Vulnerabilidades do Linux Linux Kernel

In the Linux kernel, the following vulnerability has been resolved: accel/amdxdna: Fix potential NULL pointer dereference in context cleanup aie_destroy_context() is invoked during error handling in aie2_create_context(). However, aie_destroy_context() assumes that the context's mailbox channel pointer is non-NULL. If mailbox channel creation fails, the pointer remains NULL and calling aie_destroy_context() can lead to a NULL pointer dereference. In aie2_create_context(), replace aie_destroy_context() with a function which request firmware to remove the context created previously.

In the Linux kernel, the following vulnerability has been resolved: drm/panthor: Fix NULL pointer dereference on panthor_fw_unplug This patch removes the MCU halt and wait for halt procedures during panthor_fw_unplug() as the MCU can be in a variety of states or the FW may not even be loaded/initialized at all, the latter of which can lead to a NULL pointer dereference. It should be safe on unplug to just disable the MCU without waiting for it to halt as it may not be able to.

In the Linux kernel, the following vulnerability has been resolved: drm/display/dp_mst: Add protection against 0 vcpi When releasing a timeslot there is a slight chance we may end up with the wrong payload mask due to overflow if the delayed_destroy_work ends up coming into play after a DP 2.1 monitor gets disconnected which causes vcpi to become 0 then we try to make the payload = ~BIT(vcpi - 1) which is a negative shift. VCPI id should never really be 0 hence skip changing the payload mask if VCPI is 0. Otherwise it leads to <7> [515.287237] xe 0000:03:00.0: [drm:drm_dp_mst_get_port_malloc [drm_display_helper]] port ffff888126ce9000 (3) <4> [515.287267] -----------[ cut here ]----------- <3> [515.287268] UBSAN: shift-out-of-bounds in ../drivers/gpu/drm/display/drm_dp_mst_topology.c:4575:36 <3> [515.287271] shift exponent -1 is negative <4> [515.287275] CPU: 7 UID: 0 PID: 3108 Comm: kworker/u64:33 Tainted: G S U 6.17.0-rc6-lgci-xe-xe-3795-3e79699fa1b216e92+ #1 PREEMPT(voluntary) <4> [515.287279] Tainted: [S]=CPU_OUT_OF_SPEC, [U]=USER <4> [515.287279] Hardware name: ASUS System Product Name/PRIME Z790-P WIFI, BIOS 1645 03/15/2024 <4> [515.287281] Workqueue: drm_dp_mst_wq drm_dp_delayed_destroy_work [drm_display_helper] <4> [515.287303] Call Trace: <4> [515.287304] <TASK> <4> [515.287306] dump_stack_lvl+0xc1/0xf0 <4> [515.287313] dump_stack+0x10/0x20 <4> [515.287316] __ubsan_handle_shift_out_of_bounds+0x133/0x2e0 <4> [515.287324] ? drm_atomic_get_private_obj_state+0x186/0x1d0 <4> [515.287333] drm_dp_atomic_release_time_slots.cold+0x17/0x3d [drm_display_helper] <4> [515.287355] mst_connector_atomic_check+0x159/0x180 [xe] <4> [515.287546] drm_atomic_helper_check_modeset+0x4d9/0xfa0 <4> [515.287550] ? __ww_mutex_lock.constprop.0+0x6f/0x1a60 <4> [515.287562] intel_atomic_check+0x119/0x2b80 [xe] <4> [515.287740] ? find_held_lock+0x31/0x90 <4> [515.287747] ? lock_release+0xce/0x2a0 <4> [515.287754] drm_atomic_check_only+0x6a2/0xb40 <4> [515.287758] ? drm_atomic_add_affected_connectors+0x12b/0x140 <4> [515.287765] drm_atomic_commit+0x6e/0xf0 <4> [515.287766] ? _pfx__drm_printfn_info+0x10/0x10 <4> [515.287774] drm_client_modeset_commit_atomic+0x25c/0x2b0 <4> [515.287794] drm_client_modeset_commit_locked+0x60/0x1b0 <4> [515.287795] ? mutex_lock_nested+0x1b/0x30 <4> [515.287801] drm_client_modeset_commit+0x26/0x50 <4> [515.287804] __drm_fb_helper_restore_fbdev_mode_unlocked+0xdc/0x110 <4> [515.287810] drm_fb_helper_hotplug_event+0x120/0x140 <4> [515.287814] drm_fbdev_client_hotplug+0x28/0xd0 <4> [515.287819] drm_client_hotplug+0x6c/0xf0 <4> [515.287824] drm_client_dev_hotplug+0x9e/0xd0 <4> [515.287829] drm_kms_helper_hotplug_event+0x1a/0x30 <4> [515.287834] drm_dp_delayed_destroy_work+0x3df/0x410 [drm_display_helper] <4> [515.287861] process_one_work+0x22b/0x6f0 <4> [515.287874] worker_thread+0x1e8/0x3d0 <4> [515.287879] ? __pfx_worker_thread+0x10/0x10 <4> [515.287882] kthread+0x11c/0x250 <4> [515.287886] ? __pfx_kthread+0x10/0x10 <4> [515.287890] ret_from_fork+0x2d7/0x310 <4> [515.287894] ? __pfx_kthread+0x10/0x10 <4> [515.287897] ret_from_fork_asm+0x1a/0x30

