Search Results (22398 CVEs found)

CVE Vendors Products Updated CVSS v3.1
CVE-2026-72026 1 Linux 1 Linux Kernel 2026-08-17 5.5 Medium
In the Linux kernel, the following vulnerability has been resolved: irqchip/irq-riscv-imsic-early: Fix fwnode leak on state setup failure imsic_early_acpi_init() allocates a firmware node before setting up the IMSIC state. If imsic_setup_state() fails, the function returns without freeing the allocated fwnode. Free the fwnode and clear the global pointer on this error path, matching the cleanup already done when imsic_early_probe() fails. [ tglx: Use a common cleanup path instead of copying code around ]
CVE-2026-72017 1 Linux 1 Linux Kernel 2026-08-17 5.5 Medium
In the Linux kernel, the following vulnerability has been resolved: net: macb: drop in-flight Tx SKBs on close The MACB driver has since forever leaked the outgoing SKBs that have not yet been marked as completed. They live in queue->tx_skb which gets freed without remorse nor checking. macb_free_consistent() gets called in a few codepaths, but only close will trigger the added expressions. In macb_open() and macb_alloc_consistent() failure cases, queues' tx_skb just got allocated and are empty.
CVE-2026-72016 1 Linux 1 Linux Kernel 2026-08-17 5.5 Medium
In the Linux kernel, the following vulnerability has been resolved: cpu/hotplug: Fix NULL kobject warning in cpuhp_smt_enable() On arm64, when booting with `maxcpus` greater than the number of present CPUs (e.g., QEMU -smp cpus=4,maxcpus=8), some CPUs are marked as 'present' but have not yet been registered via register_cpu(). Consequently, the per-cpu device objects for these CPUs are not yet initialized. In cpuhp_smt_enable(), the code iterates over all present CPUs. Calling _cpu_up() for these unregistered CPUs eventually leads to sysfs_create_group() being called with a NULL kobject (or a kobject without a directory), triggering the following warning in fs/sysfs/group.c: WARNING: fs/sysfs/group.c:137 at internal_create_group+0x41c/0x4bc, CPU#2: sh/181 [...] Call trace: internal_create_group+0x41c/0x4bc (P) sysfs_create_group+0x18/0x24 topology_add_dev+0x1c/0x28 cpuhp_invoke_callback+0x104/0x20c __cpuhp_invoke_callback_range+0x94/0x11c _cpu_up+0x200/0x37c When booting with ACPI, arm64 smp_prepare_cpus() currently sets all enumerated CPUs as "present" regardless of their status in the MADT. This causes issues with SMT hotplug control. For instance, with QEMU's "-smp 4,maxcpus=8" configuration, the MADT GICC entries are populated as follows: 1. The first four CPUs: `Enabled` set but `Online Capable` not set. 2. The remaining four CPUs: `Online Capable` set but `Enabled` not set to support potential hot-plugging. Fix this by: 1. When booting with ACPI, checking the ACPI_MADT_ENABLED flag in the GICC entry before calling set_cpu_present() during SMP initialization. 2. Properly managing the present mask in acpi_map_cpu() and acpi_unmap_cpu() to support actual CPU hotplug events, This aligns with other architectures like x86 and LoongArch. 3. Update the arm64 CPU hotplug documentation to no longer state that all online-capable vCPUs are marked as present by the kernel at boot time. This ensures that only physically available or explicitly enabled CPUs are in the present mask, keeping the SMT control logic consistent with the actual hardware state.
CVE-2026-72015 1 Linux 1 Linux Kernel 2026-08-17 5.5 Medium
In the Linux kernel, the following vulnerability has been resolved: fs/resctrl: Fix double-add of pseudo-locked region's RMID to free list A pseudo-locked group's RMID is freed when it is created. On unmount rmdir_all_sub() unconditionally frees all RMID of all groups, resulting in a double-free of the pseudo-locked group's RMID. The consequence of this is that the original free results in the pseudo-locked group's RMID being added to the rmid_free_lru linked list and the second free then attempts to add the same RMID entry to the rmid_free_lru again. Do not double-free a pseudo-locked group's RMID.
