Newest CVEs

IDDescriptionSeverityUpdated
CVE-2026-89977In the Linux kernel, the following vulnerability has been resolved: accel/ethosu: check MMIO mapping errors in probe devm_platform_ioremap_resource() returns an error pointer when the register resource cannot be mapped. ethosu_probe() stores it and continues until initialization dereferences it through MMIO accessors. Return the mapping error before initializing the device.
medium
2026-09-16
CVE-2026-89976In the Linux kernel, the following vulnerability has been resolved: accel/ethosu: fix job completion fence cleanup ethosu_ioctl_submit_job() allocates done_fence before validating buffer handles. Errors after allocation call ethosu_job_err_cleanup(), which frees the job but leaks the uninitialized fence. A scheduler dependency error also lets ethosu_job_run() return before dma_fence_init(). Normal cleanup then passes a zeroed refcount to dma_fence_put(). Release done_fence in the common cleanup path and use dma_fence_was_initialized() to distinguish initialized fences from raw allocations. [robh: also fix goto]
medium
2026-09-16
CVE-2026-89975In the Linux kernel, the following vulnerability has been resolved: nvme-fabrics: fix DHCHAP secret leak on parse failure nvmf_parse_options() duplicates dhchap_secret and dhchap_ctrl_secret with match_strdup() before validating the DHHC-1: representation. If validation fails, the parser returns -EINVAL before the temporary string in p is assigned to opts->dhchap_secret or opts->dhchap_ctrl_secret. nvmf_create_ctrl() subsequently frees opts, but nvmf_free_options() cannot release the unassigned temporary string. Each rejected option therefore leaks one allocation. This is easy to miss because valid secrets transfer ownership to opts and are freed normally, while the malformed-secret path still returns the expected -EINVAL to userspace. With CONFIG_NVME_HOST_AUTH enabled, the leak is reachable before the required-option checks and transport lookup. No NVMe-oF target or working transport connection is required; for example, repeatedly writing dhchap_secret=BAD or dhchap_ctrl_secret=BAD to /dev/nvme-fabrics deterministically takes the leaking parse path. Free the temporary string before leaving both validation error paths. Use kfree_sensitive() because the copied option may contain secret material even when its representation is rejected, matching the sensitive cleanup used for stored DHCHAP secrets.
high
2026-09-16
CVE-2026-89974In the Linux kernel, the following vulnerability has been resolved: nvme-fc: fix double free of fabrics options when nvme_add_ctrl() fails nvmf_create_ctrl() owns the fabrics options and frees them whenever ->create_ctrl() returns an error, so a transport must not free them on its own error paths. nvme-fc tracks this by testing ctrl->ctrl.opts in nvme_fc_ctrl_free(), which requires nvme_fc_init_ctrl() to clear that pointer on every error exit. The coupling is implicit, and commit 1a9e218195a5 ("nvme: split device add from initialization") broke it by adding a second error exit. When nvme_add_ctrl() fails, nvme_fc_init_ctrl() jumps to out_put_ctrl:, past the "ctrl->ctrl.opts = NULL" that only sits on the fail_ctrl: path, so nvme_fc_ctrl_free() frees the options and nvmf_create_ctrl() frees them a second time: BUG: KASAN: slab-use-after-free in nvmf_free_options+0x30/0x190 nvmf_free_options+0x30/0x190 drivers/nvme/host/fabrics.c:1284 nvmf_create_ctrl drivers/nvme/host/fabrics.c:1374 [inline] Freed by task 5534: nvme_fc_ctrl_free drivers/nvme/host/fc.c:2374 [inline] nvme_fc_init_ctrl+0xe17/0x1450 drivers/nvme/host/fc.c:3605 nvme_add_ctrl() fails when dev_set_name() cannot allocate, so this is reachable under memory pressure or fault injection. Without KASAN the options are freed twice. Rather than clear the pointer on the second exit as well, derive ownership the way nvme-tcp, nvme-rdma and nvme-loop do, from list membership: their free_ctrl leaves the options alone unless the controller made it onto the transport list. The list cannot simply be populated on the success path as it is there. nvme-fc runs the initial connect synchronously via flush_delayed_work(), and the controller has to be reachable on rport->ctrl_list for the whole of it: nvme_fc_unregister_remoteport() needs to find it to signal connectivity loss, nvme_fc_match_disconn_ls() matches an incoming Disconnect Association LS against ctrl->association_id, which is only assigned during that window, nvme_fc_resume_controller() needs it on remoteport re-registration, and nvme_fc_existing_controller() uses it to reject a duplicate connect racing the one in flight. Keep the insertion where it is and add a fail_unlist: label, falling into fail_ctrl:, for the error paths that run after it. The earlier error paths never reach the insertion and keep using fail_ctrl: directly, so the list is only touched where the controller is actually on it. nvme_fc_ctrl_free() cannot use the plain "goto free_ctrl" the other transports use, because it still has to put_device(), release the rport reference and free the ida entry for resources taken before the insertion. Sample list_empty() under rport->lock instead. ctrl->ctrl.opts also stays valid for the whole teardown now. That is not the bug being fixed, but it removes some fragility around the old idiom: nvme_free_ctrl() calls nvme_auth_free() before ->free_ctrl(), and ctrl_max_dhchaps() dereferences ctrl->opts without a NULL check when ctrl->dhchap_ctxs is set, which nvme-fc permits since NVMF_ALLOWED_OPTS allows the dhchap options. The nvme sysfs attributes that dereference ctrl->opts, such as hostnqn and address, evaluate their is_visible() test once at device_add() time and stay readable until cdev_device_del().
