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Search Results (394986 CVEs found)

CVE Vendors Products Updated CVSS v3.1
CVE-2026-90101 1 Linux 1 Linux Kernel 2026-09-17 N/A
In the Linux kernel, the following vulnerability has been resolved: bnxt_en: Fix call to hardware monitoring event handler The first parameter of hwmon_notify_event() is supposed to be the hardware monitoring device. The bnxt driver calls it with the platform device as first parameter instead. This API break results in undefined behavior and may result in a crash. Pass the hardware monitoring device as parameter instead to fix the problem.
CVE-2026-90100 1 Linux 1 Linux Kernel 2026-09-17 N/A
In the Linux kernel, the following vulnerability has been resolved: ptp: netc: fix period truncation and potential divide-by-zero in PEROUT The max_period bound in net_timer_enable_perout() was computed as: max_period = (u64)NETC_TMR_DEFAULT_FIPER + integral_period; which exceeds U32_MAX when integral_period > 0 (e.g. 0x100000002 for the default 333333333 Hz clock). A period_ns that passes this check but exceeds U32_MAX is then silently truncated when stored into the u32 struct netc_pp::period field. A truncated value of zero can reach netc_timer_set_perout_alarm(), where the local u32 period variable would also be 0, causing a divide-by-zero in roundup_u64(delta, period) whenever the stime < min_time branch is taken (which always happens for a start time of {0, 0}). Additionally, netc_timer_enable_periodic_pulse() and netc_timer_enable_fiper() both compute: fiper = pp->period - integral_period; A zero pp->period results in an unsigned wraparound to 0xFFFFFFFD, mis-programming the FIPER hardware register. Fix all three issues by capping max_period at NETC_TMR_DEFAULT_FIPER (0xFFFFFFFF). This ensures that any period_ns passing the range check fits in a u32 without truncation, so the stored value is always valid and non-zero. The accepted range is reduced by integral_period ns (typically only a few nanoseconds), which is negligible in practice.
CVE-2026-90099 1 Linux 1 Linux Kernel 2026-09-17 N/A
In the Linux kernel, the following vulnerability has been resolved: net/sched: account classifier filter allocations to memcg Allocations in the tc classifier *_change() paths (filter objects, per-CPU counters, and per-filter aux data) use plain GFP_KERNEL without __GFP_ACCOUNT, allowing unprivileged users to pin kernel memory outside memcg charging. The shared tcf_exts_init_ex() action array allocation in cls_api.c was also uncharged; this patch closes it along with the per-classifier filter-object/percpu/aux allocations that remain unaccounted. Add GFP_KERNEL_ACCOUNT to: - the shared tcf_exts_init_ex() action array (cls_api.c), common to every filter of every classifier (32 pointers, 256 bytes); - the filter-object, per-CPU-counter, and per-filter aux allocations in cls_basic, cls_bpf, cls_cgroup, cls_flow, cls_flower, cls_fw, cls_matchall, cls_route and cls_u32; - the u32_init_knode() replace-path knode allocation (cls_u32.c), which allocates the same struct tc_u_knode + sel.keys on every replace of an existing knode and was missed by the create-path-only conversion. Also fix the cls_basic error path: basic_change() inserts fnew into the IDR before allocating the per-CPU counter. If alloc_percpu() fails the errout path kfree'd fnew without idr_remove, leaving a dangling pointer in the IDR. With GFP_KERNEL_ACCOUNT the percpu alloc becomes failable on demand (memcg at memory.max), making the dead path attacker-reachable and burning the handle permanently. Add the idr_remove on the percpu failure path, matching the basic_set_parms failure-path pattern. Note: vega@nebusec.ai provided a poc for basic_cls, but it was easy to extend to the other classifiers. Conditions to recreate the bug: - CONFIG_NET_SCHED, CONFIG_NET_CLS_* (the classifier being used), CONFIG_NET_CLS_ACT, CONFIG_MEMCG, CONFIG_USER_NS, CONFIG_NET_NS. - Unprivileged user in a fresh user+network namespace (unshare -Urn), or root with CAP_NET_ADMIN. - Create a large number of tc filters (e.g. tc filter add dev lo ingress ... <classifier> ...) while watching a memcg-limited cgroup: system slab grows far faster than memory.current, pinning kernel memory outside memcg charging.
