Search Results (20133 CVEs found)

CVE Vendors Products Updated CVSS v3.1
CVE-2022-50659 1 Linux 1 Linux Kernel 2026-04-15 5.5 Medium
In the Linux kernel, the following vulnerability has been resolved: hwrng: geode - Fix PCI device refcount leak for_each_pci_dev() is implemented by pci_get_device(). The comment of pci_get_device() says that it will increase the reference count for the returned pci_dev and also decrease the reference count for the input pci_dev @from if it is not NULL. If we break for_each_pci_dev() loop with pdev not NULL, we need to call pci_dev_put() to decrease the reference count. We add a new struct 'amd_geode_priv' to record pointer of the pci_dev and membase, and then add missing pci_dev_put() for the normal and error path.
CVE-2022-50656 1 Linux 1 Linux Kernel 2026-04-15 5.5 Medium
In the Linux kernel, the following vulnerability has been resolved: nfc: pn533: Clear nfc_target before being used Fix a slab-out-of-bounds read that occurs in nla_put() called from nfc_genl_send_target() when target->sensb_res_len, which is duplicated from an nfc_target in pn533, is too large as the nfc_target is not properly initialized and retains garbage values. Clear nfc_targets with memset() before they are used. Found by a modified version of syzkaller. BUG: KASAN: slab-out-of-bounds in nla_put Call Trace: memcpy nla_put nfc_genl_dump_targets genl_lock_dumpit netlink_dump __netlink_dump_start genl_family_rcv_msg_dumpit genl_rcv_msg netlink_rcv_skb genl_rcv netlink_unicast netlink_sendmsg sock_sendmsg ____sys_sendmsg ___sys_sendmsg __sys_sendmsg do_syscall_64
CVE-2022-50654 1 Linux 1 Linux Kernel 2026-04-15 5.5 Medium
In the Linux kernel, the following vulnerability has been resolved: bpf: Fix panic due to wrong pageattr of im->image In the scenario where livepatch and kretfunc coexist, the pageattr of im->image is rox after arch_prepare_bpf_trampoline in bpf_trampoline_update, and then modify_fentry or register_fentry returns -EAGAIN from bpf_tramp_ftrace_ops_func, the BPF_TRAMP_F_ORIG_STACK flag will be configured, and arch_prepare_bpf_trampoline will be re-executed. At this time, because the pageattr of im->image is rox, arch_prepare_bpf_trampoline will read and write im->image, which causes a fault. as follows: insmod livepatch-sample.ko # samples/livepatch/livepatch-sample.c bpftrace -e 'kretfunc:cmdline_proc_show {}' BUG: unable to handle page fault for address: ffffffffa0206000 PGD 322d067 P4D 322d067 PUD 322e063 PMD 1297e067 PTE d428061 Oops: 0003 [#1] PREEMPT SMP PTI CPU: 2 PID: 270 Comm: bpftrace Tainted: G E K 6.1.0 #5 RIP: 0010:arch_prepare_bpf_trampoline+0xed/0x8c0 RSP: 0018:ffffc90001083ad8 EFLAGS: 00010202 RAX: ffffffffa0206000 RBX: 0000000000000020 RCX: 0000000000000000 RDX: ffffffffa0206001 RSI: ffffffffa0206000 RDI: 0000000000000030 RBP: ffffc90001083b70 R08: 0000000000000066 R09: ffff88800f51b400 R10: 000000002e72c6e5 R11: 00000000d0a15080 R12: ffff8880110a68c8 R13: 0000000000000000 R14: ffff88800f51b400 R15: ffffffff814fec10 FS: 00007f87bc0dc780(0000) GS:ffff88803e600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffffffffa0206000 CR3: 0000000010b70000 CR4: 00000000000006e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: <TASK> bpf_trampoline_update+0x25a/0x6b0 __bpf_trampoline_link_prog+0x101/0x240 bpf_trampoline_link_prog+0x2d/0x50 bpf_tracing_prog_attach+0x24c/0x530 bpf_raw_tp_link_attach+0x73/0x1d0 __sys_bpf+0x100e/0x2570 __x64_sys_bpf+0x1c/0x30 do_syscall_64+0x5b/0x80 entry_SYSCALL_64_after_hwframe+0x63/0xcd With this patch, when modify_fentry or register_fentry returns -EAGAIN from bpf_tramp_ftrace_ops_func, the pageattr of im->image will be reset to nx+rw.
