================================================================== BUG: KASAN: use-after-free in v4l2_fh_init drivers/media/v4l2-core/v4l2-fh.c:25 [inline] BUG: KASAN: use-after-free in v4l2_fh_open+0xc6/0x430 drivers/media/v4l2-core/v4l2-fh.c:63 Read of size 8 at addr ffff88805c3e0900 by task v4l_id/4358 CPU: 1 PID: 4358 Comm: v4l_id Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026 Call Trace: dump_stack_lvl+0x188/0x250 lib/dump_stack.c:106 print_address_description+0x60/0x2d0 mm/kasan/report.c:248 __kasan_report mm/kasan/report.c:434 [inline] kasan_report+0xdf/0x130 mm/kasan/report.c:451 v4l2_fh_init drivers/media/v4l2-core/v4l2-fh.c:25 [inline] v4l2_fh_open+0xc6/0x430 drivers/media/v4l2-core/v4l2-fh.c:63 em28xx_v4l2_open+0x152/0x990 drivers/media/usb/em28xx/em28xx-video.c:2163 v4l2_open+0x20b/0x360 drivers/media/v4l2-core/v4l2-dev.c:427 chrdev_open+0x5c5/0x6a0 fs/char_dev.c:414 do_dentry_open+0x7ff/0xf80 fs/open.c:826 do_open fs/namei.c:3616 [inline] path_openat+0x26f5/0x2fa0 fs/namei.c:3750 do_filp_open+0x1e2/0x410 fs/namei.c:3777 do_sys_openat2+0x150/0x4b0 fs/open.c:1255 do_sys_open fs/open.c:1271 [inline] __do_sys_openat fs/open.c:1287 [inline] __se_sys_openat fs/open.c:1282 [inline] __x64_sys_openat+0x135/0x160 fs/open.c:1282 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 RIP: 0033:0x7f9780fa2407 Code: 48 89 fa 4c 89 df e8 38 aa 00 00 8b 93 08 03 00 00 59 5e 48 83 f8 fc 74 1a 5b c3 0f 1f 84 00 00 00 00 00 48 8b 44 24 10 0f 05 <5b> c3 0f 1f 80 00 00 00 00 83 e2 39 83 fa 08 75 de e8 23 ff ff ff RSP: 002b:00007ffc3bc4e8f0 EFLAGS: 00000202 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 00007f9780eb4880 RCX: 00007f9780fa2407 RDX: 0000000000000000 RSI: 00007ffc3bc4ff1c RDI: ffffffffffffff9c RBP: 0000000000000002 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000000 R13: 00007ffc3bc4eb40 R14: 00007f9781730000 R15: 0000563d759054d8 The buggy address belongs to the page: page:ffffea000170f800 refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x5c3e0 flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000000000 ffffea00016faa08 ffff8880b90409f0 0000000000000000 raw: 0000000000000000 0000000000000000 00000000ffffffff 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as freed page last allocated via order 2, migratetype Unmovable, gfp_mask 0x102020(__GFP_HIGH|__GFP_NOWARN|__GFP_HARDWALL), pid 9, ts 57721206798, free_ts 57721211454 prep_new_page mm/page_alloc.c:2426 [inline] get_page_from_freelist+0x1bbd/0x1ca0 mm/page_alloc.c:4192 __alloc_pages+0x1ee/0x480 mm/page_alloc.c:5501 stack_depot_save+0x342/0x440 lib/stackdepot.c:302 kasan_save_stack mm/kasan/common.c:40 [inline] kasan_set_track mm/kasan/common.c:46 [inline] set_alloc_info mm/kasan/common.c:434 [inline] __kasan_slab_alloc+0xb3/0xd0 mm/kasan/common.c:467 kasan_slab_alloc include/linux/kasan.h:254 [inline] slab_post_alloc_hook+0x4c/0x380 mm/slab.h:519 slab_alloc_node mm/slub.c:3225 [inline] slab_alloc mm/slub.c:3233 [inline] kmem_cache_alloc+0x100/0x290 mm/slub.c:3238 kmem_cache_zalloc include/linux/slab.h:728 [inline] fill_pool lib/debugobjects.c:172 [inline] __debug_object_init+0x854/0xc80 lib/debugobjects.c:615 debug_timer_init kernel/time/timer.c:724 [inline] debug_init kernel/time/timer.c:772 [inline] init_timer_key+0x3d/0x2a0 kernel/time/timer.c:816 ipv6_add_addr+0x68a/0xe10 net/ipv6/addrconf.c:1137 addrconf_add_linklocal+0x26a/0x6c0 net/ipv6/addrconf.c:3238 addrconf_addr_gen+0x559/0x6b0 net/ipv6/addrconf.c:3369 addrconf_init_auto_addrs+0x747/0xb00 net/ipv6/addrconf.c:-1 addrconf_notify+0xa6b/0xf00 net/ipv6/addrconf.c:3662 notifier_call_chain kernel/notifier.c:83 [inline] raw_notifier_call_chain+0xcb/0x160 kernel/notifier.c:391 netdev_state_change+0xe0/0x160 net/core/dev.c:1453 linkwatch_do_dev+0x10d/0x160 net/core/link_watch.c:167 page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1340 [inline] free_pcp_prepare mm/page_alloc.c:1391 [inline] free_unref_page_prepare+0x637/0x6c0 mm/page_alloc.c:3317 free_unref_page+0x8f/0x2a0 mm/page_alloc.c:3396 stack_depot_save+0x418/0x440 lib/stackdepot.c:335 kasan_save_stack mm/kasan/common.c:40 [inline] kasan_set_track mm/kasan/common.c:46 [inline] set_alloc_info mm/kasan/common.c:434 [inline] __kasan_slab_alloc+0xb3/0xd0 mm/kasan/common.c:467 kasan_slab_alloc include/linux/kasan.h:254 [inline] slab_post_alloc_hook+0x4c/0x380 mm/slab.h:519 slab_alloc_node mm/slub.c:3225 [inline] slab_alloc mm/slub.c:3233 [inline] kmem_cache_alloc+0x100/0x290 mm/slub.c:3238 kmem_cache_zalloc include/linux/slab.h:728 [inline] fill_pool lib/debugobjects.c:172 [inline] __debug_object_init+0x854/0xc80 lib/debugobjects.c:615 debug_timer_init kernel/time/timer.c:724 [inline] debug_init kernel/time/timer.c:772 [inline] init_timer_key+0x3d/0x2a0 kernel/time/timer.c:816 ipv6_add_addr+0x68a/0xe10 net/ipv6/addrconf.c:1137 addrconf_add_linklocal+0x26a/0x6c0 net/ipv6/addrconf.c:3238 addrconf_addr_gen+0x559/0x6b0 net/ipv6/addrconf.c:3369 addrconf_init_auto_addrs+0x747/0xb00 net/ipv6/addrconf.c:-1 addrconf_notify+0xa6b/0xf00 net/ipv6/addrconf.c:3662 notifier_call_chain kernel/notifier.c:83 [inline] raw_notifier_call_chain+0xcb/0x160 kernel/notifier.c:391 netdev_state_change+0xe0/0x160 net/core/dev.c:1453 linkwatch_do_dev+0x10d/0x160 net/core/link_watch.c:167 Memory state around the buggy address: ffff88805c3e0800: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ffff88805c3e0880: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff >ffff88805c3e0900: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ^ ffff88805c3e0980: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ffff88805c3e0a00: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff 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