high
2026-09-16
CVE-2026-89973In the Linux kernel, the following vulnerability has been resolved: nvme-tcp: check the data direction of a C2HData PDU nvme_tcp_handle_c2h_data() finds the request by command id and checks that it has a payload, but it does not check that the command asked for data to be read. A controller that answers a write command with C2HData therefore reaches nvme_tcp_recv_data(), where _copy_to_iter() hits WARN_ON_ONCE(i->data_source) and returns 0. The receive path turns that into -EFAULT and resets the controller. No data is copied, so this is not memory corruption. What a controller gets is a kernel warning it can raise at will, which is fatal on a host booted with panic_on_warn. The send path already knows the direction - it consults rq_data_dir() when it builds a command - and nvme_tcp_handle_r2t() checks the length and the offset of the request it names. The C2HData path does not check the direction at all. Reject a C2HData PDU whose command is not a read. Rejecting it fails the command and resets the controller, as the neighbouring check in this function does; what goes away is the warning. [ 6.885580] ------------[ cut here ]------------ [ 6.886457] WARNING: lib/iov_iter.c:193 at _copy_to_iter+0x289/0x1330, CPU#0: kworker/0:1H/71 [ 6.888137] CPU: 0 UID: 0 PID: 71 Comm: kworker/0:1H Not tainted 7.2.0-rc5-NVMETCP-gf5098b6bae76 #1 PREEMPT(lazy) [ 6.891165] Workqueue: nvme_tcp_wq nvme_tcp_io_work [ 6.891875] RIP: 0010:_copy_to_iter+0x289/0x1330 [ 6.903739] Call Trace: [ 6.904085] <TASK> [ 6.909254] __skb_datagram_iter+0x433/0x820 [ 6.911026] skb_copy_datagram_iter+0x37/0x120 [ 6.911622] nvme_tcp_recv_skb+0xa07/0x4320 [ 6.913378] __tcp_read_sock+0x1ab/0x810 [ 6.915788] nvme_tcp_try_recv+0x152/0x1e0 [ 6.918222] nvme_tcp_io_work+0x1e4/0x6c0 [ 6.926906] </TASK> [ 6.927226] ---[ end trace 0000000000000000 ]--- [ 6.927878] nvme nvme0: queue 1 failed to copy request 0x71 data [ 6.928709] nvme nvme0: receive failed: -14
high
2026-09-16
CVE-2026-89972In the Linux kernel, the following vulnerability has been resolved: nvme: add missing SRCU grace period in error path nvme_alloc_ns() error path at out_unlink_ns removes ns from the namespace head siblings list with list_del_rcu(&ns->siblings) but does not wait for SRCU readers before freeing the namespace struct. Multipath code iterates the head->list under srcu_read_lock() in nvme_find_path() and nvme_mpath_revalidate_paths(), so a concurrent reader can still hold a reference to ns when kfree(ns) runs. The normal removal path in nvme_ns_remove() correctly calls synchronize_srcu(&ns->head->srcu) after list_del_rcu() to wait for in-progress readers. Add the same grace period in the error path.
critical
2026-09-16
CVE-2026-89971In the Linux kernel, the following vulnerability has been resolved: nvme: skip the zoned limits update if the zone info query failed nvme_query_zone_info() returns either a negative errno or a positive NVMe status code, but nvme_update_ns_info_block() only tests for the negative case: ret = nvme_query_zone_info(ns, lbaf, &zi); if (ret < 0) goto out; If the device fails the Identify Namespace (I/O Command Set specific) command, or the Identify Controller command issued by nvme_set_max_append(), the positive status falls through and setup continues with the zero-initialized zone info. nvme_update_zone_info() then marks the queue zoned with chunk_sectors and ns->head->zsze set to zero. blk_validate_zoned_limits() does not check chunk_sectors, so the limits commit succeeds. blk_revalidate_disk_zones() does reject the zero zone size, but by then the limits are live and nothing rolls them back, so I/O keeps being submitted to a zoned queue with a zero zone size and disk_zone_no() shifts by ilog2(0): nvme0n1: Invalid non power of two zone size (0) UBSAN: shift-out-of-bounds in include/linux/blkdev.h:747:16 shift exponent -1 is negative disk_zone_no include/linux/blkdev.h:747 [inline] bio_straddles_zones include/linux/blkdev.h:1058 [inline] blk_zone_wplug_handle_write block/blk-zoned.c:1423 [inline] blk_zone_plug_bio.cold+0x25/0x1c8 block/blk-zoned.c:1605 blk_mq_submit_bio+0x18fb/0x2870 block/blk-mq.c:3196 submit_bh_wbc+0x575/0x740 fs/buffer.c:2824 __block_write_full_folio+0x728/0xdd0 fs/buffer.c:1933 Any device, firmware or NVMe-oF target that fails this one command reaches this. Skip the zoned limits update in that case, and log which of the two things happened: during a revalidation the queue keeps the zone geometry it was last validated with, and on a first scan the namespace is registered without zoned limits, so that it is still available as a handle for admin commands. Neither of the paths in nvme_query_zone_info() that return a positive status logs anything, so the failure would otherwise be silent. zi.zone_size is an exact indicator: every path that returns a positive status returns before it is assigned, and after that the only failure left is -ENODEV, which the caller already handles. Found by FuzzNvme.
high
2026-09-16
CVE-2026-89970In the Linux kernel, the following vulnerability has been resolved: nvmet-auth: Synchronize timeout work during SQ teardown nvmet_auth_sq_free() cancels auth_expired_work with cancel_delayed_work(). If the work has already started, cancellation does not wait for the callback. Transport teardown can consequently free or reuse the queue containing struct nvmet_sq while nvmet_auth_expired_work() still accesses that SQ. Add a teardown-specific helper that synchronously drains the delayed work before freeing authentication state, and use it from nvmet_sq_destroy(). Keep the non-synchronous helper for in-band authentication state cleanup, where the SQ owner remains alive.
critical
2026-09-16
CVE-2026-89969In the Linux kernel, the following vulnerability has been resolved: nvmet-tcp: fix out-of-bounds write when receiving an over-long PDU nvmet_tcp_try_recv_pdu() reads a PDU header into the fixed 128-byte queue->pdu union, then computes the remaining payload length as queue->left = hdr->hlen - queue->offset + hdgst; and reads that many more bytes into &queue->pdu + queue->offset, without ever bounding the result against sizeof(queue->pdu). A struct nvme_tcp_icreq_pdu is itself 128 bytes, exactly the size of the union. Once a header digest has been negotiated (hdgst = 4), a second ICReq passes the hlen == nvmet_tcp_pdu_size() check but yields queue->left = 128 - 8 + 4 = 124, so bytes 8..132 are written into the 128-byte buffer -- 4 bytes past its end, over queue->hdr_digest and queue->data_digest. Those bytes are attacker-controlled (an ICReq carries no digest), and the duplicate ICReq is only rejected later, after the overflow. A remote unauthenticated host can thus corrupt kernel memory adjacent to the receive buffer. Reject any PDU whose declared length would read past the end of queue->pdu before the second recv.
critical
2026-09-16
CVE-2026-89968In the Linux kernel, the following vulnerability has been resolved: nvmet-tcp: reject unsolicited H2CData PDUs nvmet_tcp_handle_h2c_data_pdu() accepts an H2CData PDU after only checking that its TTAG is a valid in-range command index and that the command's data buffers are mapped. It never checks that the target has actually solicited that data by sending an R2T for the command. A remote host can abuse this. It submits a write command that takes the R2T path and, before the target transmits the R2T, sends an H2CData PDU for that command's tag. The data completes the command early, and when the command then fails synchronously (e.g. a length mismatch caught by nvmet_check_transfer_len()), it is completed a second time. Each completion calls nvmet_tcp_queue_response(), so the same command is added to queue->resp_list twice while it is still linked; the second llist_add() makes the node point to itself (lentry->next == lentry). nvmet_tcp_process_resp_list() then walks that self-referential node and adds the command to resp_send_list twice. With CONFIG_DEBUG_LIST this trips the "list_add double add" check (kernel BUG); without it the loop never terminates and the nvmet_tcp workqueue wedges (soft-lockup). It is remotely triggerable and needs no authentication on an allow_any_host subsystem. Track whether an R2T has been transmitted for a command and reject an H2CData PDU that arrives before it. The flag is cleared on command reuse (nvmet_tcp_get_cmd() zeroes cmd->flags) and stays set across the multiple H2CData PDUs of a single solicited transfer.
