enabled at (125892): [<ffff80008907e82c>] neigh_resolve_output+0x268/0x658 net/core/neighbour.c:1553 softirqs last disabled at (125896): [<ffff80008904166c>] local_bh_disable+0x10/0x34 include/linux/bottom_half.h:19 CPU: 1 PID: 24 Comm: kworker/1:0 Not tainted 6.9.0-rc7-syzkaller-gfda5695d692c #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024 Workqueue: mld mld_ifc_work pstate: 80400005 (Nzcv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--) pc : __list_del include/linux/list.h:195 [inline] pc : __list_del_entry include/linux/list.h:218 [inline] pc : list_move_tail include/linux/list.h:310 [inline] pc : fq_tin_dequeue include/net/fq_impl.h:112 [inline] pc : ieee80211_tx_dequeue+0x6b8/0x3b4c net/mac80211/tx.c:3854 lr : __list_del_entry include/linux/list.h:218 [inline] lr : list_move_tail include/linux/list.h:310 [inline] lr : fq_tin_dequeue include/net/fq_impl.h:112 [inline] lr : ieee80211_tx_dequeue+0x67c/0x3b4c net/mac80211/tx.c:3854 sp : ffff800093d36700 x29: ffff800093d36a60 x28: ffff800093d36960 x27: dfff800000000000 x26: ffff0000d800ad50 x25: ffff0000d800abe0 x24: ffff0000d800abf0 x23: ffff0000e0032468 x22: ffff0000e00324d4 x21: ffff0000d800abf0 x20: ffff0000d800abf8 x19: ffff0000d800abf0 x18: ffff800093d363c0 x17: 000000000000d476 x16: ffff8000805519dc x15: ffff7000127a6cc8 x14: 1ffff000127a6cc8 x13: 0000000000000004 x12: ffffffffffffffff x11: ffff7000127a6cc8 x10: 0000000000ff0100 x9 : 0000000000000000 x8 : 0000000000000000 x7 : 0000000000000000 x6 : 0000000000000000 x5 : ffff80009287aa08 x4 : 0000000000000008 x3 : ffff80008034c7fc x2 : ffff0000e0032468 x1 : 00000000da0e46b8 x0 : ffff0000e0032470 Call trace: __list_del include/linux/list.h:195 [inline] __list_del_entry include/linux/list.h:218 [inline] list_move_tail include/linux/list.h:310 [inline] fq_tin_dequeue include/net/fq_impl.h:112 [inline] ieee80211_tx_dequeue+0x6b8/0x3b4c net/mac80211/tx.c:3854 wake_tx_push_queue net/mac80211/util.c:294 [inline] ieee80211_handle_wake_tx_queue+0x118/0x274 net/mac80211/util.c:315 drv_wake_tx_queue net/mac80211/driver-ops.h:1350 [inline] schedule_and_wake_txq net/mac80211/driver-ops.h:1357 [inline] ieee80211_queue_skb+0x18e8/0x2244 net/mac80211/tx.c:1664 ieee80211_tx+0x260/0x400 net/mac80211/tx.c:1966 ieee80211_xmit+0x278/0x354 net/mac80211/tx.c:2062 __ieee80211_subif_start_xmit+0xab8/0x122c net/mac80211/tx.c:4338 ieee80211_subif_start_xmit+0xe0/0x438 net/mac80211/tx.c:4532 __netdev_start_xmit include/linux/netdevice.h:4903 [inline] netdev_start_xmit include/linux/netdevice.h:4917 [inline] xmit_one net/core/dev.c:3531 [inline] dev_hard_start_xmit+0x27c/0x938 net/core/dev.c:3547 __dev_queue_xmit+0x1678/0x33fc net/core/dev.c:4341 dev_queue_xmit include/linux/netdevice.h:3091 [inline] neigh_resolve_output+0x558/0x658 net/core/neighbour.c:1563 neigh_output include/net/neighbour.h:542 [inline] ip6_fini ---truncated---Show less

