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In the Linux kernel, the following vulnerability has been resolved: net: bcmgenet: fix NULL dereference in set_coalesce before first open The Rx ring priv and index are only set in bcmgenet_init_rx_ring(), which runs at open. Setting the Rx coalescing parameters on an interface that was never opened, e.g. "ethtool -C eth0 rx-usecs 50", dereferences a NULL ring->priv. The oops happens with RTNL held, so networking stays stuck until a reboot: Unable to handle kernel paging request at virtual address 0000000000002788 pc : bcmgenet_set_rx_coalesce.isra.0+0x10/0x88 lr : bcmgenet_set_coalesce+0xe8/0x180 Call trace: bcmgenet_set_rx_coalesce.isra.0+0x10/0x88 (P) __ethnl_set_coalesce.isra.0+0x490/0x570 ethnl_set_coalesce+0x48/0xc0 ethnl_default_set_doit+0xf4/0x230 genl_family_rcv_msg_doit+0xe8/0x160 genl_rcv_msg+0x220/0x2a0 netlink_rcv_skb+0x68/0x140 genl_rcv+0x40/0x60 netlink_unicast+0x338/0x3c0 netlink_sendmsg+0x19c/0x3f8 __sock_sendmsg+0x64/0xc0 __sys_sendto+0x124/0x198 __arm64_sys_sendto+0x30/0x48 Set priv and index at probe. Writing the registers while the interface is down is harmless because open resets the MAC and bcmgenet_init_rx_coalesce() reapplies the stored values. It was observed on a Raspberry Pi CM4, but should apply to all other genet devices.

In the Linux kernel, the following vulnerability has been resolved: net: cap skb->queue_mapping when the tx queue is picked skbedit can set skb->queue_mapping and raise the per-CPU skip_txqueue flag so __dev_queue_xmit() honours the mapping. __dev_queue_xmit() cleared the flag before sch_handle_egress() and only read it afterwards, so the flag was not confined to the xmit that set it: a nested xmit (mirred redirect or mirror, or a drop after skbedit) could set the flag and the outer xmit would consume it for an skb that never went through skbedit. A forwarded packet still carries the ingress NIC's rx_queue + 1 in skb->queue_mapping, so the outer device then indexes its tx queue state with that stale value. Taprio's child array q->qdiscs[] is sized to the device's queue count, so taprio_enqueue() indexes past its allocation and dereferences the result as a struct Qdisc *. We (ab)use the skb->nf_skip_egress which means "skip netfilter egress for this packet" to tag to "am I in tc egress?". Despite the overload I dont see it as a conflict since the marker is set only around the single sch_handle_egress() call and ingress path is guarded by tc_at_ingress. I will send a followup(net-next) patch once this hits net-next to rename the skb->nf_skip_egress bit/flag to skb->skip_egress Arm the flag only from the egress classifier that can use it: raise skip_txqueue from tcf_skbedit_act() only when it runs inside sch_handle_egress(), thanks to skb->nf_skip_egress. An egress qdisc classifier runs in q->enqueue(), after the tx queue has been picked, so a mapping it sets cannot affect the current packet; arming the flag there only pollutes it for a later xmit. Then own the flag for the xmit frame the egress hook runs in: save the incoming value and clear it just before sch_handle_egress(), and restore it after the hook - on the consumed (drop) path, or, in the same call that reads it, on the surviving path. The save and the restores stay inside the egress_needed_key static branch, so a packet pays for them only when egress hooks are active (2f1e85b1aee4). Store the value netdev_cap_txqueue() selected back into skb->queue_mapping in netdev_tx_queue_mapping(), as netdev_core_pick_tx() already does, so the skip_txqueue path never hands a later reader on the xmit path a mapping the device cannot serve. A store made still later in the same frame, by a tc BPF program attached to a transmit qdisc, is outside this path and is not re-capped; a separate followup will resolve that path. netdev_xmit_skip_txqueue() returns the previous flag value so the save-and-clear is one call, and a no-op stub is provided when CONFIG_NET_EGRESS is disabled. skb->nf_skip_egress is compiled under CONFIG_NET_EGRESS rather than CONFIG_NETFILTER_SKIP_EGRESS, so skb_at_tc_egress() is valid whenever the egress path is built. A local user in a network namespace can redirect a packet from a device with more TX queues to one with fewer after setting a mapping valid only on the larger device. That reaches these reads and, under KASAN, faults with "slab-out-of-bounds in taprio_enqueue". Conditions to recreate the bug: the report's own trigger is a local user with CAP_NET_ADMIN in a network namespace, so no eBPF program is needed. With CONFIG_NET_SCH_TAPRIO=y, CONFIG_NET_ACT_SKBEDIT=y, CONFIG_NET_ACT_MIRRED=y, CONFIG_NET_CLS_MATCHALL=y, CONFIG_NET_SCH_PRIO=y and KASAN enabled, create qa (3 queues), qb (2 queues) and qc (1 queue) as dummy devices; put a taprio root on qb (num_tc 1, queues 2@0) and clsact on all three; then add an egress matchall filter on every device. On qa: "action skbedit queue_mapping 2 pipe action mirred egress redirect dev qb". On qb: "action mirred egress mirror dev qc". On qc: "action skbedit queue_mapping 0 pipe". Send one packet out qa. qc's skbedit sets the flag while qb's outer xmit is in flight; without the fix qb consumes it and reads its two-entry taprio child array with the forwarded packet's stale mapping. A qc whose skb ---truncated---

