netlink: 'syz.1.9102': attribute type 1 has an invalid length. ================================================================== BUG: KASAN: stack-out-of-bounds in get_upper_ifindexes kernel/bpf/devmap.c:601 [inline] BUG: KASAN: stack-out-of-bounds in dev_map_redirect_multi+0x1bb/0xa00 kernel/bpf/devmap.c:736 Write of size 4 at addr ffffc9000b117164 by task syz.1.9102/9450 CPU: 1 UID: 0 PID: 9450 Comm: syz.1.9102 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/24/2026 Call Trace: dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:378 [inline] print_report+0xba/0x230 mm/kasan/report.c:482 kasan_report+0x117/0x150 mm/kasan/report.c:595 get_upper_ifindexes kernel/bpf/devmap.c:601 [inline] dev_map_redirect_multi+0x1bb/0xa00 kernel/bpf/devmap.c:736 xdp_do_generic_redirect_map net/core/filter.c:4556 [inline] xdp_do_generic_redirect+0x669/0x820 net/core/filter.c:4619 do_xdp_generic+0xcf7/0x12e0 net/core/dev.c:5612 __netif_receive_skb_core+0x10e5/0x3150 net/core/dev.c:5961 __netif_receive_skb_one_core net/core/dev.c:6149 [inline] __netif_receive_skb net/core/dev.c:6264 [inline] netif_receive_skb_internal net/core/dev.c:6350 [inline] netif_receive_skb+0x1fe/0xbb0 net/core/dev.c:6409 tun_rx_batched+0x1de/0x790 drivers/net/tun.c:1485 tun_get_user+0x2a78/0x3dd0 drivers/net/tun.c:1953 tun_chr_write_iter+0x113/0x200 drivers/net/tun.c:1999 new_sync_write fs/read_write.c:593 [inline] vfs_write+0x61d/0xb90 fs/read_write.c:686 ksys_write+0x150/0x270 fs/read_write.c:738 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xe2/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f937215b78e Code: 08 0f 85 a5 a8 ff ff 49 89 fb 48 89 f0 48 89 d7 48 89 ce 4c 89 c2 4d 89 ca 4c 8b 44 24 08 4c 8b 4c 24 10 4c 89 5c 24 08 0f 05 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 80 00 00 00 00 48 83 ec 08 RSP: 002b:00007f9372ffafb8 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007f9372ffb6c0 RCX: 00007f937215b78e RDX: 0000000000000086 RSI: 0000200000000780 RDI: 00000000000000c8 RBP: 00007f9372208c1f R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f9372416038 R14: 00007f9372415fa0 R15: 00007fffe06ef058 The buggy address belongs to stack of task syz.1.9102/9450 and is located at offset 100 in frame: dev_map_redirect_multi+0x0/0xa00 include/linux/skbuff.h:2833 This frame has 2 objects: [32, 40) 'iter.i' [64, 100) 'excluded_devices' The buggy address belongs to a 8-page vmalloc region starting at 0xffffc9000b110000 allocated at copy_process+0x508/0x3980 kernel/fork.c:2052 The buggy address belongs to the physical page: page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x94807 memcg:ffff88814237e782 flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000000000 0000000000000000 dead000000000122 0000000000000000 raw: 0000000000000000 0000000000000000 00000001ffffffff ffff88814237e782 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 0, migratetype Unmovable, gfp_mask 0x29c2(GFP_NOWAIT|__GFP_HIGHMEM|__GFP_IO|__GFP_FS|__GFP_ZERO), pid 2, tgid 2 (kthreadd), ts 1433078116205, free_ts 1432956594052 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x228/0x280 mm/page_alloc.c:1884 prep_new_page mm/page_alloc.c:1892 [inline] get_page_from_freelist+0x24dc/0x2580 mm/page_alloc.c:3945 __alloc_frozen_pages_noprof+0x18d/0x380 mm/page_alloc.c:5240 alloc_pages_mpol+0x232/0x4a0 mm/mempolicy.c:2486 alloc_frozen_pages_noprof mm/mempolicy.c:2557 [inline] alloc_pages_noprof+0xa8/0x190 mm/mempolicy.c:2577 vm_area_alloc_pages mm/vmalloc.c:3649 [inline] __vmalloc_area_node mm/vmalloc.c:3863 [inline] __vmalloc_node_range_noprof+0x79b/0x1730 mm/vmalloc.c:4051 __vmalloc_node_noprof+0xc2/0x100 mm/vmalloc.c:4111 alloc_thread_stack_node kernel/fork.c:354 [inline] dup_task_struct+0x228/0x9a0 kernel/fork.c:923 copy_process+0x508/0x3980 kernel/fork.c:2052 kernel_clone+0x248/0x870 kernel/fork.c:2651 kernel_thread+0x13f/0x1b0 kernel/fork.c:2712 create_kthread kernel/kthread.c:486 [inline] kthreadd+0x4f9/0x6f0 kernel/kthread.c:844 ret_from_fork+0x51b/0xa40 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246 page last free pid 8089 tgid 8089 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1433 [inline] __free_frozen_pages+0xbf8/0xd70 mm/page_alloc.c:2973 __folio_put+0x414/0x4f0 mm/swap.c:112 put_netmem include/net/netmem.h:420 [inline] skb_page_unref include/linux/skbuff_ref.h:43 [inline] __skb_frag_unref include/linux/skbuff_ref.h:56 [inline] skb_release_data+0x4cb/0x940 net/core/skbuff.c:1122 skb_release_all net/core/skbuff.c:1203 [inline] __kfree_skb+0x5d/0x210 net/core/skbuff.c:1217 kfree_skb_reason include/linux/skbuff.h:1322 [inline] __skb_queue_purge_reason include/linux/skbuff.h:3426 [inline] __skb_queue_purge include/linux/skbuff.h:3431 [inline] virtio_transport_remove_sock net/vmw_vsock/virtio_transport_common.c:1224 [inline] virtio_transport_cancel_close_work net/vmw_vsock/virtio_transport_common.c:1237 [inline] virtio_transport_do_close+0x251/0x3c0 net/vmw_vsock/virtio_transport_common.c:1255 virtio_transport_recv_connected+0x3c4/0xf10 net/vmw_vsock/virtio_transport_common.c:1464 virtio_transport_recv_pkt+0x17a4/0x2b70 net/vmw_vsock/virtio_transport_common.c:1693 vsock_loopback_work+0x32c/0x3f0 net/vmw_vsock/vsock_loopback.c:142 process_one_work kernel/workqueue.c:3257 [inline] process_scheduled_works+0xaec/0x17a0 kernel/workqueue.c:3340 worker_thread+0xda6/0x1360 kernel/workqueue.c:3421 kthread+0x726/0x8b0 kernel/kthread.c:463 ret_from_fork+0x51b/0xa40 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246 Memory state around the buggy address: ffffc9000b117000: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffffc9000b117080: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 >ffffc9000b117100: f1 f1 f1 f1 00 f2 f2 f2 00 00 00 00 04 f3 f3 f3 ^ ffffc9000b117180: f3 f3 f3 f3 00 00 00 00 00 00 00 00 00 00 00 00 ffffc9000b117200: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ==================================================================