================================================================== BUG: KASAN: slab-use-after-free in v4l2_fh_init+0x27d/0x2c0 drivers/media/v4l2-core/v4l2-fh.c:25 Read of size 8 at addr ffff88807e700738 by task v4l_id/6074 CPU: 1 UID: 0 PID: 6074 Comm: v4l_id Not tainted 6.13.0-syzkaller-09760-g69e858e0b8b2 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024 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+0xc3/0x620 mm/kasan/report.c:489 kasan_report+0xd9/0x110 mm/kasan/report.c:602 v4l2_fh_init+0x27d/0x2c0 drivers/media/v4l2-core/v4l2-fh.c:25 v4l2_fh_open+0x83/0xc0 drivers/media/v4l2-core/v4l2-fh.c:63 em28xx_v4l2_open+0x250/0x7e0 drivers/media/usb/em28xx/em28xx-video.c:2153 v4l2_open+0x222/0x490 drivers/media/v4l2-core/v4l2-dev.c:429 chrdev_open+0x237/0x6a0 fs/char_dev.c:414 do_dentry_open+0x735/0x1c40 fs/open.c:955 vfs_open+0x82/0x3f0 fs/open.c:1085 do_open fs/namei.c:3830 [inline] path_openat+0x1e88/0x2d80 fs/namei.c:3989 do_filp_open+0x20c/0x470 fs/namei.c:4016 do_sys_openat2+0x17a/0x1e0 fs/open.c:1427 do_sys_open fs/open.c:1442 [inline] __do_sys_openat fs/open.c:1458 [inline] __se_sys_openat fs/open.c:1453 [inline] __x64_sys_openat+0x175/0x210 fs/open.c:1453 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f4204d169a4 Code: 24 20 48 8d 44 24 30 48 89 44 24 28 64 8b 04 25 18 00 00 00 85 c0 75 2c 44 89 e2 48 89 ee bf 9c ff ff ff b8 01 01 00 00 0f 05 <48> 3d 00 f0 ff ff 76 60 48 8b 15 55 a4 0d 00 f7 d8 64 89 02 48 83 RSP: 002b:00007ffc161f8c00 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 00007ffc161f8e18 RCX: 00007f4204d169a4 RDX: 0000000000000000 RSI: 00007ffc161faf1d RDI: 00000000ffffff9c RBP: 00007ffc161faf1d R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ffc161f8e30 R14: 000055ff3524d670 R15: 00007f42051fba80 Allocated by task 5855: kasan_save_stack+0x33/0x60 mm/kasan/common.c:47 kasan_save_track+0x14/0x30 mm/kasan/common.c:68 poison_kmalloc_redzone mm/kasan/common.c:377 [inline] __kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:394 kmalloc_noprof include/linux/slab.h:901 [inline] kzalloc_noprof include/linux/slab.h:1037 [inline] em28xx_v4l2_init+0x114/0x4050 drivers/media/usb/em28xx/em28xx-video.c:2532 em28xx_init_extension+0x137/0x200 drivers/media/usb/em28xx/em28xx-core.c:1117 request_module_async+0x61/0x70 drivers/media/usb/em28xx/em28xx-cards.c:3457 process_one_work+0x9c5/0x1ba0 kernel/workqueue.c:3236 process_scheduled_works kernel/workqueue.c:3317 [inline] worker_thread+0x6c8/0xf00 kernel/workqueue.c:3398 kthread+0x3af/0x750 kernel/kthread.c:464 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 Freed by task 5855: kasan_save_stack+0x33/0x60 mm/kasan/common.c:47 kasan_save_track+0x14/0x30 mm/kasan/common.c:68 kasan_save_free_info+0x3b/0x60 mm/kasan/generic.c:576 poison_slab_object mm/kasan/common.c:247 [inline] __kasan_slab_free+0x51/0x70 mm/kasan/common.c:264 kasan_slab_free include/linux/kasan.h:233 [inline] slab_free_hook mm/slub.c:2353 [inline] slab_free mm/slub.c:4609 [inline] kfree+0x2c4/0x4d0 mm/slub.c:4757 em28xx_free_v4l2 drivers/media/usb/em28xx/em28xx-video.c:2118 [inline] kref_put include/linux/kref.h:65 [inline] em28xx_v4l2_init+0x22a4/0x4050 drivers/media/usb/em28xx/em28xx-video.c:2901 em28xx_init_extension+0x137/0x200 drivers/media/usb/em28xx/em28xx-core.c:1117 request_module_async+0x61/0x70 drivers/media/usb/em28xx/em28xx-cards.c:3457 process_one_work+0x9c5/0x1ba0 kernel/workqueue.c:3236 process_scheduled_works kernel/workqueue.c:3317 [inline] worker_thread+0x6c8/0xf00 kernel/workqueue.c:3398 kthread+0x3af/0x750 kernel/kthread.c:464 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 The buggy address belongs to the object at ffff88807e700000 which belongs to the cache kmalloc-8k of size 8192 The buggy address is located 1848 bytes inside of freed 8192-byte region [ffff88807e700000, ffff88807e702000) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x7e700 head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0 ksm flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff) page_type: f5(slab) raw: 