high
2026-09-16
CVE-2026-89967In the Linux kernel, the following vulnerability has been resolved: mm/migrate_device: avoid out-of-bounds writes for compound folios migrate_device_range() and migrate_device_pfns() clear the entries following a compound folio so that the PFN arrays retain their page-granular representation. If a compound folio extends beyond the end of the caller-provided range, the loops clear all following folio entries without limiting them to the number of slots remaining in the npages-sized array, causing an out-of-bounds write. Do not proceed with a compound folio if its page-granular representation does not fit entirely in the remaining PFN array. If this happens, drop any reference and lock acquired for the folio, clear the remaining entries, and stop collecting. Observed with a KASAN x86 QEMU kernel using the HMM migrate_anon_huge_zero selftest. Closing /dev/hmm_dmirror0 after migrating an anonymous huge page to device memory exercises: dmirror_fops_release() -> dmirror_device_evict_chunk() -> migrate_device_range()
high
2026-09-16
CVE-2026-89966In the Linux kernel, the following vulnerability has been resolved: mm/hugetlb_cma: fix null nodemask dereference in hugetlb_cma_alloc_frozen_folio alloc_buddy_hugetlb_folio_with_mpol() can pass a NULL nodemask to alloc_fresh_hugetlb_folio() as a fallback to allocate from all nodes. If order is gigantic, alloc_fresh_hugetlb_folio() propagates the NULL nodemask down to hugetlb_cma_alloc_frozen_folio() via alloc_gigantic_frozen_folio(). Additionally, hugetlb_cma_alloc_frozen_folio() previously attempted allocation on hugetlb_cma[nid] without verifying if nid is included in the caller's nodemask. Adding a node_isset(nid, *nodemask) check ensures the initial preferred node allocation honors the memory policy / nodemask. However, hugetlb_cma_alloc_frozen_folio() dereferences the nodemask in node_isset(nid, *nodemask) and for_each_node_mask(node, *nodemask), leading to a null pointer dereference kernel panic when nodemask is NULL. Fix this by checking if nodemask is NULL in hugetlb_cma_alloc_frozen_folio() and defaulting it to cpuset_current_mems_allowed. Enclose the allocation attempts within the cpuset seqcount retry loop so that if the cpuset changes concurrently during allocation, the attempts are retried using the updated nodemask. This ensures that the initial node check and fallback loop safely honor the task's cpuset without violating cpuset constraints or causing NULL pointer dereferences or unexpected allocation failures. From a userspace perspective, this bug allows an unprivileged user to crash the kernel (trigger a panic) by requesting a gigantic hugepage allocation with MPOL_PREFERRED_MANY on a system where CMA is only configured on a subset of NUMA nodes. This can be reproduced by booting a VM with two NUMA nodes, restricting CMA to Node 1 (e.g., hugetlb_cma=1:1G default_hugepagesz=1G hugepagesz=1G hugepages=0), and running a program that allocates a 1GB hugepage area without reserving, restricts allocation to Node 0 using mbind() with MPOL_PREFERRED_MANY, and triggers a page fault: void *ptr = mmap(NULL, 1UL << 30, PROT_READ | PROT_WRITE, MAP_PRIVATE | MAP_ANONYMOUS | MAP_HUGETLB | MAP_HUGE_1GB | MAP_NORESERVE, -1, 0); unsigned long nodemask = 1; /* Node 0 */ mbind(ptr, 1UL << 30, MPOL_PREFERRED_MANY, &nodemask, sizeof(nodemask) * 8, 0); memset(ptr, 0, 1UL << 30); /* Trigger fault */ This results in a NULL pointer dereference: BUG: kernel NULL pointer dereference, address: 0000000000000000 #PF: supervisor read access in kernel mode #PF: error_code(0x0000) - not-present page Oops: Oops: 0000 [#1] SMP NOPTI RIP: 0010:hugetlb_cma_alloc_frozen_folio+0x75/0x120 Call Trace: <TASK> only_alloc_fresh_hugetlb_folio.isra.0+0x2c/0x160 alloc_surplus_hugetlb_folio+0x6d/0x100 alloc_hugetlb_folio+0x3c5/0x660 hugetlb_no_page+0x3d9/0x650
medium
2026-09-16
CVE-2026-89965In the Linux kernel, the following vulnerability has been resolved: nvdimm/btt: reject an arena whose nfree is below the lane count The BTT info block's nfree field, the number of reserve free blocks, is read from the medium without validation. btt_freelist_init() and btt_rtt_init() size the per-lane freelist[] and rtt[] arrays by nfree, but the I/O path indexes them by the lane from nd_region_acquire_lane(), which is bounded by nd_region->num_lanes (ND_MAX_LANES), not by nfree. A crafted or foreign arena whose nfree is below the lane count makes freelist[lane]/rtt[lane] run past the allocation: an out-of-bounds write. btt.rst documents the nlanes = min(nfree, num_cpus) invariant, which the code does not currently honor: num_lanes is ND_MAX_LANES regardless of nfree. Reject an arena whose nfree is below num_lanes at discovery, before the per-lane arrays are allocated, enforcing that invariant.
high
2026-09-16
CVE-2026-89964In the Linux kernel, the following vulnerability has been resolved: parisc: eisa: Fix infinite loop when parsing invalid IRQ value When an invalid value is passed via the "eisa_irq_edge=" kernel command line parameter (e.g. "eisa_irq_edge=16,5"), eisa_irq_setup() prints an error message and continues without advancing the current position. As a result the same invalid value is parsed again and again, causing an infinite loop while the kernel boots. Advance to the next comma-separated entry, or stop parsing when there is no next entry, before continuing so that the remaining entries are processed normally.
medium
2026-09-17
CVE-2026-89963In the Linux kernel, the following vulnerability has been resolved: powerpc/kexec_file: Fix null-ptr-def in extra size calculation A static Sashiko AI review identified a potential NULL pointer dereference in kexec_extra_fdt_size_ppc64(). On platforms without any reserved memory regions, get_reserved_memory_ranges() can return 0 while leaving 'rmem' unallocated as NULL. Passing it directly leads to a kernel panic when evaluating 'rmem->nr_ranges'. Add a NULL check for 'rmem' to prevent this crash.
