================================================================== 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 ffff88805e684900 by task v4l_id/4436 CPU: 0 PID: 4436 Comm: v4l_id Not tainted 5.15.184-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 Call Trace: dump_stack_lvl+0x168/0x230 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+0x597/0x670 fs/char_dev.c:414 do_dentry_open+0x7ff/0xf80 fs/open.c:826 do_open fs/namei.c:3608 [inline] path_openat+0x2682/0x2f30 fs/namei.c:3742 do_filp_open+0x1b3/0x3e0 fs/namei.c:3769 do_sys_openat2+0x142/0x4a0 fs/open.c:1253 do_sys_open fs/open.c:1269 [inline] __do_sys_openat fs/open.c:1285 [inline] __se_sys_openat fs/open.c:1280 [inline] __x64_sys_openat+0x135/0x160 fs/open.c:1280 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: 0033:0x7f79fb2fd407 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:00007fff8b607df0 EFLAGS: 00000202 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 00007f79fb20f880 RCX: 00007f79fb2fd407 RDX: 0000000000000000 RSI: 00007fff8b609f1c RDI: ffffffffffffff9c RBP: 0000000000000002 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000000 R13: 00007fff8b608040 R14: 00007f79fba8b000 R15: 000055ed3a59d4d8 The buggy address belongs to the page: page:ffffea000179a100 refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x5e684 flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000000000 ffffea0001e4df08 ffff8880b91409b0 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 0x102800(GFP_NOWAIT|__GFP_NOWARN|__GFP_HARDWALL), pid 4412, ts 87039366215, free_ts 87039372738 prep_new_page mm/page_alloc.c:2426 [inline] get_page_from_freelist+0x1b77/0x1c60 mm/page_alloc.c:4192 __alloc_pages+0x1e1/0x470 mm/page_alloc.c:5466 stack_depot_save+0x342/0x440 lib/stackdepot.c:302 kasan_save_stack mm/kasan/common.c:40 [inline] kasan_set_track+0x62/0x70 mm/kasan/common.c:46 kasan_set_free_info+0x1f/0x40 mm/kasan/generic.c:360 ____kasan_slab_free+0xd5/0x110 mm/kasan/common.c:366 kasan_slab_free include/linux/kasan.h:230 [inline] slab_free_hook mm/slub.c:1705 [inline] slab_free_freelist_hook+0xea/0x170 mm/slub.c:1731 slab_free mm/slub.c:3499 [inline] kfree+0xef/0x2a0 mm/slub.c:4559 do_balance_completed fs/reiserfs/do_balan.c:1824 [inline] do_balance+0x559/0x930 fs/reiserfs/do_balan.c:1899 reiserfs_paste_into_item+0x69b/0x7e0 fs/reiserfs/stree.c:2159 reiserfs_get_block+0x1bde/0x4100 fs/reiserfs/inode.c:1077 __block_write_begin_int+0x54e/0x15a0 fs/buffer.c:2012 reiserfs_write_begin+0x34b/0x810 fs/reiserfs/inode.c:2790 generic_cont_expand_simple+0xe9/0x190 fs/buffer.c:2362 reiserfs_setattr+0x42f/0x1010 fs/reiserfs/inode.c:3319 notify_change+0xbcd/0xee0 fs/attr.c:505 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+0x94/0x280 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+0x62/0x70 mm/kasan/common.c:46 kasan_set_free_info+0x1f/0x40 mm/kasan/generic.c:360 ____kasan_slab_free+0xd5/0x110 mm/kasan/common.c:366 kasan_slab_free include/linux/kasan.h:230 [inline] slab_free_hook mm/slub.c:1705 [inline] slab_free_freelist_hook+0xea/0x170 mm/slub.c:1731 slab_free mm/slub.c:3499 [inline] kfree+0xef/0x2a0 mm/slub.c:4559 do_balance_completed fs/reiserfs/do_balan.c:1824 [inline] do_balance+0x559/0x930 fs/reiserfs/do_balan.c:1899 reiserfs_paste_into_item+0x69b/0x7e0 fs/reiserfs/stree.c:2159 reiserfs_get_block+0x1bde/0x4100 fs/reiserfs/inode.c:1077 __block_write_begin_int+0x54e/0x15a0 fs/buffer.c:2012 reiserfs_write_begin+0x34b/0x810 fs/reiserfs/inode.c:2790 generic_cont_expand_simple+0xe9/0x190 fs/buffer.c:2362 reiserfs_setattr+0x42f/0x1010 fs/reiserfs/inode.c:3319 notify_change+0xbcd/0xee0 fs/attr.c:505 Memory state around the buggy address: ffff88805e684800: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ffff88805e684880: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff >ffff88805e684900: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ^ ffff88805e684980: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ffff88805e684a00: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ==================================================================