In the Linux kernel, the following vulnerability has been resolved: smack: /smack/doi: accept previously used values Writing to /smack/doi a value that has ever been written there in the past disables networking for non-ambient labels. E.g. # cat /smack/doi 3 # netlabelctl -p cipso list Configured CIPSO mappings (1) DOI value : 3 mapping type : PASS_THROUGH # netlabelctl -p map list Configured NetLabel domain mappings (3) domain: "_" (IPv4) protocol: UNLABELED domain: DEFAULT (IPv4) protocol: CIPSO, DOI = 3 domain: DEFAULT (IPv6) protocol: UNLABELED # cat /smack/ambient _ # cat /proc/$$/attr/smack/current _ # ping -c1 10.1.95.12 64 bytes from 10.1.95.12: icmp_seq=1 ttl=64 time=0.964 ms # echo foo >/proc/$$/attr/smack/current # ping -c1 10.1.95.12 64 bytes from 10.1.95.12: icmp_seq=1 ttl=64 time=0.956 ms unknown option 86 # echo 4 >/smack/doi # echo 3 >/smack/doi !> [ 214.050395] smk_cipso_doi:691 cipso add rc = -17 # echo 3 >/smack/doi !> [ 249.402261] smk_cipso_doi:678 remove rc = -2 !> [ 249.402261] smk_cipso_doi:691 cipso add rc = -17 # ping -c1 10.1.95.12 !!> ping: 10.1.95.12: Address family for hostname not supported # echo _ >/proc/$$/attr/smack/current # ping -c1 10.1.95.12 64 bytes from 10.1.95.12: icmp_seq=1 ttl=64 time=0.617 ms This happens because Smack keeps decommissioned DOIs, fails to re-add them, and consequently refuses to add the “default” domain map: # netlabelctl -p cipso list Configured CIPSO mappings (2) DOI value : 3 mapping type : PASS_THROUGH DOI value : 4 mapping type : PASS_THROUGH # netlabelctl -p map list Configured NetLabel domain mappings (2) domain: "_" (IPv4) protocol: UNLABELED !> (no ipv4 map for default domain here) domain: DEFAULT (IPv6) protocol: UNLABELED Fix by clearing decommissioned DOI definitions and serializing concurrent DOI updates with a new lock. Also: - allow /smack/doi to live unconfigured, since adding a map (netlbl_cfg_cipsov4_map_add) may fail. CIPSO_V4_DOI_UNKNOWN(0) indicates the unconfigured DOI - add new DOI before removing the old default map, so the old map remains if the add fails (2008-02-04, Casey Schaufler)

In the Linux kernel, the following vulnerability has been resolved: accel/amdxdna: Fix race condition when checking rpm_on When autosuspend is triggered, driver rpm_on flag is set to indicate that a suspend/resume is already in progress. However, when a userspace application submits a command during this narrow window, amdxdna_pm_resume_get() may incorrectly skip the resume operation because the rpm_on flag is still set. This results in commands being submitted while the device has not actually resumed, causing unexpected behavior. The set_dpm() is called by suspend/resume, it relied on rpm_on flag to avoid calling into rpm suspend/resume recursivly. So to fix this, remove the use of the rpm_on flag entirely. Instead, introduce aie2_pm_set_dpm() which explicitly resumes the device before invoking set_dpm(). With this change, set_dpm() is called directly inside the suspend or resume execution path. Otherwise, aie2_pm_set_dpm() is called.

