| CVE |
Vendors |
Products |
Updated |
CVSS v3.1 |
| In the Linux kernel, the following vulnerability has been resolved:
KVM: Don't null dereference ops->destroy
A KVM device cleanup happens in either of two callbacks:
1) destroy() which is called when the VM is being destroyed;
2) release() which is called when a device fd is closed.
Most KVM devices use 1) but Book3s's interrupt controller KVM devices
(XICS, XIVE, XIVE-native) use 2) as they need to close and reopen during
the machine execution. The error handling in kvm_ioctl_create_device()
assumes destroy() is always defined which leads to NULL dereference as
discovered by Syzkaller.
This adds a checks for destroy!=NULL and adds a missing release().
This is not changing kvm_destroy_devices() as devices with defined
release() should have been removed from the KVM devices list by then. |
| In the Linux kernel, the following vulnerability has been resolved:
ice: Do not use WQ_MEM_RECLAIM flag for workqueue
When both ice and the irdma driver are loaded, a warning in
check_flush_dependency is being triggered. This is due to ice driver
workqueue being allocated with the WQ_MEM_RECLAIM flag and the irdma one
is not.
According to kernel documentation, this flag should be set if the
workqueue will be involved in the kernel's memory reclamation flow.
Since it is not, there is no need for the ice driver's WQ to have this
flag set so remove it.
Example trace:
[ +0.000004] workqueue: WQ_MEM_RECLAIM ice:ice_service_task [ice] is flushing !WQ_MEM_RECLAIM infiniband:0x0
[ +0.000139] WARNING: CPU: 0 PID: 728 at kernel/workqueue.c:2632 check_flush_dependency+0x178/0x1a0
[ +0.000011] Modules linked in: bonding tls xt_CHECKSUM xt_MASQUERADE xt_conntrack ipt_REJECT nf_reject_ipv4 nft_compat nft_cha
in_nat nf_nat nf_conntrack nf_defrag_ipv6 nf_defrag_ipv4 nf_tables nfnetlink bridge stp llc rfkill vfat fat intel_rapl_msr intel
_rapl_common isst_if_common skx_edac nfit libnvdimm x86_pkg_temp_thermal intel_powerclamp coretemp kvm_intel kvm irqbypass crct1
0dif_pclmul crc32_pclmul ghash_clmulni_intel rapl intel_cstate rpcrdma sunrpc rdma_ucm ib_srpt ib_isert iscsi_target_mod target_
core_mod ib_iser libiscsi scsi_transport_iscsi rdma_cm ib_cm iw_cm iTCO_wdt iTCO_vendor_support ipmi_ssif irdma mei_me ib_uverbs
ib_core intel_uncore joydev pcspkr i2c_i801 acpi_ipmi mei lpc_ich i2c_smbus intel_pch_thermal ioatdma ipmi_si acpi_power_meter
acpi_pad xfs libcrc32c sd_mod t10_pi crc64_rocksoft crc64 sg ahci ixgbe libahci ice i40e igb crc32c_intel mdio i2c_algo_bit liba
ta dca wmi dm_mirror dm_region_hash dm_log dm_mod ipmi_devintf ipmi_msghandler fuse
[ +0.000161] [last unloaded: bonding]
[ +0.000006] CPU: 0 PID: 728 Comm: kworker/0:2 Tainted: G S 6.2.0-rc2_next-queue-13jan-00458-gc20aabd57164 #1
[ +0.000006] Hardware name: Intel Corporation S2600WFT/S2600WFT, BIOS SE5C620.86B.02.01.0010.010620200716 01/06/2020
[ +0.000003] Workqueue: ice ice_service_task [ice]
[ +0.000127] RIP: 0010:check_flush_dependency+0x178/0x1a0
[ +0.000005] Code: 89 8e 02 01 e8 49 3d 40 00 49 8b 55 18 48 8d 8d d0 00 00 00 48 8d b3 d0 00 00 00 4d 89 e0 48 c7 c7 e0 3b 08
9f e8 bb d3 07 01 <0f> 0b e9 be fe ff ff 80 3d 24 89 8e 02 00 0f 85 6b ff ff ff e9 06
[ +0.000004] RSP: 0018:ffff88810a39f990 EFLAGS: 00010282
[ +0.000005] RAX: 0000000000000000 RBX: ffff888141bc2400 RCX: 0000000000000000
[ +0.000004] RDX: 0000000000000001 RSI: dffffc0000000000 RDI: ffffffffa1213a80
[ +0.000003] RBP: ffff888194bf3400 R08: ffffed117b306112 R09: ffffed117b306112
[ +0.000003] R10: ffff888bd983088b R11: ffffed117b306111 R12: 0000000000000000
[ +0.000003] R13: ffff888111f84d00 R14: ffff88810a3943ac R15: ffff888194bf3400
[ +0.000004] FS: 0000000000000000(0000) GS:ffff888bd9800000(0000) knlGS:0000000000000000
[ +0.000003] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ +0.000003] CR2: 000056035b208b60 CR3: 000000017795e005 CR4: 00000000007706f0
[ +0.000003] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[ +0.000003] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[ +0.000002] PKRU: 55555554
[ +0.000003] Call Trace:
[ +0.000002] <TASK>
[ +0.000003] __flush_workqueue+0x203/0x840
[ +0.000006] ? mutex_unlock+0x84/0xd0
[ +0.000008] ? __pfx_mutex_unlock+0x10/0x10
[ +0.000004] ? __pfx___flush_workqueue+0x10/0x10
[ +0.000006] ? mutex_lock+0xa3/0xf0
[ +0.000005] ib_cache_cleanup_one+0x39/0x190 [ib_core]
[ +0.000174] __ib_unregister_device+0x84/0xf0 [ib_core]
[ +0.000094] ib_unregister_device+0x25/0x30 [ib_core]
[ +0.000093] irdma_ib_unregister_device+0x97/0xc0 [irdma]
[ +0.000064] ? __pfx_irdma_ib_unregister_device+0x10/0x10 [irdma]
[ +0.000059] ? up_write+0x5c/0x90
[ +0.000005] irdma_remove+0x36/0x90 [irdma]
[ +0.000062] auxiliary_bus_remove+0x32/0x50
[ +0.000007] device_r
---truncated--- |
| In the Linux kernel, the following vulnerability has been resolved:
bpf: Add oversize check before call kvcalloc()
Commit 7661809d493b ("mm: don't allow oversized kvmalloc() calls") add the
oversize check. When the allocation is larger than what kmalloc() supports,
the following warning triggered:
WARNING: CPU: 0 PID: 8408 at mm/util.c:597 kvmalloc_node+0x108/0x110 mm/util.c:597
Modules linked in:
CPU: 0 PID: 8408 Comm: syz-executor221 Not tainted 5.14.0-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:kvmalloc_node+0x108/0x110 mm/util.c:597
Call Trace:
kvmalloc include/linux/mm.h:806 [inline]
kvmalloc_array include/linux/mm.h:824 [inline]
kvcalloc include/linux/mm.h:829 [inline]
check_btf_line kernel/bpf/verifier.c:9925 [inline]
check_btf_info kernel/bpf/verifier.c:10049 [inline]
bpf_check+0xd634/0x150d0 kernel/bpf/verifier.c:13759
bpf_prog_load kernel/bpf/syscall.c:2301 [inline]
__sys_bpf+0x11181/0x126e0 kernel/bpf/syscall.c:4587
__do_sys_bpf kernel/bpf/syscall.c:4691 [inline]
__se_sys_bpf kernel/bpf/syscall.c:4689 [inline]
__x64_sys_bpf+0x78/0x90 kernel/bpf/syscall.c:4689
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x44/0xae |
| In the Linux kernel, the following vulnerability has been resolved:
KVM: PPC: Book3S HV: Fix stack handling in idle_kvm_start_guest()
In commit 10d91611f426 ("powerpc/64s: Reimplement book3s idle code in
C") kvm_start_guest() became idle_kvm_start_guest(). The old code
allocated a stack frame on the emergency stack, but didn't use the
frame to store anything, and also didn't store anything in its caller's
frame.
