================================================================== BUG: KASAN: use-after-free in read_pnet include/net/net_namespace.h:419 [inline] BUG: KASAN: use-after-free in dev_net include/linux/netdevice.h:2741 [inline] BUG: KASAN: use-after-free in nf_hook_entry_head+0x1f1/0x2c0 net/netfilter/core.c:319 Read of size 8 at addr ffff888090ed4108 by task kworker/u8:5/133 CPU: 1 UID: 0 PID: 133 Comm: kworker/u8:5 Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026 Workqueue: netns cleanup_net 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 read_pnet include/net/net_namespace.h:419 [inline] dev_net include/linux/netdevice.h:2741 [inline] nf_hook_entry_head+0x1f1/0x2c0 net/netfilter/core.c:319 __nf_unregister_net_hook+0x74/0x6f0 net/netfilter/core.c:491 nft_unregister_flowtable_ops net/netfilter/nf_tables_api.c:9059 [inline] __nft_unregister_flowtable_net_hooks net/netfilter/nf_tables_api.c:9074 [inline] __nft_release_hook net/netfilter/nf_tables_api.c:12063 [inline] __nft_release_hooks net/netfilter/nf_tables_api.c:12077 [inline] nf_tables_pre_exit_net+0x64a/0x900 net/netfilter/nf_tables_api.c:12228 ops_pre_exit_list net/core/net_namespace.c:161 [inline] ops_undo_list+0x187/0x940 net/core/net_namespace.c:234 cleanup_net+0x56b/0x800 net/core/net_namespace.c:704 process_one_work kernel/workqueue.c:3275 [inline] process_scheduled_works+0xb02/0x1830 kernel/workqueue.c:3358 worker_thread+0xa50/0xfc0 kernel/workqueue.c:3439 kthread+0x388/0x470 kernel/kthread.c:467 ret_from_fork+0x51e/0xb90 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x9f1c pfn:0x90ed4 flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff) page_type: f0(buddy) raw: 00fff00000000000 ffffea0001f54708 ffffea0001ea2d08 0000000000000000 raw: 0000000000009f1c 0000000000000002 00000000f0000000 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as freed page last allocated via order 0, migratetype Unmovable, gfp_mask 0x146cc2(GFP_HIGHUSER|__GFP_NOWARN|__GFP_RETRY_MAYFAIL|__GFP_COMP), pid 30453, tgid 30445 (syz.2.7736), ts 1195646523409, free_ts 1201494424191 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x231/0x280 mm/page_alloc.c:1888 prep_new_page mm/page_alloc.c:1896 [inline] get_page_from_freelist+0x24dc/0x2580 mm/page_alloc.c:3961 __alloc_frozen_pages_noprof+0x18d/0x380 mm/page_alloc.c:5249 alloc_pages_mpol+0x232/0x4a0 mm/mempolicy.c:2485 folio_alloc_mpol_noprof+0x39/0x70 mm/mempolicy.c:2504 shmem_alloc_folio mm/shmem.c:1930 [inline] shmem_alloc_and_add_folio+0x445/0xf80 mm/shmem.c:1972 shmem_get_folio_gfp+0x5a9/0x1670 mm/shmem.c:2567 shmem_read_folio_gfp+0x8a/0xe0 mm/shmem.c:5982 drm_gem_get_pages+0x26c/0xab0 drivers/gpu/drm/drm_gem.c:695 drm_gem_shmem_get_pages_locked+0x22b/0x480 drivers/gpu/drm/drm_gem_shmem_helper.c:222 drm_gem_shmem_mmap+0x193/0x440 drivers/gpu/drm/drm_gem_shmem_helper.c:688 drm_gem_mmap_obj+0x18a/0x4c0 drivers/gpu/drm/drm_gem.c:1208 drm_gem_mmap+0xc5/0x1a0 drivers/gpu/drm/drm_gem.c:1351 vfs_mmap include/linux/fs.h:2070 [inline] mmap_file mm/internal.h:167 [inline] __mmap_new_file_vma mm/vma.c:2462 [inline] __mmap_new_vma mm/vma.c:2525 [inline] __mmap_region mm/vma.c:2752 [inline] mmap_region+0x1787/0x1f50 mm/vma.c:2830 do_mmap+0xc39/0x10c0 mm/mmap.c:558 vm_mmap_pgoff+0x2c9/0x4f0 mm/util.c:581 page last free pid 30453 tgid 30445 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] __free_pages_prepare mm/page_alloc.c:1432 [inline] free_unref_folios+0xd38/0x14c0 mm/page_alloc.c:3039 folios_put_refs+0x789/0x8d0 mm/swap.c:1002 folio_batch_release include/linux/pagevec.h:101 [inline] shmem_undo_range+0x52c/0x1660 mm/shmem.c:1149 shmem_truncate_range mm/shmem.c:1277 [inline] shmem_evict_inode+0x240/0x9e0 mm/shmem.c:1407 evict+0x61e/0xb10 fs/inode.c:846 __dentry_kill+0x1a2/0x5e0 fs/dcache.c:670 finish_dput+0xc9/0x480 fs/dcache.c:879 __fput+0x691/0xa70 fs/file_table.c:477 task_work_run+0x1d9/0x270 kernel/task_work.c:233 exit_task_work include/linux/task_work.h:40 [inline] do_exit+0x69b/0x2320 kernel/exit.c:971 do_group_exit+0x21b/0x2d0 kernel/exit.c:1112 get_signal+0x1284/0x1330 kernel/signal.c:3034 arch_do_signal_or_restart+0xbc/0x830 arch/x86/kernel/signal.c:337 __exit_to_user_mode_loop kernel/entry/common.c:64 [inline] exit_to_user_mode_loop+0x86/0x480 kernel/entry/common.c:98 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:226 [inline] syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:256 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:325 [inline] do_syscall_64+0x32d/0xf80 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f Memory state around the buggy address: ffff888090ed4000: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ffff888090ed4080: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff >ffff888090ed4100: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ^ ffff888090ed4180: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ffff888090ed4200: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ==================================================================