In the Linux kernel, the following vulnerability has been resolved: bareudp: fix NULL pointer dereference in bareudp_fill_metadata_dst() bareudp_fill_metadata_dst() passes bareudp->sock to udp_tunnel6_dst_lookup() in the IPv6 path without a NULL check. The socket is only created in bareudp_open() and NULLed in bareudp_stop(), so calling this function while the device is down triggers a NULL dereference via sock->sk. BUG: kernel NULL pointer dereference, address: 0000000000000018 RIP: 0010:udp_tunnel6_dst_lookup (net/ipv6/ip6_udp_tunnel.c:160) Call Trace: <TASK> bareudp_fill_metadata_dst (drivers/net/bareudp.c:532) do_execute_actions (net/openvswitch/actions.c:901) ovs_execute_actions (net/openvswitch/actions.c:1589) ovs_packet_cmd_execute (net/openvswitch/datapath.c:700) genl_family_rcv_msg_doit (net/netlink/genetlink.c:1114) genl_rcv_msg (net/netlink/genetlink.c:1209) netlink_rcv_skb (net/netlink/af_netlink.c:2550) </TASK> Add a NULL check returning -ESHUTDOWN, consistent with the xmit paths in the same driver.

In the Linux kernel, the following vulnerability has been resolved: net/sched: taprio: fix NULL pointer dereference in class dump When a TAPRIO child qdisc is deleted via RTM_DELQDISC, taprio_graft() is called with new == NULL and stores NULL into q->qdiscs[cl - 1]. Subsequent RTM_GETTCLASS dump operations walk all classes via taprio_walk() and call taprio_dump_class(), which calls taprio_leaf() returning the NULL pointer, then dereferences it to read child->handle, causing a kernel NULL pointer dereference. The bug is reachable with namespace-scoped CAP_NET_ADMIN on any kernel with CONFIG_NET_SCH_TAPRIO enabled. On systems with unprivileged user namespaces enabled, an unprivileged local user can trigger a kernel panic by creating a taprio qdisc inside a new network namespace, grafting an explicit child qdisc, deleting it, and requesting a class dump. The RTM_GETTCLASS dump itself requires no capability. Oops: general protection fault, probably for non-canonical address 0xdffffc0000000007: 0000 [#1] SMP KASAN NOPTI KASAN: null-ptr-deref in range [0x0000000000000038-0x000000000000003f] RIP: 0010:taprio_dump_class (net/sched/sch_taprio.c:2478) Call Trace: <TASK> tc_fill_tclass (net/sched/sch_api.c:1966) qdisc_class_dump (net/sched/sch_api.c:2326) taprio_walk (net/sched/sch_taprio.c:2514) tc_dump_tclass_qdisc (net/sched/sch_api.c:2352) tc_dump_tclass_root (net/sched/sch_api.c:2370) tc_dump_tclass (net/sched/sch_api.c:2431) rtnl_dumpit (net/core/rtnetlink.c:6864) netlink_dump (net/netlink/af_netlink.c:2325) rtnetlink_rcv_msg (net/core/rtnetlink.c:6959) netlink_rcv_skb (net/netlink/af_netlink.c:2550) </TASK> Fix this by substituting &noop_qdisc when new is NULL in taprio_graft(), a common pattern used by other qdiscs (e.g., multiq_graft()) to ensure the q->qdiscs[] slots are never NULL. This makes control-plane dump paths safe without requiring individual NULL checks. Since the data-plane paths (taprio_enqueue and taprio_dequeue_from_txq) previously had explicit NULL guards that would drop/skip the packet cleanly, update those checks to test for &noop_qdisc instead. Without this, packets would reach taprio_enqueue_one() which increments the root qdisc's qlen and backlog before calling the child's enqueue; noop_qdisc drops the packet but those counters are never rolled back, permanently inflating the root qdisc's statistics. After this change *old can be a valid qdisc, NULL, or &noop_qdisc. Only call qdisc_put(*old) in the first case to avoid decreasing noop_qdisc's refcount, which was never increased.