idle_kvm_start_guest() on the other hand is written more like a normal C
function, it creates a frame on entry, and also stores CR/LR into its
callers frame (per the ABI). The problem is that there is no caller
frame on the emergency stack.
The emergency stack for a given CPU is allocated with:
paca_ptrs[i]->emergency_sp = alloc_stack(limit, i) + THREAD_SIZE;
So emergency_sp actually points to the first address above the emergency
stack allocation for a given CPU, we must not store above it without
first decrementing it to create a frame. This is different to the
regular kernel stack, paca->kstack, which is initialised to point at an
initial frame that is ready to use.
idle_kvm_start_guest() stores the backchain, CR and LR all of which
write outside the allocation for the emergency stack. It then creates a
stack frame and saves the non-volatile registers. Unfortunately the
frame it creates is not large enough to fit the non-volatiles, and so
the saving of the non-volatile registers also writes outside the
emergency stack allocation.
The end result is that we corrupt whatever is at 0-24 bytes, and 112-248
bytes above the emergency stack allocation.
In practice this has gone unnoticed because the memory immediately above
the emergency stack happens to be used for other stack allocations,
either another CPUs mc_emergency_sp or an IRQ stack. See the order of
calls to irqstack_early_init() and emergency_stack_init().
The low addresses of another stack are the top of that stack, and so are
only used if that stack is under extreme pressue, which essentially
never happens in practice - and if it did there's a high likelyhood we'd
crash due to that stack overflowing.
Still, we shouldn't be corrupting someone else's stack, and it is purely
luck that we aren't corrupting something else.
To fix it we save CR/LR into the caller's frame using the existing r1 on
entry, we then create a SWITCH_FRAME_SIZE frame (which has space for
pt_regs) on the emergency stack with the backchain pointing to the
existing stack, and then finally we switch to the new frame on the
emergency stack. |
| In the Linux kernel, the following vulnerability has been resolved:
drm: Check output polling initialized before disabling
In drm_kms_helper_poll_disable() check if output polling
support is initialized before disabling polling. If not flag
this as a warning.
Additionally in drm_mode_config_helper_suspend() and
drm_mode_config_helper_resume() calls, that re the callers of these
functions, avoid invoking them if polling is not initialized.
For drivers like hyperv-drm, that do not initialize connector
polling, if suspend is called without this check, it leads to
suspend failure with following stack
[ 770.719392] Freezing remaining freezable tasks ... (elapsed 0.001 seconds) done.
[ 770.720592] printk: Suspending console(s) (use no_console_suspend to debug)
[ 770.948823] ------------[ cut here ]------------
[ 770.948824] WARNING: CPU: 1 PID: 17197 at kernel/workqueue.c:3162 __flush_work.isra.0+0x212/0x230
[ 770.948831] Modules linked in: rfkill nft_counter xt_conntrack xt_owner udf nft_compat crc_itu_t nft_fib_inet nft_fib_ipv4 nft_fib_ipv6 nft_fib nft_reject_inet nf_reject_ipv4 nf_reject_ipv6 nft_reject nft_ct nft_chain_nat nf_nat nf_conntrack nf_defrag_ipv6 nf_defrag_ipv4 ip_set nf_tables nfnetlink vfat fat mlx5_ib ib_uverbs ib_core mlx5_core intel_rapl_msr intel_rapl_common kvm_amd ccp mlxfw kvm psample hyperv_drm tls drm_shmem_helper drm_kms_helper irqbypass pcspkr syscopyarea sysfillrect sysimgblt hv_balloon hv_utils joydev drm fuse xfs libcrc32c pci_hyperv pci_hyperv_intf sr_mod sd_mod cdrom t10_pi sg hv_storvsc scsi_transport_fc hv_netvsc serio_raw hyperv_keyboard hid_hyperv crct10dif_pclmul crc32_pclmul crc32c_intel hv_vmbus ghash_clmulni_intel dm_mirror dm_region_hash dm_log dm_mod
[ 770.948863] CPU: 1 PID: 17197 Comm: systemd-sleep Not tainted 5.14.0-362.2.1.el9_3.x86_64 #1
[ 770.948865] Hardware name: Microsoft Corporation Virtual Machine/Virtual Machine, BIOS Hyper-V UEFI Release v4.1 05/09/2022
[ 770.948866] RIP: 0010:__flush_work.isra.0+0x212/0x230
[ 770.948869] Code: 8b 4d 00 4c 8b 45 08 89 ca 48 c1 e9 04 83 e2 08 83 e1 0f 83 ca 02 89 c8 48 0f ba 6d 00 03 e9 25 ff ff ff 0f 0b e9 4e ff ff ff <0f> 0b 45 31 ed e9 44 ff ff ff e8 8f 89 b2 00 66 66 2e 0f 1f 84 00
[ 770.948870] RSP: 0018:ffffaf4ac213fb10 EFLAGS: 00010246
[ 770.948871] RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffffffff8c992857
[ 770.948872] RDX: 0000000000000001 RSI: 0000000000000001 RDI: ffff9aad82b00330
[ 770.948873] RBP: ffff9aad82b00330 R08: 0000000000000000 R09: ffff9aad87ee3d10
[ 770.948874] R10: 0000000000000200 R11: 0000000000000000 R12: ffff9aad82b00330
[ 770.948874] R13: 0000000000000001 R14: 0000000000000000 R15: 0000000000000001
[ 770.948875] FS: 00007ff1b2f6bb40(0000) GS:ffff9aaf37d00000(0000) knlGS:0000000000000000
[ 770.948878] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 770.948878] CR2: 0000555f345cb666 CR3: 00000001462dc005 CR4: 0000000000370ee0
[ 770.948879] Call Trace:
[ 770.948880] <TASK>
[ 770.948881] ? show_trace_log_lvl+0x1c4/0x2df
[ 770.948884] ? show_trace_log_lvl+0x1c4/0x2df
[ 770.948886] ? __cancel_work_timer+0x103/0x190
[ 770.948887] ? __flush_work.isra.0+0x212/0x230
[ 770.948889] ? __warn+0x81/0x110
[ 770.948891] ? __flush_work.isra.0+0x212/0x230
[ 770.948892] ? report_bug+0x10a/0x140
[ 770.948895] ? handle_bug+0x3c/0x70
[ 770.948898] ? exc_invalid_op+0x14/0x70
[ 770.948899] ? asm_exc_invalid_op+0x16/0x20
[ 770.948903] ? __flush_work.isra.0+0x212/0x230
[ 770.948905] __cancel_work_timer+0x103/0x190
[ 770.948907] ? _raw_spin_unlock_irqrestore+0xa/0x30
[ 770.948910] drm_kms_helper_poll_disable+0x1e/0x40 [drm_kms_helper]
[ 770.948923] drm_mode_config_helper_suspend+0x1c/0x80 [drm_kms_helper]
[ 770.948933] ? __pfx_vmbus_suspend+0x10/0x10 [hv_vmbus]
[ 770.948942] hyperv_vmbus_suspend+0x17/0x40 [hyperv_drm]
[ 770.948944] ? __pfx_vmbus_suspend+0x10/0x10 [hv_vmbus]
[ 770.948951] dpm_run_callback+0x4c/0x140
[ 770.948954] __device_suspend_noir
---truncated--- |
| In the Linux kernel, the following vulnerability has been resolved:
powerpc/tm: Fix more userspace r13 corruption
Commit cf13435b730a ("powerpc/tm: Fix userspace r13 corruption") fixes a
problem in treclaim where a SLB miss can occur on the
thread_struct->ckpt_regs while SCRATCH0 is live with the saved user r13
value, clobbering it with the kernel r13 and ultimately resulting in
kernel r13 being stored in ckpt_regs.