In the Linux kernel, the following vulnerability has been resolved: pinctrl: fix deadlock in create_pinctrl() when handling -EPROBE_DEFER In create_pinctrl(), pinctrl_maps_mutex is acquired before calling add_setting(). If add_setting() returns -EPROBE_DEFER, create_pinctrl() calls pinctrl_free(). However, pinctrl_free() attempts to acquire pinctrl_maps_mutex, which is already held by create_pinctrl(), leading to a potential deadlock. This patch resolves the issue by releasing pinctrl_maps_mutex before calling pinctrl_free(), preventing the deadlock. This bug was discovered and resolved using Coverity Static Analysis Security Testing (SAST) by Synopsys, Inc.Show less

In the Linux kernel, the following vulnerability has been resolved: usb: dwc3: core: remove lock of otg mode during gadget suspend/resume to avoid deadlock When config CONFIG_USB_DWC3_DUAL_ROLE is selected, and trigger system to enter suspend status with below command: echo mem > /sys/power/state There will be a deadlock issue occurring. Detailed invoking path as below: dwc3_suspend_common() spin_lock_irqsave(&dwc->lock, flags); <-- 1st dwc3_gadget_suspend(dwc); dwc3_gadget_soft_disconnect(dwc); spin_lock_irqsave(&dwc->lock, flags); <-- 2nd This issue is exposed by commit c7ebd8149ee5 ("usb: dwc3: gadget: Fix NULL pointer dereference in dwc3_gadget_suspend") that removes the code of checking whether dwc->gadget_driver is NULL or not. It causes the following code is executed and deadlock occurs when trying to get the spinlock. In fact, the root cause is the commit 5265397f9442("usb: dwc3: Remove DWC3 locking during gadget suspend/resume") that forgot to remove the lock of otg mode. So, remove the redundant lock of otg mode during gadget suspend/resume.Show less

In the Linux kernel, the following vulnerability has been resolved: io_uring: fix possible deadlock in io_register_iowq_max_workers() The io_register_iowq_max_workers() function calls io_put_sq_data(), which acquires the sqd->lock without releasing the uring_lock. Similar to the commit 009ad9f0c6ee ("io_uring: drop ctx->uring_lock before acquiring sqd->lock"), this can lead to a potential deadlock situation. To resolve this issue, the uring_lock is released before calling io_put_sq_data(), and then it is re-acquired after the function call. This change ensures that the locks are acquired in the correct order, preventing the possibility of a deadlock.Show less

In the Linux kernel, the following vulnerability has been resolved: Bluetooth: hci_core: cancel all works upon hci_unregister_dev() syzbot is reporting that calling hci_release_dev() from hci_error_reset() due to hci_dev_put() from hci_error_reset() can cause deadlock at destroy_workqueue(), for hci_error_reset() is called from hdev->req_workqueue which destroy_workqueue() needs to flush. We need to make sure that hdev->{rx_work,cmd_work,tx_work} which are queued into hdev->workqueue and hdev->{power_on,error_reset} which are queued into hdev->req_workqueue are no longer running by the moment destroy_workqueue(hdev->workqueue); destroy_workqueue(hdev->req_workqueue); are called from hci_release_dev(). Call cancel_work_sync() on these work items from hci_unregister_dev() as soon as hdev->list is removed from hci_dev_list.Show less