00fff00000000040 ffff88801b042280 ffffea000087ce00 0000000000000003 raw: 0000000000000000 0000000000020002 00000000f5000000 0000000000000000 head: 00fff00000000040 ffff88801b042280 ffffea000087ce00 0000000000000003 head: 0000000000000000 0000000000020002 00000000f5000000 0000000000000000 head: 00fff00000000003 ffffea0001f9c001 ffffffffffffffff 0000000000000000 head: 0000000000000008 0000000000000000 00000000ffffffff 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 3, migratetype Unmovable, gfp_mask 0xd2040(__GFP_IO|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 5496, tgid 5496 (dhcpcd-run-hook), ts 31925844890, free_ts 31843543205 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x181/0x1b0 mm/page_alloc.c:1551 prep_new_page mm/page_alloc.c:1559 [inline] get_page_from_freelist+0xfce/0x2f80 mm/page_alloc.c:3477 __alloc_frozen_pages_noprof+0x221/0x2470 mm/page_alloc.c:4739 alloc_pages_mpol+0x1fc/0x540 mm/mempolicy.c:2270 alloc_slab_page mm/slub.c:2423 [inline] allocate_slab mm/slub.c:2587 [inline] new_slab+0x23d/0x330 mm/slub.c:2640 ___slab_alloc+0xc5d/0x1720 mm/slub.c:3826 __slab_alloc.constprop.0+0x56/0xb0 mm/slub.c:3916 __slab_alloc_node mm/slub.c:3991 [inline] slab_alloc_node mm/slub.c:4152 [inline] __kmalloc_cache_noprof+0xfa/0x410 mm/slub.c:4320 kmalloc_noprof include/linux/slab.h:901 [inline] kzalloc_noprof include/linux/slab.h:1037 [inline] tomoyo_print_bprm security/tomoyo/audit.c:26 [inline] tomoyo_init_log+0xcb3/0x2170 security/tomoyo/audit.c:264 tomoyo_supervisor+0x313/0x12f0 security/tomoyo/common.c:2119 tomoyo_audit_env_log security/tomoyo/environ.c:36 [inline] tomoyo_env_perm+0x193/0x210 security/tomoyo/environ.c:63 tomoyo_environ security/tomoyo/domain.c:672 [inline] tomoyo_find_next_domain+0xed4/0x20c0 security/tomoyo/domain.c:888 tomoyo_bprm_check_security security/tomoyo/tomoyo.c:102 [inline] tomoyo_bprm_check_security+0x12e/0x1d0 security/tomoyo/tomoyo.c:92 security_bprm_check+0x1b9/0x1e0 security/security.c:1302 search_binary_handler fs/exec.c:1765 [inline] exec_binprm fs/exec.c:1807 [inline] bprm_execve fs/exec.c:1859 [inline] bprm_execve+0x832/0x16d0 fs/exec.c:1835 do_execveat_common.isra.0+0x4a2/0x610 fs/exec.c:1966 page last free pid 5491 tgid 5491 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1127 [inline] free_frozen_pages+0x6db/0xfb0 mm/page_alloc.c:2660 __put_partials+0x14c/0x170 mm/slub.c:3153 qlink_free mm/kasan/quarantine.c:163 [inline] qlist_free_all+0x4e/0x120 mm/kasan/quarantine.c:179 kasan_quarantine_reduce+0x195/0x1e0 mm/kasan/quarantine.c:286 __kasan_slab_alloc+0x69/0x90 mm/kasan/common.c:329 kasan_slab_alloc include/linux/kasan.h:250 [inline] slab_post_alloc_hook mm/slub.c:4115 [inline] slab_alloc_node mm/slub.c:4164 [inline] __kmalloc_cache_noprof+0x243/0x410 mm/slub.c:4320 kmalloc_noprof include/linux/slab.h:901 [inline] tomoyo_print_header security/tomoyo/audit.c:156 [inline] tomoyo_init_log+0x195/0x2170 security/tomoyo/audit.c:255 tomoyo_supervisor+0x313/0x12f0 security/tomoyo/common.c:2119 tomoyo_audit_path_number_log security/tomoyo/file.c:235 [inline] tomoyo_path_number_perm+0x447/0x590 security/tomoyo/file.c:734 tomoyo_path_mknod+0x10d/0x190 security/tomoyo/tomoyo.c:252 security_path_mknod+0x161/0x310 security/security.c:1899 may_o_create fs/namei.c:3470 [inline] lookup_open.isra.0+0xc19/0x1580 fs/namei.c:3614 open_last_lookups fs/namei.c:3750 [inline] path_openat+0x904/0x2d80 fs/namei.c:3986 do_filp_open+0x20c/0x470 fs/namei.c:4016 do_sys_openat2+0x17a/0x1e0 fs/open.c:1427 do_sys_open fs/open.c:1442 [inline] __do_sys_openat fs/open.c:1458 [inline] __se_sys_openat fs/open.c:1453 [inline] __x64_sys_openat+0x175/0x210 fs/open.c:1453 Memory state around the buggy address: ffff88807e700600: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88807e700680: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff88807e700700: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88807e700780: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88807e700800: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================