CVE-2022-50648 1 Linux 1 Linux Kernel 2026-04-15 5.5 Medium
In the Linux kernel, the following vulnerability has been resolved: ftrace: Fix recursive locking direct_mutex in ftrace_modify_direct_caller Naveen reported recursive locking of direct_mutex with sample ftrace-direct-modify.ko: [ 74.762406] WARNING: possible recursive locking detected [ 74.762887] 6.0.0-rc6+ #33 Not tainted [ 74.763216] -------------------------------------------- [ 74.763672] event-sample-fn/1084 is trying to acquire lock: [ 74.764152] ffffffff86c9d6b0 (direct_mutex){+.+.}-{3:3}, at: \ register_ftrace_function+0x1f/0x180 [ 74.764922] [ 74.764922] but task is already holding lock: [ 74.765421] ffffffff86c9d6b0 (direct_mutex){+.+.}-{3:3}, at: \ modify_ftrace_direct+0x34/0x1f0 [ 74.766142] [ 74.766142] other info that might help us debug this: [ 74.766701] Possible unsafe locking scenario: [ 74.766701] [ 74.767216] CPU0 [ 74.767437] ---- [ 74.767656] lock(direct_mutex); [ 74.767952] lock(direct_mutex); [ 74.768245] [ 74.768245] *** DEADLOCK *** [ 74.768245] [ 74.768750] May be due to missing lock nesting notation [ 74.768750] [ 74.769332] 1 lock held by event-sample-fn/1084: [ 74.769731] #0: ffffffff86c9d6b0 (direct_mutex){+.+.}-{3:3}, at: \ modify_ftrace_direct+0x34/0x1f0 [ 74.770496] [ 74.770496] stack backtrace: [ 74.770884] CPU: 4 PID: 1084 Comm: event-sample-fn Not tainted ... [ 74.771498] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), ... [ 74.772474] Call Trace: [ 74.772696] <TASK> [ 74.772896] dump_stack_lvl+0x44/0x5b [ 74.773223] __lock_acquire.cold.74+0xac/0x2b7 [ 74.773616] lock_acquire+0xd2/0x310 [ 74.773936] ? register_ftrace_function+0x1f/0x180 [ 74.774357] ? lock_is_held_type+0xd8/0x130 [ 74.774744] ? my_tramp2+0x11/0x11 [ftrace_direct_modify] [ 74.775213] __mutex_lock+0x99/0x1010 [ 74.775536] ? register_ftrace_function+0x1f/0x180 [ 74.775954] ? slab_free_freelist_hook.isra.43+0x115/0x160 [ 74.776424] ? ftrace_set_hash+0x195/0x220 [ 74.776779] ? register_ftrace_function+0x1f/0x180 [ 74.777194] ? kfree+0x3e1/0x440 [ 74.777482] ? my_tramp2+0x11/0x11 [ftrace_direct_modify] [ 74.777941] ? __schedule+0xb40/0xb40 [ 74.778258] ? register_ftrace_function+0x1f/0x180 [ 74.778672] ? my_tramp1+0xf/0xf [ftrace_direct_modify] [ 74.779128] register_ftrace_function+0x1f/0x180 [ 74.779527] ? ftrace_set_filter_ip+0x33/0x70 [ 74.779910] ? __schedule+0xb40/0xb40 [ 74.780231] ? my_tramp1+0xf/0xf [ftrace_direct_modify] [ 74.780678] ? my_tramp2+0x11/0x11 [ftrace_direct_modify] [ 74.781147] ftrace_modify_direct_caller+0x5b/0x90 [ 74.781563] ? 0xffffffffa0201000 [ 74.781859] ? my_tramp1+0xf/0xf [ftrace_direct_modify] [ 74.782309] modify_ftrace_direct+0x1b2/0x1f0 [ 74.782690] ? __schedule+0xb40/0xb40 [ 74.783014] ? simple_thread+0x2a/0xb0 [ftrace_direct_modify] [ 74.783508] ? __schedule+0xb40/0xb40 [ 74.783832] ? my_tramp2+0x11/0x11 [ftrace_direct_modify] [ 74.784294] simple_thread+0x76/0xb0 [ftrace_direct_modify] [ 74.784766] kthread+0xf5/0x120 [ 74.785052] ? kthread_complete_and_exit+0x20/0x20 [ 74.785464] ret_from_fork+0x22/0x30 [ 74.785781] </TASK> Fix this by using register_ftrace_function_nolock in ftrace_modify_direct_caller.