CVE-2026-72013 1 Linux 1 Linux Kernel 2026-08-17 5.5 Medium
In the Linux kernel, the following vulnerability has been resolved: riscv: Prevent NULL pointer dereference in machine_kexec_prepare() A NULL pointer dereference issue is noticed in riscv's machine_kexec_prepare(), where image->segment[i].buf might be NULL and copied unchecked. The NULL buf comes from ima_add_kexec_buffer(), where kbuf is added by kexec_add_buffer(), but kbuf.buffer is NULL, then it is copied without a check in machine_kexec_prepare(): kexec_file_load -> kimage_file_alloc_init() -> kimage_file_prepare_segments() -> ima_add_kexec_buffer() -> kexec_add_buffer() -> machine_kexec_prepare() -> memcpy() Address this by adding a check before the data copy attempt.
CVE-2026-72006 1 Linux 1 Linux Kernel 2026-08-17 5.5 Medium
In the Linux kernel, the following vulnerability has been resolved: net/mlx5: free mlx5_st_idx_data on final dealloc Workloads that repeatedly allocate and release mkeys carrying TPH steering-tag hints (e.g. churning RDMA MRs) leak one struct mlx5_st_idx_data per cycle; kmemleak flags it as unreferenced and the kmalloc slab grows over time. When the last reference to an ST table entry is dropped, mlx5_st_dealloc_index() removed the entry from idx_xa but the backing mlx5_st_idx_data allocation was never freed. Free idx_data after the xa_erase() so the lifetime of the bookkeeping struct matches the lifetime of the ST entry it tracks.
CVE-2026-68475 1 Linux 1 Linux Kernel 2026-08-17 5.5 Medium
In the Linux kernel, the following vulnerability has been resolved: reset: sunxi: fix memory region leak on ioremap failure In sunxi_reset_init(), when ioremap() fails, the memory region obtained via request_mem_region() is not released, leading to a resource leak. Add an err_mem_region label to properly release the memory region before freeing the data structure.
CVE-2026-68469 1 Linux 1 Linux Kernel 2026-08-17 5.5 Medium
In the Linux kernel, the following vulnerability has been resolved: wifi: mwifiex: fix permanently busy scans after multiple roam iterations In order for the firmware to sleep, the driver has to confirm a previously received sleep request. The normal sequence of evets goes like this: EVENT_SLEEP -> adapter->ps_state = PS_STATE_PRE_SLEEP -> sleep-confirm -> SLEEP -> EVENT_AWAKE -> AWAKE. Before sending the sleep-confirm command, the driver must make sure there are no commands either running or waiting to be completed. mwifiex_ret_802_11_associate() unconditionally sets ps_state = PS_STATE_AWAKE when it processes the association command response, outside of the normal powersave management flow. If EVENT_SLEEP arrives while the association command is in flight, ps_state is PRE_SLEEP when the association command response is parsed, and the forced AWAKE overwrites it. The deferred sleep-confirm is never sent. A subsequent scan_start command is correctly acknowledged, but the firmware doesn't generate scan_result events. The scan request never finishes, and additional requests from userspace fail with -EBUSY. After testing on both IW412 and W8997, I could only trigger the bug on the IW412 and observed the firmwares behave differently. On the IW412 the firmware still sends EVENT_SLEEP while the authentication / association process is ongoing. A W8997 under the same conditions seems to suppress power-save for the duration of the association, so PRE_SLEEP never coincided with the association response even after extended periods of testing using the loops described below (>12hours). On the IW412, the delay between commands that triggers an EVENT_SLEEP was empirically determined to be ~20ms. This delay can naturally occur when the driver is outputting debugging information (debug_mask = 0x00000037), in which situation the busy scans issue is repeatable while running "test 1)" as described below. If the delay between commands is less than ~20ms, the firmware stays awake and the issue was not reproducible running the same test. The host_mlme=false path also behaves differently. In this case, the entire authentication / association transaction is executed by one command (HostCmd_CMD_802_11_ASSOCIATE), and the firmware doesn't emit EVENT_SLEEP while the command is running. Remove the assignment so the ps_state is only manipulated in the paths that are related to powersave event handling and on the main workqueue for correct sleep confirmation. The following loop tests were performed (with debugging output enabled): 1) force roaming between two AP's, one 5GHz and one 2.4GHz, same SSID. Use wpa_cli to trigger the roaming behavior, sleep 2s between iterations. 2) force a disconnection to AP 1 and a connection to AP 2, test scan. Use wpa_cli to trigger the connection changes, sleep 2s between iterations. Each test ran in each device for at least 3 hours.