There is an equivalent problem in trechkpt where the user r13 value is
loaded into r13 from chkpt_regs to be recheckpointed, but a SLB miss
could occur on ckpt_regs accesses after that, which will result in r13
being clobbered with a kernel value and that will get recheckpointed and
then restored to user registers.
The same memory page is accessed right before this critical window where
a SLB miss could cause corruption, so hitting the bug requires the SLB
entry be removed within a small window of instructions, which is
possible if a SLB related MCE hits there. PAPR also permits the
hypervisor to discard this SLB entry (because slb_shadow->persistent is
only set to SLB_NUM_BOLTED) although it's not known whether any
implementations would do this (KVM does not). So this is an extremely
unlikely bug, only found by inspection.
Fix this by also storing user r13 in a temporary location on the kernel
stack and don't change the r13 register from kernel r13 until the RI=0
critical section that does not fault.
The SCRATCH0 change is not strictly part of the fix, it's only used in
the RI=0 section so it does not have the same problem as the previous
SCRATCH0 bug. |
| In the Linux kernel, the following vulnerability has been resolved:
ice: Don't double unplug aux on peer initiated reset
In the IDC callback that is accessed when the aux drivers request a reset,
the function to unplug the aux devices is called. This function is also
called in the ice_prepare_for_reset function. This double call is causing
a "scheduling while atomic" BUG.
[ 662.676430] ice 0000:4c:00.0 rocep76s0: cqp opcode = 0x1 maj_err_code = 0xffff min_err_code = 0x8003
[ 662.676609] ice 0000:4c:00.0 rocep76s0: [Modify QP Cmd Error][op_code=8] status=-29 waiting=1 completion_err=1 maj=0xffff min=0x8003
[ 662.815006] ice 0000:4c:00.0 rocep76s0: ICE OICR event notification: oicr = 0x10000003
[ 662.815014] ice 0000:4c:00.0 rocep76s0: critical PE Error, GLPE_CRITERR=0x00011424
[ 662.815017] ice 0000:4c:00.0 rocep76s0: Requesting a reset
[ 662.815475] BUG: scheduling while atomic: swapper/37/0/0x00010002
[ 662.815475] BUG: scheduling while atomic: swapper/37/0/0x00010002
[ 662.815477] Modules linked in: rpcsec_gss_krb5 auth_rpcgss nfsv4 dns_resolver nfs lockd grace fscache netfs rfkill 8021q garp mrp stp llc vfat fat rpcrdma intel_rapl_msr intel_rapl_common sunrpc i10nm_edac rdma_ucm nfit ib_srpt libnvdimm ib_isert iscsi_target_mod x86_pkg_temp_thermal intel_powerclamp coretemp target_core_mod snd_hda_intel ib_iser snd_intel_dspcfg libiscsi snd_intel_sdw_acpi scsi_transport_iscsi kvm_intel iTCO_wdt rdma_cm snd_hda_codec kvm iw_cm ipmi_ssif iTCO_vendor_support snd_hda_core irqbypass crct10dif_pclmul crc32_pclmul ghash_clmulni_intel snd_hwdep snd_seq snd_seq_device rapl snd_pcm snd_timer isst_if_mbox_pci pcspkr isst_if_mmio irdma intel_uncore idxd acpi_ipmi joydev isst_if_common snd mei_me idxd_bus ipmi_si soundcore i2c_i801 mei ipmi_devintf i2c_smbus i2c_ismt ipmi_msghandler acpi_power_meter acpi_pad rv(OE) ib_uverbs ib_cm ib_core xfs libcrc32c ast i2c_algo_bit drm_vram_helper drm_kms_helper syscopyarea sysfillrect sysimgblt fb_sys_fops drm_ttm_helpe
r ttm
[ 662.815546] nvme nvme_core ice drm crc32c_intel i40e t10_pi wmi pinctrl_emmitsburg dm_mirror dm_region_hash dm_log dm_mod fuse
[ 662.815557] Preemption disabled at:
[ 662.815558] [<0000000000000000>] 0x0
[ 662.815563] CPU: 37 PID: 0 Comm: swapper/37 Kdump: loaded Tainted: G S OE 5.17.1 #2
[ 662.815566] Hardware name: Intel Corporation D50DNP/D50DNP, BIOS SE5C6301.86B.6624.D18.2111021741 11/02/2021
[ 662.815568] Call Trace:
[ 662.815572] <IRQ>
[ 662.815574] dump_stack_lvl+0x33/0x42
[ 662.815581] __schedule_bug.cold.147+0x7d/0x8a
[ 662.815588] __schedule+0x798/0x990
[ 662.815595] schedule+0x44/0xc0
[ 662.815597] schedule_preempt_disabled+0x14/0x20
[ 662.815600] __mutex_lock.isra.11+0x46c/0x490
[ 662.815603] ? __ibdev_printk+0x76/0xc0 [ib_core]
[ 662.815633] device_del+0x37/0x3d0
[ 662.815639] ice_unplug_aux_dev+0x1a/0x40 [ice]
[ 662.815674] ice_schedule_reset+0x3c/0xd0 [ice]
[ 662.815693] irdma_iidc_event_handler.cold.7+0xb6/0xd3 [irdma]
[ 662.815712] ? bitmap_find_next_zero_area_off+0x45/0xa0
[ 662.815719] ice_send_event_to_aux+0x54/0x70 [ice]
[ 662.815741] ice_misc_intr+0x21d/0x2d0 [ice]
[ 662.815756] __handle_irq_event_percpu+0x4c/0x180
[ 662.815762] handle_irq_event_percpu+0xf/0x40
[ 662.815764] handle_irq_event+0x34/0x60
[ 662.815766] handle_edge_irq+0x9a/0x1c0
[ 662.815770] __common_interrupt+0x62/0x100
[ 662.815774] common_interrupt+0xb4/0xd0
[ 662.815779] </IRQ>
[ 662.815780] <TASK>
[ 662.815780] asm_common_interrupt+0x1e/0x40
[ 662.815785] RIP: 0010:cpuidle_enter_state+0xd6/0x380
[ 662.815789] Code: 49 89 c4 0f 1f 44 00 00 31 ff e8 65 d7 95 ff 45 84 ff 74 12 9c 58 f6 c4 02 0f 85 64 02 00 00 31 ff e8 ae c5 9c ff fb 45 85 f6 <0f> 88 12 01 00 00 49 63 d6 4c 2b 24 24 48 8d 04 52 48 8d 04 82 49
[ 662.815791] RSP: 0018:ff2c2c4f18edbe80 EFLAGS: 00000202
[ 662.815793] RAX: ff280805df140000 RBX: 0000000000000002 RCX: 000000000000001f
[ 662.815795] RDX: 0000009a52da2d08 R
---truncated--- |
| In the Linux kernel, the following vulnerability has been resolved:
drm/amdgpu: Fix a null pointer access when the smc_rreg pointer is NULL
In certain types of chips, such as VEGA20, reading the amdgpu_regs_smc file could result in an abnormal null pointer access when the smc_rreg pointer is NULL. Below are the steps to reproduce this issue and the corresponding exception log:
1. Navigate to the directory: /sys/kernel/debug/dri/0
2. Execute command: cat amdgpu_regs_smc
3. Exception Log::
[4005007.702554] BUG: kernel NULL pointer dereference, address: 0000000000000000
[4005007.702562] #PF: supervisor instruction fetch in kernel mode
[4005007.702567] #PF: error_code(0x0010) - not-present page
[4005007.702570] PGD 0 P4D 0
[4005007.702576] Oops: 0010 [#1] SMP NOPTI
[4005007.702581] CPU: 4 PID: 62563 Comm: cat Tainted: G OE 5.15.0-43-generic #46-Ubunt u
[4005007.702590] RIP: 0010:0x0
[4005007.702598] Code: Unable to access opcode bytes at RIP 0xffffffffffffffd6.
[4005007.702600] RSP: 0018:ffffa82b46d27da0 EFLAGS: 00010206
[4005007.702605] RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffffa82b46d27e68
[4005007.702609] RDX: 0000000000000001 RSI: 0000000000000000 RDI: ffff9940656e0000
[4005007.702612] RBP: ffffa82b46d27dd8 R08: 0000000000000000 R09: ffff994060c07980
[4005007.702615] R10: 0000000000020000 R11: 0000000000000000 R12: 00007f5e06753000
[4005007.702618] R13: ffff9940656e0000 R14: ffffa82b46d27e68 R15: 00007f5e06753000
[4005007.702622] FS: 00007f5e0755b740(0000) GS:ffff99479d300000(0000) knlGS:0000000000000000
[4005007.702626] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[4005007.702629] CR2: ffffffffffffffd6 CR3: 00000003253fc000 CR4: 00000000003506e0
[4005007.702633] Call Trace:
[4005007.702636] <TASK>
[4005007.702640] amdgpu_debugfs_regs_smc_read+0xb0/0x120 [amdgpu]
[4005007.703002] full_proxy_read+0x5c/0x80
[4005007.703011] vfs_read+0x9f/0x1a0
[4005007.703019] ksys_read+0x67/0xe0
[4005007.703023] __x64_sys_read+0x19/0x20
[4005007.703028] do_syscall_64+0x5c/0xc0
[4005007.703034] ? do_user_addr_fault+0x1e3/0x670
[4005007.703040] ? exit_to_user_mode_prepare+0x37/0xb0
[4005007.703047] ? irqentry_exit_to_user_mode+0x9/0x20
[4005007.703052] ? irqentry_exit+0x19/0x30
[4005007.703057] ? exc_page_fault+0x89/0x160
[4005007.703062] ? asm_exc_page_fault+0x8/0x30
[4005007.703068] entry_SYSCALL_64_after_hwframe+0x44/0xae
[4005007.703075] RIP: 0033:0x7f5e07672992
[4005007.703079] Code: c0 e9 b2 fe ff ff 50 48 8d 3d fa b2 0c 00 e8 c5 1d 02 00 0f 1f 44 00 00 f3 0f 1e fa 64 8b 04 25 18 00 00 00 85 c0 75 10 0f 05 <48> 3d 00 f0 ff ff 77 56 c3 0f 1f 44 00 00 48 83 e c 28 48 89 54 24
[4005007.703083] RSP: 002b:00007ffe03097898 EFLAGS: 00000246 ORIG_RAX: 0000000000000000
[4005007.703088] RAX: ffffffffffffffda RBX: 0000000000020000 RCX: 00007f5e07672992
[4005007.703091] RDX: 0000000000020000 RSI: 00007f5e06753000 RDI: 0000000000000003
[4005007.703094] RBP: 00007f5e06753000 R08: 00007f5e06752010 R09: 00007f5e06752010
[4005007.703096] R10: 0000000000000022 R11: 0000000000000246 R12: 0000000000022000
[4005007.703099] R13: 0000000000000003 R14: 0000000000020000 R15: 0000000000020000
[4005007.703105] </TASK>
[4005007.703107] Modules linked in: nf_tables libcrc32c nfnetlink algif_hash af_alg binfmt_misc nls_ iso8859_1 ipmi_ssif ast intel_rapl_msr intel_rapl_common drm_vram_helper drm_ttm_helper amd64_edac t tm edac_mce_amd kvm_amd ccp mac_hid k10temp kvm acpi_ipmi ipmi_si rapl sch_fq_codel ipmi_devintf ipm i_msghandler msr parport_pc ppdev lp parport mtd pstore_blk efi_pstore ramoops pstore_zone reed_solo mon ip_tables x_tables autofs4 ib_uverbs ib_core amdgpu(OE) amddrm_ttm_helper(OE) amdttm(OE) iommu_v 2 amd_sched(OE) amdkcl(OE) drm_kms_helper syscopyarea sysfillrect sysimgblt fb_sys_fops cec rc_core drm igb ahci xhci_pci libahci i2c_piix4 i2c_algo_bit xhci_pci_renesas dca
[4005007.703184] CR2: 0000000000000000
[4005007.703188] ---[ en
---truncated--- |
| In the Linux kernel, the following vulnerability has been resolved:
bfq: Avoid merging queues with different parents
It can happen that the parent of a bfqq changes between the moment we
decide two queues are worth to merge (and set bic->stable_merge_bfqq)
and the moment bfq_setup_merge() is called. This can happen e.g. because
the process submitted IO for a different cgroup and thus bfqq got
reparented. It can even happen that the bfqq we are merging with has
parent cgroup that is already offline and going to be destroyed in which
case the merge can lead to use-after-free issues such as:
BUG: KASAN: use-after-free in __bfq_deactivate_entity+0x9cb/0xa50
Read of size 8 at addr ffff88800693c0c0 by task runc:[2:INIT]/10544
CPU: 0 PID: 10544 Comm: runc:[2:INIT] Tainted: G E 5.15.2-0.g5fb85fd-default #1 openSUSE Tumbleweed (unreleased) f1f3b891c72369aebecd2e43e4641a6358867c70
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.14.0-0-g155821a-rebuilt.opensuse.org 04/01/2014
Call Trace:
<IRQ>
dump_stack_lvl+0x46/0x5a
print_address_description.constprop.0+0x1f/0x140
? __bfq_deactivate_entity+0x9cb/0xa50
kasan_report.cold+0x7f/0x11b
? __bfq_deactivate_entity+0x9cb/0xa50
__bfq_deactivate_entity+0x9cb/0xa50
? update_curr+0x32f/0x5d0
bfq_deactivate_entity+0xa0/0x1d0
bfq_del_bfqq_busy+0x28a/0x420
? resched_curr+0x116/0x1d0
? bfq_requeue_bfqq+0x70/0x70
? check_preempt_wakeup+0x52b/0xbc0
__bfq_bfqq_expire+0x1a2/0x270
bfq_bfqq_expire+0xd16/0x2160
? try_to_wake_up+0x4ee/0x1260
? bfq_end_wr_async_queues+0xe0/0xe0
? _raw_write_unlock_bh+0x60/0x60
? _raw_spin_lock_irq+0x81/0xe0
bfq_idle_slice_timer+0x109/0x280
? bfq_dispatch_request+0x4870/0x4870
__hrtimer_run_queues+0x37d/0x700
? enqueue_hrtimer+0x1b0/0x1b0