In the Linux kernel, the following vulnerability has been resolved: net: ks8851: Fix deadlock with the SPI chip variant When SMP is enabled and spinlocks are actually functional then there is a deadlock with the 'statelock' spinlock between ks8851_start_xmit_spi and ks8851_irq: watchdog: BUG: soft lockup - CPU#0 stuck for 27s! call trace: queued_spin_lock_slowpath+0x100/0x284 do_raw_spin_lock+0x34/0x44 ks8851_start_xmit_spi+0x30/0xb8 ks8851_start_xmit+0x14/0x20 netdev_start_xmit+0x40/0x6c dev_hard_start_xmit+0x6c/0xbc sch_direct_xmit+0xa4/0x22c __qdisc_run+0x138/0x3fc qdisc_run+0x24/0x3c net_tx_action+0xf8/0x130 handle_softirqs+0x1ac/0x1f0 __do_softirq+0x14/0x20 ____do_softirq+0x10/0x1c call_on_irq_stack+0x3c/0x58 do_softirq_own_stack+0x1c/0x28 __irq_exit_rcu+0x54/0x9c irq_exit_rcu+0x10/0x1c el1_interrupt+0x38/0x50 el1h_64_irq_handler+0x18/0x24 el1h_64_irq+0x64/0x68 __netif_schedule+0x6c/0x80 netif_tx_wake_queue+0x38/0x48 ks8851_irq+0xb8/0x2c8 irq_thread_fn+0x2c/0x74 irq_thread+0x10c/0x1b0 kthread+0xc8/0xd8 ret_from_fork+0x10/0x20 This issue has not been identified earlier because tests were done on a device with SMP disabled and so spinlocks were actually NOPs. Now use spin_(un)lock_bh for TX queue related locking to avoid execution of softirq work synchronously that would lead to a deadlock.Show less

In the Linux kernel, the following vulnerability has been resolved: ice: Fix race condition during interface enslave Commit 5dbbbd01cbba83 ("ice: Avoid RTNL lock when re-creating auxiliary device") changes a process of re-creation of aux device so ice_plug_aux_dev() is called from ice_service_task() context. This unfortunately opens a race window that can result in dead-lock when interface has left LAG and immediately enters LAG again. Reproducer: ``` #!/bin/sh ip link add lag0 type bond mode 1 miimon 100 ip link set lag0 for n in {1..10}; do echo Cycle: $n ip link set ens7f0 master lag0 sleep 1 ip link set ens7f0 nomaster done ``` This results in: [20976.208697] Workqueue: ice ice_service_task [ice] [20976.213422] Call Trace: [20976.215871] __schedule+0x2d1/0x830 [20976.219364] schedule+0x35/0xa0 [20976.222510] schedule_preempt_disabled+0xa/0x10 [20976.227043] __mutex_lock.isra.7+0x310/0x420 [20976.235071] enum_all_gids_of_dev_cb+0x1c/0x100 [ib_core] [20976.251215] ib_enum_roce_netdev+0xa4/0xe0 [ib_core] [20976.256192] ib_cache_setup_one+0x33/0xa0 [ib_core] [20976.261079] ib_register_device+0x40d/0x580 [ib_core] [20976.266139] irdma_ib_register_device+0x129/0x250 [irdma] [20976.281409] irdma_probe+0x2c1/0x360 [irdma] [20976.285691] auxiliary_bus_probe+0x45/0x70 [20976.289790] really_probe+0x1f2/0x480 [20976.298509] driver_probe_device+0x49/0xc0 [20976.302609] bus_for_each_drv+0x79/0xc0 [20976.306448] __device_attach+0xdc/0x160 [20976.310286] bus_probe_device+0x9d/0xb0 [20976.314128] device_add+0x43c/0x890 [20976.321287] __auxiliary_device_add+0x43/0x60 [20976.325644] ice_plug_aux_dev+0xb2/0x100 [ice] [20976.330109] ice_service_task+0xd0c/0xed0 [ice] [20976.342591] process_one_work+0x1a7/0x360 [20976.350536] worker_thread+0x30/0x390 [20976.358128] kthread+0x10a/0x120 [20976.365547] ret_from_fork+0x1f/0x40 ... [20976.438030] task:ip