CVE-2026-68468 1 Linux 1 Linux Kernel 2026-08-17 5.5 Medium
In the Linux kernel, the following vulnerability has been resolved: mtd: virt-concat: free duplicate generated name Every MTD registration runs mtd_virt_concat_create_join(). Once a virtual concat has already been registered, the function builds the same name again and takes the equal-name branch. That branch skips to the next item without freeing the newly allocated string. Free the temporary name before continuing.
CVE-2026-68464 1 Linux 1 Linux Kernel 2026-08-17 5.5 Medium
In the Linux kernel, the following vulnerability has been resolved: mmc: sdhci-esdhc-imx: disable irq during suspend to fix unhandled interrupt When using WIFI out-of-band wakeup, an "irq xxx: nobody cared" warning occurs. This happens because the usdhc interrupt is not disabled during system suspend when device_may_wakeup() returns false. The sequence of events leading to this issue: 1. System enters suspend without disabling usdhc interrupt (because device_may_wakeup() returns false for usdhc device) 2. WIFI out-of-band wakeup triggers system resume via GPIO interrupt 3. WIFI sends a Card interrupt before usdhc has fully resumed 4. usdhc is still in runtime suspend state and cannot handle the interrupt properly 5. The unhandled interrupt triggers "nobody cared" warning Fix this by unconditionally disabling the usdhc interrupt during suspend and re-enabling it during resume, regardless of the wakeup capability. This ensures no interrupts are processed during the suspend/resume transition.
CVE-2026-68460 1 Linux 1 Linux Kernel 2026-08-17 5.5 Medium
In the Linux kernel, the following vulnerability has been resolved: f2fs: fix potential deadlock in f2fs_balance_fs() When the f2fs filesystem space is nearly exhausted, we encounter deadlock issues as below: INFO: task A:1890 blocked for more than 120 seconds. Tainted: G O 6.12.41-g3fe07ddf05ab #1 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:A state:D stack:0 pid:1890 tgid:1626 ppid:1153 flags:0x00000204 Call trace: __switch_to+0xf4/0x158 __schedule+0x27c/0x908 schedule+0x3c/0x118 io_schedule+0x44/0x68 folio_wait_bit_common+0x174/0x370 folio_wait_bit+0x20/0x38 folio_wait_writeback+0x54/0xc8 truncate_inode_partial_folio+0x70/0x1e0 truncate_inode_pages_range+0x1b0/0x450 truncate_pagecache+0x54/0x88 f2fs_file_write_iter+0x3e8/0xb80 do_iter_readv_writev+0xf0/0x1e0 vfs_writev+0x138/0x2c8 do_writev+0x88/0x130 __arm64_sys_writev+0x28/0x40 invoke_syscall+0x50/0x120 el0_svc_common.constprop.0+0xc8/0xf0 do_el0_svc+0x24/0x38 el0_svc+0x30/0xf8 el0t_64_sync_handler+0x120/0x130 el0t_64_sync+0x190/0x198 INFO: task kworker/u8:11:2680853 blocked for more than 120 seconds. Tainted: G O 6.12.41-g3fe07ddf05ab #1 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/u8:11 state:D stack:0 pid:2680853 tgid:2680853 ppid:2 flags:0x00000208 Workqueue: writeback wb_workfn (flush-254:0) Call trace: __switch_to+0xf4/0x158 __schedule+0x27c/0x908 schedule+0x3c/0x118 io_schedule+0x44/0x68 folio_wait_bit_common+0x174/0x370 __filemap_get_folio+0x214/0x348 pagecache_get_page+0x20/0x70 