? kvm_clock_get_cycles+0xd/0x10
? ktime_get_update_offsets_now+0x6f/0x280
hrtimer_interrupt+0x2c8/0x740
Fix the problem by checking that the parent of the two bfqqs we are
merging in bfq_setup_merge() is the same. |
| In the Linux kernel, the following vulnerability has been resolved:
KVM: s390: fix setting of fpc register
kvm_arch_vcpu_ioctl_set_fpu() allows to set the floating point control
(fpc) register of a guest cpu. The new value is tested for validity by
temporarily loading it into the fpc register.
This may lead to corruption of the fpc register of the host process:
if an interrupt happens while the value is temporarily loaded into the fpc
register, and within interrupt context floating point or vector registers
are used, the current fp/vx registers are saved with save_fpu_regs()
assuming they belong to user space and will be loaded into fp/vx registers
when returning to user space.
test_fp_ctl() restores the original user space / host process fpc register
value, however it will be discarded, when returning to user space.
In result the host process will incorrectly continue to run with the value
that was supposed to be used for a guest cpu.
Fix this by simply removing the test. There is another test right before
the SIE context is entered which will handles invalid values.
This results in a change of behaviour: invalid values will now be accepted
instead of that the ioctl fails with -EINVAL. This seems to be acceptable,
given that this interface is most likely not used anymore, and this is in
addition the same behaviour implemented with the memory mapped interface
(replace invalid values with zero) - see sync_regs() in kvm-s390.c. |
| In the Linux kernel, the following vulnerability has been resolved:
x86/kvm: Disable kvmclock on all CPUs on shutdown
Currenly, we disable kvmclock from machine_shutdown() hook and this
only happens for boot CPU. We need to disable it for all CPUs to
guard against memory corruption e.g. on restore from hibernate.
Note, writing '0' to kvmclock MSR doesn't clear memory location, it
just prevents hypervisor from updating the location so for the short
while after write and while CPU is still alive, the clock remains usable
and correct so we don't need to switch to some other clocksource. |
| A flaw was found in the KVM's AMD nested virtualization (SVM). A malicious L1 guest could purposely fail to intercept the shutdown of a cooperative nested guest (L2), possibly leading to a page fault and kernel panic in the host (L0). |
| An issue was discovered the x86 KVM subsystem in the Linux kernel before 5.18.17. Unprivileged guest users can compromise the guest kernel because TLB flush operations are mishandled in certain KVM_VCPU_PREEMPTED situations. |
| In the Linux kernel, the following vulnerability has been resolved:
KVM: mmio: Fix use-after-free Read in kvm_vm_ioctl_unregister_coalesced_mmio
BUG: KASAN: use-after-free in kvm_vm_ioctl_unregister_coalesced_mmio+0x7c/0x1ec arch/arm64/kvm/../../../virt/kvm/coalesced_mmio.c:183
Read of size 8 at addr ffff0000c03a2500 by task syz-executor083/4269
CPU: 5 PID: 4269 Comm: syz-executor083 Not tainted 5.10.0 #7
Hardware name: linux,dummy-virt (DT)
Call trace:
dump_backtrace+0x0/0x2d0 arch/arm64/kernel/stacktrace.c:132
show_stack+0x28/0x34 arch/arm64/kernel/stacktrace.c:196
__dump_stack lib/dump_stack.c:77 [inline]
dump_stack+0x110/0x164 lib/dump_stack.c:118
print_address_description+0x78/0x5c8 mm/kasan/report.c:385
__kasan_report mm/kasan/report.c:545 [inline]
kasan_report+0x148/0x1e4 mm/kasan/report.c:562
check_memory_region_inline mm/kasan/generic.c:183 [inline]
__asan_load8+0xb4/0xbc mm/kasan/generic.c:252
kvm_vm_ioctl_unregister_coalesced_mmio+0x7c/0x1ec arch/arm64/kvm/../../../virt/kvm/coalesced_mmio.c:183
kvm_vm_ioctl+0xe30/0x14c4 arch/arm64/kvm/../../../virt/kvm/kvm_main.c:3755
vfs_ioctl fs/ioctl.c:48 [inline]
__do_sys_ioctl fs/ioctl.c:753 [inline]
__se_sys_ioctl fs/ioctl.c:739 [inline]
__arm64_sys_ioctl+0xf88/0x131c fs/ioctl.c:739
__invoke_syscall arch/arm64/kernel/syscall.c:36 [inline]
invoke_syscall arch/arm64/kernel/syscall.c:48 [inline]
el0_svc_common arch/arm64/kernel/syscall.c:158 [inline]
do_el0_svc+0x120/0x290 arch/arm64/kernel/syscall.c:220
el0_svc+0x1c/0x28 arch/arm64/kernel/entry-common.c:367
el0_sync_handler+0x98/0x170 arch/arm64/kernel/entry-common.c:383
el0_sync+0x140/0x180 arch/arm64/kernel/entry.S:670
Allocated by task 4269:
stack_trace_save+0x80/0xb8 kernel/stacktrace.c:121
kasan_save_stack mm/kasan/common.c:48 [inline]
kasan_set_track mm/kasan/common.c:56 [inline]
__kasan_kmalloc+0xdc/0x120 mm/kasan/common.c:461
kasan_kmalloc+0xc/0x14 mm/kasan/common.c:475
kmem_cache_alloc_trace include/linux/slab.h:450 [inline]
kmalloc include/linux/slab.h:552 [inline]
kzalloc include/linux/slab.h:664 [inline]
kvm_vm_ioctl_register_coalesced_mmio+0x78/0x1cc arch/arm64/kvm/../../../virt/kvm/coalesced_mmio.c:146
kvm_vm_ioctl+0x7e8/0x14c4 arch/arm64/kvm/../../../virt/kvm/kvm_main.c:3746
vfs_ioctl fs/ioctl.c:48 [inline]
__do_sys_ioctl fs/ioctl.c:753 [inline]
__se_sys_ioctl fs/ioctl.c:739 [inline]
__arm64_sys_ioctl+0xf88/0x131c fs/ioctl.c:739
__invoke_syscall arch/arm64/kernel/syscall.c:36 [inline]
invoke_syscall arch/arm64/kernel/syscall.c:48 [inline]
el0_svc_common arch/arm64/kernel/syscall.c:158 [inline]
do_el0_svc+0x120/0x290 arch/arm64/kernel/syscall.c:220