medium
2026-09-16
CVE-2026-89962In the Linux kernel, the following vulnerability has been resolved: powerpc/kexec_file: Prevent kexec range truncation Sashiko AI review pointed out the following issue. The __merge_memory_ranges() function incorrectly handles overlapping memory ranges when merging them. Although sort_memory_ranges() sorts all ranges by their start address in ascending order beforehand, the merge logic remains defective in two ways: 1. It compares the current range's start against the previous element (i-1) instead of the running target index (idx) 2. It unconditionally overwrites 'ranges[idx].end' with 'ranges[i].end'. This logic flaw leads to critical memory truncation when a larger memory range completely subsumes subsequent smaller ranges. For example, consider a sorted input array with three ranges: Range A (idx=0): [0x1000 - 0x9000] Range B (i=1): [0x2000 - 0x5000] (completely inside Range A) Range C (i=2): [0x6000 - 0x8000] (completely inside Range A) 1. When i=1 (Range B): ranges[1].start (0x2000) <= ranges[0].end + 1 (0x9001) is TRUE. The code executes: ranges[0].end = ranges[1].end, which erroneously shrinks Range A's end from 0x9000 down to 0x5000. 2. When i=2 (Range C): ranges[2].start (0x6000) <= ranges[1].end + 1 (0x5001) is FALSE. The code falls into the else block, creating a broken new range. As a result, valid memory fragments [0x5001 - 0x5fff] and [0x8001 - 0x9000] are completely lost from the kexec exclude lists, potentially allowing the crash kernel to overwrite active memory, causing data corruption or crashes. Fix this by ensuring the start of the current range is compared against the end of the active merged range (idx), and use max() to safely prevent the outer boundary from being truncated.
high
2026-09-16
CVE-2026-89961In the Linux kernel, the following vulnerability has been resolved: powerpc/mm: fix wrong addr_pfn tracking in compound vmemmap population vmemmap_populate_compound_pages() uses addr_pfn to determine the PFN offset within a compound page and to decide whether the current vmemmap slot should be populated as a head page mapping or should reuse a tail page mapping. However, addr_pfn is advanced manually in parallel with addr. The loop itself progresses in vmemmap address space, so each PAGE_SIZE step in addr covers PAGE_SIZE / sizeof(struct page) struct page slots. Since addr_pfn is compared against nr_pages in data-PFN units, it should advance by the same number of PFNs. The existing manual increments do not match that and therefore do not reliably track the PFN corresponding to the current addr. As a result, pfn_offset can be computed from the wrong PFN and the code can make the head/tail decision for the wrong compound-page position. Fix this by deriving addr_pfn directly from the current vmemmap address instead of carrying it as loop state.
high
2026-09-16
CVE-2026-89960In the Linux kernel, the following vulnerability has been resolved: s390/vfio-ap: fix stale pqap_hook pointer on error in vfio_ap_mdev_set_kvm() In vfio_ap_mdev_set_kvm(), kvm->arch.crypto.pqap_hook is set to &matrix_mdev->pqap_hook before the update locks are acquired and the mdev list is checked for a conflicting assignment. If another mdev is already attached to the same KVM instance, the function returns -EPERM without restoring the hook pointer, leaving kvm->arch.crypto.pqap_hook pointing at the failing matrix_mdev instead of the mdev that legitimately owns the KVM. Since matrix_mdev->kvm is never set on this error path, vfio_ap_mdev_unset_kvm() will not clean up the hook when matrix_mdev is later closed. If matrix_mdev is subsequently freed, any PQAP instruction executed by the guest will dereference the stale pointer through pqap_hook_rwsem, resulting in a use-after-free. Since kvm->arch.crypto.pqap_hook is only set in the vfio_ap_mdev_set_kvm() function and is cleared in the vfio_ap_mdev_unset_kvm() function, a check for 'kvm->arch.crypto.pqap_hook != NULL' is all that is needed to determine whether it belongs to another mdev. This will alleviate the need to iterate the matrix_dev->mdev_list list to see if the kvm object is assigned to another mdev.This was introduced in v3 to alleviate the need to take the mdevs_lock while iterating the list; however, this did not prevent a potential race condition. The pqap_hook_rwsem(write) is now performed inside get_update_locks_for_kvm(), which is updated to acquire pqap_hook_rwsem(write) between kvm->lock and mdevs_lock. This ordering is consistent with the PQAP intercept path, which acquires pqap_hook_rwsem in read mode while srcu is held under vcpu->mutex, establishing the dependency: kvm->lock -> vcpu->mutex -> srcu -> pqap_hook_rwsem(read). The pqap_hook_rwsem is now released inside the release_update_locks_for_kvm(), which is updated to release pqap_hook_rwsem(write) between mdevs_lock and kvm->lock. Additionally, kvm_put_kvm() in vfio_ap_mdev_unset_kvm() is moved after release_update_locks_for_kvm(). Previously it was called while kvm->lock was held; if it were ever the last reference, kvm_destroy_vm() would run under kvm->lock, which would deadlock.
high
2026-09-16
CVE-2026-89959In the Linux kernel, the following vulnerability has been resolved: s390/vfio-ap: Fix control domain removal in vfio_ap_mdev_cfg_remove The vfio_ap_config_remove function uses the bitmap_andnot function to clear bits from the matrix_mdev->matrix.adm bitmap (specifies the control domains assigned to the mdev). This prevents the explicitly unplugged control domains from being removed the KVM guest. The bitmap_and function is used instead.
high
2026-09-16
CVE-2026-89958In the Linux kernel, the following vulnerability has been resolved: s390/vfio-ap: Fix dereference matrix_mdev->kvm without checking for NULL The ap_driver structure has two fields which are function pointers to callbacks: * .on_config_changed: called at the start of the AP bus scan function to notify the device driver that the host AP configuration has changed and the associated AP devices will be added or removed accordingly. This gives the implementor a chance to evaluate the configuration changes and respond to them before the associated devices are added or removed. * .on_scan_complete: Called at the end of the AP bus scan function to notify the device driver that the host AP configuration has changed and the AP devices have been added or removed accordingly. This gives the implementor the opportunity to respond to the changes after the associated devices are added or removed. These two callbacks are implemented in the vfio_ap device driver via the vfio_ap_on_cfg_changed and vfio_ap_on_scan_complete functions respectively. Within the call stack of these two callback functions the matrix_mdev->kvm->lock mutex is taken without checking whether matrix_mdev->kvm is NULL or not. If matrix_mdev->kvm has never been set, trying to take the lock will trigger a NULL pointer dereference. This patch adds checks for matrix_mdev->kvm == NULL before taking the matrix_mdev->kvm->lock mutex. Note that the matrix_mdev->kvm->lock mutex taken in the vfio_ap_mdev_hot_plug_config function is moved to the calling function along with the matrix_dev->mdevs_lock which is needed there to access the fields of the matrix_mdev. It makes little sense to make the change the check for matrix_mdev->kvm there before taking the kvm->lock mutex only to have to move it out via another patch, so it is done in this patch. It is important to make note of the following: 1. The matrix_dev->guests_lock is acquired at the start of both callback functions. This ensures that matrix_mdev will not be removed via the vfio_ap_mdev_remove function because it too takes matrix_dev_guests_lock before removing the object; so, matrix_mdev will be available for the duration of the callback functions. 2. The matrix_dev->mdevs_lock mutex must be taken in order to access fields within the matrix_mdev structure 3. matrix_mdev->kvm->lock mutex must be taken before the matrix_dev->mdevs_lock to prevent a lockdep splat. 4: The kvm->lock must be held while plugging the guest's AP configuration into its SIE state description via the vfio_ap_mdev_update_guest_apcb function. 5. The vfio_ap_mdev_update_guest_apcb checks matrix_mdev->kvm to verify it is not NULL before doing the hot plug of the guest's AP configuration.