f2fs_get_read_data_page+0x150/0x3e8 f2fs_get_lock_data_page+0x2c/0x160 move_data_page+0x50/0x478 do_garbage_collect+0xd38/0x1528 f2fs_gc+0x240/0x7e0 f2fs_balance_fs+0x1a0/0x208 f2fs_write_single_data_page+0x6e4/0x730 f2fs_write_cache_pages+0x378/0x9b0 f2fs_write_data_pages+0x2e4/0x388 do_writepages+0x8c/0x2c8 __writeback_single_inode+0x4c/0x498 writeback_sb_inodes+0x234/0x4a8 __writeback_inodes_wb+0x58/0x118 wb_writeback+0x2f8/0x3c0 wb_workfn+0x2c4/0x508 process_one_work+0x180/0x408 worker_thread+0x258/0x368 kthread+0x118/0x128 ret_from_fork+0x10/0x200 INFO: task kworker/u8:8:2641297 blocked for more than 120 seconds. Tainted: G O 6.12.41-g3fe07ddf05ab #1 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/u8:8 state:D stack:0 pid:2641297 tgid:2641297 ppid:2 flags:0x00000208 Workqueue: writeback wb_workfn (flush-254:0) Call trace: __switch_to+0xf4/0x158 __schedule+0x27c/0x908 rt_mutex_schedule+0x30/0x60 __rt_mutex_slowlock_locked.constprop.0+0x460/0x8a8 rwbase_write_lock+0x24c/0x378 down_write+0x1c/0x30 f2fs_balance_fs+0x184/0x208 f2fs_write_inode+0xf4/0x328 __writeback_single_inode+0x370/0x498 writeback_sb_inodes+0x234/0x4a8 __writeback_inodes_wb+0x58/0x118 wb_writeback+0x2f8/0x3c0 wb_workfn+0x2c4/0x508 process_one_work+0x180/0x408 worker_thread+0x258/0x368 kthread+0x118/0x128 ret_from_fork+0x10/0x20 INFO: task B:1902 blocked for more than 120 seconds. Tainted: G O 6.12.41-g3fe07ddf05ab #1 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:B state:D stack:0 pid:1902 tgid:1626 ppid:1153 flags:0x0000020c Call trace: __switch_to+0xf4/0x158 __schedule+0x27c/0x908 rt_mutex_schedule+0x30/0x60 __rt_mutex_slowlock_locked.constprop.0+0x460/0x8a8 rwbase_write_lock+0x24c/0x378 down_write+0x1c/0x30 f2fs_balance_fs+0x184/0x208 f2fs_map_blocks+0x94c/0x1110 f2fs_file_write_iter+0x228/0xb80 do_iter_readv_writev+0xf0/0x1e0 vfs_writev+0x138/0x2c8 do_writev+0x88/0x130 __arm64_sys_writev+0x28/0x40 invoke_syscall+0x50/0x120 el0_svc_common.constprop.0+0xc8/0xf0 do_el0_svc+0x24/0x38 el0_svc+0x30/0xf8 el0t_64_sync_handler+0x120/0x130 el0t_64_sync+0x190/0x198 INFO: task sync:2769849 blocked for more than 120 seconds. Tainted: G ---truncated---
CVE-2026-68459 1 Linux 1 Linux Kernel 2026-08-17 5.5 Medium
In the Linux kernel, the following vulnerability has been resolved: f2fs: fix potential deadlock in gc_merge path of f2fs_balance_fs() When we mount device w/ gc_merge mount option, we may suffer below potential deadlock: Kworker GC trehad Truncator - f2fs_write_cache_pages - f2fs_write_single_data_page - f2fs_do_write_data_page - folio_start_writeback --- set writeback flag on folio - f2fs_outplace_write_data : cached folio in internal bio cache - f2fs_balance_fs - wake_up(gc_thread) : wake up gc thread to run foreground GC - finish_wait(fggc_wq) : wait on the waitqueue --- wait on GC thread to finish the work - truncate_inode_pages_range - __filemap_get_folio(, FGP_LOCK) --- lock folio - truncate_inode_partial_folio - folio_wait_writeback --- wait on writeback being cleared - do_garbage_collect - move_data_page - f2fs_get_lock_data_folio - lock on folio --- blocked on folio's lock In order to avoid such deadlock, let's call below functions to commit cached bios in GC_MERGE path of f2fs_balance_fs() as the same as we did in NOGC_MERGE path. - f2fs_submit_merged_write(sbi, DATA); - f2fs_submit_all_merged_ipu_writes(sbi);