CVE-2025-40308 1 Linux 1 Linux Kernel 2026-04-15 7.0 High
In the Linux kernel, the following vulnerability has been resolved: Bluetooth: bcsp: receive data only if registered Currently, bcsp_recv() can be called even when the BCSP protocol has not been registered. This leads to a NULL pointer dereference, as shown in the following stack trace: KASAN: null-ptr-deref in range [0x0000000000000108-0x000000000000010f] RIP: 0010:bcsp_recv+0x13d/0x1740 drivers/bluetooth/hci_bcsp.c:590 Call Trace: <TASK> hci_uart_tty_receive+0x194/0x220 drivers/bluetooth/hci_ldisc.c:627 tiocsti+0x23c/0x2c0 drivers/tty/tty_io.c:2290 tty_ioctl+0x626/0xde0 drivers/tty/tty_io.c:2706 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:907 [inline] __se_sys_ioctl+0xfc/0x170 fs/ioctl.c:893 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f To prevent this, ensure that the HCI_UART_REGISTERED flag is set before processing received data. If the protocol is not registered, return -EUNATCH.
CVE-2025-40307 1 Linux 1 Linux Kernel 2026-04-15 7.0 High
In the Linux kernel, the following vulnerability has been resolved: exfat: validate cluster allocation bits of the allocation bitmap syzbot created an exfat image with cluster bits not set for the allocation bitmap. exfat-fs reads and uses the allocation bitmap without checking this. The problem is that if the start cluster of the allocation bitmap is 6, cluster 6 can be allocated when creating a directory with mkdir. exfat zeros out this cluster in exfat_mkdir, which can delete existing entries. This can reallocate the allocated entries. In addition, the allocation bitmap is also zeroed out, so cluster 6 can be reallocated. This patch adds exfat_test_bitmap_range to validate that clusters used for the allocation bitmap are correctly marked as in-use.
CVE-2025-40305 1 Linux 1 Linux Kernel 2026-04-15 7.0 High
In the Linux kernel, the following vulnerability has been resolved: 9p/trans_fd: p9_fd_request: kick rx thread if EPOLLIN p9_read_work() doesn't set Rworksched and doesn't do schedule_work(m->rq) if list_empty(&m->req_list). However, if the pipe is full, we need to read more data and this used to work prior to commit aaec5a95d59615 ("pipe_read: don't wake up the writer if the pipe is still full"). p9_read_work() does p9_fd_read() -> ... -> anon_pipe_read() which (before the commit above) triggered the unnecessary wakeup. This wakeup calls p9_pollwake() which kicks p9_poll_workfn() -> p9_poll_mux(), p9_poll_mux() will notice EPOLLIN and schedule_work(&m->rq). This no longer happens after the optimization above, change p9_fd_request() to use p9_poll_mux() instead of only checking for EPOLLOUT.
CVE-2025-40303 1 Linux 1 Linux Kernel 2026-04-15 5.5 Medium
In the Linux kernel, the following vulnerability has been resolved: btrfs: ensure no dirty metadata is written back for an fs with errors [BUG] During development of a minor feature (make sure all btrfs_bio::end_io() is called in task context), I noticed a crash in generic/388, where metadata writes triggered new works after btrfs_stop_all_workers(). It turns out that it can even happen without any code modification, just using RAID5 for metadata and the same workload from generic/388 is going to trigger the use-after-free. [CAUSE] If btrfs hits an error, the fs is marked as error, no new transaction is allowed thus metadata is in a frozen state. But there are some metadata modifications before that error, and they are still in the btree inode page cache. Since there will be no real transaction commit, all those dirty folios are just kept as is in the page cache, and they can not be invalidated by invalidate_inode_pages2() call inside close_ctree(), because they are dirty. And finally after btrfs_stop_all_workers(), we call iput() on btree inode, which triggers writeback of those dirty metadata. And if the fs is using RAID56 metadata, this will trigger RMW and queue new works into rmw_workers, which is already stopped, causing warning from queue_work() and use-after-free. [FIX] Add a special handling for write_one_eb(), that if the fs is already in an error state, immediately mark the bbio as failure, instead of really submitting them. Then during close_ctree(), iput() will just discard all those dirty tree blocks without really writing them back, thus no more new jobs for already stopped-and-freed workqueues. The extra discard in write_one_eb() also acts as an extra safenet. E.g. the transaction abort is triggered by some extent/free space tree corruptions, and since extent/free space tree is already corrupted some tree blocks may be allocated where they shouldn't be (overwriting existing tree blocks). In that case writing them back will further corrupting the fs.
