================================================================== BUG: KASAN: slab-use-after-free in __mutex_lock_common kernel/locking/mutex.c:728 [inline] BUG: KASAN: slab-use-after-free in __mutex_lock+0x7d9/0x15a0 kernel/locking/mutex.c:821 Read of size 8 at addr ffff888065ce6450 by task syz.4.2398/14314 CPU: 1 UID: 0 PID: 14314 Comm: syz.4.2398 Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/15/2026 Call Trace: dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120 print_address_description+0x55/0x1e0 mm/kasan/report.c:378 print_report+0x58/0x70 mm/kasan/report.c:482 kasan_report+0x117/0x150 mm/kasan/report.c:595 __mutex_lock_common kernel/locking/mutex.c:728 [inline] __mutex_lock+0x7d9/0x15a0 kernel/locking/mutex.c:821 ep_open+0x4e/0x270 drivers/usb/gadget/legacy/inode.c:953 do_dentry_open+0x80e/0x1360 fs/open.c:1000 vfs_open_consume+0x4a/0x350 fs/open.c:1131 do_open fs/namei.c:4851 [inline] path_openat+0x16fc/0x20f0 fs/namei.c:5016 do_file_open+0x23e/0x4a0 fs/namei.c:5045 do_sys_openat2+0x115/0x200 fs/open.c:1442 do_sys_open fs/open.c:1448 [inline] __do_sys_openat fs/open.c:1788 [inline] __se_sys_openat fs/open.c:1783 [inline] __x64_sys_openat+0x138/0x170 fs/open.c:1783 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline] do_syscall_64+0x166/0x520 arch/x86/entry/syscall_64.c:84 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f2a4959f559 Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 e8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f2a4a486028 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 00007f2a49826090 RCX: 00007f2a4959f559 RDX: 0000000000024000 RSI: 0000200000000200 RDI: ffffffffffffff9c RBP: 00007f2a49636b50 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000060 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f2a49826128 R14: 00007f2a49826090 R15: 00007ffe3d80adc8 Allocated by task 14312: kasan_save_stack mm/kasan/common.c:57 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:78 poison_kmalloc_redzone mm/kasan/common.c:409 [inline] __kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:426 kasan_kmalloc include/linux/kasan.h:263 [inline] __kmalloc_cache_noprof+0x31c/0x600 mm/slub.c:5680 _kmalloc_noprof include/linux/slab.h:991 [inline] _kzalloc_noprof include/linux/slab.h:1312 [inline] activate_ep_files drivers/usb/gadget/legacy/inode.c:1732 [inline] gadgetfs_bind+0x2ef/0xb10 drivers/usb/gadget/legacy/inode.c:1825 gadget_bind_driver+0x2ca/0x9e0 drivers/usb/gadget/udc/core.c:1663 call_driver_probe drivers/base/dd.c:-1 [inline] really_probe+0x254/0xae0 drivers/base/dd.c:707 __driver_probe_device+0x1e8/0x360 drivers/base/dd.c:869 driver_probe_device+0x4f/0x240 drivers/base/dd.c:899 __driver_attach+0x34e/0x630 drivers/base/dd.c:1300 bus_for_each_dev+0x23b/0x2c0 drivers/base/bus.c:383 bus_add_driver+0x38f/0x6e0 drivers/base/bus.c:782 driver_register+0x23a/0x320 drivers/base/driver.c:174 usb_gadget_register_driver_owner+0xf9/0x270 drivers/usb/gadget/udc/core.c:1753 dev_config+0xe3c/0x12a0 drivers/usb/gadget/legacy/inode.c:2015 vfs_write+0x296/0xba0 fs/read_write.c:685 ksys_write+0x150/0x270 fs/read_write.c:1036 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline] do_syscall_64+0x166/0x520 arch/x86/entry/syscall_64.c:84 entry_SYSCALL_64_after_hwframe+0x77/0x7f Freed by task 14312: kasan_save_stack mm/kasan/common.c:57 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:78 kasan_save_free_info+0x40/0x50 mm/kasan/generic.c:584 poison_slab_object mm/kasan/common.c:264 [inline] __kasan_slab_free+0x5c/0x80 mm/kasan/common.c:296 kasan_slab_free include/linux/kasan.h:235 [inline] slab_free_hook mm/slub.c:2780 [inline] slab_free mm/slub.c:6630 [inline] kfree+0x1c5/0x650 mm/slub.c:6923 destroy_ep_files+0x2a3/0x330 drivers/usb/gadget/legacy/inode.c:1713 activate_ep_files drivers/usb/gadget/legacy/inode.c:1766 [inline] gadgetfs_bind+0x9aa/0xb10 drivers/usb/gadget/legacy/inode.c:1825 gadget_bind_driver+0x2ca/0x9e0 drivers/usb/gadget/udc/core.c:1663 call_driver_probe drivers/base/dd.c:-1 [inline] really_probe+0x254/0xae0 drivers/base/dd.c:707 __driver_probe_device+0x1e8/0x360 drivers/base/dd.c:869 driver_probe_device+0x4f/0x240 drivers/base/dd.c:899 __driver_attach+0x34e/0x630 drivers/base/dd.c:1300 bus_for_each_dev+0x23b/0x2c0 drivers/base/bus.c:383 bus_add_driver+0x38f/0x6e0 drivers/base/bus.c:782 driver_register+0x23a/0x320 