CVE-2026-68456 1 Linux 1 Linux Kernel 2026-08-17 5.5 Medium
In the Linux kernel, the following vulnerability has been resolved: usb: atm: ueagle-atm: wait for pre-firmware load in .disconnect() ueagle-atm uses the asynchronous request_firmware_nowait() in .probe(), but does not wait for its completion, not even in .disconnect(); so, if the device is unplugged meanwhile, its teardown runs concurrently with that. Even though this inconsistency is worth addressing on its own, it has also triggered several bug reports in syzbot over the years (some auto-closed) where the firmware sysfs fallback mechanism (CONFIG_FW_LOADER_USER_HELPER) creates a firmware subdirectory in the device directory during its removal, which might hit unexpected conditions in kernfs, apparently, depending at which point the add and remove operations raced. (See links.) The pattern is: usb ?-?: Direct firmware load for ueagle-atm/eagle?.fw failed with error -2 usb ?-?: Falling back to sysfs fallback for: ueagle-atm/eagle?.fw <ERROR> Call trace: ... kernfs_create_dir_ns sysfs_create_dir_ns create_dir kobject_add_internal kobject_add_varg kobject_add class_dir_create_and_add get_device_parent device_add fw_load_sysfs_fallback fw_load_from_user_helper firmware_fallback_sysfs _request_firmware request_firmware_work_func ... (Some variations are observed, after fw_load_sysfs_fallback(), e.g., [1].) While the kernfs side is being looked at, the ueagle-atm side can be fixed by waiting for the pre-firmware load in the .disconnect() handler. This change has a similar approach to previous work by Andrey Tsygunka [2] (wait_for_completion() in .disconnect()), but it is relatively different in design/implementation; using the Originally-by tag for credit assignment. This has been tested with: - synthetic reproducer to check the error path; - USB gadget (virtual device) to check the firmware upload path; - QEMU device emulator to check the device ID re-enumeration path; (The latter two were written by Claude; no other code/text in this commit.) Links (year first reported): 2025 https://syzbot.org/bug?extid=ce1e5a1b4e086b43e56d 2025 https://syzbot.org/bug?extid=9af8471255ac36e34fd4 2024 https://syzbot.org/bug?extid=306212936b13e520679d 2023 https://syzkaller.appspot.com/bug?extid=457452d30bcdda75ead2 2022 https://syzbot.org/bug?extid=782984d6f1701b526edb 2021 https://syzbot.org/bug?id=f3f221579f4ef7e9691281f3c6f56c05f83e8490 2021 https://syzbot.org/bug?id=84d86f0d71394829df6fc53daf6642c045983881 2021 https://syzbot.org/bug?id=3302dc1c0e2b9c94f2e8edb404eabc9267bc6f90 [1] https://syzkaller.appspot.com/bug?extid=457452d30bcdda75ead2 [2] https://lore.kernel.org/lkml/20250410093146.3776801-2-aitsygunka@yandex.ru/
CVE-2026-68101 1 Linux 1 Linux Kernel 2026-08-17 5.5 Medium
This CVE ID has been rejected or withdrawn by its CVE Numbering Authority.
