================================================================== BUG: KASAN: slab-use-after-free in vidtv_bridge_check_demod_lock drivers/media/test-drivers/vidtv/vidtv_bridge.c:145 [inline] BUG: KASAN: slab-use-after-free in vidtv_bridge_on_new_pkts_avail+0xc0/0x154 drivers/media/test-drivers/vidtv/vidtv_bridge.c:162 Read of size 8 at addr ffff0000cb2ab118 by task kworker/0:6/5601 CPU: 0 UID: 0 PID: 5601 Comm: kworker/0:6 Tainted: G L syzkaller #0 PREEMPT Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/07/2026 Workqueue: events vidtv_mux_tick Call trace: show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:499 (C) __dump_stack+0x30/0x40 lib/dump_stack.c:94 dump_stack_lvl+0xd8/0x12c lib/dump_stack.c:120 print_address_description+0xb0/0x238 mm/kasan/report.c:378 print_report+0x68/0x84 mm/kasan/report.c:482 kasan_report+0x8c/0xc4 mm/kasan/report.c:595 __asan_report_load8_noabort+0x20/0x2c mm/kasan/report_generic.c:381 vidtv_bridge_check_demod_lock drivers/media/test-drivers/vidtv/vidtv_bridge.c:145 [inline] vidtv_bridge_on_new_pkts_avail+0xc0/0x154 drivers/media/test-drivers/vidtv/vidtv_bridge.c:162 vidtv_mux_tick+0x15e4/0x1b60 drivers/media/test-drivers/vidtv/vidtv_mux.c:426 process_one_work kernel/workqueue.c:3322 [inline] process_scheduled_works+0x788/0x10b8 kernel/workqueue.c:3405 worker_thread+0x798/0xbd0 kernel/workqueue.c:3486 kthread+0x304/0x3d4 kernel/kthread.c:436 ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:838 Allocated by task 1: kasan_save_stack mm/kasan/common.c:57 [inline] kasan_save_track+0x40/0x78 mm/kasan/common.c:78 kasan_save_alloc_info+0x40/0x50 mm/kasan/generic.c:570 poison_kmalloc_redzone mm/kasan/common.c:398 [inline] __kasan_kmalloc+0x9c/0xb4 mm/kasan/common.c:415 kasan_kmalloc include/linux/kasan.h:263 [inline] __kmalloc_cache_noprof+0x2e8/0x5ec mm/slub.c:5489 _kmalloc_noprof include/linux/slab.h:988 [inline] _kzalloc_noprof include/linux/slab.h:1309 [inline] vidtv_demod_i2c_probe+0x78/0x6b0 drivers/media/test-drivers/vidtv/vidtv_demod.c:421 i2c_device_probe+0x848/0x9d4 drivers/i2c/i2c-core-base.c:592 call_driver_probe drivers/base/dd.c:-1 [inline] really_probe+0x29c/0x800 drivers/base/dd.c:706 __driver_probe_device+0x1e0/0x350 drivers/base/dd.c:868 driver_probe_device+0x6c/0x19c drivers/base/dd.c:898 __device_attach_driver+0x198/0x2f8 drivers/base/dd.c:1026 bus_for_each_drv+0x144/0x1dc drivers/base/bus.c:500 __device_attach+0x248/0x390 drivers/base/dd.c:1098 device_initial_probe+0x90/0xc8 drivers/base/dd.c:1153 bus_probe_device+0x58/0x120 drivers/base/bus.c:620 device_add+0x6cc/0x9e0 drivers/base/core.c:3772 device_register+0x28/0x38 drivers/base/core.c:3854 i2c_new_client_device+0x5ac/0xadc drivers/i2c/i2c-core-base.c:1019 dvb_module_probe+0x194/0x2c0 drivers/media/dvb-core/dvbdev.c:1039 vidtv_bridge_probe_demod drivers/media/test-drivers/vidtv/vidtv_bridge.c:354 [inline] vidtv_bridge_dvb_init drivers/media/test-drivers/vidtv/vidtv_bridge.c:430 [inline] vidtv_bridge_probe+0x368/0xa58 drivers/media/test-drivers/vidtv/vidtv_bridge.c:510 platform_probe+0x100/0x1a4 drivers/base/platform.c:1439 call_driver_probe drivers/base/dd.c:-1 [inline] really_probe+0x29c/0x800 drivers/base/dd.c:706 __driver_probe_device+0x1e0/0x350 drivers/base/dd.c:868 driver_probe_device+0x6c/0x19c drivers/base/dd.c:898 __driver_attach+0x168/0x384 drivers/base/dd.c:1292 bus_for_each_dev+0x128/0x1b4 drivers/base/bus.c:383 driver_attach+0x50/0x60 drivers/base/dd.c:1310 bus_add_driver+0x208/0x500 drivers/base/bus.c:763 driver_register+0x220/0x310 drivers/base/driver.c:174 __platform_driver_register+0x90/0xa4 drivers/base/platform.c:927 vidtv_bridge_init+0x4c/0x74 drivers/media/test-drivers/vidtv/vidtv_bridge.c:602 do_one_initcall+0x274/0xc38 init/main.c:1347 