CVE-2026-90098 1 Linux 1 Linux Kernel 2026-09-17 N/A
In the Linux kernel, the following vulnerability has been resolved: net: sparx5: fix sleep in atomic context in MAC table access sparx5_set_rx_mode() runs with netif_addr_lock_bh held and iterates dev->mc via __dev_mc_sync(), which per address calls sparx5_mc_sync() / sparx5_mc_unsync() -> sparx5_mact_learn() / sparx5_mact_forget(). These take sparx5->lock, a mutex, and then poll the MAC access command register with readx_poll_timeout(). A mutex may block, which is not allowed from atomic context. Convert the driver to the new .ndo_set_rx_mode_async callback introduced in commit 3554b4345d85 ("net: introduce ndo_set_rx_mode_async and netdev_rx_mode_work"). The async callback is invoked from process context, so the mutex and sleeping completion poll can remain. Observed with CONFIG_PROVE_LOCKING, CONFIG_DEBUG_SPINLOCK, CONFIG_DEBUG_MUTEXES and CONFIG_DEBUG_ATOMIC_SLEEP enabled: BUG: sleeping function called from invalid context at kernel/locking/mutex.c:591 in_atomic(): 1, irqs_disabled(): 0, non_block: 0, pid: 217, name: ip preempt_count: 201, expected: 0 Call trace: __might_resched+0x144/0x248 __might_sleep+0x48/0x7c __mutex_lock+0x74/0x850 mutex_lock_nested+0x24/0x30 sparx5_mact_learn+0x78/0x100 sparx5_mc_sync+0x40/0x54 __hw_addr_sync_dev+0xc4/0x170 sparx5_set_rx_mode+0x4c/0x58 __dev_set_rx_mode+0x64/0xa4 __dev_open+0x1ec/0x26c
CVE-2026-90097 1 Linux 1 Linux Kernel 2026-09-17 N/A
In the Linux kernel, the following vulnerability has been resolved: Drivers: hv: vmbus: Skip VMBus module cleanup for non-nested root partition The VMBus module initialization function, hv_acpi_init(), currently does nothing when running in the root partition and root is not nested in another VM. But the initialization function reports success, so the VMBus module is indeed loaded. VMBus functionality is not actually needed, but the VMBus module must be loaded so that hv_vmbus_exists() can answer correctly. Furthermore, the mshv_root dependency on the VMBus module is needed as described in the commit message for 840b740a35bf ("mshv: Add conditional VMBus dependency"). Loading the VMBus module without actually initializing it causes failures if the module should later be unloaded. The module unload code tries to clean up things that were never initialized, resulting in memory faults and a panic. Fix this by having VMBus module exit function perform the same check for non-nested root partition, and do nothing in such a case, just like hv_acpi_init(). In the long run, the code that manages the Hyper-V provided SynIC should be refactored to better coordinate the requirements of root partition scenarios and normal VM scenarios, and to hopefully remove the hv_vmbus_exists() dependnecy between mshv_root and VMBus modules. Preventing the current unload failure scenario is an expediency until such a refactoring is done.
CVE-2026-90096 1 Linux 1 Linux Kernel 2026-09-17 N/A
In the Linux kernel, the following vulnerability has been resolved: fuse: invalidate the correct range after O_APPEND direct write fuse_direct_write_iter() captures pos before generic_write_checks(), which moves ki_pos to EOF for O_APPEND writes: fuse_direct_write_iter() { pos = iocb->ki_pos; /* 0 (user-supplied) */ generic_write_checks(); /* ki_pos -> EOF */ fuse_direct_io(); /* writes at EOF, correct */ invalidate(pos, pos + res); /* [0, res) -- wrong */ } The post-write invalidation targets a stale range instead of the actual written range at EOF. This can cause data inconsistency when the file size is not page-aligned. The tail page straddling EOF has a valid portion before EOF that concurrent readers can fault back in during the DIO write window: Tail page (file size X not page-aligned): page_start X (EOF) page_end |--- valid data ----|-- stale --| CPU0 (O_APPEND DIO writer) CPU1 (buffered reader) -------------------------- ---------------------- invalidate [X, X+len) tail page evicted FUSE_WRITE in flight ... read [page_start, X) tail page re-faulted [X, page_end) = stale FUSE_WRITE completes i_size = X + len invalidate [0, len) <- WRONG tail page still cached read [X, X+len) hits stale tail page returns old data Fix by reading pos back from iocb->ki_pos after generic_write_checks(), as generic_file_direct_write() does. Also fix a typo in the comment ("may have" -> "may have competed").