state:D stack: 0 pid:213658 ppid:213627 flags:0x00004084 [20976.446469] Call Trace: [20976.448921] __schedule+0x2d1/0x830 [20976.452414] schedule+0x35/0xa0 [20976.455559] schedule_preempt_disabled+0xa/0x10 [20976.460090] __mutex_lock.isra.7+0x310/0x420 [20976.464364] device_del+0x36/0x3c0 [20976.467772] ice_unplug_aux_dev+0x1a/0x40 [ice] [20976.472313] ice_lag_event_handler+0x2a2/0x520 [ice] [20976.477288] notifier_call_chain+0x47/0x70 [20976.481386] __netdev_upper_dev_link+0x18b/0x280 [20976.489845] bond_enslave+0xe05/0x1790 [bonding] [20976.494475] do_setlink+0x336/0xf50 [20976.502517] __rtnl_newlink+0x529/0x8b0 [20976.543441] rtnl_newlink+0x43/0x60 [20976.546934] rtnetlink_rcv_msg+0x2b1/0x360 [20976.559238] netlink_rcv_skb+0x4c/0x120 [20976.563079] netlink_unicast+0x196/0x230 [20976.567005] netlink_sendmsg+0x204/0x3d0 [20976.570930] sock_sendmsg+0x4c/0x50 [20976.574423] ____sys_sendmsg+0x1eb/0x250 [20976.586807] ___sys_sendmsg+0x7c/0xc0 [20976.606353] __sys_sendmsg+0x57/0xa0 [20976.609930] do_syscall_64+0x5b/0x1a0 [20976.613598] entry_SYSCALL_64_after_hwframe+0x65/0xca 1. Command 'ip link ... set nomaster' causes that ice_plug_aux_dev() is called from ice_service_task() context, aux device is created and associated device->lock is taken. 2. Command 'ip link ... set master...' calls ice's notifier under RTNL lock and that notifier calls ice_unplug_aux_dev(). That function tries to take aux device->lock but this is already taken by ice_plug_aux_dev() in step 1 3. Later ice_plug_aux_dev() tries to take RTNL lock but this is already taken in step 2 4. Dead-lock The patch fixes this issue by following changes: - Bit ICE_FLAG_PLUG_AUX_DEV is kept to be set during ice_plug_aux_dev() call in ice_service_task() - The bit is checked in ice_clear_rdma_cap() and only if it is not set then ice_unplug_aux_dev() is called. If it is set (in other words plugging of aux device was requested and ice_plug_aux_dev() is potentially running) then the function only clears the ---truncated---Show less

In the Linux kernel, the following vulnerability has been resolved: drm/vc4: Fix deadlock on DSI device attach error DSI device attach to DSI host will be done with host device's lock held. Un-registering host in "device attach" error path (ex: probe retry) will result in deadlock with below call trace and non operational DSI display. Startup Call trace: [ 35.043036] rt_mutex_slowlock.constprop.21+0x184/0x1b8 [ 35.043048] mutex_lock_nested+0x7c/0xc8 [ 35.043060] device_del+0x4c/0x3e8 [ 35.043075] device_unregister+0x20/0x40 [ 35.043082] mipi_dsi_remove_device_fn+0x18/0x28 [ 35.043093] device_for_each_child+0x68/0xb0 [ 35.043105] mipi_dsi_host_unregister+0x40/0x90 [ 35.043115] vc4_dsi_host_attach+0xf0/0x120 [vc4] [ 35.043199] mipi_dsi_attach+0x30/0x48 [ 35.043209] tc358762_probe+0x128/0x164 [tc358762] [ 35.043225] mipi_dsi_drv_probe+0x28/0x38 [ 35.043234] really_probe+0xc0/0x318 [ 35.043244] __driver_probe_device+0x80/0xe8 [ 35.043254] driver_probe_device+0xb8/0x118 [ 35.043263] __device_attach_driver+0x98/0xe8 [ 35.043273] bus_for_each_drv+0x84/0xd8 [ 35.043281] __device_attach+0xf0/0x150 [ 35.043290] device_initial_probe+0x1c/0x28 [ 35.043300] bus_probe_device+0xa4/0xb0 [ 35.043308] deferred_probe_work_func+0xa0/0xe0 [ 35.043318] process_one_work+0x254/0x700 [ 35.043330] worker_thread+0x4c/0x448 [ 35.043339] kthread+0x19c/0x1a8 [ 35.043348] ret_from_fork+0x10/0x20 Shutdown Call trace: [ 365.565417] Call trace: [ 365.565423] __switch_to+0x148/0x200 [ 365.565452] __schedule+0x340/0x9c8 [ 365.565467] schedule+0x48/0x110 [ 365.565479] schedule_timeout+0x3b0/0x448 [ 365.565496] wait_for_completion+0xac/0x138 [ 365.565509] __flush_work+0x218/0x4e0 [ 365.565523] flush_work+0x1c/0x28 [ 365.565536] wait_for_device_probe+0x68/0x158 [ 365.565550] device_shutdown+0x24/0x348 [ 365.565561] kernel_restart_prepare+0x40/0x50 [ 365.565578] kernel_restart+0x20/0x70 [ 365.565591] __do_sys_reboot+0x10c/0x220 [ 365.565605] __arm64_sys_reboot+0x2c/0x38 [ 365.565619] invoke_syscall+0x4c/0x110 [ 365.565634] el0_svc_common.constprop.3+0xfc/0x120 [ 365.565648] do_el0_svc+0x2c/0x90 [ 365.565661] el0_svc+0x4c/0xf0 [ 365.565671] el0t_64_sync_handler+0x90/0xb8 [ 365.565682] el0t_64_sync+0x180/0x184Show less

In the Linux kernel, the following vulnerability has been resolved: ipmr,ip6mr: acquire RTNL before calling ip[6]mr_free_table() on failure path ip[6]mr_free_table() can only be called under RTNL lock. RTNL: assertion failed at net/core/dev.c (10367) WARNING: CPU: 1 PID: 5890 at net/core/dev.c:10367 unregister_netdevice_many+0x1246/0x1850 net/core/dev.c:10367 Modules linked in: CPU: 1 PID: 5890 Comm: syz-executor.2 Not tainted 5.16.0-syzkaller-11627-g422ee58dc0ef #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:unregister_netdevice_many+0x1246/0x1850 net/core/dev.c:10367 Code: 0f 85 9b ee ff ff e8 69 07 4b fa ba 7f 28 00 00 48 c7 c6 00 90 ae 8a 48 c7 c7 40 90 ae 8a c6 05 6d b1 51 06 01 e8 8c 90 d8 01 <0f> 0b e9 70 ee ff ff e8 3e 07 4b fa 4c 89 e7 e8 86 2a 59 fa e9 ee RSP: 0018:ffffc900046ff6e0 EFLAGS: 00010286 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000 RDX: ffff888050f51d00 RSI: ffffffff815fa008 RDI: fffff520008dfece RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: ffffffff815f3d6e R11: 0000000000000000 R12: 00000000fffffff4 R13: dffffc0000000000 R14: ffffc900046ff750 R15: ffff88807b7dc000 FS: 00007f4ab736e700(0000) GS:ffff8880b9d00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fee0b4f8990 CR3: 000000001e7d2000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: <TASK> mroute_clean_tables+0x244/0xb40 net/ipv6/ip6mr.c:1509 ip6mr_free_table net/ipv6/ip6mr.c:389 [inline] ip6mr_rules_init net/ipv6/ip6mr.c:246 [inline] ip6mr_net_init net/ipv6/ip6mr.c:1306 [inline] ip6mr_net_init+0x3f0/0x4e0 net/ipv6/ip6mr.c:1298 ops_init+0xaf/0x470 net/core/net_namespace.c:140 setup_net+0x54f/0xbb0 net/core/net_namespace.c:331 copy_net_ns+0x318/0x760 net/core/net_namespace.c:475 create_new_namespaces+0x3f6/0xb20 kernel/nsproxy.c:110 copy_namespaces+0x391/0x450 kernel/nsproxy.c:178 copy_process+0x2e0c/0x7300 kernel/fork.c:2167 kernel_clone+0xe7/0xab0 kernel/fork.c:2555 __do_sys_clone+0xc8/0x110 kernel/fork.c:2672 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7f4ab89f9059 