In the Linux kernel, the following vulnerability has been resolved: net: ethernet: mtk_eth_soc: allocate dummy netdev sooner The RX rings and the shared NAPI are carried by an internal "dummy" netdev (eth->dummy_dev). mtk_probe() creates that dummy device, and adds the shared tx/rx NAPI to it, only after the MAC netdevs have been registered. That order has been there since the MT7623 support was added and leaves a window in which the netdevs are visible to the network core before the shared NAPI and the dummy device exist. If anything brings the first netdev up during that window (e.g. netifd opening the WAN link the instant the interface is registered), the first-open path runs without them. On NETSYS v2 and later SoCs mtk_rx_alloc() -> __xdp_rxq_info_reg() then dereferences eth->dummy_dev == NULL: WARNING: CPU: ... Missing net_device from driver in net/core/xdp.c and mtk_open() fails with -ENODEV. On NETSYS v1 SoCs (MT7621/MT7622/MT7623/MT7629) there is no page pool, so the same open instead calls napi_enable() on a napi_struct that netif_napi_add() has not initialised yet and dereferences a NULL napi->dev. Allocate the dummy netdev and add the shared tx/rx NAPI to it before the register_netdev() loop. Both the dummy-allocation failure and a register_netdev() failure now unwind through mtk_unreg_dev(), which unregisters the net_device notifiers and the netdevs registered so far, stopping a concurrently-opened netdev (ndo_stop) and its NAPI before the dummy carrier is freed. A netdev that opened during the window can also have queued the frame-engine reset worker (via the tx watchdog or phylink), so the probe error path now cancels eth->pending_work before freeing the shared state, as mtk_cleanup() already does on remove.

In the Linux kernel, the following vulnerability has been resolved: net: sparx5: skip ptp deinit if init was skipped sparx5_ptp_init() returns early on the base lan969x variants because they do not have the SPX5_FEATURE_PTP flag. It also returns early when no "ptp" interrupt is described. Unbinding the driver then causes a NULL pointer dereference when cleaning up uninitialized tx_skbs queues: Unable to handle kernel NULL pointer dereference at virtual address 0000000000000008 Call trace: skb_queue_purge_reason+0x68/0x120 (P) sparx5_ptp_deinit+0x64/0xc0 mchp_sparx5_remove+0x38/0x70 platform_remove+0x20/0x30 device_remove+0x4c/0x80 Before per-port tx_skbs were added, a NULL dereference would have happened when calling ptp_clock_unregister() on the never-registered PTP clocks. Fix by returning early in sparx5_ptp_deinit() if PTP is not used.

In the Linux kernel, the following vulnerability has been resolved: ipvs: filter some flags received in the backup server While the IPVS SYNC protocol is not secure by design we can still protect the backup server from messages that can wreak havoc. This commit addresses problems from received connection flags or their combinations. We now drop messages as follows: 1. the NO_CPORT+TEMPLATE combination allows lookups for normal connections to hit template which can break in many ways. While the master does not sync connections with NO_CPORT flag, i.e. before they are established, we still accept NO_CPORT without TEMPLATE. 2. ONE_PACKET: it is not sent by master, so we do not expect it in backup. Before now it was ignored by IP_VS_CONN_F_BACKUP_MASK for protocol v1 while protocol v0 created connections that are not hashed and dropped immediately. Better to apply the IP_VS_CONN_F_BACKUP_MASK also to the flags from v0 messages for consistency with v1.