drivers/base/driver.c:174 usb_gadget_register_driver_owner+0xf9/0x270 drivers/usb/gadget/udc/core.c:1753 dev_config+0xe3c/0x12a0 drivers/usb/gadget/legacy/inode.c:2015 vfs_write+0x296/0xba0 fs/read_write.c:685 ksys_write+0x150/0x270 fs/read_write.c:1036 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline] do_syscall_64+0x166/0x520 arch/x86/entry/syscall_64.c:84 entry_SYSCALL_64_after_hwframe+0x77/0x7f The buggy address belongs to the object at ffff888065ce6400 which belongs to the cache kmalloc-512 of size 512 The buggy address is located 80 bytes inside of freed 512-byte region [ffff888065ce6400, ffff888065ce6600) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x65ce4 head: order:2 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0 flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff) page_type: f5(slab) raw: 00fff00000000040 ffff88813ff37c80 dead000000000100 dead000000000122 raw: 0000000000000000 0000000000100010 00000000f5000000 0000000000000000 head: 00fff00000000040 ffff88813ff37c80 dead000000000100 dead000000000122 head: 0000000000000000 0000000000100010 00000000f5000000 0000000000000000 head: 00fff00000000002 ffffffffffffff01 00000000ffffffff 00000000ffffffff head: ffffffffffffffff 0000000000000000 00000000ffffffff 0000000000000004 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 2, migratetype Unmovable, gfp_mask 0xd2820(GFP_ATOMIC|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 13, tgid 13 (kworker/u8:0), ts 96054688775 set_page_owner include/linux/page_owner.h:33 [inline] post_alloc_hook+0x1f9/0x250 mm/page_alloc.c:1859 prep_new_page mm/page_alloc.c:1867 [inline] get_page_from_freelist+0x220f/0x2280 mm/page_alloc.c:3938 __alloc_frozen_pages_noprof+0x1fe/0x410 mm/page_alloc.c:5447 alloc_slab_page mm/slub.c:3384 [inline] allocate_slab+0x7d/0x5e0 mm/slub.c:3499 new_slab mm/slub.c:3550 [inline] refill_objects+0x2d5/0x350 mm/slub.c:7539 refill_sheaf mm/slub.c:2917 [inline] __pcs_replace_empty_main+0x2c8/0x6c0 mm/slub.c:4811 alloc_from_pcs mm/slub.c:4887 [inline] slab_alloc_node mm/slub.c:5021 [inline] __kmalloc_cache_noprof+0x396/0x600 mm/slub.c:5676 _kmalloc_noprof include/linux/slab.h:991 [inline] batadv_forw_packet_alloc+0x178/0x370 net/batman-adv/send.c:511 batadv_iv_ogm_aggregate_new net/batman-adv/bat_iv_ogm.c:648 [inline] batadv_iv_ogm_queue_add+0x8b8/0xd90 net/batman-adv/bat_iv_ogm.c:769 batadv_iv_ogm_schedule_buff net/batman-adv/bat_iv_ogm.c:973 [inline] batadv_iv_ogm_schedule+0xafb/0xfc0 net/batman-adv/bat_iv_ogm.c:1011 batadv_iv_send_outstanding_bat_ogm_packet+0x622/0x740 net/batman-adv/bat_iv_ogm.c:1924 process_one_work kernel/workqueue.c:3495 [inline] process_scheduled_works+0xc3d/0x1630 kernel/workqueue.c:3578 worker_thread+0xa47/0xfb0 kernel/workqueue.c:3659 kthread+0x38b/0x480 kernel/kthread.c:436 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 page last free pid 5628 tgid 5628 ts 86873687440 stack trace: reset_page_owner include/linux/page_owner.h:26 [inline] __free_pages_prepare mm/page_alloc.c:1403 [inline] free_unref_folios+0xdc6/0x14e0 mm/page_alloc.c:3017 folios_put_refs+0x9e9/0xb30 mm/folio.c:1039 free_pages_and_swap_cache+0x2ba/0x490 mm/swap_state.c:654 __tlb_batch_free_encoded_pages mm/mmu_gather.c:138 [inline] tlb_batch_pages_flush mm/mmu_gather.c:151 [inline] tlb_flush_mmu_free mm/mmu_gather.c:397 [inline] tlb_flush_mmu+0x6d3/0xa30 mm/mmu_gather.c:404 tlb_finish_mmu+0xf4/0x220 mm/mmu_gather.c:529 unmap_region+0x2a5/0x330 mm/vma.c:516 vms_clear_ptes mm/vma.c:1389 [inline] vms_complete_munmap_vmas+0x442/0xc10 mm/vma.c:1431 do_vmi_align_munmap+0x3b7/0x4b0 mm/vma.c:1690 do_vmi_munmap+0x252/0x2d0 mm/vma.c:1738 __vm_munmap+0x240/0x420 mm/vma.c:3588 __do_sys_munmap mm/mmap.c:1094 [inline] __se_sys_munmap mm/mmap.c:1091 [inline] __x64_sys_munmap+0x60/0x70 mm/mmap.c:1091 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline] do_syscall_64+0x166/0x520 arch/x86/entry/syscall_64.c:84 entry_SYSCALL_64_after_hwframe+0x77/0x7f Memory state around the buggy address: ffff888065ce6300: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff888065ce6380: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff888065ce6400: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888065ce6480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888065ce6500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================