high
2026-09-16
CVE-2026-89957In the Linux kernel, the following vulnerability has been resolved: s390/vfio-ap: Fix hot-unplug skipped when last AP adapter or domain removed The vfio_ap_mdev_hot_unplug_cfg() function uses the return value of bitmap_andnot() to determine whether the guest APCB needs to be updated. However, bitmap_andnot() returns false when the resulting destination bitmap is empty. This means that if the only adapter, domain or control domain assigned to an mdev is removed from the host's AP configuration, the bit is correctly cleared from the shadow APCB, but bitmap_andnot() returns false because the result is an empty bitmap. Consequently, do_hotplug remains 0 and vfio_ap_mdev_update_guest_apcb() is never called, leaving the KVM guest with stale hardware access to the unplugged AP devices. Fix this by replacing the bitmap_andnot() return value check with bitmap_intersects() to determine whether the shadow APCB actually overlaps with the removal mask. If there is an intersection, call bitmap_andnot() solely for its side effect of clearing the bits, then unconditionally set do_hotplug to trigger the guest APCB update.
high
2026-09-16
CVE-2026-89956In the Linux kernel, the following vulnerability has been resolved: s390/vfio-ap: Fix missing lock required to access list of ap_matrix_mdev objects In order to traverse or add/remove ap_matrix_mdev objects in the matrix_dev->mdev_list, the matrix_dev->guests_lock mutex must be held. There are two functions that access the list without holding the mutex: vfio_ap_mdev_probe function ~~~~~~~~~~~~~~~~~~~~~~~~~~~ The vfio_ap_mdev_probe function uses the matrix_dev->mdevs_lock mutex to guard the add of a newly created ap_matrix_mdev object to the matrix_dev->mdev_list. This mutex does not protect list access; its purpose is to guard against concurrent access to fields contained in an ap_matrix_mdev object. This could lead to kernel memory corruption or use-after-free if another mdev is created or removed concurrently. The adding of an ap_matrix_mdev object to matrix_dev->mdev_list is now guarded by the matrix_dev->guests_lock which is the correct way to protect against concurrent mdev_list access. Also removed the following two lines of code because the matrix_mdev is allocated via vfio_alloc_device macro which uses kzalloc, so req_trigger and cfg_chg_trigger are already zero-initialised when the struct is allocated before the call to vfio_register_emulated_iommu_dev. This prevents a window whereby these triggers are set to NULL after the device is exposed to userspace. matrix_mdev->req_trigger = NULL; matrix_mdev->cfg_chg_trigger = NULL; vfio_ap_mdev_for_queue function ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ The status_show function that supports display of the status attribute of the devices in /sys/bus/ap/devices calls the vfio_ap_mdev_for_queue function which iterates the matrix_dev->mdev_list to find the object representing the queue device whose status is to be displayed. In order to traverse this list, the matrix_dev->guests_lock mutex must be held. To fix this, the guests_lock mutex is taken prior to taking the matrix_dev->mdevs_lock mutex in the status_show function. It is taken there rather than the vfio_ap_mdev_for_queue function - where it is needed - because it must be taken prior to the mdevs_lock mutex in order to adhere to the proper locking order and prevent a lockdep splat; also because the mdevs_lock is needed there to access fields within the matrix_mdev object in that function. See the vfio-ap-locking.rst in the linux kernel tree.
high
2026-09-16
CVE-2026-89955In the Linux kernel, the following vulnerability has been resolved: s390/vfio-ap: Fix NULL deref in status_show() during queue probe When vfio_ap_mdev_probe_queue() creates the sysfs attribute group, the queue's driver data has not yet been set. A concurrent read of the 'status' attribute can therefore call dev_get_drvdata() and get NULL, which is then passed directly to vfio_ap_mdev_for_queue() where q->apqn is unconditionally dereferenced, causing a NULL pointer dereference. Fix this by acquiring the update locks before calling sysfs_create_group(). The status_show() function acquires guests_lock before reading the driver data, so any concurrent read will block until after dev_set_drvdata() has been called and the update locks are released. As a bonus, the APQN no longer needs to be read from the queue struct after allocation — it can be read directly from apdev before allocation and stored in a local variable, which is then assigned to q->apqn once the allocation succeeds.
medium
2026-09-16
CVE-2026-89954In the Linux kernel, the following vulnerability has been resolved: mtd: afs: validate v2 image info bounds The AFS v2 parser uses footer[8] to locate the image information block inside the current erase block, then uses the image information region_count to walk entries from a fixed local array. The footer offset and region count come from flash contents and are not checked against the erase block or the local image-info array before use. Reject v2 entries whose image information offset would underflow the erase block calculation, and reject region counts that cannot fit in the local image-info array before walking region entries.
high
2026-09-16
CVE-2026-89953In the Linux kernel, the following vulnerability has been resolved: mtd: mtdoops: free page bitmap when the backing MTD is removed mtdoops_notify_add() allocates oops_page_used when the configured MTD device is registered. mtdoops_notify_remove() detaches from that device but leaves the bitmap allocated. If the same MTD device is later registered again, the add path allocates a new bitmap and overwrites the old pointer, leaking one vmalloc allocation per remove/add cycle. This is only visible when the backing MTD device can disappear and be registered again while mtdoops remains loaded, so the usual static MTD case does not expose it. Free the bitmap after unregistering the dumper and flushing the pending workers, then clear the pointer and page count before a later attach can allocate fresh state. Clearing the pointer also keeps the module exit path from freeing the same bitmap a second time after a remove event.
medium
2026-09-16
CVE-2026-89952In the Linux kernel, the following vulnerability has been resolved: mtd: rawnand: validate ONFI extended parameter page sections nand_flash_detect_ext_param_page() allocates the length declared by the ONFI parameter page, then treats the data as a fixed header followed by variable-length sections. It reads that header and advances over sections without first proving that the fixed page and each current section fit in the allocation. Reject pages shorter than the fixed header, track the remaining variable area while walking sections, and require the ECC section to contain every field read from struct onfi_ext_ecc_info. Use device-scoped diagnostics that identify the malformed ONFI section.
high
2026-09-16
CVE-2026-89951In the Linux kernel, the following vulnerability has been resolved: batman-adv: fix stale receive device on merged fragments Fragment reassembly reuses the skb from the highest-numbered buffered fragment as the merged packet. When that fragment was received on a hard interface which is deleted before the chain completes, the merged skb can re-enter the receive path with a stale skb->dev and skb_iif. batadv_batman_skb_recv() passes such merged packets through the normal receive handlers again. DAT and bridge loop avoidance both derive the ARP header length from skb->dev, so they can dereference the freed net_device before the packet reaches the local mesh interface. Refresh the receive device metadata from the current receive device before running the packet handlers. This keeps internally reinjected merged fragments consistent with the normal receive path after hard interface teardown.