CVE-2026-74557 1 Linux 1 Linux Kernel 2026-08-17 7.5 High
In the Linux kernel, the following vulnerability has been resolved: scsi: libiscsi: Fix stale-data leak into the SCSI sense buffer iscsi_scsi_cmd_rsp() copies the sense data of a SCSI Response from the target-supplied data segment. The segment carries a 2-byte sense length followed by the sense bytes, so it must hold 2 + senselen bytes, but the bounds check only requires datalen >= senselen: senselen = get_unaligned_be16(data); if (datalen < senselen) goto invalid_datalen; memcpy(sc->sense_buffer, data + 2, min_t(uint16_t, senselen, SCSI_SENSE_BUFFERSIZE)); A target that returns a SCSI Response whose datalen equals senselen (with senselen <= SCSI_SENSE_BUFFERSIZE) makes the memcpy() from data + 2 read up to two bytes past the received data. Those bytes are stale conn->data contents and end up in the command's sense buffer, which is returned to userspace. Account for the 2-byte sense length prefix in the check.
CVE-2026-74556 1 Linux 1 Linux Kernel 2026-08-17 9.8 Critical
In the Linux kernel, the following vulnerability has been resolved: scsi: libiscsi_tcp: Bound SCSI Response data segment to the connection buffer iscsi_tcp_hdr_dissect() receives the data segment of several PDU types into the fixed-size conn->data buffer, which is allocated for ISCSI_DEF_MAX_RECV_SEG_LEN (8192) bytes. For the LOGIN_RSP, TEXT_RSP, REJECT and ASYNC_EVENT opcodes the dissect path already rejects a PDU whose DataSegmentLength exceeds that buffer. The SCSI Command Response (ISCSI_OP_SCSI_CMD_RSP) path also copies its data segment (sense/response data) into conn->data via iscsi_tcp_data_recv_prep(), but it does so without the same check. The only upstream bound on in.datalen is conn->max_recv_dlength, the initiator's advertised MaxRecvDataSegmentLength, which is commonly negotiated well above 8192 (open-iscsi defaults to 262144). A target that returns a SCSI Response with a DataSegmentLength between 8193 and max_recv_dlength therefore overflows the 8192-byte conn->data buffer. Once the same bound applies, ISCSI_OP_SCSI_CMD_RSP is handled exactly like those responses: bound the data segment, receive it into conn->data when present, and otherwise complete the PDU with no data. Fold the opcode into that case group rather than duplicating the check.
CVE-2026-74551 1 Linux 1 Linux Kernel 2026-08-17 7.8 High
In the Linux kernel, the following vulnerability has been resolved: hwmon: (nzxt-smart2) DMA-align output buffer Sashiko reports: When send_output_report() calls hid_hw_output_report(), the underlying USB HID core calls usb_interrupt_msg() which maps this buffer directly for DMA. When the DMA mapping flushes or invalidates the cacheline, it will corrupt the adjacent variables (mutex, update_interval) that were modified concurrently by the CPU. This causes memory corruption due to cacheline sharing on non-coherent CPU architectures (such as ARM or MIPS). The DMA API debugging tool (CONFIG_DMA_API_DEBUG) will trigger runtime warnings for this violation. Any operation that triggers send_output_report() (like setting a fan speed or updating the interval) causes the USB DMA mapping. On systems with non-coherent caches, this structural bug causes immediate and deterministic memory corruption. Align the output buffer to ARCH_DMA_MINALIGN to fix the problem.