CVE-2025-40301 1 Linux 1 Linux Kernel 2026-04-15 7.0 High
In the Linux kernel, the following vulnerability has been resolved: Bluetooth: hci_event: validate skb length for unknown CC opcode In hci_cmd_complete_evt(), if the command complete event has an unknown opcode, we assume the first byte of the remaining skb->data contains the return status. However, parameter data has previously been pulled in hci_event_func(), which may leave the skb empty. If so, using skb->data[0] for the return status uses un-init memory. The fix is to check skb->len before using skb->data.
CVE-2025-40299 1 Linux 1 Linux Kernel 2026-04-15 5.5 Medium
In the Linux kernel, the following vulnerability has been resolved: gve: Implement gettimex64 with -EOPNOTSUPP gve implemented a ptp_clock for sole use of do_aux_work at this time. ptp_clock_gettime() and ptp_sys_offset() assume every ptp_clock has implemented either gettimex64 or gettime64. Stub gettimex64 and return -EOPNOTSUPP to prevent NULL dereferencing.
CVE-2023-53758 1 Linux 1 Linux Kernel 2026-04-15 5.5 Medium
In the Linux kernel, the following vulnerability has been resolved: spi: atmel-quadspi: Free resources even if runtime resume failed in .remove() An early error exit in atmel_qspi_remove() doesn't prevent the device unbind. So this results in an spi controller with an unbound parent and unmapped register space (because devm_ioremap_resource() is undone). So using the remaining spi controller probably results in an oops. Instead unregister the controller unconditionally and only skip hardware access and clk disable. Also add a warning about resume failing and return zero unconditionally. The latter has the only effect to suppress a less helpful error message by the spi core.
CVE-2023-53756 1 Linux 1 Linux Kernel 2026-04-15 7.0 High
In the Linux kernel, the following vulnerability has been resolved: KVM: VMX: Fix crash due to uninitialized current_vmcs KVM enables 'Enlightened VMCS' and 'Enlightened MSR Bitmap' when running as a nested hypervisor on top of Hyper-V. When MSR bitmap is updated, evmcs_touch_msr_bitmap function uses current_vmcs per-cpu variable to mark that the msr bitmap was changed. vmx_vcpu_create() modifies the msr bitmap via vmx_disable_intercept_for_msr -> vmx_msr_bitmap_l01_changed which in the end calls this function. The function checks for current_vmcs if it is null but the check is insufficient because current_vmcs is not initialized. Because of this, the code might incorrectly write to the structure pointed by current_vmcs value left by another task. Preemption is not disabled, the current task can be preempted and moved to another CPU while current_vmcs is accessed multiple times from evmcs_touch_msr_bitmap() which leads to crash. The manipulation of MSR bitmaps by callers happens only for vmcs01 so the solution is to use vmx->vmcs01.vmcs instead of current_vmcs. BUG: kernel NULL pointer dereference, address: 0000000000000338 PGD 4e1775067 P4D 0 Oops: 0002 [#1] PREEMPT SMP NOPTI ... RIP: 0010:vmx_msr_bitmap_l01_changed+0x39/0x50 [kvm_intel] ... Call Trace: vmx_disable_intercept_for_msr+0x36/0x260 [kvm_intel] vmx_vcpu_create+0xe6/0x540 [kvm_intel] kvm_arch_vcpu_create+0x1d1/0x2e0 [kvm] kvm_vm_ioctl_create_vcpu+0x178/0x430 [kvm] kvm_vm_ioctl+0x53f/0x790 [kvm] __x64_sys_ioctl+0x8a/0xc0 do_syscall_64+0x5c/0x90 entry_SYSCALL_64_after_hwframe+0x63/0xcd
CVE-2023-53754 1 Linux 1 Linux Kernel 2026-04-15 5.5 Medium
In the Linux kernel, the following vulnerability has been resolved: scsi: lpfc: Fix ioremap issues in lpfc_sli4_pci_mem_setup() When if_type equals zero and pci_resource_start(pdev, PCI_64BIT_BAR4) returns false, drbl_regs_memmap_p is not remapped. This passes a NULL pointer to iounmap(), which can trigger a WARN() on certain arches. When if_type equals six and pci_resource_start(pdev, PCI_64BIT_BAR4) returns true, drbl_regs_memmap_p may has been remapped and ctrl_regs_memmap_p is not remapped. This is a resource leak and passes a NULL pointer to iounmap(). To fix these issues, we need to add null checks before iounmap(), and change some goto labels.