high
2026-09-16
CVE-2026-89950In the Linux kernel, the following vulnerability has been resolved: batman-adv: mcast: linearize skbuff for packet generation batadv_mcast_forw_packet() and batadv_mcast_forw_scrape() is not only called (indirectly) by the unsharing+linearizing batadv_recv_mcast_packet() handler. When it is called (indirectly) by batadv_mcast_forw_mcsend() then it will be unshared but not linearized. The SKB_LINEAR_ASSERT() can therefore cause a fatal BUG(). The linearization should happen during the expansion of the head because the scrape function can be hit already during the initial batadv_mcast_forw_mode() selection code: * batadv_interface_tx * batadv_mcast_forw_mode * batadv_mcast_forw_mode_by_count() * batadv_mcast_forw_push() -> calls batadv_mcast_forw_expand_head() before everything else * batadv_mcast_forw_push_tvlvs() * batadv_mcast_forw_push_dests() * batadv_mcast_forw_push_adjust_padding() * batadv_mcast_forw_scrape()
medium
2026-09-16
CVE-2026-89949In the Linux kernel, the following vulnerability has been resolved: batman-adv: dat: avoid unaligned fault in IP extraction Independent of the alignment of the ARP packet in the SKB, either the batadv_arp_ip_src or the batadv_arp_ip_dst will have an unaligned access (on HW without native unaligned read support). Use get_unaligned() to handle this properly on all architectures.
medium
2026-09-16
CVE-2026-89948In the Linux kernel, the following vulnerability has been resolved: batman-adv: bla: fix freeing of claims on meshif deletion When the mesh interface is getting deleted, then batadv_bla_del_backbone_claims() (via batadv_bla_purge_backbone_gw()) could make sure that all claims gets removed. But this function is only executed when bat_priv->bla.claim_hash is not NULL. And since batadv_bla_free() is always setting it to NULL before it is (indirectly) called, it was never actually executed. But the batadv_bla_purge_claims() -> batadv_handle_unclaim() is at the moment too fragile because the BLA code is not handling the rehashing in batadv_bla_update_orig_address(). The stored backbone address doesn't have to be the one actually used for the hash bucket selection during the initial adding of the backbone. The batadv_handle_unclaim() can therefore fail to find the respective backbone for the unclaim and then stop the deletion. But the actual backbone_gw object is not needed for the unclaim because all relevant information is always provided by the caller. And the check for the existence of the backbone_gw doesn't provide any additional security check for the deletion of a claim.
high
2026-09-16
CVE-2026-89947In the Linux kernel, the following vulnerability has been resolved: clk: meson: align gxbb_32k_clk_sel number of parents with actual count The following out-of-bounds read has been observed by Christian on a GXBB WeTek Hub: ================================================================== BUG: KASAN: global-out-of-bounds in __clk_register+0x1b70/0x2418 Read of size 8 at addr ffffd66320cf88e0 by task swapper/0/1 CPU: 0 UID: 0 PID: 1 Comm: swapper/0 Not tainted 7.0.0-rc5 #1 PREEMPT Hardware name: WeTek Hub (DT) Call trace: show_stack+0x14/0x20 (C) dump_stack_lvl+0x74/0x94 print_report+0x164/0x4b0 kasan_report+0x98/0xd8 __asan_report_load8_noabort+0x1c/0x24 __clk_register+0x1b70/0x2418 devm_clk_hw_register+0x74/0x15c meson_clkc_init+0xd4/0x20c meson_clkc_syscon_probe+0x5c/0x94 platform_probe+0xbc/0x17c really_probe+0x184/0x844 __driver_probe_device+0x154/0x35c driver_probe_device+0x60/0x188 __driver_attach+0x168/0x4a0 bus_for_each_dev+0xec/0x180 driver_attach+0x38/0x58 bus_add_driver+0x238/0x4c0 driver_register+0x150/0x388 __platform_driver_register+0x54/0x7c gxbb_clkc_driver_init+0x18/0x20 do_one_initcall+0xb8/0x340 kernel_init_freeable+0x49c/0x52c kernel_init+0x24/0x148 ret_from_fork+0x10/0x20 The buggy address belongs to the variable: gxbb_32k_clk_parents+0x60/0x400 The buggy address belongs to a vmalloc virtual mapping The buggy address belongs to the physical page: Memory state around the buggy address: ffffd66320cf8780: 00 00 00 00 f9 f9 f9 f9 00 f9 f9 f9 f9 f9 f9 f9 ffffd66320cf8800: 00 04 f9 f9 f9 f9 f9 f9 00 04 f9 f9 f9 f9 f9 f9 >ffffd66320cf8880: 00 00 00 00 00 00 00 00 00 00 00 00 f9 f9 f9 f9 ^ ffffd66320cf8900: 00 01 f9 f9 f9 f9 f9 f9 00 06 f9 f9 f9 f9 f9 f9 ffffd66320cf8980: 00 00 02 f9 f9 f9 f9 f9 00 00 02 f9 f9 f9 f9 f9 ================================================================== Commit 7915d7d5407c ("clk: amlogic: gxbb: drop non existing 32k clock parent") dropped a non-existing clock parent from the gxbb_32k_clk_sel mux but didn't adjust the hard-coded num_parents field. Fix the actual number of parents of that mux by using ARRAY_SIZE instead (avoiding similar problems in future).
high
2026-09-16
CVE-2026-89946In the Linux kernel, the following vulnerability has been resolved: ASoC: cs35l33: drain threaded IRQ before runtime suspend cs35l33_runtime_suspend() currently switches the codec into regcache_cache_only(true) and powers it down without first quiescing the threaded IRQ registered by devm_request_threaded_irq(). That leaves a window where cs35l33_irq_thread() can still run after suspend has closed off live register access. A running system can reach this during runtime PM while the driver still has critical fault IRQs unmasked. If the threaded handler runs in that window, it reads volatile INT_STATUS_1/2 after cache_only has been enabled, ignores the regmap_read() failures, and can still drive the AMP_SHORT_RLS, CAL_ERR_RLS, OTE_RLS, and OTW_RLS release paths. Use disable_irq() before entering cache_only/power-off so any in-flight threaded handler is drained and no new IRQ thread can run during the suspended state. Re-enable the IRQ only after runtime_resume() has restored live register access with regcache_sync(). Since probe only warns if devm_request_threaded_irq() fails, track whether the IRQ was actually installed before disabling or re-enabling it.
medium
2026-09-16
CVE-2026-89945In the Linux kernel, the following vulnerability has been resolved: ASoC: cs35l34: drain threaded IRQ before runtime suspend cs35l34_runtime_suspend() currently switches the codec into regcache_cache_only(true), asserts reset low, and powers the device off without first quiescing the threaded IRQ registered by devm_request_threaded_irq(). That leaves a window where cs35l34_irq_thread() can still run after suspend has removed live hardware access. A running system can reach this during runtime PM while the driver still has critical fault IRQs unmasked. If the threaded handler runs in that window, it reads volatile INT_STATUS_1..4 after cache_only has been enabled, ignores the regmap_read() failures, and can still execute the PROT_RELEASE_CTL release sequence or the BST fault power-down writes. Use disable_irq() before entering cache_only/reset-low/power-off so any in-flight threaded handler is drained and no new IRQ thread can run while the device is suspended. Re-enable the IRQ only after runtime_resume() has restored live register access with regcache_sync(). Since probe only logs request_threaded_irq() failures and keeps going, track whether the IRQ was actually installed before disabling or re-enabling it.
