Vulnerabilities

In the Linux kernel, the following vulnerability has been resolved:<br /> <br /> bnxt_en: Fix RX consumer index logic in the error path.<br /> <br /> In bnxt_rx_pkt(), the RX buffers are expected to complete in order.<br /> If the RX consumer index indicates an out of order buffer completion,<br /> it means we are hitting a hardware bug and the driver will abort all<br /> remaining RX packets and reset the RX ring. The RX consumer index<br /> that we pass to bnxt_discard_rx() is not correct. We should be<br /> passing the current index (tmp_raw_cons) instead of the old index<br /> (raw_cons). This bug can cause us to be at the wrong index when<br /> trying to abort the next RX packet. It can crash like this:<br /> <br /> #0 [ffff9bbcdf5c39a8] machine_kexec at ffffffff9b05e007<br /> #1 [ffff9bbcdf5c3a00] __crash_kexec at ffffffff9b111232<br /> #2 [ffff9bbcdf5c3ad0] panic at ffffffff9b07d61e<br /> #3 [ffff9bbcdf5c3b50] oops_end at ffffffff9b030978<br /> #4 [ffff9bbcdf5c3b78] no_context at ffffffff9b06aaf0<br /> #5 [ffff9bbcdf5c3bd8] __bad_area_nosemaphore at ffffffff9b06ae2e<br /> #6 [ffff9bbcdf5c3c28] bad_area_nosemaphore at ffffffff9b06af24<br /> #7 [ffff9bbcdf5c3c38] __do_page_fault at ffffffff9b06b67e<br /> #8 [ffff9bbcdf5c3cb0] do_page_fault at ffffffff9b06bb12<br /> #9 [ffff9bbcdf5c3ce0] page_fault at ffffffff9bc015c5<br /> [exception RIP: bnxt_rx_pkt+237]<br /> RIP: ffffffffc0259cdd RSP: ffff9bbcdf5c3d98 RFLAGS: 00010213<br /> RAX: 000000005dd8097f RBX: ffff9ba4cb11b7e0 RCX: ffffa923cf6e9000<br /> RDX: 0000000000000fff RSI: 0000000000000627 RDI: 0000000000001000<br /> RBP: ffff9bbcdf5c3e60 R8: 0000000000420003 R9: 000000000000020d<br /> R10: ffffa923cf6ec138 R11: ffff9bbcdf5c3e83 R12: ffff9ba4d6f928c0<br /> R13: ffff9ba4cac28080 R14: ffff9ba4cb11b7f0 R15: ffff9ba4d5a30000<br /> ORIG_RAX: ffffffffffffffff CS: 0010 SS: 0018

In the Linux kernel, the following vulnerability has been resolved:<br /> <br /> ath10k: Fix a use after free in ath10k_htc_send_bundle<br /> <br /> In ath10k_htc_send_bundle, the bundle_skb could be freed by<br /> dev_kfree_skb_any(bundle_skb). But the bundle_skb is used later<br /> by bundle_skb-&gt;len.<br /> <br /> As skb_len = bundle_skb-&gt;len, my patch replaces bundle_skb-&gt;len to<br /> skb_len after the bundle_skb was freed.

In the Linux kernel, the following vulnerability has been resolved:<br /> <br /> netfilter: nftables: Fix a memleak from userdata error path in new objects<br /> <br /> Release object name if userdata allocation fails.