CVE-2023-53753 1 Linux 1 Linux Kernel 2026-04-15 7.0 High
In the Linux kernel, the following vulnerability has been resolved: drm/amd/display: fix mapping to non-allocated address [Why] There is an issue mapping non-allocated location of memory. It would allocate gpio registers from an array out of bounds. [How] Patch correct numbers of bounds for using.
CVE-2023-53746 1 Linux 1 Linux Kernel 2026-04-15 5.5 Medium
In the Linux kernel, the following vulnerability has been resolved: s390/vfio-ap: fix memory leak in vfio_ap device driver The device release callback function invoked to release the matrix device uses the dev_get_drvdata(device *dev) function to retrieve the pointer to the vfio_matrix_dev object in order to free its storage. The problem is, this object is not stored as drvdata with the device; since the kfree function will accept a NULL pointer, the memory for the vfio_matrix_dev object is never freed. Since the device being released is contained within the vfio_matrix_dev object, the container_of macro will be used to retrieve its pointer.
CVE-2022-50632 1 Linux 1 Linux Kernel 2026-04-15 5.5 Medium
In the Linux kernel, the following vulnerability has been resolved: drivers: perf: marvell_cn10k: Fix hotplug callback leak in tad_pmu_init() tad_pmu_init() won't remove the callback added by cpuhp_setup_state_multi() when platform_driver_register() failed. Remove the callback by cpuhp_remove_multi_state() in fail path. Similar to the handling of arm_ccn_init() in commit 26242b330093 ("bus: arm-ccn: Prevent hotplug callback leak")
CVE-2022-50630 1 Linux 1 Linux Kernel 2026-04-15 7.0 High
In the Linux kernel, the following vulnerability has been resolved: mm: hugetlb: fix UAF in hugetlb_handle_userfault The vma_lock and hugetlb_fault_mutex are dropped before handling userfault and reacquire them again after handle_userfault(), but reacquire the vma_lock could lead to UAF[1,2] due to the following race, hugetlb_fault hugetlb_no_page /*unlock vma_lock */ hugetlb_handle_userfault handle_userfault /* unlock mm->mmap_lock*/ vm_mmap_pgoff do_mmap mmap_region munmap_vma_range /* clean old vma */ /* lock vma_lock again <--- UAF */ /* unlock vma_lock */ Since the vma_lock will unlock immediately after hugetlb_handle_userfault(), let's drop the unneeded lock and unlock in hugetlb_handle_userfault() to fix the issue. [1] https://lore.kernel.org/linux-mm/000000000000d5e00a05e834962e@google.com/ [2] https://lore.kernel.org/linux-mm/20220921014457.1668-1-liuzixian4@huawei.com/
CVE-2022-50628 1 Linux 1 Linux Kernel 2026-04-15 7.0 High
In the Linux kernel, the following vulnerability has been resolved: drm/gud: Fix UBSAN warning UBSAN complains about invalid value for bool: [ 101.165172] [drm] Initialized gud 1.0.0 20200422 for 2-3.2:1.0 on minor 1 [ 101.213360] gud 2-3.2:1.0: [drm] fb1: guddrmfb frame buffer device [ 101.213426] usbcore: registered new interface driver gud [ 101.989431] ================================================================================ [ 101.989441] UBSAN: invalid-load in linux/include/linux/iosys-map.h:253:9 [ 101.989447] load of value 121 is not a valid value for type '_Bool' [ 101.989451] CPU: 1 PID: 455 Comm: kworker/1:6 Not tainted 5.18.0-rc5-gud-5.18-rc5 #3 [ 101.989456] Hardware name: Hewlett-Packard HP EliteBook 820 G1/1991, BIOS L71 Ver. 01.44 04/12/2018 [ 101.989459] Workqueue: events_long gud_flush_work [gud] [ 101.989471] Call Trace: [ 101.989474] <TASK> [ 101.989479] dump_stack_lvl+0x49/0x5f [ 101.989488] dump_stack+0x10/0x12 [ 101.989493] ubsan_epilogue+0x9/0x3b [ 