In the Linux kernel, the following vulnerability has been resolved: netfilter: bpf: reject invalid NAT manipulation types As bpf_ct_set_nat_info() is not validating the NAT manipulation type a wrong value can be passed directly to nf_nat_setup_info(). This triggers the WARN_ON() at nf_nat_setup_info() and if panic_on_warn isn't set, then IPS_SRC_NAT_DONE is set without adding nat_bysource and conntrack cleanup tries to unlink an uninitialized hlist node. Fix this by checking that NAT manipulation type is correct before calling nf_nat_setup_info(). In addition, if the WARN_ON is hit, return NF_DROP instead of continuing with the processing to avoid similar situations in the future.

In the Linux kernel, the following vulnerability has been resolved: netfilter: flowtable: generalize pending status bit Rename NF_FLOW_HW_PENDING to NF_FLOW_PENDING and use it to inhibit the flowtable GC worker until pending hw offload work has been completed. Apparently, nf_flow_offload_stats() can schedule work to retrieve stats while the flow is being removed by GC. And this bit can also be used in a follow up patch to disable GC until the flow has been fully added in both directions. Revert the reordering done in commit d644b23afe1e ("netfilter: flowtable: publish HW_DEAD after worker is done") to prevent a race between GC and hw offload handler.

In the Linux kernel, the following vulnerability has been resolved: net/mlx5e: Fix AF_XDP TX timestamp teardown NULL dereference During XSK TX queue teardown, outstanding descriptors are completed without a CQE. If one requested a TX timestamp, the completion path passes that NULL CQE to mlx5e_xsk_fill_timestamp(), which dereferences it. Return zero when no CQE is available, indicating that teardown did not produce a TX timestamp.

In the Linux kernel, the following vulnerability has been resolved: perf: Fix race between perf_event_exit_task() and perf_pending_task() A race condition exists between perf_event_exit_task() and perf_pending_task() during begin_new_exec(). During begin_new_exec(), perf_event_exit_task() may be called, and the PF_EXITING flag is not set on task. So perf_sigtrap() continues to execute and triggers WARN_ON_ONCE(event->ctx->task != current). Since both task exit and exec paths can call perf_event_exit_task() which sets ctx->task to TASK_TOMBSTONE, fix this by explicitly checking if event->ctx->task equals TASK_TOMBSTONE and dropping the redundant PF_EXITING check.

In the Linux kernel, the following vulnerability has been resolved: bpf: Fix objects stuck in free_by_rcu_ttrace do_call_rcu_ttrace() returns early when call_rcu_ttrace_in_progress is set and leaves the objects in free_by_rcu_ttrace. __free_rcu() frees waiting_for_gp_ttrace only and clears the flag. Hence the objects that free_bulk() or __free_by_rcu() added while RCU tasks trace GP was in flight stay in free_by_rcu_ttrace until free_bulk() or alloc_bulk() is called for the same bpf_mem_cache again, which may never happen. The number of such objects is not bounded. Turn call_rcu_ttrace_in_progress into three states: 0 - idle 1 - __free_rcu() is queued 2 - __free_rcu() is queued and free_by_rcu_ttrace got more objects since do_call_rcu_ttrace() sets 2. __free_rcu() does cmpxchg(1 -> 0) and starts the next GP when it fails. It cannot clear the flag first and check free_by_rcu_ttrace later, since bpf_mem_alloc_destroy() frees bpf_mem_cache without waiting for RCU callbacks when the flag is zero. Now __free_rcu() queues itself, so the one that didn't see 'draining' may do call_rcu_tasks_trace() after rcu_barrier_tasks_trace() in free_mem_alloc(). Queue it under rcu_read_lock() and do synchronize_rcu() before the barriers. Calling rcu_barrier_tasks_trace() twice works too, but creating and destroying hash maps in a loop on many cpus slows down to one free_mem_alloc() per GP and kworkers pile up.