CVE-2026-90095 1 Linux 1 Linux Kernel 2026-09-17 N/A
In the Linux kernel, the following vulnerability has been resolved: fuse: Fix the condition to enable over-io-uring The existing condition in fuse_uring_cmd() is there only to avoid disabling io-uring for connections that already run with it, missing was a condition to refuse any IORING_OP_URING_CMD if the connection/channel didn't get enabled because of missing FUSE_INIT reply flag FUSE_OVER_IO_URING. Without the reply flag the barrier in fuse_uring_ready() doesn't work and IO could already be going on and cause deadlock states (at a minimum one between fch->bg_lock and queue->lock). The change itself is trivial, but brings behavior change, FUSE_OVER_IO_URING has to be set in the FUSE_INIT_REPLY by fuse servers to accept any IORING_OP_URING_CMD. Libfuse does that and the only non-libfuse implementation I found (fractal-fuse) also does it. Qemu patches for fuse-io-uring are not merged yet, as far as I know. Moved up is the smp_load_acquire(&fch->initialized) check, as a fuse-server implementation might try to setup io-uring before FUSE_INIT is processed and might have gotten -EOPNOTSUPP instead of -EAGAIN. Also fixed is a stale comment that explains the handling of the FUSE_OVER_IO_URING flag in early RFC versions. If there should be a report from any library or application we probably need to revert this commit.
CVE-2026-90094 1 Linux 1 Linux Kernel 2026-09-17 N/A
In the Linux kernel, the following vulnerability has been resolved: arm64: process: Fix context switching MTE store-only tag check SCTLR_EL1.TCSO0 is set when user opt-in for MTE store-only tag check mode. However, it is not part of SCTLR_USER_MASK which imply that on context switch we never clear SCTLR_EL1.TCSO0, so we are leaking that setting into another task. Fix that by including SCTLR_EL1_TCSO0_MASK into SCTLR_USER_MASK
CVE-2026-90093 1 Linux 1 Linux Kernel 2026-09-17 N/A
In the Linux kernel, the following vulnerability has been resolved: Bluetooth: L2CAP: access chan->conn safely in get/setsockopt Since commit b66774b48dd9 ("Bluetooth: L2CAP: Fix UAF in channel timeout by holding conn ref") l2cap_chan::conn has held reference and remains non-NULL also after the corresponding hci_conn is deleted. In this state accessing various fields eg. hci_conn::hdev is invalid, which leads to KASAN crash in l2cap_sock_setsockopt() access of conn->hcon->hdev. Check l2cap_chan::conn.hcon corresponds to an alive hci_conn before trying to use it in l2cap_sock.c. Hold l2cap_chan_lock() in getsockopt/setsockopt to ensure it stays alive, and to avoid data races in l2cap_chan fields.
CVE-2026-90092 1 Linux 1 Linux Kernel 2026-09-17 N/A
In the Linux kernel, the following vulnerability has been resolved: Bluetooth: L2CAP: reject accept queue add unless BT_LISTEN New sk should not be added to parent socket accept queue after last l2cap_sock_cleanup_listen() has run in l2cap_sock_teardown_cb() and state set to BT_CLOSED, as that can result to UAF on dereferencing the dangling parent reference. l2cap_sock_new_connection_cb() may race with parent l2cap_chan teardown, due to chan->state accessed without consistent locking: [Task 1] [Task 2] l2cap_sock_release(parent) l2cap_connect l2cap_sock_shutdown pchan = l2cap_global_chan_by_psm l2cap_chan_lock(pchan) l2cap_chan_close l2cap_sock_teardown_cb pchan->state = BT_CLOSED l2cap_chan_unlock(pchan) ------> l2cap_chan_lock(pchan) l2cap_new_connection l2cap_sock_new_connection_cb l2cap_chan_lock(pchan) <-------- l2cap_chan_unlock(pchan) l2cap_sock_kill(parent) /* bt_sk(sk)->parent dangling */ Fix by adding check for sk_state == BT_LISTEN after acquiring sk lock in l2cap_sock_new_connection_cb(). Add lock_sock() around sk_state writes where missing, to avoid data races. Although the data races on pchan->state should be fixed too, this defensive sk_state check probably makes sense in any case.