In the Linux kernel, the following vulnerability has been resolved:<br /> <br /> arm64: entry: always set GIC_PRIO_PSR_I_SET during entry<br /> <br /> Zenghui reports that booting a kernel with "irqchip.gicv3_pseudo_nmi=1"<br /> on the command line hits a warning during kernel entry, due to the way<br /> we manipulate the PMR.<br /> <br /> Early in the entry sequence, we call lockdep_hardirqs_off() to inform<br /> lockdep that interrupts have been masked (as the HW sets DAIF wqhen<br /> entering an exception). Architecturally PMR_EL1 is not affected by<br /> exception entry, and we don&amp;#39;t set GIC_PRIO_PSR_I_SET in the PMR early in<br /> the exception entry sequence, so early in exception entry the PMR can<br /> indicate that interrupts are unmasked even though they are masked by<br /> DAIF.<br /> <br /> If DEBUG_LOCKDEP is selected, lockdep_hardirqs_off() will check that<br /> interrupts are masked, before we set GIC_PRIO_PSR_I_SET in any of the<br /> exception entry paths, and hence lockdep_hardirqs_off() will WARN() that<br /> something is amiss.<br /> <br /> We can avoid this by consistently setting GIC_PRIO_PSR_I_SET during<br /> exception entry so that kernel code sees a consistent environment. We<br /> must also update local_daif_inherit() to undo this, as currently only<br /> touches DAIF. For other paths, local_daif_restore() will update both<br /> DAIF and the PMR. With this done, we can remove the existing special<br /> cases which set this later in the entry code.<br /> <br /> We always use (GIC_PRIO_IRQON | GIC_PRIO_PSR_I_SET) for consistency with<br /> local_daif_save(), as this will warn if it ever encounters<br /> (GIC_PRIO_IRQOFF | GIC_PRIO_PSR_I_SET), and never sets this itself. This<br /> matches the gic_prio_kentry_setup that we have to retain for<br /> ret_to_user.<br /> <br /> The original splat from Zenghui&amp;#39;s report was:<br /> <br /> | DEBUG_LOCKS_WARN_ON(!irqs_disabled())<br /> | WARNING: CPU: 3 PID: 125 at kernel/locking/lockdep.c:4258 lockdep_hardirqs_off+0xd4/0xe8<br /> | Modules linked in:<br /> | CPU: 3 PID: 125 Comm: modprobe Tainted: G W 5.12.0-rc8+ #463<br /> | Hardware name: QEMU KVM Virtual Machine, BIOS 0.0.0 02/06/2015<br /> | pstate: 604003c5 (nZCv DAIF +PAN -UAO -TCO BTYPE=--)<br /> | pc : lockdep_hardirqs_off+0xd4/0xe8<br /> | lr : lockdep_hardirqs_off+0xd4/0xe8<br /> | sp : ffff80002a39bad0<br /> | pmr_save: 000000e0<br /> | x29: ffff80002a39bad0 x28: ffff0000de214bc0<br /> | x27: ffff0000de1c0400 x26: 000000000049b328<br /> | x25: 0000000000406f30 x24: ffff0000de1c00a0<br /> | x23: 0000000020400005 x22: ffff8000105f747c<br /> | x21: 0000000096000044 x20: 0000000000498ef9<br /> | x19: ffff80002a39bc88 x18: ffffffffffffffff<br /> | x17: 0000000000000000 x16: ffff800011c61eb0<br /> | x15: ffff800011700a88 x14: 0720072007200720<br /> | x13: 0720072007200720 x12: 0720072007200720<br /> | x11: 0720072007200720 x10: 0720072007200720<br /> | x9 : ffff80002a39bad0 x8 : ffff80002a39bad0<br /> | x7 : ffff8000119f0800 x6 : c0000000ffff7fff<br /> | x5 : ffff8000119f07a8 x4 : 0000000000000001<br /> | x3 : 9bcdab23f2432800 x2 : ffff800011730538<br /> | x1 : 9bcdab23f2432800 x0 : 0000000000000000<br /> | Call trace:<br /> | lockdep_hardirqs_off+0xd4/0xe8<br /> | enter_from_kernel_mode.isra.5+0x7c/0xa8<br /> | el1_abort+0x24/0x100<br /> | el1_sync_handler+0x80/0xd0<br /> | el1_sync+0x6c/0x100<br /> | __arch_clear_user+0xc/0x90<br /> | load_elf_binary+0x9fc/0x1450<br /> | bprm_execve+0x404/0x880<br /> | kernel_execve+0x180/0x188<br /> | call_usermodehelper_exec_async+0xdc/0x158<br /> | ret_from_fork+0x10/0x18

In the Linux kernel, the following vulnerability has been resolved:<br /> <br /> ethernet:enic: Fix a use after free bug in enic_hard_start_xmit<br /> <br /> In enic_hard_start_xmit, it calls enic_queue_wq_skb(). Inside<br /> enic_queue_wq_skb, if some error happens, the skb will be freed<br /> by dev_kfree_skb(skb). But the freed skb is still used in<br /> skb_tx_timestamp(skb).<br /> <br /> My patch makes enic_queue_wq_skb() return error and goto spin_unlock()<br /> incase of error. The solution is provided by Govind.<br /> See https://lkml.org/lkml/2021/4/30/961.