do_initcall_level+0x12c/0x1c4 init/main.c:1409 do_initcalls+0x70/0xd0 init/main.c:1425 do_basic_setup+0x7c/0x90 init/main.c:1445 kernel_init_freeable+0x268/0x3a8 init/main.c:1658 kernel_init+0x24/0x1dc init/main.c:1548 ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:838 Freed by task 7986: kasan_save_stack mm/kasan/common.c:57 [inline] kasan_save_track+0x40/0x78 mm/kasan/common.c:78 kasan_save_free_info+0x54/0x6c mm/kasan/generic.c:584 poison_slab_object mm/kasan/common.c:253 [inline] __kasan_slab_free+0x74/0xa4 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+0x188/0x690 mm/slub.c:6692 vidtv_demod_i2c_remove+0x40/0x50 drivers/media/test-drivers/vidtv/vidtv_demod.c:444 i2c_device_remove+0x8c/0x1f8 drivers/i2c/i2c-core-base.c:631 device_remove+0xc4/0x134 drivers/base/dd.c:616 __device_release_driver drivers/base/dd.c:1349 [inline] device_release_driver_internal+0x124/0x20c drivers/base/dd.c:1372 device_release_driver+0x28/0x38 drivers/base/dd.c:1395 bus_remove_device+0x2d0/0x400 drivers/base/bus.c:664 device_del+0x3ec/0x71c drivers/base/core.c:3961 device_unregister+0x2c/0xf0 drivers/base/core.c:4002 i2c_unregister_device+0x1a8/0x1fc drivers/i2c/i2c-core-base.c:1075 dvb_module_release+0x70/0x8c drivers/media/dvb-core/dvbdev.c:1061 vidtv_bridge_remove+0xcc/0x10c drivers/media/test-drivers/vidtv/vidtv_bridge.c:556 platform_remove+0x6c/0x88 drivers/base/platform.c:1456 device_remove+0xc4/0x134 drivers/base/dd.c:616 __device_release_driver drivers/base/dd.c:1349 [inline] device_release_driver_internal+0x124/0x20c drivers/base/dd.c:1372 device_driver_detach+0x48/0x58 drivers/base/dd.c:1408 unbind_store+0xc0/0xf0 drivers/base/bus.c:244 drv_attr_store+0x80/0xa4 drivers/base/bus.c:125 sysfs_kf_write+0xe0/0x108 fs/sysfs/file.c:145 kernfs_fop_write_iter+0x260/0x3b8 fs/kernfs/file.c:345 new_sync_write fs/read_write.c:595 [inline] vfs_write+0x51c/0xa0c fs/read_write.c:687 ksys_write+0x12c/0x228 fs/read_write.c:739 __do_sys_write fs/read_write.c:750 [inline] __se_sys_write fs/read_write.c:747 [inline] __arm64_sys_write+0x84/0x98 fs/read_write.c:747 __invoke_syscall arch/arm64/kernel/syscall.c:35 [inline] invoke_syscall+0x98/0x244 arch/arm64/kernel/syscall.c:49 el0_svc_common+0xec/0x23c arch/arm64/kernel/syscall.c:121 do_el0_svc+0x4c/0x5c arch/arm64/kernel/syscall.c:140 el0_svc+0x64/0x260 arch/arm64/kernel/entry-common.c:758 el0t_64_sync_handler+0x44/0x104 arch/arm64/kernel/entry-common.c:777 el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:590 The buggy address belongs to the object at ffff0000cb2ab000 which belongs to the cache kmalloc-2k of size 2048 The buggy address is located 280 bytes inside of freed 2048-byte region [ffff0000cb2ab000, ffff0000cb2ab800) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x10b2a8 head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0 flags: 0x5ffc00000000040(head|node=0|zone=2|lastcpupid=0x7ff) page_type: f5(slab) raw: 05ffc00000000040 ffff0000c0002000 dead000000000100 dead000000000122 raw: 0000000000000000 0000000800080008 00000000f5000000 0000000000000000 head: 05ffc00000000040 ffff0000c0002000 dead000000000100 dead000000000122 head: 0000000000000000 0000000800080008 00000000f5000000 0000000000000000 head: 05ffc00000000003 fffffdffc32caa01 00000000ffffffff 00000000ffffffff head: ffffffffffffffff 0000000000000000 00000000ffffffff 0000000000000008 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff0000cb2ab000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff0000cb2ab080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff0000cb2ab100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff0000cb2ab180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff0000cb2ab200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================