CVE-2026-90091 1 Linux 1 Linux Kernel 2026-09-17 N/A
In the Linux kernel, the following vulnerability has been resolved: Bluetooth: L2CAP: fix race l2cap_sock_cleanup_listen() vs. put_chan For L2CAP sockets without owning sk->sk_socket, reading l2cap_pi(sk)->chan may race against concurrent l2cap_sock_kill() -> l2cap_sock_put_chan(). This excludes simultaneous proto_ops callbacks, but access in l2cap_sock_cleanup_listen() has unsafe lockless read. [Task 1] [Task 2 (hdev->workqueue)] l2cap_sock_release(parent) l2cap_disconn_cfm l2cap_sock_cleanup_listen l2cap_conn_del bt_accept_dequeue l2cap_chan_del lock_sock(sk) l2cap_sock_teardown_cb bt_accept_unlink bt_sk(sk)->parent = NULL release_sock(sk) ----------------> lock_sock(sk) parent = /* NULL */ lock_sock(sk) <--------------------- release_sock(sk) sock_set_flag(sk, SOCK_ZAPPED) l2cap_sock_close_cb l2cap_sock_kill(sk) l2cap_sock_put_chan chan = READ l2cap_pi(sk)->chan l2cap_pi(sk)->chan = NULL l2cap_chan_hold_unless_zero l2cap_put_chan(chan) kref_get_unless_zero(&chan->ref) Task 1 may observe NULL which causes null-ptr-deref. Fix the race by taking lock_sock() in l2cap_sock_kill() to synchronize with l2cap_sock_cleanup_listen(). hold_unless_zero() is not needed here, l2cap_pi(sk)->chan owns reference if it is non-NULL. Clarify code comments vs. locking.
CVE-2026-90090 1 Linux 1 Linux Kernel 2026-09-17 N/A
In the Linux kernel, the following vulnerability has been resolved: Bluetooth: btmtksdio: Fix out-of-bounds DMA read in the TX path btmtksdio_tx_packet() rounds the transfer size up to the SDIO block size of 256 bytes, but hands the host controller the SKB buffer as is: err = sdio_writesb(bdev->func, MTK_REG_CTDR, skb->data, round_up(skb->len, MTK_SDIO_BLOCK_SIZE)); Only skb->len bytes hold packet data, so the controller reads up to 255 bytes of uninitialised memory and sends it to the device over the SDIO bus. Depending on how much tailroom slack the SKB allocation happens to carry, that read can also extend past the end of the buffer. Compute the padded length up front, ensure the SKB has tailroom for it, and zero-fill the padding with skb_put_zero(). skb->len then covers the padding, so sdio_writesb() no longer needs to round up. byte_tx keeps counting the header and the payload only, and the error path restores the SKB so that the caller can requeue it. Writing behind skb->tail is only safe because the driver owns the buffer, which "Bluetooth: btmtksdio: Take exclusive ownership of the SKB before TX" ensures.
CVE-2026-90089 1 Linux 1 Linux Kernel 2026-09-17 N/A
In the Linux kernel, the following vulnerability has been resolved: Bluetooth: btnxpuart: Validate the FW dump header length nxp_process_fw_dump() pulls the ACL header off the frame and then reads seq_num and buf_len from a struct nxp_fw_dump_hdr placed at skb->data, without checking that the ACL payload is long enough to contain it. h4_recv_buf() collects HCI_ACL_HDR_SIZE bytes of header followed by the number of payload bytes named in that header, so skb->len is 4 + dlen with dlen supplied by the controller and possibly smaller than the 8 byte dump header, or zero. A short frame with connection handle 0xfff therefore reads both fields from beyond the received data. Beyond the read itself, buf_len is what terminates a dump: a value of zero makes the driver call hci_devcd_complete() and reset the controller, so a truncated frame can end a dump early. Use skb_pull_data() to validate and pull the FW dump header before accessing its fields. Warn and reject the chunk if the header is truncated.
