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Search Results (394849 CVEs found)

CVE Vendors Products Updated CVSS v3.1
CVE-2026-90074 1 Linux 1 Linux Kernel 2026-09-17 N/A
In the Linux kernel, the following vulnerability has been resolved: net/sched: fq_pie: clamp default quantum to avoid signed overflow fq_pie_init() sets q->quantum = psched_mtu(qdisc_dev(sch)) without clamping. A device with a huge MTU (e.g. dummy with max_mtu == 0 accepting MTU 2147483634) makes psched_mtu() return 0x80000000, which overflows the signed flow->deficit to INT_MIN in fq_pie_qdisc_dequeue(), causing an infinite loop and soft lockup. Emulate fq_pie_policy which is already bounded to [1, 1 << 20]; clamp the default to [256, 1 << 20]. 256 matches fq_codel's floor and is a sane minimum for a DRR quantum. Conditions to recreate the bug: a device whose MTU (plus hard_header_len) wraps psched_mtu() into the sign bit (e.g. a dummy device with max_mtu == 0 accepting MTU 2147483634). Requires CAP_NET_ADMIN in a user namespace.
CVE-2026-90073 1 Linux 1 Linux Kernel 2026-09-17 N/A
In the Linux kernel, the following vulnerability has been resolved: net/sched: hhf: clamp quantum before hhf_change() to avoid overflow hhf_init() sets q->quantum = psched_mtu(qdisc_dev(sch)) with no overflow check. A device with a huge MTU (e.g. dummy with max_mtu == 0 accepting MTU 2147483634) makes weight * quantum overflow the signed deficit in hhf_dequeue(), spinning forever. Clamp q->quantum before hhf_change() so both the opt and !opt paths see a sane quantum. Without this, bare "tc qdisc add ... hhf" succeeds with a clamped quantum but "tc qdisc add ... hhf limit 1000" (any option present) fails with -EINVAL because hhf_change() re-validates the unclamped default (sch_hhf.c:559). 256 matches fq_codel's floor and is a sane minimum for a DRR quantum. Conditions to recreate the bug: a device whose MTU (plus hard_header_len) wraps psched_mtu() into the sign bit (e.g. a dummy device with max_mtu == 0 accepting MTU 2147483634). Requires CAP_NET_ADMIN in a user namespace.
CVE-2026-90072 1 Linux 1 Linux Kernel 2026-09-17 N/A
In the Linux kernel, the following vulnerability has been resolved: net/sched: sfq: clamp quantum to avoid signed overflow soft lockup sfq_init() sets q->quantum = psched_mtu(qdisc_dev(sch)) (unsigned). A device with a huge MTU (e.g. dummy with max_mtu == 0 accepting MTU 2147483634) makes psched_mtu() return 0x80000000, so slot->allot = INT_MIN and INT_MIN + INT_MIN toggles between INT_MIN and 0 forever, spinning sfq_dequeue() under the qdisc lock. Clamp the quantum to [256, 1 << 20] so the refill loop terminates. The lower bound also covers q->quantum == 0 (psched_mtu() returning 0), which spins sfq_dequeue() identically. sfq_change() already rejects a negative quantum, so only the init path was exposed. Conditions to recreate the bug: a device whose MTU (plus hard_header_len) wraps psched_mtu() into the sign bit (e.g. a dummy device with max_mtu == 0 accepting MTU 2147483634). Requires CAP_NET_ADMIN in a user namespace.