Code: Unable to access opcode bytes at RIP 0x7f4ab89f902f. RSP: 002b:00007f4ab736e118 EFLAGS: 00000206 ORIG_RAX: 0000000000000038 RAX: ffffffffffffffda RBX: 00007f4ab8b0bf60 RCX: 00007f4ab89f9059 RDX: 0000000020000280 RSI: 0000000020000270 RDI: 0000000040200000 RBP: 00007f4ab8a5308d R08: 0000000020000300 R09: 0000000020000300 R10: 00000000200002c0 R11: 0000000000000206 R12: 0000000000000000 R13: 00007ffc3977cc1f R14: 00007f4ab736e300 R15: 0000000000022000 </TASK>Show less

In the Linux kernel, the following vulnerability has been resolved: mm: vmscan: remove deadlock due to throttling failing to make progress A soft lockup bug in kcompactd was reported in a private bugzilla with the following visible in dmesg; watchdog: BUG: soft lockup - CPU#33 stuck for 26s! [kcompactd0:479] watchdog: BUG: soft lockup - CPU#33 stuck for 52s! [kcompactd0:479] watchdog: BUG: soft lockup - CPU#33 stuck for 78s! [kcompactd0:479] watchdog: BUG: soft lockup - CPU#33 stuck for 104s! [kcompactd0:479] The machine had 256G of RAM with no swap and an earlier failed allocation indicated that node 0 where kcompactd was run was potentially unreclaimable; Node 0 active_anon:29355112kB inactive_anon:2913528kB active_file:0kB inactive_file:0kB unevictable:64kB isolated(anon):0kB isolated(file):0kB mapped:8kB dirty:0kB writeback:0kB shmem:26780kB shmem_thp: 0kB shmem_pmdmapped: 0kB anon_thp: 23480320kB writeback_tmp:0kB kernel_stack:2272kB pagetables:24500kB all_unreclaimable? yes Vlastimil Babka investigated a crash dump and found that a task migrating pages was trying to drain PCP lists; PID: 52922 TASK: ffff969f820e5000 CPU: 19 COMMAND: "kworker/u128:3" Call Trace: __schedule schedule schedule_timeout wait_for_completion __flush_work __drain_all_pages __alloc_pages_slowpath.constprop.114 __alloc_pages alloc_migration_target migrate_pages migrate_to_node do_migrate_pages cpuset_migrate_mm_workfn process_one_work worker_thread kthread ret_from_fork This failure is specific to CONFIG_PREEMPT=n builds. The root of the problem is that kcompact0 is not rescheduling on a CPU while a task that has isolated a large number of the pages from the LRU is waiting on kcompact0 to reschedule so the pages can be released. While shrink_inactive_list() only loops once around too_many_isolated, reclaim can continue without rescheduling if sc->skipped_deactivate == 1 which could happen if there was no file LRU and the inactive anon list was not low.Show less

In the Linux kernel, the following vulnerability has been resolved: ipv6: mcast: use rcu-safe version of ipv6_get_lladdr() Some time ago 8965779d2c0e ("ipv6,mcast: always hold idev->lock before mca_lock") switched ipv6_get_lladdr() to __ipv6_get_lladdr(), which is rcu-unsafe version. That was OK, because idev->lock was held for these codepaths. In 88e2ca308094 ("mld: convert ifmcaddr6 to RCU") these external locks were removed, so we probably need to restore the original rcu-safe call. Otherwise, we occasionally get a machine crashed/stalled with the following in dmesg: [ 3405.966610][T230589] general protection fault, probably