In the Linux kernel, the following vulnerability has been resolved: netfilter: arp_tables: fix IEEE1394 ARP payload parsing Weiming Shi says: "arp_packet_match() unconditionally parses the ARP payload assuming two hardware addresses are present (source and target). However, IPv4-over-IEEE1394 ARP (RFC 2734) omits the target hardware address field, and arp_hdr_len() already accounts for this by returning a shorter length for ARPHRD_IEEE1394 devices. As a result, on IEEE1394 interfaces arp_packet_match() advances past a nonexistent target hardware address and reads the wrong bytes for both the target device address comparison and the target IP address. This causes arptables rules to match against garbage data, leading to incorrect filtering decisions: packets that should be accepted may be dropped and vice versa. The ARP stack in net/ipv4/arp.c (arp_create and arp_process) already handles this correctly by skipping the target hardware address for ARPHRD_IEEE1394. Apply the same pattern to arp_packet_match()." Mangle the original patch to always return 0 (no match) in case user matches on the target hardware address which is never present in IEEE1394. Note that this returns 0 (no match) for either normal and inverse match because matching in the target hardware address in ARPHRD_IEEE1394 has never been supported by arptables. This is intentional, matching on the target hardware address should never evaluate true for ARPHRD_IEEE1394. Moreover, adjust arpt_mangle to drop the packet too as AI suggests: In arpt_mangle, the logic assumes a standard ARP layout. Because IEEE1394 (FireWire) omits the target hardware address, the linear pointer arithmetic miscalculates the offset for the target IP address. This causes mangling operations to write to the wrong location, leading to packet corruption. To ensure safety, this patch drops packets (NF_DROP) when mangling is requested for these fields on IEEE1394 devices, as the current implementation cannot correctly map the FireWire ARP payload. This omits both mangling target hardware and IP address. Even if IP address mangling should be possible in IEEE1394, this would require to adjust arpt_mangle offset calculation, which has never been supported. Based on patch from Weiming Shi <bestswngs@gmail.com>.

In the Linux kernel, the following vulnerability has been resolved: slip: reject VJ receive packets on instances with no rstate array slhc_init() accepts rslots == 0 as a valid configuration, with the documented meaning of 'no receive compression'. In that case the allocation loop in slhc_init() is skipped, so comp->rstate stays NULL and comp->rslot_limit stays 0 (from the kzalloc of struct slcompress). The receive helpers do not defend against that configuration. slhc_uncompress() dereferences comp->rstate[x] when the VJ header carries an explicit connection ID, and slhc_remember() later assigns cs = &comp->rstate[...] after only comparing the packet's slot number to comp->rslot_limit. Because rslot_limit is 0, slot 0 passes the range check, and the code dereferences a NULL rstate. The configuration is reachable in-tree through PPP. PPPIOCSMAXCID stores its argument in a signed int, and (val >> 16) uses arithmetic shift. Passing 0xffff0000 therefore sign-extends to -1, so val2 + 1 is 0 and ppp_generic.c ends up calling slhc_init(0, 1). Because /dev/ppp open is gated by ns_capable(CAP_NET_ADMIN), the whole path is reachable from an unprivileged user namespace. Once the malformed VJ state is installed, any inbound VJ-compressed or VJ-uncompressed frame that selects slot 0 crashes the kernel in softirq context: Oops: general protection fault, probably for non-canonical address 0xdffffc0000000000: 0000 [#1] SMP KASAN NOPTI KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007] RIP: 0010:slhc_uncompress (drivers/net/slip/slhc.c:519) Call Trace: <TASK> ppp_receive_nonmp_frame (drivers/net/ppp/ppp_generic.c:2466) ppp_input (drivers/net/ppp/ppp_generic.c:2359) ppp_async_process (drivers/net/ppp/ppp_async.c:492) tasklet_action_common (kernel/softirq.c:926) handle_softirqs (kernel/softirq.c:623) run_ksoftirqd (kernel/softirq.c:1055) smpboot_thread_fn (kernel/smpboot.c:160) kthread (kernel/kthread.c:436) ret_from_fork (arch/x86/kernel/process.c:164) </TASK> Reject the receive side on such instances instead of touching rstate. slhc_uncompress() falls through to its existing 'bad' label, which bumps sls_i_error and enters the toss state. slhc_remember() mirrors that with an explicit sls_i_error increment followed by slhc_toss(); the sls_i_runt counter is not used here because a missing rstate is an internal configuration state, not a runt packet. The transmit path is unaffected: the only in-tree caller that picks rslots from userspace (ppp_generic.c) still supplies tslots >= 1, and slip.c always calls slhc_init(16, 16), so comp->tstate remains valid and slhc_compress() continues to work.