CVE-2026-90071 1 Linux 1 Linux Kernel 2026-09-17 N/A
In the Linux kernel, the following vulnerability has been resolved: net/sched: sch_teql: restore skb->dev on the slave failure path teql_master_xmit() sets skb->dev = slave before calling the slave's ndo_start_xmit(), but never restores it when that transmit fails. The skb then walks on to the next slave still pointing at the previous one. If a later slave has no resolved neighbour, teql_resolve() hands the skb to neigh_event_send(), which queues it on that neighbour's arp_queue with the stale skb->dev. skb->dev holds no reference, so deleting the previous slave frees the net_device while the skb is still queued. Whatever runs next on that skb - arp_error_report() on timeout, or neigh_direct_output() -> dev_queue_xmit() once the neighbour resolves - causes a UAF like the one below: BUG: KASAN: slab-use-after-free in __icmp_send (net/ipv4/icmp.c:914 (discriminator 2)) Read of size 4 at addr ffff888106e100b0 by task flood_packet/527 CPU: 0 UID: 0 PID: 527 Comm: flood_packet Not tainted 7.2.0-rc6-g594d90519502 #1 PREEMPT(lazy) Hardware name: QEMU Ubuntu 24.04 PC v2 (i440FX + PIIX, arch_caps fix, 1996), BIOS 1.16.3-debian-1.16.3-2 04/01/2014 Call Trace: <IRQ> dump_stack_lvl (lib/dump_stack.c:94 lib/dump_stack.c:120) print_report (mm/kasan/report.c:378 mm/kasan/report.c:482) ? __pfx__raw_spin_lock_irqsave (./include/asm-generic/qrwlock.h:122 (discriminator 4)) ? __icmp_send (net/ipv4/icmp.c:914 (discriminator 2)) kasan_report (mm/kasan/report.c:595) ? __icmp_send (net/ipv4/icmp.c:914 (discriminator 2)) __icmp_send (net/ipv4/icmp.c:914 (discriminator 2)) [...] ipv4_link_failure (net/ipv4/route.c:1251 net/ipv4/route.c:1258) ? __pfx_ipv4_link_failure (./include/linux/skbuff.h:4327) ? _raw_write_lock (./include/linux/instrumented.h:55 ./include/linux/atomic/atomic-instrumented.h:1301 ./include/asm-generic/qrwlock.h:98 ./include/linux/rwlock_api_smp.h:230 kernel/locking/spinlock.c:304) ? __pfx__raw_write_lock (kernel/locking/spinlock.c:175) arp_error_report (./include/net/dst.h:438 net/ipv4/arp.c:296) neigh_invalidate (net/core/neighbour.c:1077) neigh_timer_handler (net/core/neighbour.c:1169) [...] Allocated by task 505: kasan_save_stack (mm/kasan/common.c:57) kasan_save_track (mm/kasan/common.c:78) __kasan_kmalloc (mm/kasan/common.c:398 mm/kasan/common.c:415) __kvmalloc_node_noprof (./include/linux/kasan.h:263 mm/slub.c:5334 mm/slub.c:6905) alloc_netdev_mqs (net/core/dev.c:12055 (discriminator 2)) rtnl_create_link (net/core/rtnetlink.c:3721) rtnl_newlink (net/core/rtnetlink.c:3903 net/core/rtnetlink.c:4044 net/core/rtnetlink.c:4159) rtnetlink_rcv_msg (net/core/rtnetlink.c:7076) [...] Freed by task 536: kasan_save_stack (mm/kasan/common.c:57) kasan_save_track (mm/kasan/common.c:78) kasan_save_free_info (mm/kasan/generic.c:584) __kasan_slab_free (mm/kasan/common.c:253 mm/kasan/common.c:285) kfree (./include/linux/kasan.h:235 mm/slub.c:2677 mm/slub.c:6377 mm/slub.c:6692) device_release (drivers/base/core.c:2636) kobject_put (lib/kobject.c:689 lib/kobject.c:720 ./include/linux/kref.h:65 lib/kobject.c:737) netdev_run_todo (net/core/dev.c:11756) rtnl_dellink (net/core/rtnetlink.c:157 ./include/linux/rtnetlink.h:135 net/core/rtnetlink.c:3651) rtnetlink_rcv_msg (net/core/rtnetlink.c:7076) [...] Fix this by restoring skb->dev to the master at the end of each slave's iteration.
CVE-2026-90070 1 Linux 1 Linux Kernel 2026-09-17 N/A
In the Linux kernel, the following vulnerability has been resolved: tpm: st33zp24: Return zero on status read failure st33zp24_status() ignores the result of the transport read and returns data even when no byte was received. The I2C transport, for example, skips i2c_master_recv() when the register-select write is short or fails, leaving data uninitialized. The resulting stack value can be interpreted as TPM_STS flags and let status checks complete spuriously. The status callback cannot propagate a transport error. Return zero unless recv() reports exactly one byte. With no status bits set, callers retry or take their existing timeout or error path instead of acting on an invalid status value. This issue was found by a static analysis checker and confirmed by manual source review.