el0_svc+0x1c/0x28 arch/arm64/kernel/entry-common.c:367
el0_sync_handler+0x98/0x170 arch/arm64/kernel/entry-common.c:383
el0_sync+0x140/0x180 arch/arm64/kernel/entry.S:670
Freed by task 4269:
stack_trace_save+0x80/0xb8 kernel/stacktrace.c:121
kasan_save_stack mm/kasan/common.c:48 [inline]
kasan_set_track+0x38/0x6c mm/kasan/common.c:56
kasan_set_free_info+0x20/0x40 mm/kasan/generic.c:355
__kasan_slab_free+0x124/0x150 mm/kasan/common.c:422
kasan_slab_free+0x10/0x1c mm/kasan/common.c:431
slab_free_hook mm/slub.c:1544 [inline]
slab_free_freelist_hook mm/slub.c:1577 [inline]
slab_free mm/slub.c:3142 [inline]
kfree+0x104/0x38c mm/slub.c:4124
coalesced_mmio_destructor+0x94/0xa4 arch/arm64/kvm/../../../virt/kvm/coalesced_mmio.c:102
kvm_iodevice_destructor include/kvm/iodev.h:61 [inline]
kvm_io_bus_unregister_dev+0x248/0x280 arch/arm64/kvm/../../../virt/kvm/kvm_main.c:4374
kvm_vm_ioctl_unregister_coalesced_mmio+0x158/0x1ec arch/arm64/kvm/../../../virt/kvm/coalesced_mmio.c:186
kvm_vm_ioctl+0xe30/0x14c4 arch/arm64/kvm/../../../virt/kvm/kvm_main.c:3755
vfs_ioctl fs/ioctl.c:48 [inline]
__do_sys_ioctl fs/ioctl.c:753 [inline]
__se_sys_ioctl fs/ioctl.c:739 [inline]
__arm64_sys_ioctl+0xf88/0x131c fs/ioctl.c:739
__invoke_syscall arch/arm64/kernel/syscall.c:36 [inline]
invoke_syscall arch/arm64/kernel/sys
---truncated--- |
| In the Linux kernel, the following vulnerability has been resolved:
KVM: Destroy I/O bus devices on unregister failure _after_ sync'ing SRCU
If allocating a new instance of an I/O bus fails when unregistering a
device, wait to destroy the device until after all readers are guaranteed
to see the new null bus. Destroying devices before the bus is nullified
could lead to use-after-free since readers expect the devices on their
reference of the bus to remain valid. |
| In the Linux kernel, the following vulnerability has been resolved:
zram: fix NULL pointer in comp_algorithm_show()
LTP reported a NULL pointer dereference as followed:
CPU: 7 UID: 0 PID: 5995 Comm: cat Kdump: loaded Not tainted 6.12.0-rc6+ #3
Hardware name: QEMU KVM Virtual Machine, BIOS 0.0.0 02/06/2015
pstate: 40400005 (nZcv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
pc : __pi_strcmp+0x24/0x140
lr : zcomp_available_show+0x60/0x100 [zram]
sp : ffff800088b93b90
x29: ffff800088b93b90 x28: 0000000000000001 x27: 0000000000400cc0
x26: 0000000000000ffe x25: ffff80007b3e2388 x24: 0000000000000000
x23: ffff80007b3e2390 x22: ffff0004041a9000 x21: ffff80007b3e2900
x20: 0000000000000000 x19: 0000000000000000 x18: 0000000000000000
x17: 0000000000000000 x16: 0000000000000000 x15: 0000000000000000
x14: 0000000000000000 x13: 0000000000000000 x12: 0000000000000000
x11: 0000000000000000 x10: ffff80007b3e2900 x9 : ffff80007b3cb280
x8 : 0101010101010101 x7 : 0000000000000000 x6 : 0000000000000000
x5 : 0000000000000040 x4 : 0000000000000000 x3 : 00656c722d6f7a6c
x2 : 0000000000000000 x1 : ffff80007b3e2900 x0 : 0000000000000000
Call trace:
__pi_strcmp+0x24/0x140
comp_algorithm_show+0x40/0x70 [zram]
dev_attr_show+0x28/0x80
sysfs_kf_seq_show+0x90/0x140
kernfs_seq_show+0x34/0x48
seq_read_iter+0x1d4/0x4e8
kernfs_fop_read_iter+0x40/0x58
new_sync_read+0x9c/0x168
vfs_read+0x1a8/0x1f8
ksys_read+0x74/0x108
__arm64_sys_read+0x24/0x38
invoke_syscall+0x50/0x120
el0_svc_common.constprop.0+0xc8/0xf0
do_el0_svc+0x24/0x38
el0_svc+0x38/0x138
el0t_64_sync_handler+0xc0/0xc8
el0t_64_sync+0x188/0x190
The zram->comp_algs[ZRAM_PRIMARY_COMP] can be NULL in zram_add() if
comp_algorithm_set() has not been called. User can access the zram device
by sysfs after device_add_disk(), so there is a time window to trigger the
NULL pointer dereference. Move it ahead device_add_disk() to make sure
when user can access the zram device, it is ready. comp_algorithm_set()
is protected by zram->init_lock in other places and no such problem. |
| In the Linux kernel, the following vulnerability has been resolved:
KVM: arm64: Unregister redistributor for failed vCPU creation
Alex reports that syzkaller has managed to trigger a use-after-free when
tearing down a VM:
BUG: KASAN: slab-use-after-free in kvm_put_kvm+0x300/0xe68 virt/kvm/kvm_main.c:5769
Read of size 8 at addr ffffff801c6890d0 by task syz.3.2219/10758
CPU: 3 UID: 0 PID: 10758 Comm: syz.3.2219 Not tainted 6.11.0-rc6-dirty #64
Hardware name: linux,dummy-virt (DT)
Call trace:
dump_backtrace+0x17c/0x1a8 arch/arm64/kernel/stacktrace.c:317
show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:324
__dump_stack lib/dump_stack.c:93 [inline]
dump_stack_lvl+0x94/0xc0 lib/dump_stack.c:119
print_report+0x144/0x7a4 mm/kasan/report.c:377
kasan_report+0xcc/0x128 mm/kasan/report.c:601
__asan_report_load8_noabort+0x20/0x2c mm/kasan/report_generic.c:381
kvm_put_kvm+0x300/0xe68 virt/kvm/kvm_main.c:5769
kvm_vm_release+0x4c/0x60 virt/kvm/kvm_main.c:1409
__fput+0x198/0x71c fs/file_table.c:422
____fput+0x20/0x30 fs/file_table.c:450
task_work_run+0x1cc/0x23c kernel/task_work.c:228
do_notify_resume+0x144/0x1a0 include/linux/resume_user_mode.h:50
el0_svc+0x64/0x68 arch/arm64/kernel/entry-common.c:169
el0t_64_sync_handler+0x90/0xfc arch/arm64/kernel/entry-common.c:730
el0t_64_sync+0x190/0x194 arch/arm64/kernel/entry.S:598
Upon closer inspection, it appears that we do not properly tear down the
MMIO registration for a vCPU that fails creation late in the game, e.g.
a vCPU w/ the same ID already exists in the VM.