In the Linux kernel, the following vulnerability has been resolved:<br /> <br /> media: aspeed: fix clock handling logic<br /> <br /> Video engine uses eclk and vclk for its clock sources and its reset<br /> control is coupled with eclk so the current clock enabling sequence works<br /> like below.<br /> <br /> Enable eclk<br /> De-assert Video Engine reset<br /> 10ms delay<br /> Enable vclk<br /> <br /> It introduces improper reset on the Video Engine hardware and eventually<br /> the hardware generates unexpected DMA memory transfers that can corrupt<br /> memory region in random and sporadic patterns. This issue is observed<br /> very rarely on some specific AST2500 SoCs but it causes a critical<br /> kernel panic with making a various shape of signature so it&amp;#39;s extremely<br /> hard to debug. Moreover, the issue is observed even when the video<br /> engine is not actively used because udevd turns on the video engine<br /> hardware for a short time to make a query in every boot.<br /> <br /> To fix this issue, this commit changes the clock handling logic to make<br /> the reset de-assertion triggered after enabling both eclk and vclk. Also,<br /> it adds clk_unprepare call for a case when probe fails.<br /> <br /> clk: ast2600: fix reset settings for eclk and vclk<br /> Video engine reset setting should be coupled with eclk to match it<br /> with the setting for previous Aspeed SoCs which is defined in<br /> clk-aspeed.c since all Aspeed SoCs are sharing a single video engine<br /> driver. Also, reset bit 6 is defined as &amp;#39;Video Engine&amp;#39; reset in<br /> datasheet so it should be de-asserted when eclk is enabled. This<br /> commit fixes the setting.