CVE-2026-90069 1 Linux 1 Linux Kernel 2026-09-17 N/A
In the Linux kernel, the following vulnerability has been resolved: crypto: acomp - allocate async request context when cloning ACOMP_REQUEST_ON_STACK() reserves only enough storage for the synchronous fallback. When an async implementation is selected, callers clone that stack request before retrying, but acomp_request_clone() currently copies only the stack-sized object. The clone therefore has no storage for the async provider request context, and providers such as QAT write past the allocation through acomp_request_ctx(). KASAN does report a slab OOB write. Allocate a zeroed clone large enough for the runtime acomp request size, copy only the bytes present in the source object, and preserve the existing fallback-on-allocation-failure behavior. Use the runtime reqsize because an implementation may adjust it during tfm initialization.
CVE-2026-90068 1 Linux 1 Linux Kernel 2026-09-17 N/A
In the Linux kernel, the following vulnerability has been resolved: ASoC: dapm: Fix off-by-one check on the second enum channel The snd_soc_dapm_put_enum_double() rejects item[0] once it reaches e->items, but it lets item[1] be equal to it. Both go on to snd_soc_enum_item_to_val(), which indexes e->values with no bound of its own, so an enum with a value table reads one element past the end. The indexing arrived with the MUX consolidation, which relaxed the item[1] check in the same hunk. The value MUX handler it deleted used >= there, and the snd_soc_put_enum_double() in soc-ops.c still does. Only adav80x pairs a value table with two shifts, and its second channel looks accidental, but the control does report two values. Writing three into it reads off the end of adav80x_mux_values. The core catches that only under CONFIG_SND_CTL_INPUT_VALIDATION, which defaults off.
CVE-2026-90067 1 Linux 1 Linux Kernel 2026-09-17 N/A
In the Linux kernel, the following vulnerability has been resolved: libceph: validate banner payload length When parsing the Ceph messenger v2 protocol banner, the `payload_len` field is decoded from the banner prefix. If a client sends a banner with a `payload_len` of 0, the kernel sets up a 0-length socket read. This violates an invariant in the state machine, triggering a warning in `populate_in_iter()`: ------------[ cut here ]------------ !iov_iter_count(&con->v2.in_iter) WARNING: net/ceph/messenger_v2.c:3129 at populate_in_iter net/ceph/messenger_v2.c:3129 [inline], CPU#1: kworker/1:3/5070 WARNING: net/ceph/messenger_v2.c:3129 at ceph_con_v2_try_read+0x6634/0x6810 net/ceph/messenger_v2.c:3159, CPU#1: kworker/1:3/5070 ... Call Trace: <TASK> ceph_con_workfn+0x1f5/0x14a0 net/ceph/messenger.c:1575 process_one_work kernel/workqueue.c:3322 [inline] process_scheduled_works+0xa8e/0x14e0 kernel/workqueue.c:3405 worker_thread+0xa47/0xfb0 kernel/workqueue.c:3486 kthread+0x388/0x470 kernel/kthread.c:436 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 </TASK> According to the msgr2 protocol specification, the banner payload is expected to contain at least two 64-bit integers (`server_feat` and `server_req_feat`). Therefore, `payload_len` must be at least 16 bytes. Fix this by adding a check in `process_banner_prefix()` to reject a `payload_len` smaller than 16 bytes. This prevents the 0-length read and correctly aborts the connection with a protocol error.
CVE-2026-90066 1 Linux 1 Linux Kernel 2026-09-17 N/A
In the Linux kernel, the following vulnerability has been resolved: samples/ftrace: Fix kthread_stop() on ERR_PTR in ftrace-direct-multi-modify ftrace_direct_multi_init() assigns kthread_run()'s return value to simple_tsk without an IS_ERR() check. When kthread_run() fails it returns ERR_PTR(-ENOMEM), but init still returns 0, so the module loads with simple_tsk holding an error pointer. On unload, ftrace_direct_multi_exit() then passes that ERR_PTR to kthread_stop(), leading to a null-pointer-dereference. Check the return value of kthread_run() with IS_ERR(); on failure, unregister the ftrace direct call and propagate the error code.