In the Linux kernel, the following vulnerability has been resolved: futex: Fix private hash use-after-free on resize poll_state_synchronize_rcu(mm->futex.phash.batches) is used by futex_ref_drop() to check that a grace period has passed since the current hash was published. This relies on batches referencing a grace period which started after the hash pointer was assigned. __futex_pivot_hash() sets mmph->batches before it replaces mmph->hash: scoped_guard(rcu) { mmph->batches = get_state_synchronize_rcu(); rcu_assign_pointer(mmph->hash, new); } The scoped_guard(rcu) doesn't stop new grace periods from starting, and if one starts between those two assignments, futex_ref_drop() can move forward while a reader still holds a pointer to the old hash. Fix things by setting mmph->batches after assigning mmph->hash. The scoped_guard(rcu) isn't needed, so let's drop that as well.

In the Linux kernel, the following vulnerability has been resolved: bpf: Fix missing migration protection in __rhtab_map_lookup_and_delete_batch() bpf_mem_cache_free_rcu() uses this_cpu_ptr() which requires migration to be disabled. All callers of rhtab_delete_elem() disable migration except __rhtab_map_lookup_and_delete_batch(), which calls it under rcu_read_lock() only. On CONFIG_PREEMPT_RCU, rcu_read_lock() does not disable preemption or migration, so the task can migrate between CPUs during the delete loop, causing this_cpu_ptr() to trigger: BUG: using smp_processor_id() in preemptible [00000000] code Fix by wrapping the delete loop in migrate_disable()/migrate_enable() in __rhtab_map_lookup_and_delete_batch(), matching the migration protection that the other callers already provide.

In the Linux kernel, the following vulnerability has been resolved: drm/amd/display: guard dc_sink dereferences in MST mode validation dm_dp_mst_is_port_support_mode() reads aconnector->dc_sink->dsc_caps... for the DSC branch-throughput check, and get_conv_frl_bw()'s HDMI-PCON FRL-bandwidth path reads aconnector->dc_sink->edid_caps.max_frl_rate, both without a NULL check. dc_sink is cleared asynchronously on MST unplug, and both functions run from paths that the driver's own comments document as racing that teardown: the connector probe worker's ->mode_valid callback and a compositor's atomic check, neither of which holds the MST manager lock that the teardown path uses. The former does have an existing dsc_aux NULL check, but dsc_aux isn't reliably cleared in every path that clears dc_sink, so it doesn't cover this. Fail the port-support check and skip the FRL conversion path when the sink is already gone. (cherry picked from commit 7c3db8da4e039698ae198c870712428644e965c7)

In the Linux kernel, the following vulnerability has been resolved: drm/amd/display: check dc_state_create_copy() for NULL in dm_suspend dc_state_create_copy() can return NULL on allocation failure. dm_suspend() only conditionally skips dm_gpureset_toggle_interrupts() and continues execution, returning success. dm_resume() then dereferences the NULL cached_dc_state in link_enc_cfg_copy() and the following dc_state->stream_count loop, crashing during GPU reset recovery. Return -ENOMEM immediately if the copy fails, so the caller aborts suspend instead of leaving a NULL cached state for resume. (cherry picked from commit 84b6d7932fdd2857795a257f9f258562a3cddcab)

In the Linux kernel, the following vulnerability has been resolved: drm/amdgpu/gfx6: fix firmware leak on teardown The firmware requested in gfx_v6_0_init_microcode() is not released when the GFX block is torn down, leaking the firmware resources. Add gfx_v6_0_free_microcode() and call it from gfx_v6_0_sw_fini() to release the PFP, ME, CE and RLC firmware. (cherry picked from commit 386e81346f95ab0be5a82c5535de932e7a456924)

In the Linux kernel, the following vulnerability has been resolved: drm/mediatek: Add missing IS_ERR check for ovl_adaptor platform device platform_device_register_data() can fail and return an ERR_PTR, but the return value is used without checking, leading to an invalid pointer being stored in ddp_comp[].dev and passed to component_match_add() and mtk_ddp_comp_init(), which could result in a kernel crash. Add an IS_ERR() check to jump to the error handling path on failure.

In the Linux kernel, the following vulnerability has been resolved: drm/mediatek: Fix ovl adaptor platform device leak mtk_drm_probe() creates an OVL adaptor platform device with platform_device_register_data() when the display pipeline requires the OVL adaptor. If a later initialization step fails, the probe error path releases the DRM resources without unregistering the already registered OVL adaptor device. The normal remove path likewise leaves the device registered after the DRM driver is unbound. Keep track of whether the OVL adaptor was successfully registered and unregister it on probe failure. Also recover the platform device from the stored DDP component device and unregister it during normal removal. The issue was identified by a static analysis tool I developed and confirmed by manual review.