In the Linux kernel, the following vulnerability has been resolved:<br /> <br /> drm/i915: Fix crash in auto_retire<br /> <br /> The retire logic uses the 2 lower bits of the pointer to the retire<br /> function to store flags. However, the auto_retire function is not<br /> guaranteed to be aligned to a multiple of 4, which causes crashes as<br /> we jump to the wrong address, for example like this:<br /> <br /> 2021-04-24T18:03:53.804300Z WARNING kernel: [ 516.876901] invalid opcode: 0000 [#1] PREEMPT SMP NOPTI<br /> 2021-04-24T18:03:53.804310Z WARNING kernel: [ 516.876906] CPU: 7 PID: 146 Comm: kworker/u16:6 Tainted: G U 5.4.105-13595-g3cd84167b2df #1<br /> 2021-04-24T18:03:53.804311Z WARNING kernel: [ 516.876907] Hardware name: Google Volteer2/Volteer2, BIOS Google_Volteer2.13672.76.0 02/22/2021<br /> 2021-04-24T18:03:53.804312Z WARNING kernel: [ 516.876911] Workqueue: events_unbound active_work<br /> 2021-04-24T18:03:53.804313Z WARNING kernel: [ 516.876914] RIP: 0010:auto_retire+0x1/0x20<br /> 2021-04-24T18:03:53.804314Z WARNING kernel: [ 516.876916] Code: e8 01 f2 ff ff eb 02 31 db 48 89 d8 5b 5d c3 0f 1f 44 00 00 55 48 89 e5 f0 ff 87 c8 00 00 00 0f 88 ab 47 4a 00 31 c0 5d c3 0f 44 00 00 55 48 89 e5 f0 ff 8f c8 00 00 00 0f 88 9a 47 4a 00 74<br /> 2021-04-24T18:03:53.804319Z WARNING kernel: [ 516.876918] RSP: 0018:ffff9b4d809fbe38 EFLAGS: 00010286<br /> 2021-04-24T18:03:53.804320Z WARNING kernel: [ 516.876919] RAX: 0000000000000007 RBX: ffff927915079600 RCX: 0000000000000007<br /> 2021-04-24T18:03:53.804320Z WARNING kernel: [ 516.876921] RDX: ffff9b4d809fbe40 RSI: 0000000000000286 RDI: ffff927915079600<br /> 2021-04-24T18:03:53.804321Z WARNING kernel: [ 516.876922] RBP: ffff9b4d809fbe68 R08: 8080808080808080 R09: fefefefefefefeff<br /> 2021-04-24T18:03:53.804321Z WARNING kernel: [ 516.876924] R10: 0000000000000010 R11: ffffffff92e44bd8 R12: ffff9279150796a0<br /> 2021-04-24T18:03:53.804322Z WARNING kernel: [ 516.876925] R13: ffff92791c368180 R14: ffff927915079640 R15: 000000001c867605<br /> 2021-04-24T18:03:53.804323Z WARNING kernel: [ 516.876926] FS: 0000000000000000(0000) GS:ffff92791ffc0000(0000) knlGS:0000000000000000<br /> 2021-04-24T18:03:53.804323Z WARNING kernel: [ 516.876928] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033<br /> 2021-04-24T18:03:53.804324Z WARNING kernel: [ 516.876929] CR2: 0000239514955000 CR3: 00000007f82da001 CR4: 0000000000760ee0<br /> 2021-04-24T18:03:53.804325Z WARNING kernel: [ 516.876930] PKRU: 55555554<br /> 2021-04-24T18:03:53.804325Z WARNING kernel: [ 516.876931] Call Trace:<br /> 2021-04-24T18:03:53.804326Z WARNING kernel: [ 516.876935] __active_retire+0x77/0xcf<br /> 2021-04-24T18:03:53.804326Z WARNING kernel: [ 516.876939] process_one_work+0x1da/0x394<br /> 2021-04-24T18:03:53.804327Z WARNING kernel: [ 516.876941] worker_thread+0x216/0x375<br /> 2021-04-24T18:03:53.804327Z WARNING kernel: [ 516.876944] kthread+0x147/0x156<br /> 2021-04-24T18:03:53.804335Z WARNING kernel: [ 516.876946] ? pr_cont_work+0x58/0x58<br /> 2021-04-24T18:03:53.804335Z WARNING kernel: [ 516.876948] ? kthread_blkcg+0x2e/0x2e<br /> 2021-04-24T18:03:53.804336Z WARNING kernel: [ 516.876950] ret_from_fork+0x1f/0x40<br /> 2021-04-24T18:03:53.804336Z WARNING kernel: [ 516.876952] Modules linked in: cdc_mbim cdc_ncm cdc_wdm xt_cgroup rfcomm cmac algif_hash algif_skcipher af_alg xt_MASQUERADE uinput snd_soc_rt5682_sdw snd_soc_rt5682 snd_soc_max98373_sdw snd_soc_max98373 snd_soc_rl6231 regmap_sdw snd_soc_sof_sdw snd_soc_hdac_hdmi snd_soc_dmic snd_hda_codec_hdmi snd_sof_pci snd_sof_intel_hda_common intel_ipu6_psys snd_sof_xtensa_dsp soundwire_intel soundwire_generic_allocation soundwire_cadence snd_sof_intel_hda snd_sof snd_soc_hdac_hda snd_soc_acpi_intel_match snd_soc_acpi snd_hda_ext_core soundwire_bus snd_hda_intel snd_intel_dspcfg snd_hda_codec snd_hwdep snd_hda_core intel_ipu6_isys videobuf2_dma_contig videobuf2_v4l2 videobuf2_common videobuf2_memops mei_hdcp intel_ipu6 ov2740 ov8856 at24 sx9310 dw9768 v4l2_fwnode cros_ec_typec intel_pmc_mux roles acpi_als typec fuse iio_trig_sysfs cros_ec_light_prox cros_ec_lid_angle cros_ec_sensors cros<br /> ---truncated---

In the Linux kernel, the following vulnerability has been resolved:<br /> <br /> KVM: VMX: Disable preemption when probing user return MSRs<br /> <br /> Disable preemption when probing a user return MSR via RDSMR/WRMSR. If<br /> the MSR holds a different value per logical CPU, the WRMSR could corrupt<br /> the host&amp;#39;s value if KVM is preempted between the RDMSR and WRMSR, and<br /> then rescheduled on a different CPU.<br /> <br /> Opportunistically land the helper in common x86, SVM will use the helper<br /> in a future commit.