CVE-2026-90065 1 Linux 1 Linux Kernel 2026-09-17 N/A
In the Linux kernel, the following vulnerability has been resolved: net/smc: release the internal TCP sock on IPPROTO_SMC socket creation failure IPPROTO_SMC sockets create an internal TCP sock ("clcsock") from the proto->init hook. When socket creation fails after proto->init has run - e.g. a cgroup BPF program attached to BPF_CGROUP_INET_SOCK_CREATE denies the socket - sk_common_release() only invokes sk_prot->destroy if it is set, but neither smc_inet_prot nor smc_inet6_prot defines it, and smc_destruct() returns early unless sk_state is SMC_CLOSED. As a result, every failing socket(AF_INET, SOCK_STREAM, IPPROTO_SMC) call leaks one tcp_sock, so an unprivileged task able to attach a deny-all BPF_CGROUP_INET_SOCK_CREATE program to its own cgroup can grow kernel memory unboundedly. Add a .destroy hook to both protos that releases the clcsock via smc_clcsock_release(). smc_sk_init() hashes the sock into the smc hashinfo before the clcsock is created, and smc_diag dumps walk that hash dereferencing smc->clcsock without taking clcsock_release_lock, while sk_common_release() calls .destroy before .unhash. Unhash the sock before releasing the clcsock, as __smc_release() does, so a concurrent dump cannot observe the release; the second unhash in sk_common_release() is a no-op.
CVE-2026-90064 1 Linux 1 Linux Kernel 2026-09-17 N/A
In the Linux kernel, the following vulnerability has been resolved: drm/xe: Reject page faults from non-fault-mode scratch VMs Having scratch enabled does not make a VM capable of handling recoverable page faults. Allowing scratch VMs through the ASID lookup also admits dma-fence mode VMs. If such a VM faults on an already valid VMA, the handler reports success without fixing the fault, causing the GPU to retry indefinitely. Only allow fault-mode VMs through the ASID lookup. Fault-mode VMs using scratch remain supported, while faults from 3D VMs are rejected. (cherry picked from commit bfb24a06405b652d37831f3fb66b71d33a6605de)
CVE-2026-90063 1 Linux 1 Linux Kernel 2026-09-17 N/A
In the Linux kernel, the following vulnerability has been resolved: virtio-net: Ensure that TCP packets don't overflow gso_segs The user can specify any gso_size in a packet crafted with an AF_PACKET PACKET_VNET_HDR socket, even smaller than TCP_MIN_GSO_SIZE = 8. At the same time, GSO_MAX_SIZE = 8 * GSO_MAX_SEGS = 8 * 65535. When the user crafts a packet with gso_size < 8, there is a risk for partial GSO to overflow the 16-bit gso_segs field when dividing the SKB length by gso_size. Adjust gso_size of TCP packets to be at least TCP_MIN_GSO_SIZE = 8. Keep gso_size of UDP GSO packets, as gso_size=1 is valid and explicitly tested at tools/testing/selftests/net/tun.c:649.
CVE-2026-90062 1 Linux 1 Linux Kernel 2026-09-17 N/A
In the Linux kernel, the following vulnerability has been resolved: netfilter: nf_tables: move hardware offload step after building the chain blob Allocate the chain blob before the ruleset offload to reduce chances of entering an inconsistent state where the offloaded ruleset in the nic and the software ruleset differ.
CVE-2026-90061 1 Linux 1 Linux Kernel 2026-09-17 N/A
In the Linux kernel, the following vulnerability has been resolved: netfilter: nf_tables: skip double clone set expressions on element insert Both the dynset and newsetelem path clone the existing set expressions when setting set element expressions if no override expressions are provided. This results in a double clone, once to clone the template set expressions then another clone on the new element. Add a flag to annotate if userspace provides a override expression (ie. expression of the same type of the set but different configuration), otherwise borrow the existing expression from the set. Add conditionals to release expression iif they represent an override. Use this new override_exprs flag to dump the dynset expression override to userspace. This simplifies the existing logic and it also fixes a bug with the connlimit expression which results in a module refcount imbalance WARNING splat when resorting on the default set expressions.
CVE-2026-90060 1 Linux 1 Linux Kernel 2026-09-17 N/A
In the Linux kernel, the following vulnerability has been resolved: ALSA: control: Don't add invalid kcontrols to LED layer The kcontrol LED state layer tries to track the all associated kcontrol elements with naive assumptions that they are readable. But one can create a write-only element that has no get callback (even a user element can do it), and this may lead to a NULL dereference at the call chain of snd_ctl_led_notify(), as found by syzkaller. For avoiding the Oops, add a sanity check of the kcontrol's info and get callbacks, and just skip the invalid kcontrols before assigning the kctl to the LED layer.