for non-canonical address 0xdead00000000008c: 0000 [#1] SMP NOPTI [ 3405.982083][T230589] CPU: 44 PID: 230589 Comm: kworker/44:3 Tainted: G O 5.15.19-cloudflare-2022.2.1 #1 [ 3405.998061][T230589] Hardware name: SUPA-COOL-SERV [ 3406.009552][T230589] Workqueue: mld mld_ifc_work [ 3406.017224][T230589] RIP: 0010:__ipv6_get_lladdr+0x34/0x60 [ 3406.025780][T230589] Code: 57 10 48 83 c7 08 48 89 e5 48 39 d7 74 3e 48 8d 82 38 ff ff ff eb 13 48 8b 90 d0 00 00 00 48 8d 82 38 ff ff ff 48 39 d7 74 22 <66> 83 78 32 20 77 1b 75 e4 89 ca 23 50 2c 75 dd 48 8b 50 08 48 8b [ 3406.055748][T230589] RSP: 0018:ffff94e4b3fc3d10 EFLAGS: 00010202 [ 3406.065617][T230589] RAX: dead00000000005a RBX: ffff94e4b3fc3d30 RCX: 0000000000000040 [ 3406.077477][T230589] RDX: dead000000000122 RSI: ffff94e4b3fc3d30 RDI: ffff8c3a31431008 [ 3406.089389][T230589] RBP: ffff94e4b3fc3d10 R08: 0000000000000000 R09: 0000000000000000 [ 3406.101445][T230589] R10: ffff8c3a31430000 R11: 000000000000000b R12: ffff8c2c37887100 [ 3406.113553][T230589] R13: ffff8c3a39537000 R14: 00000000000005dc R15: ffff8c3a31431000 [ 3406.125730][T230589] FS: 0000000000000000(0000) GS:ffff8c3b9fc80000(0000) knlGS:0000000000000000 [ 3406.138992][T230589] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 3406.149895][T230589] CR2: 00007f0dfea1db60 CR3: 000000387b5f2000 CR4: 0000000000350ee0 [ 3406.162421][T230589] Call Trace: [ 3406.170235][T230589] <TASK> [ 3406.177736][T230589] mld_newpack+0xfe/0x1a0 [ 3406.186686][T230589] add_grhead+0x87/0xa0 [ 3406.195498][T230589] add_grec+0x485/0x4e0 [ 3406.204310][T230589] ? newidle_balance+0x126/0x3f0 [ 3406.214024][T230589] mld_ifc_work+0x15d/0x450 [ 3406.223279][T230589] process_one_work+0x1e6/0x380 [ 3406.232982][T230589] worker_thread+0x50/0x3a0 [ 3406.242371][T230589] ? rescuer_thread+0x360/0x360 [ 3406.252175][T230589] kthread+0x127/0x150 [ 3406.261197][T230589] ? set_kthread_struct+0x40/0x40 [ 3406.271287][T230589] ret_from_fork+0x22/0x30 [ 3406.280812][T230589] </TASK> [ 3406.288937][T230589] Modules linked in: ... [last unloaded: kheaders] [ 3406.476714][T230589] ---[ end trace 3525a7655f2f3b9e ]---Show less

In the Linux kernel, the following vulnerability has been resolved: scsi: ufs: Fix a deadlock in the error handler The following deadlock has been observed on a test setup: - All tags allocated - The SCSI error handler calls ufshcd_eh_host_reset_handler() - ufshcd_eh_host_reset_handler() queues work that calls ufshcd_err_handler() - ufshcd_err_handler() locks up as follows: Workqueue: ufs_eh_wq_0 ufshcd_err_handler.cfi_jt Call trace: __switch_to+0x298/0x5d8 __schedule+0x6cc/0xa94 schedule+0x12c/0x298 blk_mq_get_tag+0x210/0x480 __blk_mq_alloc_request+0x1c8/0x284 blk_get_request+0x74/0x134 ufshcd_exec_dev_cmd+0x68/0x640 ufshcd_verify_dev_init+0x68/0x35c ufshcd_probe_hba+0x12c/0x1cb8 ufshcd_host_reset_and_restore+0x88/0x254 ufshcd_reset_and_restore+0xd0/0x354 ufshcd_err_handler+0x408/0xc58 process_one_work+0x24c/0x66c worker_thread+0x3e8/0xa4c kthread+0x150/0x1b4 ret_from_fork+0x10/0x30 Fix this lockup by making ufshcd_exec_dev_cmd() allocate a reserved request.Show less