101.989498] __ubsan_handle_load_invalid_value.cold+0x44/0x49 [ 101.989504] dma_buf_vmap.cold+0x38/0x3d [ 101.989511] ? find_busiest_group+0x48/0x300 [ 101.989520] drm_gem_shmem_vmap+0x76/0x1b0 [drm_shmem_helper] [ 101.989528] drm_gem_shmem_object_vmap+0x9/0xb [drm_shmem_helper] [ 101.989535] drm_gem_vmap+0x26/0x60 [drm] [ 101.989594] drm_gem_fb_vmap+0x47/0x150 [drm_kms_helper] [ 101.989630] gud_prep_flush+0xc1/0x710 [gud] [ 101.989639] ? _raw_spin_lock+0x17/0x40 [ 101.989648] gud_flush_work+0x1e0/0x430 [gud] [ 101.989653] ? __switch_to+0x11d/0x470 [ 101.989664] process_one_work+0x21f/0x3f0 [ 101.989673] worker_thread+0x200/0x3e0 [ 101.989679] ? rescuer_thread+0x390/0x390 [ 101.989684] kthread+0xfd/0x130 [ 101.989690] ? kthread_complete_and_exit+0x20/0x20 [ 101.989696] ret_from_fork+0x22/0x30 [ 101.989706] </TASK> [ 101.989708] ================================================================================ The source of this warning is in iosys_map_clear() called from dma_buf_vmap(). It conditionally sets values based on map->is_iomem. The iosys_map variables are allocated uninitialized on the stack leading to ->is_iomem having all kinds of values and not only 0/1. Fix this by zeroing the iosys_map variables.
CVE-2025-40289 1 Linux 1 Linux Kernel 2026-04-15 5.5 Medium
In the Linux kernel, the following vulnerability has been resolved: drm/amdgpu: hide VRAM sysfs attributes on GPUs without VRAM Otherwise accessing them can cause a crash.
CVE-2025-40288 1 Linux 1 Linux Kernel 2026-04-15 5.5 Medium
In the Linux kernel, the following vulnerability has been resolved: drm/amdgpu: Fix NULL pointer dereference in VRAM logic for APU devices Previously, APU platforms (and other scenarios with uninitialized VRAM managers) triggered a NULL pointer dereference in `ttm_resource_manager_usage()`. The root cause is not that the `struct ttm_resource_manager *man` pointer itself is NULL, but that `man->bdev` (the backing device pointer within the manager) remains uninitialized (NULL) on APUs—since APUs lack dedicated VRAM and do not fully set up VRAM manager structures. When `ttm_resource_manager_usage()` attempts to acquire `man->bdev->lru_lock`, it dereferences the NULL `man->bdev`, leading to a kernel OOPS. 1. **amdgpu_cs.c**: Extend the existing bandwidth control check in `amdgpu_cs_get_threshold_for_moves()` to include a check for `ttm_resource_manager_used()`. If the manager is not used (uninitialized `bdev`), return 0 for migration thresholds immediately—skipping VRAM-specific logic that would trigger the NULL dereference. 2. **amdgpu_kms.c**: Update the `AMDGPU_INFO_VRAM_USAGE` ioctl and memory info reporting to use a conditional: if the manager is used, return the real VRAM usage; otherwise, return 0. This avoids accessing `man->bdev` when it is NULL. 3. **amdgpu_virt.c**: Modify the vf2pf (virtual function to physical function) data write path. Use `ttm_resource_manager_used()` to check validity: if the manager is usable, calculate `fb_usage` from VRAM usage; otherwise, set `fb_usage` to 0 (APUs have no discrete framebuffer to report). This approach is more robust than APU-specific checks because it: - Works for all scenarios where the VRAM manager is uninitialized (not just APUs), - Aligns with TTM's design by using its native helper function, - Preserves correct behavior for discrete GPUs (which have fully initialized `man->bdev` and pass the `ttm_resource_manager_used()` check). v4: use ttm_resource_manager_used(&adev->mman.vram_mgr.manager) instead of checking the adev->gmc.is_app_apu flag (Christian)