It is important to consider the context of commit that introduced this bug
by moving the unregistration out of __kvm_vgic_vcpu_destroy(). That
change correctly sought to avoid an srcu v. config_lock inversion by
breaking up the vCPU teardown into two parts, one guarded by the
config_lock.
Fix the use-after-free while avoiding lock inversion by adding a
special-cased unregistration to __kvm_vgic_vcpu_destroy(). This is safe
because failed vCPUs are torn down outside of the config_lock. |
| In the Linux kernel, the following vulnerability has been resolved:
KVM: Use dedicated mutex to protect kvm_usage_count to avoid deadlock
Use a dedicated mutex to guard kvm_usage_count to fix a potential deadlock
on x86 due to a chain of locks and SRCU synchronizations. Translating the
below lockdep splat, CPU1 #6 will wait on CPU0 #1, CPU0 #8 will wait on
CPU2 #3, and CPU2 #7 will wait on CPU1 #4 (if there's a writer, due to the
fairness of r/w semaphores).
CPU0 CPU1 CPU2
1 lock(&kvm->slots_lock);
2 lock(&vcpu->mutex);
3 lock(&kvm->srcu);
4 lock(cpu_hotplug_lock);
5 lock(kvm_lock);
6 lock(&kvm->slots_lock);
7 lock(cpu_hotplug_lock);
8 sync(&kvm->srcu);
Note, there are likely more potential deadlocks in KVM x86, e.g. the same
pattern of taking cpu_hotplug_lock outside of kvm_lock likely exists with
__kvmclock_cpufreq_notifier():
cpuhp_cpufreq_online()
|
-> cpufreq_online()
|
-> cpufreq_gov_performance_limits()
|
-> __cpufreq_driver_target()
|
-> __target_index()
|
-> cpufreq_freq_transition_begin()
|
-> cpufreq_notify_transition()
|
-> ... __kvmclock_cpufreq_notifier()
But, actually triggering such deadlocks is beyond rare due to the
combination of dependencies and timings involved. E.g. the cpufreq
notifier is only used on older CPUs without a constant TSC, mucking with
the NX hugepage mitigation while VMs are running is very uncommon, and
doing so while also onlining/offlining a CPU (necessary to generate
contention on cpu_hotplug_lock) would be even more unusual.
The most robust solution to the general cpu_hotplug_lock issue is likely
to switch vm_list to be an RCU-protected list, e.g. so that x86's cpufreq
notifier doesn't to take kvm_lock. For now, settle for fixing the most
blatant deadlock, as switching to an RCU-protected list is a much more
involved change, but add a comment in locking.rst to call out that care
needs to be taken when walking holding kvm_lock and walking vm_list.
======================================================
WARNING: possible circular locking dependency detected
6.10.0-smp--c257535a0c9d-pip #330 Tainted: G S O
------------------------------------------------------
tee/35048 is trying to acquire lock:
ff6a80eced71e0a8 (&kvm->slots_lock){+.+.}-{3:3}, at: set_nx_huge_pages+0x179/0x1e0 [kvm]
but task is already holding lock:
ffffffffc07abb08 (kvm_lock){+.+.}-{3:3}, at: set_nx_huge_pages+0x14a/0x1e0 [kvm]
which lock already depends on the new lock.
the existing dependency chain (in reverse order) is:
-> #3 (kvm_lock){+.+.}-{3:3}:
__mutex_lock+0x6a/0xb40
mutex_lock_nested+0x1f/0x30
kvm_dev_ioctl+0x4fb/0xe50 [kvm]
__se_sys_ioctl+0x7b/0xd0
__x64_sys_ioctl+0x21/0x30
x64_sys_call+0x15d0/0x2e60
do_syscall_64+0x83/0x160
entry_SYSCALL_64_after_hwframe+0x76/0x7e
-> #2 (cpu_hotplug_lock){++++}-{0:0}:
cpus_read_lock+0x2e/0xb0
static_key_slow_inc+0x16/0x30
kvm_lapic_set_base+0x6a/0x1c0 [kvm]
kvm_set_apic_base+0x8f/0xe0 [kvm]
kvm_set_msr_common+0x9ae/0xf80 [kvm]
vmx_set_msr+0xa54/0xbe0 [kvm_intel]
__kvm_set_msr+0xb6/0x1a0 [kvm]
kvm_arch_vcpu_ioctl+0xeca/0x10c0 [kvm]
kvm_vcpu_ioctl+0x485/0x5b0 [kvm]
__se_sys_ioctl+0x7b/0xd0
__x64_sys_ioctl+0x21/0x30
x64_sys_call+0x15d0/0x2e60
do_syscall_64+0x83/0x160
entry_SYSCALL_64_after_hwframe+0x76/0x7e
-> #1 (&kvm->srcu){.+.+}-{0:0}:
__synchronize_srcu+0x44/0x1a0
---truncated--- |
| In the Linux kernel, the following vulnerability has been resolved:
RISC-V: KVM: Don't zero-out PMU snapshot area before freeing data
With the latest Linux-6.11-rc3, the below NULL pointer crash is observed
when SBI PMU snapshot is enabled for the guest and the guest is forcefully
powered-off.