In the Linux kernel, the following vulnerability has been resolved: netfilter: nfnetlink_osf: fix divide-by-zero in OSF_WSS_MODULO nf_osf_match_one() computes ctx->window % f->wss.val in the OSF_WSS_MODULO branch with no guard for f->wss.val == 0. A CAP_NET_ADMIN user can add such a fingerprint via nfnetlink; a subsequent matching TCP SYN divides by zero and panics the kernel. Reject the bogus fingerprint in nfnl_osf_add_callback() above the per-option for-loop. f->wss is per-fingerprint, not per-option, so the check must run regardless of f->opt_num (including 0). Also reject wss.wc >= OSF_WSS_MAX; nf_osf_match_one() already treats that as "should not happen". Crash: Oops: divide error: 0000 [#1] SMP KASAN NOPTI RIP: 0010:nf_osf_match_one (net/netfilter/nfnetlink_osf.c:98) Call Trace: <IRQ> nf_osf_match (net/netfilter/nfnetlink_osf.c:220) xt_osf_match_packet (net/netfilter/xt_osf.c:32) ipt_do_table (net/ipv4/netfilter/ip_tables.c:348) nf_hook_slow (net/netfilter/core.c:622) ip_local_deliver (net/ipv4/ip_input.c:265) ip_rcv (include/linux/skbuff.h:1162) __netif_receive_skb_one_core (net/core/dev.c:6181) process_backlog (net/core/dev.c:6642) __napi_poll (net/core/dev.c:7710) net_rx_action (net/core/dev.c:7945) handle_softirqs (kernel/softirq.c:622)

In the Linux kernel, the following vulnerability has been resolved: openvswitch: cap upcall PID array size and pre-size vport replies The vport netlink reply helpers allocate a fixed-size skb with nlmsg_new(NLMSG_DEFAULT_SIZE, ...) but serialize the full upcall PID array via ovs_vport_get_upcall_portids(). Since ovs_vport_set_upcall_portids() accepts any non-zero multiple of sizeof(u32) with no upper bound, a CAP_NET_ADMIN user can install a PID array large enough to overflow the reply buffer, causing nla_put() to fail with -EMSGSIZE and hitting BUG_ON(err < 0). On systems with unprivileged user namespaces enabled (e.g., Ubuntu default), this is reachable via unshare -Urn since OVS vport mutation operations use GENL_UNS_ADMIN_PERM. kernel BUG at net/openvswitch/datapath.c:2414! Oops: invalid opcode: 0000 [#1] SMP KASAN NOPTI CPU: 1 UID: 0 PID: 65 Comm: poc Not tainted 7.0.0-rc7-00195-geb216e422044 #1 RIP: 0010:ovs_vport_cmd_set+0x34c/0x400 Call Trace: <TASK> genl_family_rcv_msg_doit (net/netlink/genetlink.c:1116) genl_rcv_msg (net/netlink/genetlink.c:1194) netlink_rcv_skb (net/netlink/af_netlink.c:2550) genl_rcv (net/netlink/genetlink.c:1219) netlink_unicast (net/netlink/af_netlink.c:1344) netlink_sendmsg (net/netlink/af_netlink.c:1894) __sys_sendto (net/socket.c:2206) __x64_sys_sendto (net/socket.c:2209) do_syscall_64 (arch/x86/entry/syscall_64.c:63) entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:130) </TASK> Kernel panic - not syncing: Fatal exception Reject attempts to set more PIDs than nr_cpu_ids in ovs_vport_set_upcall_portids(), and pre-compute the worst-case reply size in ovs_vport_cmd_msg_size() based on that bound, similar to the existing ovs_dp_cmd_msg_size(). nr_cpu_ids matches the cap already used by the per-CPU dispatch configuration on the datapath side (ovs_dp_cmd_fill_info() serialises at most nr_cpu_ids PIDs), so the two sides stay consistent.

In the Linux kernel, the following vulnerability has been resolved: bpf: fix end-of-list detection in cgroup_storage_get_next_key() list_next_entry() never returns NULL -- when the current element is the last entry it wraps to the list head via container_of(). The subsequent NULL check is therefore dead code and get_next_key() never returns -ENOENT for the last element, instead reading storage->key from a bogus pointer that aliases internal map fields and copying the result to userspace. Replace it with list_entry_is_head() so the function correctly returns -ENOENT when there are no more entries.

In the Linux kernel, the following vulnerability has been resolved: Bluetooth: L2CAP: Fix null-ptr-deref in l2cap_sock_get_sndtimeo_cb() Add the same NULL guard already present in l2cap_sock_resume_cb() and l2cap_sock_ready_cb().

In the Linux kernel, the following vulnerability has been resolved: Bluetooth: L2CAP: Fix null-ptr-deref in l2cap_sock_new_connection_cb() Add the same NULL guard already present in l2cap_sock_resume_cb() and l2cap_sock_ready_cb().

In the Linux kernel, the following vulnerability has been resolved: Bluetooth: L2CAP: Fix null-ptr-deref in l2cap_sock_state_change_cb() Add the same NULL guard already present in l2cap_sock_resume_cb() and l2cap_sock_ready_cb().