In the Linux kernel, the following vulnerability has been resolved:<br /> <br /> KVM: nVMX: Always make an attempt to map eVMCS after migration<br /> <br /> When enlightened VMCS is in use and nested state is migrated with<br /> vmx_get_nested_state()/vmx_set_nested_state() KVM can&amp;#39;t map evmcs<br /> page right away: evmcs gpa is not &amp;#39;struct kvm_vmx_nested_state_hdr&amp;#39;<br /> and we can&amp;#39;t read it from VP assist page because userspace may decide<br /> to restore HV_X64_MSR_VP_ASSIST_PAGE after restoring nested state<br /> (and QEMU, for example, does exactly that). To make sure eVMCS is<br /> mapped /vmx_set_nested_state() raises KVM_REQ_GET_NESTED_STATE_PAGES<br /> request.<br /> <br /> Commit f2c7ef3ba955 ("KVM: nSVM: cancel KVM_REQ_GET_NESTED_STATE_PAGES<br /> on nested vmexit") added KVM_REQ_GET_NESTED_STATE_PAGES clearing to<br /> nested_vmx_vmexit() to make sure MSR permission bitmap is not switched<br /> when an immediate exit from L2 to L1 happens right after migration (caused<br /> by a pending event, for example). Unfortunately, in the exact same<br /> situation we still need to have eVMCS mapped so<br /> nested_sync_vmcs12_to_shadow() reflects changes in VMCS12 to eVMCS.<br /> <br /> As a band-aid, restore nested_get_evmcs_page() when clearing<br /> KVM_REQ_GET_NESTED_STATE_PAGES in nested_vmx_vmexit(). The &amp;#39;fix&amp;#39; is far<br /> from being ideal as we can&amp;#39;t easily propagate possible failures and even if<br /> we could, this is most likely already too late to do so. The whole<br /> &amp;#39;KVM_REQ_GET_NESTED_STATE_PAGES&amp;#39; idea for mapping eVMCS after migration<br /> seems to be fragile as we diverge too much from the &amp;#39;native&amp;#39; path when<br /> vmptr loading happens on vmx_set_nested_state().

In the Linux kernel, the following vulnerability has been resolved:<br /> <br /> iio: core: fix ioctl handlers removal<br /> <br /> Currently ioctl handlers are removed twice. For the first time during<br /> iio_device_unregister() then later on inside<br /> iio_device_unregister_eventset() and iio_buffers_free_sysfs_and_mask().<br /> Double free leads to kernel panic.<br /> <br /> Fix this by not touching ioctl handlers list directly but rather<br /> letting code responsible for registration call the matching cleanup<br /> routine itself.

In the Linux kernel, the following vulnerability has been resolved:<br /> <br /> usb: typec: ucsi: Retrieve all the PDOs instead of just the first 4<br /> <br /> commit 4dbc6a4ef06d ("usb: typec: ucsi: save power data objects<br /> in PD mode") introduced retrieval of the PDOs when connected to a<br /> PD-capable source. But only the first 4 PDOs are received since<br /> that is the maximum number that can be fetched at a time given the<br /> MESSAGE_IN length limitation (16 bytes). However, as per the PD spec<br /> a connected source may advertise up to a maximum of 7 PDOs.<br /> <br /> If such a source is connected it&amp;#39;s possible the PPM could have<br /> negotiated a power contract with one of the PDOs at index greater<br /> than 4, and would be reflected in the request data object&amp;#39;s (RDO)<br /> object position field. This would result in an out-of-bounds access<br /> when the rdo_index() is used to index into the src_pdos array in<br /> ucsi_psy_get_voltage_now().<br /> <br /> With the help of the UBSAN -fsanitize=array-bounds checker enabled<br /> this exact issue is revealed when connecting to a PD source adapter<br /> that advertise 5 PDOs and the PPM enters a contract having selected<br /> the 5th one.<br /> <br /> [ 151.545106][ T70] Unexpected kernel BRK exception at EL1<br /> [ 151.545112][ T70] Internal error: BRK handler: f2005512 [#1] PREEMPT SMP<br /> ...<br /> [ 151.545499][ T70] pc : ucsi_psy_get_prop+0x208/0x20c<br /> [ 151.545507][ T70] lr : power_supply_show_property+0xc0/0x328<br /> ...<br /> [ 151.545542][ T70] Call trace:<br /> [ 151.545544][ T70] ucsi_psy_get_prop+0x208/0x20c<br /> [ 151.545546][ T70] power_supply_uevent+0x1a4/0x2f0<br /> [ 151.545550][ T70] dev_uevent+0x200/0x384<br /> [ 151.545555][ T70] kobject_uevent_env+0x1d4/0x7e8<br /> [ 151.545557][ T70] power_supply_changed_work+0x174/0x31c<br /> [ 151.545562][ T70] process_one_work+0x244/0x6f0<br /> [ 151.545564][ T70] worker_thread+0x3e0/0xa64<br /> <br /> We can resolve this by instead retrieving and storing up to the<br /> maximum of 7 PDOs in the con-&gt;src_pdos array. This would involve<br /> two calls to the GET_PDOS command.