CVE-2026-90088 1 Linux 1 Linux Kernel 2026-09-17 N/A
In the Linux kernel, the following vulnerability has been resolved: Bluetooth: RFCOMM: Validate MTU in rfcomm_apply_pn() to prevent infinite loop rfcomm_apply_pn() accepts the MTU value from a remote PN (Parameter Negotiation) frame without checking for zero. When the remote peer sends an MTU of zero, d->mtu is set to 0. This causes the sendmsg path to enter an infinite loop when fragmenting data, as each fragment has size == min_t(size_t, len, 0) == 0, so the remaining length never decreases. The infinite allocation of zero-length skbs exhausts all system memory. Fix by clamping d->mtu to RFCOMM_DEFAULT_MTU when the negotiated value is zero, consistent with the initial value assigned in rfcomm_dlc_alloc().
CVE-2026-90087 1 Linux 1 Linux Kernel 2026-09-17 N/A
In the Linux kernel, the following vulnerability has been resolved: Bluetooth: do not leak an hci_conn when a second LE connect is rejected create_le_conn_complete() decides whether the failed connection is still pending by comparing it against hci_lookup_le_connect(), which returns the first LE connection in BT_CONNECT. That is the same connection only while at most one is pending. Two can be pending. Connections created on the passive scan path sit in BT_CONNECT with HCI_CONN_SCANNING set and are invisible to hci_lookup_le_connect() until hci_le_create_conn_sync() clears the flag when their command is issued, so the -EBUSY guard in hci_connect_le() does not prevent a second connection from being queued while the first is still on the scan path. Whenever two connections are in BT_CONNECT at once, the lookup may return one connection while create_le_conn_complete() is reporting the failure of the other; the early exit then drops the error and hci_conn_failed() never runs on the connection that failed. The controller also rejects a second HCI_OP_LE_CREATE_CONN issued while another connection creation is still outstanding, per Core Spec Vol 4, Part E. The spec calls for Command Disallowed there; the bcm43438 observed here answers with an LMP/LL error code instead, which bt_to_errno() maps to the -EPROTO (-71) in the log below. The leaked connection stays in BT_CONNECT forever, and because hci_connect_le() refuses to dial while hci_lookup_le_connect() finds anything, every subsequent attempt to reach any peer fails with -EBUSY and no command reaches the controller at all. Seen on a bcm43438 with two BLE peers polled on the same interval (state 5 is BT_CONNECT; both handles are UNSET ones, allocated from the ida above HCI_CONN_HANDLE_MAX): Bluetooth: hci1: Opcode 0x2013 failed: -71 # hcitool con < LE 14:9C:EF:03:68:81 handle 3840 state 5 lm CENTRAL < LE C4:D3:6A:8C:B5:38 handle 3841 state 5 lm CENTRAL A btmon capture across the next ten minutes of connect attempts contains no HCI_OP_LE_CREATE_CONN at all; outgoing LE connections do not recover until the adapter is reset. With this change the same scenario fails the rejected connection cleanly and further connects to both peers go through. Ask about the connection itself instead of about the device.
CVE-2026-90086 1 Linux 1 Linux Kernel 2026-09-17 N/A
In the Linux kernel, the following vulnerability has been resolved: xsk: honor XDP_TX_METADATA in zero-copy path The zero-copy path reads TX metadata whenever the UMEM has metadata space, even if the descriptor does not set XDP_TX_METADATA. Pass descriptor options through the metadata helpers and ignore metadata unless the option is set. This does not fix the existing per-WQE metadata handling for mlx5 MPWQEs. Only the descriptor that starts a session passes through xsk_tx_metadata_request() and configures offload state shared by the batch. Metadata on descriptors joining an open session is therefore not validated and does not configure its requested offloads. In addition, a non-NULL metadata pointer from such a descriptor is treated as a timestamp completion request even when XDP_TXMD_FLAGS_TIMESTAMP is not set, so its metadata union can be overwritten with an unrequested timestamp. Fixing mixed metadata states within one MPWQE requires a separate change.
CVE-2026-90085 1 Linux 1 Linux Kernel 2026-09-17 N/A
In the Linux kernel, the following vulnerability has been resolved: octeontx2-af: fix NULL deref in NIX TM tree debugfs read path rvu_dbg_nix_tm_tree_display() dereferences pfvf->sq_ctx without checking whether the SQ context has been allocated. Reading /sys/kernel/debug/octeontx2/nix/tm_tree for a NIX LF whose transmit queues are not set up triggers a kernel oops. Guard the read path the same way rvu_dbg_nix_tm_tree_write() already does and return -EINVAL with a seq_file message when sq_ctx is NULL.