In the Linux kernel, the following vulnerability has been resolved: drm/mediatek: Fix pdev reference leak in mtk_drm_bind() When the device is not the mmsys master, mtk_drm_bind() returns early after taking a reference on the disp-mutex device via of_find_device_by_node(), without ever dropping it: mtk_drm_unbind() only puts mutex_dev for the master. Drop the reference before returning from the non-master path.

In the Linux kernel, the following vulnerability has been resolved: drm/amdgpu: fix IP instance memory leak on kobject add failure amdgpu_discovery_sysfs_ips() allocates ip_hw_instance with kzalloc_flex() and initializes its embedded kobject before calling kobject_add(). If kobject_add() fails, the return value is ignored and execution continues without dropping the initial kobject reference. The failed kobject is not retained in the kset list, so the normal sysfs teardown path cannot find it. As a result, ip_hw_instance_release() is never called and the ip_hw_instance allocation is leaked. Call kobject_put() when kobject_add() fails so the initial reference is dropped and ip_hw_instance_release() can free the allocation. Keep the existing best-effort sysfs behavior by continuing with the remaining IP entries after the failed registration. The issue was identified by a static analysis tool I developed and confirmed by manual review. (cherry picked from commit 5c75fbcca8af1096d8d9415b91d8ea6212c22ee1)

In the Linux kernel, the following vulnerability has been resolved: drm/amdgpu: fix ACP MFD device leak on init failure acp_hw_init() registers ACP child devices with mfd_add_devices() before attaching them to the ACP power domain and initializing the hardware. If attaching a child to the power domain fails, or if the ACP reset or clock enable operation times out, the failure path frees only the source cell, resource, and platform-data allocations. The child platform devices already registered by mfd_add_devices() remain registered and are never released. Remove the children from the power domain and unregister the MFD devices on failures that occur after mfd_add_devices() succeeds. Keep mfd_add_devices() failures on the existing cleanup path since the MFD core already rolls back partially registered children itself. The issue was identified by a static analysis tool I developed and confirmed by manual review. (cherry picked from commit 63da68d6a2279ec945581c990c5a59a5ae8b5560)

In the Linux kernel, the following vulnerability has been resolved: binder: fix is_failure flag for superseded transaction cleanup When a TF_UPDATE_TXN transaction supersedes a pending async transaction, binder_release_entire_buffer() is called with is_failure=false. Since the superseded transaction was never delivered, binder_apply_fd_fixups() was never called and no fds were installed in the target process. With is_failure=false, the BINDER_TYPE_FDA cleanup handler interprets stale buffer contents as installed fd numbers and passes them to binder_deferred_fd_close(), closing unrelated file descriptors. Pass is_failure=true since the transaction was never delivered to the target, matching the semantics of all other undelivered-transaction cleanup paths.

In the Linux kernel, the following vulnerability has been resolved: binder: fix leaked fd fixups on TF_UPDATE_TXN supersede When a TF_UPDATE_TXN transaction supersedes a pending async transaction in a frozen process, the outdated transaction is freed with kfree() directly. This skips binder_free_txn_fixups(), leaking all binder_txn_fd_fixup entries and their fget()'d struct file references. The leaked file refcounts never reach zero, so the struct file objects are permanently pinned in memory. They survive process exit and accumulate across invocations until file-max exhaustion. Every other transaction cleanup path (binder_free_transaction(), binder_transaction() error paths, binder_release_work()) correctly calls binder_free_txn_fixups(). Add the missing call before kfree() in the t_outdated cleanup block.