CVE-2026-90059 1 Linux 1 Linux Kernel 2026-09-17 N/A
In the Linux kernel, the following vulnerability has been resolved: net: stmmac: restore NET_IP_ALIGN in the RX DMA offset Since the RX path was converted to zero-copy, the page pool page is handed to the stack directly as the skb head, and the offset the DMA engine writes at is what determines the alignment of the packet headers. Before the conversion the payload was copied into an skb obtained from napi_alloc_skb(), which reserves NET_SKB_PAD + NET_IP_ALIGN. The conversion moved the headroom into stmmac_rx_offset() but did not carry over NET_IP_ALIGN, so on architectures where NET_IP_ALIGN is 2 the IP header now lands misaligned: 64 (NET_SKB_PAD) + 14 (ethernet) + 20 (IP) = 98 Same for the XDP branch: 256 (XDP_PACKET_HEADROOM) + 14 (ethernet) + 20 (IP) = 290 On ARM32 this is fatal, because ldm and ldrd trap on unaligned addresses even when CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS is set. Any received echo request panics the machine, e.g: Unhandled fault: alignment exception (0x001) at 0x81873062 Internal error: : 1 [#1] SMP ARM Hardware name: Altera SOCFPGA Arria10 PC is at icmp_echo+0x38/0xa8 LR is at icmp_rcv+0x22c/0x370 Call trace: icmp_echo from icmp_rcv+0x22c/0x370 icmp_rcv from ip_protocol_deliver_rcu+0x2c/0x224 ip_protocol_deliver_rcu from ip_local_deliver+0xc8/0x1a0 ip_local_deliver from ip_sublist_rcv_finish+0x3c/0x50 ip_sublist_rcv_finish from ip_list_rcv_finish+0x110/0x118 ip_list_rcv_finish from ip_list_rcv+0xc8/0xdc ip_list_rcv from __netif_receive_skb_list_core+0x170/0x1c0 ... napi_complete_done from stmmac_napi_poll_rx+0xcb0/0x1030 Code: e24dd068 e59020a0 e28dc010 e0822001 (e8920003) Kernel panic - not syncing: Fatal exception in interrupt The faulting instruction is the ldm of *icmp_hdr(skb) in icmp_echo(). Fix by adding NET_IP_ALIGN back to the RX offset, which restores the alignment the stack used to get. Note that commit a955318fe67e ("stmmac: align RX buffers") made a similar change in 2021 and was reverted by commit 12d125b4574b ("stmmac: Revert "stmmac: align RX buffers"") because it caused packet corruption. That patch raised the offset from 0 without adjusting the buffer size accounting, so the DMA engine could arguably write past the end of the RX buffers, though this was never root caused. Commit df542f669307 ("net: stmmac: Switch to zero-copy in non-XDP RX path") since derives the page pool allocation from stmmac_rx_offset(), so the extra bytes are accounted for.
CVE-2026-90058 1 Linux 1 Linux Kernel 2026-09-17 N/A
In the Linux kernel, the following vulnerability has been resolved: net/sched: bound qdisc_pkt_len to prevent qdisc soft lockup qdisc_get_stab() accepts a user-supplied size table, and __qdisc_calculate_pkt_len() amplifies qdisc_pkt_len() through the overhead, the size-table data (u16), and size_log (up to STAB_SIZE_LOG_MAX). A crafted stab can therefore set qdisc_pkt_len() to ~1 GiB for an ordinary skb. Per-flow deficit schedulers such as DRR and ETS replenish one quantum per loop iteration; with a tiny quantum (1) they spin billions of times under the qdisc lock, producing a soft lockup / RCU stall as illustrated by vega@nebusec.ai. Cap the final qdisc_pkt_len() to QDISC_PKT_LEN_MAX so the size-table amplification cannot drive deficit schedulers into an unbounded loop. A legitimate size table (e.g. qfq's overhead 999999999, which is handled by dropping) is still accepted. Introduce cap QDISC_PKT_LEN_MAX (1 << 20) = 1 MiB which is well above any legitimate single-skb wire length: the largest current skb->len is GSO_MAX_SIZE (524280), and an ATM-style size table (53/48 cell tax) amplifies that to ~578 KB, both comfortably below 1 MiB. At the same time, 1 MiB bounds the deficit refill loop to ~1M iterations per packet with quantum=1, which completes in a few milliseconds well under the demonstrated softlockup threshold (~10^9 iterations). Conditions to recreate the bug: - CONFIG_NET_SCHED=y, CONFIG_NET_SCH_DRR=y (or CONFIG_NET_SCH_ETS=y). - Attach a DRR (or ETS) root qdisc with a crafted TCA_STAB that amplifies qdisc_pkt_len to ~1 GiB (e.g. size_log=15, data=[32768]). - Add a class with a tiny quantum of 1 and send one small packet; the deficit loop spins billions of times under the qdisc lock and trips the softlockup detector (panic with kernel.softlockup_panic=1). - Reachable as root or from an unprivileged user in a fresh user+net namespace (unshare -Urn) with namespace-local CAP_NET_ADMIN.