In the Linux kernel, the following vulnerability has been resolved:<br /> <br /> nbd: Fix NULL pointer in flush_workqueue<br /> <br /> Open /dev/nbdX first, the config_refs will be 1 and<br /> the pointers in nbd_device are still null. Disconnect<br /> /dev/nbdX, then reference a null recv_workq. The<br /> protection by config_refs in nbd_genl_disconnect is useless.<br /> <br /> [ 656.366194] BUG: kernel NULL pointer dereference, address: 0000000000000020<br /> [ 656.368943] #PF: supervisor write access in kernel mode<br /> [ 656.369844] #PF: error_code(0x0002) - not-present page<br /> [ 656.370717] PGD 10cc87067 P4D 10cc87067 PUD 1074b4067 PMD 0<br /> [ 656.371693] Oops: 0002 [#1] SMP<br /> [ 656.372242] CPU: 5 PID: 7977 Comm: nbd-client Not tainted 5.11.0-rc5-00040-g76c057c84d28 #1<br /> [ 656.373661] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS ?-20190727_073836-buildvm-ppc64le-16.ppc.fedoraproject.org-3.fc31 04/01/2014<br /> [ 656.375904] RIP: 0010:mutex_lock+0x29/0x60<br /> [ 656.376627] Code: 00 0f 1f 44 00 00 55 48 89 fd 48 83 05 6f d7 fe 08 01 e8 7a c3 ff ff 48 83 05 6a d7 fe 08 01 31 c0 65 48 8b 14 25 00 6d 01 00 48 0f b1 55 d<br /> [ 656.378934] RSP: 0018:ffffc900005eb9b0 EFLAGS: 00010246<br /> [ 656.379350] RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000<br /> [ 656.379915] RDX: ffff888104cf2600 RSI: ffffffffaae8f452 RDI: 0000000000000020<br /> [ 656.380473] RBP: 0000000000000020 R08: 0000000000000000 R09: ffff88813bd6b318<br /> [ 656.381039] R10: 00000000000000c7 R11: fefefefefefefeff R12: ffff888102710b40<br /> [ 656.381599] R13: ffffc900005eb9e0 R14: ffffffffb2930680 R15: ffff88810770ef00<br /> [ 656.382166] FS: 00007fdf117ebb40(0000) GS:ffff88813bd40000(0000) knlGS:0000000000000000<br /> [ 656.382806] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033<br /> [ 656.383261] CR2: 0000000000000020 CR3: 0000000100c84000 CR4: 00000000000006e0<br /> [ 656.383819] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000<br /> [ 656.384370] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400<br /> [ 656.384927] Call Trace:<br /> [ 656.385111] flush_workqueue+0x92/0x6c0<br /> [ 656.385395] nbd_disconnect_and_put+0x81/0xd0<br /> [ 656.385716] nbd_genl_disconnect+0x125/0x2a0<br /> [ 656.386034] genl_family_rcv_msg_doit.isra.0+0x102/0x1b0<br /> [ 656.386422] genl_rcv_msg+0xfc/0x2b0<br /> [ 656.386685] ? nbd_ioctl+0x490/0x490<br /> [ 656.386954] ? genl_family_rcv_msg_doit.isra.0+0x1b0/0x1b0<br /> [ 656.387354] netlink_rcv_skb+0x62/0x180<br /> [ 656.387638] genl_rcv+0x34/0x60<br /> [ 656.387874] netlink_unicast+0x26d/0x590<br /> [ 656.388162] netlink_sendmsg+0x398/0x6c0<br /> [ 656.388451] ? netlink_rcv_skb+0x180/0x180<br /> [ 656.388750] ____sys_sendmsg+0x1da/0x320<br /> [ 656.389038] ? ____sys_recvmsg+0x130/0x220<br /> [ 656.389334] ___sys_sendmsg+0x8e/0xf0<br /> [ 656.389605] ? ___sys_recvmsg+0xa2/0xf0<br /> [ 656.389889] ? handle_mm_fault+0x1671/0x21d0<br /> [ 656.390201] __sys_sendmsg+0x6d/0xe0<br /> [ 656.390464] __x64_sys_sendmsg+0x23/0x30<br /> [ 656.390751] do_syscall_64+0x45/0x70<br /> [ 656.391017] entry_SYSCALL_64_after_hwframe+0x44/0xa9<br /> <br /> To fix it, just add if (nbd-&gt;recv_workq) to nbd_disconnect_and_put().