CVE-2026-90084 1 Linux 1 Linux Kernel 2026-09-17 N/A
In the Linux kernel, the following vulnerability has been resolved: octeontx2-vf: fix workqueue and netdev race in probe/remove Initialize the VF workqueue before register_netdev() so ndo_set_rx_mode does not queue work on a NULL workqueue. Unregister the netdev before destroying the workqueue, and add proper probe error cleanup.
CVE-2026-90083 1 Linux 1 Linux Kernel 2026-09-17 N/A
In the Linux kernel, the following vulnerability has been resolved: net/sched: act_ife: Only operate on Ethernet frames act_ife encapsulates/decapsulates the original Ethernet header and uses skb->dev->hard_header_len as the length of that header. That is only correct for Ethernet devices: on a device where hard_header_len does not match the L2 header that was actually pulled (PPP reports PPP_HDRLEN while nothing is stripped on ingress), the ingress skb_push()/skb_pull() use the wrong length and can hit skb_under_panic when headroom is tight. IFE is Ethernet-only by design - it builds an outer ethhdr, rewrites h_source/h_dest/h_proto, and calls eth_type_trans() on decode - so instead of trying to make the offsets work for arbitrary link types, simply drop packets that do not carry an Ethernet header. Checking skb->dev->type alone is not enough. We have to cater for a corner case where mirred can redirect an skb from a non-Ethernet device to an Ethernet one, and skb->dev then says nothing about the framing the skb actually has: an skb redirected from ppp0 reaches the target's ingress hook with mac_len 0 and no Ethernet header at all. So at ingress also require mac_len to be ETH_HLEN. On egress mac_len is not maintained, so the device type is all we have; a bogus redirect there yields a malformed frame rather than an out-of-bounds push, and it would be malformed with or without IFE. That corner case is not theoretical - redirecting from ppp0 into a veth that has an ife encode action on its ingress hook panics without this patch: skbuff: skb_under_panic: len:98 put:14 head:ffff88800e410000 data:ffff88800e40fff5 tail:0x57 end:0x640 dev:veth3 kernel BUG at net/core/skbuff.c:214! Call Trace: skb_push (net/core/skbuff.c:224 net/core/skbuff.c:2657) tcf_ife_act (net/sched/act_ife.c:829 net/sched/act_ife.c:874) tc_run (net/core/dev.c:4463) netif_receive_skb (net/core/dev.c:6463 net/core/dev.c:6522) tcf_mirred_to_dev (net/sched/act_mirred.c:248 net/sched/act_mirred.c:328) tcf_mirred_act (net/sched/act_mirred.c:489) tc_run (net/core/dev.c:4463) process_backlog (net/core/dev.c:6728) With Ethernet framing guaranteed, use ETH_HLEN instead of hard_header_len.
CVE-2026-90082 1 Linux 1 Linux Kernel 2026-09-17 N/A
In the Linux kernel, the following vulnerability has been resolved: net: mana: Cap MSI-X vectors to the device MSI-X table size mana_gd_query_max_resources() sizes gc->num_msix_usable from resp.max_msix and the CPU count, but never from the device MSI-X table. On a 1792 vCPU M-series VM that yields 1793 while the table has 1024 entries, and mana_gd_setup_remaining_irqs() then walks indices 1..1792, running off the end of the region mapped by msix_map_region(): BUG: unable to handle page fault for address: ff8e347f8b99800c RIP: 0010:msix_prepare_msi_desc+0x7a/0x90 RAX: 0000000000004000 RBX: ff4330cb164ea780 RCX: ff8e347f8b998000 Call Trace: <TASK> __msi_domain_alloc_irqs+0x13a/0x440 msi_domain_alloc_irq_at+0x149/0x1b0 mana_gd_setup+0x351/0x890 mana_gd_probe+0x274/0x390 </TASK> RAX is index 1024 * PCI_MSIX_ENTRY_SIZE, one entry past the table. msi_insert_desc() does range check the index, but only against the MSI domain hwsize, which matches the table only for devices on an MSI parent domain. With a global PCI/MSI domain hwsize is MSI_XA_DOMAIN_SIZE, so nothing bounds the request. Cap num_msix_usable with pci_msix_vec_count().