medium
2026-09-16
CVE-2026-89944In the Linux kernel, the following vulnerability has been resolved: ASoC: hdac_hda: Fix hlink refcount leak on component registration failure hdac_hda_dev_probe() gets the HDA link with snd_hdac_ext_bus_link_get() before registering the ASoC component. If component registration fails, the function returns without dropping the link reference. Always call snd_hdac_ext_bus_link_put() after the registration attempt so the reference taken during probe is balanced on both success and failure.
medium
2026-09-16
CVE-2026-89943In the Linux kernel, the following vulnerability has been resolved: ASoC: loongson: Fix error handling in ACPI property parsing In loongson_card_parse_acpi(), the return value of device_property_read_string() for the `codec-dai-name` property was ignored. If the property is missing or invalid, an uninitialized pointer would be used later, potentially leading to undefined behavior. Fix this by checking the return value and propagating the error appropriately.
high
2026-09-16
CVE-2026-89942In the Linux kernel, the following vulnerability has been resolved: iio: buffer: Fix potential use-after-free in anonymous buffer release An anonymous buffer handle holds a reference to the underlying IIO device. The reference is dropped in the buffer handle's release function. If the device has been removed, either through unbind or hot-unplug, the buffer handle might hold the last reference. The release function takes the mutex for the buffer using a guard, which means the unlock happens after all the code in the function, including `iio_device_put()`. If the anonymous buffer holds the last reference this might free both the IIO device and the buffer, which contains the mutex, leading to use-after-free when the mutex is unlocked. Fix this by using a scoped guard just around the buffer dmabuf list access, making sure the mutex is unlocked before releasing the IIO device. Version 10 of the patch that introduced this issue used this exact scheme of first unlocking and then dropping the reference [1]. During review it was suggested to use a guard instead, and version 11 made that change [2].
high
2026-09-16
CVE-2026-89941In the Linux kernel, the following vulnerability has been resolved: iio: buffer: Make IIO DMA fence release RCU-safe The `dma_fence` documentation states that if a custom release implementation is provided, the `dma_fence` object must be freed in an RCU-safe way. The current `iio_dma_fence` implementation uses `kfree()`, which might result in a use-after-free. Remove the custom `release` implementation. This makes the DMA fence core fall back to `dma_fence_free()`, which calls `kfree_rcu()` on the fence. This requires that the fence be the first member of `struct iio_dma_fence`. Using the default release method for extended DMA fence structures is a common pattern.
high
2026-09-16
CVE-2026-89940In the Linux kernel, the following vulnerability has been resolved: iio: buffer: Tie IIO dma fence lock lifetime to the fence The `iio_dma_fence` implementation currently uses a lock embedded in the `iio_dmabuf_priv`. But the `iio_dma_fence` can outlive the `iio_dmabuf_priv`, which can cause a use-after-free. Tie the lifetime of the lock to the lifetime of the fence by embedding them in the same struct. We can't just hold a reference to the `iio_dmabuf_priv` from the `iio_dma_fence` since `iio_buffer_dmabuf_release()` might sleep and the fence release callback is not allowed to sleep. Note that the `dma_fence` framework now has an internal lock that gets used when the passing `NULL` for `lock` in `dma_fence_init()`, but in order to allow this patch to be backportable use an external lock.
high
2026-09-16
CVE-2026-89939In the Linux kernel, the following vulnerability has been resolved: iio: chemical: atlas-sensor: fix PM reference leak in buffer postenable atlas_buffer_postenable() acquires a runtime PM reference with pm_runtime_resume_and_get() but returns the result of atlas_set_interrupt() directly. If atlas_set_interrupt() fails, the runtime PM reference is leaked and the device can never autosuspend. Add pm_runtime_put_autosuspend() on the error path to balance the reference.
high
2026-09-16
CVE-2026-89938In the Linux kernel, the following vulnerability has been resolved: iio: chemical: atlas-sensor: use iio_trigger_poll_nested() to fix remove UAF The atlas driver requests its hardware data-ready IRQ with devm_request_threaded_irq(); its threaded handler queues an irq_work, atlas_work_handler(), that calls iio_trigger_poll(data->trig). The IRQ is devm-managed, so free_irq() runs from the devres unwind after atlas_remove() returns without flushing that irq_work. Once a buffer is enabled, conversion-complete IRQs keep firing and queueing it; a pending irq_work can therefore run after the unwind has freed atlas_data/indio_dev and the trigger, when atlas_work_handler() derives the atlas_data pointer via container_of() and dereferences data->trig, a use-after-free. Call iio_trigger_poll_nested() directly from the threaded handler instead of bouncing through irq_work. free_irq() then drains the threaded handler, closing the window; other iio drivers with a threaded data-ready IRQ do the same (e.g. bmi270). This issue was found by an in-house static analysis tool.
high
2026-09-16
CVE-2026-89937In the Linux kernel, the following vulnerability has been resolved: iio: chemical: sgp30: Handle IAQ thread creation failure kthread_run() can fail and return an error pointer, but sgp_probe() stores it and returns success, so the device is registered without its IAQ thread and sgp_remove() later passes the error pointer to kthread_stop(). Return the error from probe instead.
medium
2026-09-16
CVE-2026-89936In the Linux kernel, the following vulnerability has been resolved: iio: dac: m62332: Fix regulator reference count imbalance m62332_set_value() enables the Vcc regulator on every write of a non-zero value and disables it on every write of zero, without tracking the channel's current state. Because the regulator is reference counted, changing a channel directly from one non-zero value to another enables it more than once, while a later write of zero disables it only once. The reference count never returns to zero and the regulator is left enabled indefinitely. Only enable the regulator on the transition from zero to non-zero, and only disable it on the transition from non-zero to zero, using the previously stored channel value to detect the edge. Balance the regulator on the I2C error path so the reference count stays consistent if the write fails.
high
2026-09-16
CVE-2026-89935In the Linux kernel, the following vulnerability has been resolved: iio: light: apds9306: fix PM reference leak in apds9306_read_data() apds9306_read_data() calls pm_runtime_resume_and_get() but several error paths return directly without calling pm_runtime_put_autosuspend(), leaking the runtime PM reference and preventing the device from autosuspending. Use PM_RUNTIME_ACQUIRE_AUTOSUSPEND() and PM_RUNTIME_ACQUIRE_ERR() to automatically handle runtime PM reference release on all return paths.
high
2026-09-16
CVE-2026-89934In the Linux kernel, the following vulnerability has been resolved: iio: light: ltrf216a: fix runtime PM reference leak in error path ltrf216a_get_lux() acquires a runtime PM reference by calling ltrf216a_set_power_state(data, true). However, if ltrf216a_read_data() fails, the function returns immediately without dropping the reference. This leaves the runtime PM usage count unbalanced, preventing the device from autosuspending after a failed read. Fix this by releasing the runtime PM reference before returning from the error path.