CVE-2026-74544 1 Linux 1 Linux Kernel 2026-08-17 7.8 High
In the Linux kernel, the following vulnerability has been resolved: net/sched: cls_u32: validate offshift to prevent shift-out-of-bounds u32_change() copies the user-provided tc_u32_sel.offshift (unsigned char, 0-255) into the kernel knode object without bounds validation. When a packet later hits u32_classify() with TC_U32_VAROFFSET set, it evaluates `ntohs(offmask & *data) >> offshift` where the left operand is a 16-bit value promoted to a 32-bit int. Any offshift >= 32 is undefined behavior per C11 6.5.7p3, triggerable by an unprivileged user via user/network namespaces. UBSAN: shift-out-of-bounds in net/sched/cls_u32.c:236:43 shift exponent 32 is too large for 32-bit type int Fix this by rejecting offshift >= 16 during filter creation in u32_change().
CVE-2026-74520 1 Linux 1 Linux Kernel 2026-08-17 8.8 High
In the Linux kernel, the following vulnerability has been resolved: iommu/iommufd: Fix IOPF group ownership UAF iopf_group_alloc() links each last-page IOPF group into the generic IOPF pending list before invoking the domain fault handler. iommufd_fault_iopf_handler() also queued an accepted group in the IOMMUFD deliver list without removing it from the generic pending list. When detach or HWPT replacement drops the device's IOPF reference count to zero, an IOMMU driver may call iopf_queue_remove_device(). That function responds to and frees groups through the generic pending list without removing the same groups from IOMMUFD's deliver list or response xarray. A later read, response, or cleanup can then access the freed group and cause a UAF. Fix this by dequeuing an accepted group from the generic pending list before IOMMUFD queues it for userspace response. Make iopf_group_response() send a response regardless of pending-list membership, so the dequeued group can still be completed by IOMMUFD.
CVE-2026-74516 1 Linux 1 Linux Kernel 2026-08-17 8.2 High
In the Linux kernel, the following vulnerability has been resolved: KVM: SVM: Update x2APIC MSR intercepts if AVIC is inhibited while L2 is active Always update x2APIC MSR intercepts for L1 when AVIC is deactivated, even if L2 is active and KVM is using a separate MSR bitmap to run L2. If AVIC is fully enabled prior to running L2, and is then inhibited while L2 is active (for a VM-scoped inhibit), then KVM will run L1 with AVIC disabled, but with x2APIC MSR intercepts disabled, i.e. will allow L1 to read most of the host's APIC state, send arbitrary interrupts, change task priority, and ultimately trivially DoS the host. E.g. sending a self-IPI in L1 on HYPERV_REENLIGHTENMENT_VECTOR, 0xee, with CONFIG_HYPERV=n in the host kernel as a "safe" PoC, yields: Spurious interrupt (vector 0xee) on CPU#425. Acked And hacking KVM to abuse kvm_set_posted_intr_wakeup_handler() to register a handler and WARN on POSTED_INTR_WAKEUP_VECTOR yields: ------------[ cut here ]------------ WARNING: arch/x86/kvm/svm/svm.c:5594 at pi_wakeup_handler+0x9/0x10 [kvm_amd], CPU#156: nested_x2apic_t/316940 CPU: 156 UID: 0 PID: 316940 Comm: nested_x2apic_t Tainted: G S U Tainted: [S]=CPU_OUT_OF_SPEC, [U]=USER Hardware name: Google Astoria-Turin/astoria, BIOS 0.20260209.0-0 02/09/2026 RIP: 0010:pi_wakeup_handler+0x9/0x10 [kvm_amd] Call Trace: <IRQ> sysvec_kvm_posted_intr_wakeup_ipi+0x64/0x80 </IRQ> <TASK> asm_sysvec_kvm_posted_intr_wakeup_ipi+0x1a/0x20 RIP: 0010:vcpu_run+0x1430/0x1e40 [kvm] kvm_arch_vcpu_ioctl_run+0x2c1/0x600 [kvm] kvm_vcpu_ioctl+0x580/0x6b0 [kvm] __se_sys_ioctl+0x6d/0xb0 do_syscall_64+0x10a/0x480 entry_SYSCALL_64_after_hwframe+0x4b/0x53 RIP: 0033:0x46ff4b </TASK> ---[ end trace 0000000000000000 ]---