Unable to handle kernel NULL pointer dereference at virtual address 0000000000000508
Oops [#1]
Modules linked in: kvm
CPU: 0 UID: 0 PID: 61 Comm: term-poll Not tainted 6.11.0-rc3-00018-g44d7178dd77a #3
Hardware name: riscv-virtio,qemu (DT)
epc : __kvm_write_guest_page+0x94/0xa6 [kvm]
ra : __kvm_write_guest_page+0x54/0xa6 [kvm]
epc : ffffffff01590e98 ra : ffffffff01590e58 sp : ffff8f80001f39b0
gp : ffffffff81512a60 tp : ffffaf80024872c0 t0 : ffffaf800247e000
t1 : 00000000000007e0 t2 : 0000000000000000 s0 : ffff8f80001f39f0
s1 : 00007fff89ac4000 a0 : ffffffff015dd7e8 a1 : 0000000000000086
a2 : 0000000000000000 a3 : ffffaf8000000000 a4 : ffffaf80024882c0
a5 : 0000000000000000 a6 : ffffaf800328d780 a7 : 00000000000001cc
s2 : ffffaf800197bd00 s3 : 00000000000828c4 s4 : ffffaf800248c000
s5 : ffffaf800247d000 s6 : 0000000000001000 s7 : 0000000000001000
s8 : 0000000000000000 s9 : 00007fff861fd500 s10: 0000000000000001
s11: 0000000000800000 t3 : 00000000000004d3 t4 : 00000000000004d3
t5 : ffffffff814126e0 t6 : ffffffff81412700
status: 0000000200000120 badaddr: 0000000000000508 cause: 000000000000000d
[<ffffffff01590e98>] __kvm_write_guest_page+0x94/0xa6 [kvm]
[<ffffffff015943a6>] kvm_vcpu_write_guest+0x56/0x90 [kvm]
[<ffffffff015a175c>] kvm_pmu_clear_snapshot_area+0x42/0x7e [kvm]
[<ffffffff015a1972>] kvm_riscv_vcpu_pmu_deinit.part.0+0xe0/0x14e [kvm]
[<ffffffff015a2ad0>] kvm_riscv_vcpu_pmu_deinit+0x1a/0x24 [kvm]
[<ffffffff0159b344>] kvm_arch_vcpu_destroy+0x28/0x4c [kvm]
[<ffffffff0158e420>] kvm_destroy_vcpus+0x5a/0xda [kvm]
[<ffffffff0159930c>] kvm_arch_destroy_vm+0x14/0x28 [kvm]
[<ffffffff01593260>] kvm_destroy_vm+0x168/0x2a0 [kvm]
[<ffffffff015933d4>] kvm_put_kvm+0x3c/0x58 [kvm]
[<ffffffff01593412>] kvm_vm_release+0x22/0x2e [kvm]
Clearly, the kvm_vcpu_write_guest() function is crashing because it is
being called from kvm_pmu_clear_snapshot_area() upon guest tear down.
To address the above issue, simplify the kvm_pmu_clear_snapshot_area() to
not zero-out PMU snapshot area from kvm_pmu_clear_snapshot_area() because
the guest is anyway being tore down.
The kvm_pmu_clear_snapshot_area() is also called when guest changes
PMU snapshot area of a VCPU but even in this case the previous PMU
snaphsot area must not be zeroed-out because the guest might have
reclaimed the pervious PMU snapshot area for some other purpose. |
| In the Linux kernel, the following vulnerability has been resolved:
codetag: debug: mark codetags for poisoned page as empty
When PG_hwpoison pages are freed they are treated differently in
free_pages_prepare() and instead of being released they are isolated.
Page allocation tag counters are decremented at this point since the page
is considered not in use. Later on when such pages are released by
unpoison_memory(), the allocation tag counters will be decremented again
and the following warning gets reported:
[ 113.930443][ T3282] ------------[ cut here ]------------
[ 113.931105][ T3282] alloc_tag was not set
[ 113.931576][ T3282] WARNING: CPU: 2 PID: 3282 at ./include/linux/alloc_tag.h:130 pgalloc_tag_sub.part.66+0x154/0x164
[ 113.932866][ T3282] Modules linked in: hwpoison_inject fuse ip6t_rpfilter ip6t_REJECT nf_reject_ipv6 ipt_REJECT nf_reject_ipv4 xt_conntrack ebtable_nat ebtable_broute ip6table_nat ip6table_man4
[ 113.941638][ T3282] CPU: 2 UID: 0 PID: 3282 Comm: madvise11 Kdump: loaded Tainted: G W 6.11.0-rc4-dirty #18
[ 113.943003][ T3282] Tainted: [W]=WARN
[ 113.943453][ T3282] Hardware name: QEMU KVM Virtual Machine, BIOS unknown 2/2/2022
[ 113.944378][ T3282] pstate: 40400005 (nZcv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
[ 113.945319][ T3282] pc : pgalloc_tag_sub.part.66+0x154/0x164
[ 113.946016][ T3282] lr : pgalloc_tag_sub.part.66+0x154/0x164
[ 113.946706][ T3282] sp : ffff800087093a10
[ 113.947197][ T3282] x29: ffff800087093a10 x28: ffff0000d7a9d400 x27: ffff80008249f0a0
[ 113.948165][ T3282] x26: 0000000000000000 x25: ffff80008249f2b0 x24: 0000000000000000
[ 113.949134][ T3282] x23: 0000000000000001 x22: 0000000000000001 x21: 0000000000000000
[ 113.950597][ T3282] x20: ffff0000c08fcad8 x19: ffff80008251e000 x18: ffffffffffffffff
[ 113.952207][ T3282] x17: 0000000000000000 x16: 0000000000000000 x15: ffff800081746210
[ 113.953161][ T3282] x14: 0000000000000000 x13: 205d323832335420 x12: 5b5d353031313339
[ 113.954120][ T3282] x11: ffff800087093500 x10: 000000000000005d x9 : 00000000ffffffd0
[ 113.955078][ T3282] x8 : 7f7f7f7f7f7f7f7f x7 : ffff80008236ba90 x6 : c0000000ffff7fff
[ 113.956036][ T3282] x5 : ffff000b34bf4dc8 x4 : ffff8000820aba90 x3 : 0000000000000001
[ 113.956994][ T3282] x2 : ffff800ab320f000 x1 : 841d1e35ac932e00 x0 : 0000000000000000
[ 113.957962][ T3282] Call trace:
[ 113.958350][ T3282] pgalloc_tag_sub.part.66+0x154/0x164
[ 113.959000][ T3282] pgalloc_tag_sub+0x14/0x1c
[ 113.959539][ T3282] free_unref_page+0xf4/0x4b8
[ 113.960096][ T3282] __folio_put+0xd4/0x120
[ 113.960614][ T3282] folio_put+0x24/0x50
[ 113.961103][ T3282] unpoison_memory+0x4f0/0x5b0
[ 113.961678][ T3282] hwpoison_unpoison+0x30/0x48 [hwpoison_inject]
[ 113.962436][ T3282] simple_attr_write_xsigned.isra.34+0xec/0x1cc
[ 113.963183][ T3282] simple_attr_write+0x38/0x48
[ 113.963750][ T3282] debugfs_attr_write+0x54/0x80
[ 113.964330][ T3282] full_proxy_write+0x68/0x98
[ 113.964880][ T3282] vfs_write+0xdc/0x4d0
[ 113.965372][ T3282] ksys_write+0x78/0x100
[ 113.965875][ T3282] __arm64_sys_write+0x24/0x30
[ 113.966440][ T3282] invoke_syscall+0x7c/0x104
[ 113.966984][ T3282] el0_svc_common.constprop.1+0x88/0x104
[ 113.967652][ T3282] do_el0_svc+0x2c/0x38
[ 113.968893][ T3282] el0_svc+0x3c/0x1b8
[ 113.969379][ T3282] el0t_64_sync_handler+0x98/0xbc
[ 113.969980][ T3282] el0t_64_sync+0x19c/0x1a0
[ 113.970511][ T3282] ---[ end trace 0000000000000000 ]---
To fix this, clear the page tag reference after the page got isolated
and accounted for. |