medium
2026-09-16
CVE-2026-89933In the Linux kernel, the following vulnerability has been resolved: iio: pressure: dps310: fix NULL pointer dereference on ACPI probe When the device is enumerated through its ACPI HID (IFX3100), i2c_client_get_device_id() returns NULL: the ACPI-derived client name does not match the driver's i2c_device_id table. dps310_probe() then dereferences that NULL pointer in "iio->name = id->name" and crashes the kernel during probe. The IIO device name is always "dps310", so set it directly and drop the now-unused device-id lookup.
medium
2026-09-16
CVE-2026-89932In the Linux kernel, the following vulnerability has been resolved: KVM: nVMX: Always flush vpid02 on first use Make sure vpid02 is always flushed on first use by setting last_vpid=0 when allocating vpid02. nested_vmx_transition_tlb_flush() will always detect a VPID change on first VM-Enter after VMXON, because VPID=0 in vmcs12 is not allowed if L1 enables VPID. This avoids using stale TLB entries from a previous lifetime of the VPID, that might have been associated with a different vCPU (or a completely different VM). Note that last_vpid is already being initialized as 0 when the vCPU is created, but it is not reset when vpid02 is freed on VMXOFF. Hence, the problem can only occur if L1 does VMXOFF -> VMXON, runs an L2, and KVM happens to reuse a VPID that has TLB entries on the physical CPU.
high
2026-09-17
CVE-2026-89931In the Linux kernel, the following vulnerability has been resolved: KVM: nVMX: Ensure KVM_REQ_GET_NESTED_STATE_PAGES is cleared on VM-Exit Always check and clear KVM_REQ_GET_NESTED_STATE_PAGES when emulating a nested VM-Exit to ensure the request is cleared, even when KVM was built with CONFIG_KVM_HYPERV=n, as KVM subtly relies on the "check" to clear the flag and thus avoid double-mapping the vmcs12 pages, e.g. if KVM manages to bail from VM-Enter without processing the request, and then emulates VMLAUNCH or VMRESUME.
medium
2026-09-16
CVE-2026-89930In the Linux kernel, the following vulnerability has been resolved: KVM: nVMX: Service local TLB flushes on failed nested VM-Enter KVM services local TLB flushes on "full" nested VM-Exits (through __nested_vmx_vmexit()), but not if a nested VM-Enter fails (e.g. due to failed VMCS checks in nested_vmx_enter_non_root_mode()). However, it is possible that KVM had queued TLB flushes that need to be performed, even if the nested VM-Enter was not successful. For example, if VPID is disabled for L2 (via nested_vmx_transition_tlb_flush(), or if via the MSR load lists, as the SDM says: If any MSR is being loaded in such a way that would architecturally require a TLB flush, the TLBs are updated so that, after VM entry, the logical processor will not use any translations that were cached before the transition. The SDM is unclear about when the TLB flush should occur, and whether or not a failed VM entry would flush the TLB, so it is safer to always do the TLB flush in this case. More concretely, KVM also updates the last VPID L1 used for L2 in nested_vmx_transition_tlb_flush() (i.e. last_vpid), even if the VM entry ultimately fails. With the current code, KVM could miss a TLB flush if L1 changes L2's VPID, then does a failed VM entry followed by a successful one, as the failed VM entry would update last_vpid but not actually flush the TLB. Servicing local TLB flushes on failed VM entries makes sure that the TLB is always flushed when last_vpid is updated.
critical
2026-09-16
CVE-2026-89929In the Linux kernel, the following vulnerability has been resolved: KVM: nVM: Ensure INVVPID is emulated on the correct physical CPU When emulating INVVPID, KVM executes INVVPID on the physical CPU using vpid02 (instead of the L1 assigned VPID), after doing some validations on the operands. However, it is possible that the physical CPU KVM executes INVVPID on is different from the CPU L2 is running on. For example, in the following scenario: - L2 runs on CPU #1 and exits to L1 (vmx->nested.vmcs02.cpu=1) - L1 migrates to CPU #2 and executes INVVPID - KVM executes INVVPID on CPU #2 - L1 migrates back to CPU #1 and runs L2 (vmx->nested.vmcs02.cpu=1) The TLB entries on CPU #1 are never invalidated, because INVVPID was executed on CPU #2, and vmcs02 never ran on a different pCPU (i.e. vmx_vcpu_load_vmcs() will *not* request KVM_REQ_TLB_FLUSH). Ensure that INVVPID is being executed on the same pCPU that L2 last ran on, and if not, fallback to clearing last_vpid=0 to trigger a full VPID flush on the next nested VM-Enter (as KVM will detect L1 using a different VPID for L2). If L2 ends up running on a different pCPU, KVM will flush the TLB anyway through vmx_vcpu_load_vmcs().
high
2026-09-17
CVE-2026-89928In the Linux kernel, the following vulnerability has been resolved: KVM: x86/mmu: Consume the locked rmap value in the lockless rmap walk __kvm_rmap_lock() deliberately elides the rmap lock when it observes an empty rmap. In that case kvm_rmap_lock_readonly() also re-enables preemption and returns zero, so the caller holds neither the rmap lock nor a preemption reference. The elision documents the invariant it relies on: * Elide the lock if the rmap is empty, as lockless walkers (read-only * mode) don't need to (and can't) walk an empty rmap, nor can they add * entries to the rmap. I.e. the only paths that process empty rmaps * do so while holding mmu_lock for write, and are mutually exclusive. kvm_rmap_age_gfn_range() ignores the returned value and unconditionally enters for_each_rmap_spte_lockless(). The iterator started with rmap_get_first(), which re-reads rmap_head->val rather than using the value returned by the lock. If a writer populates the rmap between the lock's read and the iterator's re-read, the aging path walks the newly installed rmap without holding its lock. For a KVM_RMAP_MANY rmap this leaves the walker following a pte_list_desc chain that it never locked. A writer holding mmu_lock for write may free that chain (e.g. kvm_zap_all_rmap_sptes() on the recycle path, or any rmap zap) via kmem_cache_free() while the walk is in progress, giving a slab use-after-free. Nothing serialises the two: the aging path runs without mmu_lock when CONFIG_KVM_MMU_LOCKLESS_AGING=y, and the rmap lock that would otherwise exclude the writer was elided. Because the empty path re-enables preemption, the interval between the two reads can span an arbitrary scheduling delay. Fix the class of bug by having the lockless walk consume the value returned by the lock instead of re-reading the rmap. Split rmap_get_first() into __rmap_get_first(), which starts an iterator from an already-read rmap value, and make for_each_rmap_spte_lockless() take that value and call __rmap_get_first() directly. kvm_rmap_age_gfn_range() passes the value returned by kvm_rmap_lock_readonly(): when the lock was elided the value is zero, __rmap_get_first() returns NULL, and the walk is skipped. No lockless walker re-reads the rmap, so the lock-elision invariant cannot be violated, and no lock()-without-paired-unlock() path is added to the aging code.
high
2026-09-16