CVE-2026-90057 1 Linux 1 Linux Kernel 2026-09-17 N/A
In the Linux kernel, the following vulnerability has been resolved: slip: remove slip_hangup() to fix use-after-free in slip_receive_buf() Jaeyoung Chung and Eulgyu Kim reported a slab-use-after-free read in slip_receive_buf() when racing against tty hangup. tty_ldisc_hangup() calls ld->ops->hangup() while holding only a read lock on tty->ldisc_sem (via tty_ldisc_ref()). Because slip_hangup() simply called slip_close(), it ran concurrently with reader functions such as slip_receive_buf(). slip_close() unregisters and frees the net device and its private struct slip, causing concurrent reader threads in slip_receive_buf() to dereference freed memory. Line discipline close() is already guaranteed to be called under the write lock of tty->ldisc_sem during hangup processing (in tty_ldisc_reinit() or tty_ldisc_kill()). Remove slip_hangup() so teardown is serialized cleanly by slip_close().
CVE-2026-90056 1 Linux 1 Linux Kernel 2026-09-17 N/A
In the Linux kernel, the following vulnerability has been resolved: net: fec: only stop PTP if it was initialized fec_ptp_init() is only called when fep->bufdesc_ex is available. However, fec_probe() unconditionally calls fec_ptp_stop() on the failed_init path, and fec_drv_remove() unconditionally calls fec_ptp_stop() during device removal. Check fep->bufdesc_ex before calling fec_ptp_stop() in both paths to avoid stopping PTP when it was not initialized.
CVE-2026-90055 1 Linux 1 Linux Kernel 2026-09-17 N/A
In the Linux kernel, the following vulnerability has been resolved: usb: atm: usbatm: fix invalid ci_range initialization syzbot reported a shift-out-of-bounds in __vcc_connect(): UBSAN: shift-out-of-bounds in net/atm/common.c:382:32 shift exponent -1 is negative CPU: 0 UID: 0 PID: 5987 Comm: syz.0.18 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Compute Engine/Google Compute Engine, BIOS Google 08/05/2026 Call Trace: <TASK> dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120 ubsan_epilogue+0xa/0x30 lib/ubsan.c:233 __ubsan_handle_shift_out_of_bounds+0x36d/0x400 lib/ubsan.c:494 __vcc_connect+0x14b4/0x19c0 net/atm/common.c:382 vcc_connect+0x328/0x8f0 net/atm/common.c:498 pvc_bind+0x272/0x380 net/atm/pvc.c:52 __sys_bind+0x2e3/0x410 net/socket.c:1976 __x64_sys_bind+0x7a/0x90 net/socket.c:1979 ... ATM device ci_range fields (vpi_bits and vci_bits) represent the number of bits supported for VPI and VCI addressing on the device. net/atm/common.c directly uses these fields as bit shift counts: vpi >> dev->ci_range.vpi_bits vci >> dev->ci_range.vci_bits 1 << vcc->dev->ci_range.vpi_bits 1 << vcc->dev->ci_range.vci_bits usbatm_atm_init() sets ci_range.vpi_bits and ci_range.vci_bits to ATM_CI_MAX (-1), which is defined in <uapi/linux/atmdev.h> as a sentinel value for userspace ATM_SETCIRANGE requests, not a valid bit count. Shifting by -1 is undefined behavior and triggers UBSAN warnings. ATM UNI cell headers allow up to 8 bits for VPI (0..255) and 16 bits for VCI (0..65535). Initialize vpi_bits to 8 and vci_bits to 16, as done by solos-pci.