dvb-usb: error while querying for an remote control event. ================================================================== BUG: KASAN: slab-use-after-free in __list_add_valid_or_report+0x151/0x190 lib/list_debug.c:32 Read of size 8 at addr ffff888122184250 by task kworker/1:4/26264 CPU: 1 UID: 0 PID: 26264 Comm: kworker/1:4 Not tainted syzkaller #0 PREEMPT(voluntary) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 Workqueue: events request_module_async Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:378 [inline] print_report+0xcd/0x630 mm/kasan/report.c:482 kasan_report+0xe0/0x110 mm/kasan/report.c:595 __list_add_valid_or_report+0x151/0x190 lib/list_debug.c:32 __list_add_valid include/linux/list.h:96 [inline] __list_add include/linux/list.h:158 [inline] list_add_tail include/linux/list.h:191 [inline] em28xx_init_extension+0x48/0x200 drivers/media/usb/em28xx/em28xx-core.c:1114 request_module_async+0x61/0x70 drivers/media/usb/em28xx/em28xx-cards.c:3457 process_one_work+0x9ba/0x1b20 kernel/workqueue.c:3257 process_scheduled_works kernel/workqueue.c:3340 [inline] worker_thread+0x6c8/0xf10 kernel/workqueue.c:3421 kthread+0x3c5/0x780 kernel/kthread.c:463 ret_from_fork+0x74f/0xa30 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246 Allocated by task 2863: kasan_save_stack+0x33/0x60 mm/kasan/common.c:56 kasan_save_track+0x14/0x30 mm/kasan/common.c:77 poison_kmalloc_redzone mm/kasan/common.c:397 [inline] __kasan_kmalloc+0x8f/0xa0 mm/kasan/common.c:414 kasan_kmalloc include/linux/kasan.h:262 [inline] __do_kmalloc_node mm/slub.c:5657 [inline] __kvmalloc_node_noprof+0x3b0/0xa00 mm/slub.c:7136 seq_buf_alloc fs/seq_file.c:38 [inline] seq_read_iter+0x830/0x12d0 fs/seq_file.c:210 kernfs_fop_read_iter+0x46c/0x610 fs/kernfs/file.c:297 new_sync_read fs/read_write.c:491 [inline] vfs_read+0x8bf/0xcf0 fs/read_write.c:572 ksys_read+0x12a/0x250 fs/read_write.c:715 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0x570 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f Freed by task 2863: kasan_save_stack+0x33/0x60 mm/kasan/common.c:56 kasan_save_track+0x14/0x30 mm/kasan/common.c:77 kasan_save_free_info+0x3b/0x60 mm/kasan/generic.c:584 poison_slab_object mm/kasan/common.c:252 [inline] __kasan_slab_free+0x43/0x70 mm/kasan/common.c:284 kasan_slab_free include/linux/kasan.h:234 [inline] slab_free_hook mm/slub.c:2540 [inline] slab_free mm/slub.c:6670 [inline] kfree+0x2c8/0x680 mm/slub.c:6878 seq_release+0x4b/0x80 fs/seq_file.c:355 kernfs_fop_release+0xf4/0x1e0 fs/kernfs/file.c:784 __fput+0x402/0xb70 fs/file_table.c:468 fput_close_sync+0x118/0x260 fs/file_table.c:573 __do_sys_close fs/open.c:1573 [inline] __se_sys_close fs/open.c:1558 [inline] __x64_sys_close+0x8b/0x120 fs/open.c:1558 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0x570 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f The buggy address belongs to the object at ffff888122184000 which belongs to the cache kmalloc-cg-4k of size 4096 The buggy address is located 592 bytes inside of freed 4096-byte region [ffff888122184000, ffff888122185000) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x122180 head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0 memcg:ffff88811f39a8c1 flags: 0x200000000000040(head|node=0|zone=2) page_type: f5(slab) raw: 0200000000000040 ffff88810004b500 dead000000000122 0000000000000000 raw: 0000000000000000 0000000000040004 00000000f5000000 ffff88811f39a8c1 head: 0200000000000040 ffff88810004b500 dead000000000122 0000000000000000 head: 0000000000000000 0000000000040004 00000000f5000000 ffff88811f39a8c1 head: 0200000000000003 ffffea0004886001 00000000ffffffff 00000000ffffffff head: ffff888122181f00 0000000000000000 00000000ffffffff 0000000000000008 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 3, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 2863, tgid 2863 (udevd), ts 3455987790903, free_ts 3427828063129 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x1af/0x220 mm/page_alloc.c:1846 prep_new_page mm/page_alloc.c:1854 [inline] get_page_from_freelist+0x1058/0x3cb0 mm/page_alloc.c:3915 __alloc_frozen_pages_noprof+0x259/0x21c0 mm/page_alloc.c:5210 alloc_pages_mpol+0xe4/0x410 mm/mempolicy.c:2486 alloc_slab_page mm/slub.c:3075 [inline] allocate_slab mm/slub.c:3248 [inline] new_slab+0x2c3/0x430 mm/slub.c:3302 ___slab_alloc+0xe20/0x1ca0 mm/slub.c:4656 __slab_alloc.constprop.0+0x63/0x110 mm/slub.c:4779 __slab_alloc_node mm/slub.c:4855 [inline] slab_alloc_node mm/slub.c:5251 [inline] __do_kmalloc_node mm/slub.c:5656 [inline] __kvmalloc_node_noprof+0x548/0xa00 mm/slub.c:7136 seq_buf_alloc fs/seq_file.c:38 [inline] seq_read_iter+0x830/0x12d0 fs/seq_file.c:210 kernfs_fop_read_iter+0x46c/0x610 fs/kernfs/file.c:297 new_sync_read fs/read_write.c:491 [inline] vfs_read+0x8bf/0xcf0 fs/read_write.c:572 ksys_read+0x12a/0x250 fs/read_write.c:715 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0x570 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f page last free pid 14 tgid 14 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1395 [inline] __free_frozen_pages+0x795/0x1010 mm/page_alloc.c:2943 __pagetable_free include/linux/mm.h:3200 [inline] pagetable_free include/linux/mm.h:3224 [inline] pagetable_dtor_free include/linux/mm.h:3328 [inline] __tlb_remove_table include/asm-generic/tlb.h:220 [inline] __tlb_remove_table_free mm/mmu_gather.c:227 [inline] tlb_remove_table_rcu+0x2b2/0x390 mm/mmu_gather.c:290 rcu_do_batch kernel/rcu/tree.c:2605 [inline] rcu_core+0x79c/0x15f0 kernel/rcu/tree.c:2857 handle_softirqs+0x208/0x940 kernel/softirq.c:622 run_ksoftirqd kernel/softirq.c:1063 [inline] run_ksoftirqd+0x3a/0x60 kernel/softirq.c:1055 smpboot_thread_fn+0x3f7/0xae0 kernel/smpboot.c:160 kthread+0x3c5/0x780 kernel/kthread.c:463 ret_from_fork+0x74f/0xa30 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: ffff888122184100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888122184180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff888122184200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888122184280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888122184300: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================