In the Linux kernel, the following vulnerability has been resolved: binderfs: fix UAF write in binder_add_device binderfs_binder_device_create() publishes the new dentry with d_make_persistent() and then calls simple_done_creating(), which drops the parent directory lock and the creator's dentry reference. It then calls binder_add_device() to register the device in the global binder_devices list. After simple_done_creating() releases the parent directory lock, a concurrent unlinkat() can remove the new device entry. Dropping the creator's dentry reference can then trigger binderfs_evict_inode(), freeing the device. binder_add_device() later accesses the freed object, causing UAF write. Found by a modified Syzkaller: BUG: KASAN: slab-use-after-free in hlist_add_head include/linux/list.h:1073 [inline] BUG: KASAN: slab-use-after-free in binder_add_device+0xa9/0xc0 drivers/android/binder.c:7068 Write of size 8 at addr ffff88805b340c00 by task syz.1.532/11389 CPU: 0 UID: 0 PID: 11389 Comm: syz.1.532 Not tainted 7.2.0 #4 PREEMPT(full) 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: <TASK> __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x10e/0x1f0 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:378 [inline] print_report+0xf7/0x600 mm/kasan/report.c:482 kasan_report+0xe4/0x120 mm/kasan/report.c:595 hlist_add_head include/linux/list.h:1073 [inline] binder_add_device+0xa9/0xc0 drivers/android/binder.c:7068 binderfs_binder_device_create.isra.0+0x724/0x990 drivers/android/binderfs.c:196 binder_ctl_ioctl+0x186/0x1b0 drivers/android/binderfs.c:241 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:597 [inline] __se_sys_ioctl fs/ioctl.c:583 [inline] __x64_sys_ioctl+0x18e/0x210 fs/ioctl.c:583 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x116/0x800 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7ff9027a833d Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 90 f3 0f 1e fa 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b0 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007ff903674018 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007ff902a35fa0 RCX: 00007ff9027a833d RDX: 0000200000000500 RSI: 00000000c1086201 RDI: 0000000000000004 RBP: 00007ff902850733 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ff902a36038 R14: 00007ff902a35fa0 R15: 00007ffd7166bfa0 </TASK> Allocated by task 11389: kasan_save_stack+0x33/0x60 mm/kasan/common.c:57 kasan_save_track+0x14/0x30 mm/kasan/common.c:78 poison_kmalloc_redzone mm/kasan/common.c:398 [inline] __kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:415 kasan_kmalloc include/linux/kasan.h:263 [inline] __kmalloc_cache_noprof+0x2e4/0x6f0 mm/slub.c:5489 _kmalloc_noprof include/linux/slab.h:988 [inline] _kzalloc_noprof include/linux/slab.h:1309 [inline] binderfs_binder_device_create.isra.0+0x17a/0x990 drivers/android/binderfs.c:148 binder_ctl_ioctl+0x186/0x1b0 drivers/android/binderfs.c:241 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:597 [inline] __se_sys_ioctl fs/ioctl.c:583 [inline] __x64_sys_ioctl+0x18e/0x210 fs/ioctl.c:583 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x116/0x800 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f Freed by task 11389: kasan_save_stack+0x33/0x60 mm/kasan/common.c:57 kasan_save_track+0x14/0x30 mm/kasan/common.c:78 kasan_save_free_info+0x3b/0x60 mm/kasan/generic.c:584 poison_slab_object mm/kasan/common.c:253 [inline] __kasan_slab_free+0x5f/0x80 mm/kasan/common.c:285 kasan_slab_free include/linux/kasan.h:235 [inline] slab_free_hook mm/slub.c:2677 [inline] slab_free mm/slub.c:6377 [inline] kfree+0x2fc/0x6e0 mm/slub.c:6692 binderf ---truncated---

In the Linux kernel, the following vulnerability has been resolved: nitro_enclaves: fix use-after-free on SLOT_ALLOC failure When ne_create_vm_ioctl() fails the SLOT_ALLOC request after anon_inode_getfile() has succeeded, the error path calls fput(enclave_file) and then frees ne_enclave. In normal userspace context, fput() defers the final __fput() via task_work. ne_enclave_release() therefore runs after ne_enclave has already been freed and dereferences ne_enclave->slot_uid, causing a use-after-free: KASAN: slab-use-after-free in ne_enclave_release. The enclave has no slot allocated and is not yet linked into the enclaves list on this error path, so ne_enclave_release() is expected to return early when slot_uid is zero. However, reading slot_uid already accesses the freed object. Clear enclave_file->private_data before fput() on the error path. ne_enclave_release() then returns immediately when private_data is NULL, leaving the ioctl error path as the sole owner of ne_enclave. This is safe because the file has not been fd_install()'d yet. Tested on an AWS EC2 m5.2xlarge with CONFIG_KASAN=y. Without the patch, the reproducer triggers a KASAN slab-use-after-free on every SLOT_ALLOC failure. With the patch, no KASAN report is produced and the SLOT_ALLOC error is still returned. Normal enclave creation and teardown are unaffected.