================================================================== BUG: KASAN: slab-use-after-free in __mutex_lock_common kernel/locking/mutex.c:582 [inline] BUG: KASAN: slab-use-after-free in __mutex_lock+0xfc/0xc80 kernel/locking/mutex.c:747 Read of size 8 at addr ffff88802d6f5c60 by task syz-executor/5789 CPU: 1 PID: 5789 Comm: syz-executor Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/07/2026 Call Trace: dump_stack_lvl+0x18c/0x250 lib/dump_stack.c:106 print_address_description mm/kasan/report.c:364 [inline] print_report+0xa8/0x210 mm/kasan/report.c:468 kasan_report+0x117/0x150 mm/kasan/report.c:581 __mutex_lock_common kernel/locking/mutex.c:582 [inline] __mutex_lock+0xfc/0xc80 kernel/locking/mutex.c:747 ep_open+0x4e/0x270 drivers/usb/gadget/legacy/inode.c:819 do_dentry_open+0x880/0x14b0 fs/open.c:929 do_open fs/namei.c:3695 [inline] path_openat+0x284f/0x3270 fs/namei.c:3856 do_filp_open+0x1f2/0x430 fs/namei.c:3883 do_sys_openat2+0x134/0x1d0 fs/open.c:1422 do_sys_open fs/open.c:1437 [inline] __do_sys_openat fs/open.c:1453 [inline] __se_sys_openat fs/open.c:1448 [inline] __x64_sys_openat+0x139/0x160 fs/open.c:1448 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7fb3a795fd8e Code: 08 0f 85 a5 a8 ff ff 49 89 fb 48 89 f0 48 89 d7 48 89 ce 4c 89 c2 4d 89 ca 4c 8b 44 24 08 4c 8b 4c 24 10 4c 89 5c 24 08 0f 05 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 80 00 00 00 00 48 83 ec 08 RSP: 002b:00007ffe0f650838 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 000055559448e500 RCX: 00007fb3a795fd8e RDX: 0000000000000000 RSI: 00007ffe0f6509a0 RDI: ffffffffffffff9c RBP: 00007ffe0f6509a0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffe0f651a90 R13: 00007fb3a7a35f63 R14: 000055559448e4e8 R15: 0000000000000006 Allocated by task 8121: kasan_save_stack mm/kasan/common.c:46 [inline] kasan_set_track+0x4e/0x70 mm/kasan/common.c:53 ____kasan_kmalloc mm/kasan/common.c:375 [inline] __kasan_kmalloc+0x8f/0xa0 mm/kasan/common.c:384 kmalloc include/linux/slab.h:600 [inline] kzalloc include/linux/slab.h:721 [inline] activate_ep_files drivers/usb/gadget/legacy/inode.c:1592 [inline] gadgetfs_bind+0x25f/0x830 drivers/usb/gadget/legacy/inode.c:1683 gadget_bind_driver+0x2b3/0x770 drivers/usb/gadget/udc/core.c:1661 call_driver_probe drivers/base/dd.c:-1 [inline] really_probe+0x24a/0xae0 drivers/base/dd.c:717 __driver_probe_device+0x1f5/0x390 drivers/base/dd.c:879 driver_probe_device+0x4f/0x420 drivers/base/dd.c:909 __driver_attach+0x444/0x6d0 drivers/base/dd.c:1295 bus_for_each_dev+0x235/0x2b0 drivers/base/bus.c:370 bus_add_driver+0x340/0x630 drivers/base/bus.c:723 driver_register+0x23a/0x310 drivers/base/driver.c:246 usb_gadget_register_driver_owner+0xf9/0x270 drivers/usb/gadget/udc/core.c:1740 dev_config+0xe49/0x1260 drivers/usb/gadget/legacy/inode.c:1874 vfs_write+0x299/0x9a0 fs/read_write.c:582 ksys_write+0x151/0x260 fs/read_write.c:637 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 Freed by task 1198: kasan_save_stack mm/kasan/common.c:46 [inline] kasan_set_track+0x4e/0x70 mm/kasan/common.c:53 kasan_save_free_info+0x28/0x40 mm/kasan/generic.c:522 ____kasan_slab_free+0x126/0x1f0 mm/kasan/common.c:237 kasan_slab_free include/linux/kasan.h:164 [inline] slab_free_hook mm/slub.c:1833 [inline] slab_free_freelist_hook+0x154/0x240 mm/slub.c:1859 slab_free mm/slub.c:3853 [inline] __kmem_cache_free+0xba/0x1f0 mm/slub.c:3866 destroy_ep_files+0x282/0x330 drivers/usb/gadget/legacy/inode.c:1570 gadgetfs_unbind+0x109/0x2b0 drivers/usb/gadget/legacy/inode.c:1646 gadget_unbind_driver+0x1bf/0x3e0 drivers/usb/gadget/udc/core.c:1712 device_remove drivers/base/dd.c:626 [inline] __device_release_driver drivers/base/dd.c:1351 [inline] device_release_driver_internal+0x408/0x6f0 drivers/base/dd.c:1374 driver_detach+0x1f3/0x2d0 drivers/base/dd.c:1437 bus_remove_driver+0x221/0x2f0 drivers/base/bus.c:792 usb_gadget_unregister_driver+0x4e/0x70 drivers/usb/gadget/udc/core.c:1772 dev_release+0x86/0x200 drivers/usb/gadget/legacy/inode.c:1194 __fput+0x221/0x940 fs/file_table.c:418 delayed_fput+0x58/0x80 fs/file_table.c:441 process_one_work kernel/workqueue.c:2657 [inline] process_scheduled_works+0xa60/0x1600 kernel/workqueue.c:2734 worker_thread+0xa5e/0xfe0 kernel/workqueue.c:2815 kthread+0x2fa/0x390 kernel/kthread.c:388 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293 The buggy address belongs to the object at ffff88802d6f5c00 which belongs to the cache kmalloc-512 of size 512 The buggy address is located 96 bytes inside of freed 512-byte region [ffff88802d6f5c00, ffff88802d6f5e00) The buggy address belongs to the physical page: page:ffffea0000b5bd00 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x2d6f4 head:ffffea0000b5bd00 order:2 entire_mapcount:0 nr_pages_mapped:0 pincount:0 anon flags: 0xfff00000000840(slab|head|node=0|zone=1|lastcpupid=0x7ff) page_type: 0xffffffff() raw: 00fff00000000840 ffff888018c41c80 0000000000000000 dead000000000001 raw: 0000000000000000 0000000000100010 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 2, migratetype Unmovable, gfp_mask 0x1d20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC|__GFP_HARDWALL), pid 5789, tgid 5789 (syz-executor), ts 97522801843, free_ts 96830749369 set_page_owner include/linux/page_owner.h:31 [inline] post_alloc_hook+0x1c1/0x200 mm/page_alloc.c:1582 prep_new_page mm/page_alloc.c:1589 [inline] get_page_from_freelist+0x2181/0x22a0 mm/page_alloc.c:3221 __alloc_pages+0x1f0/0x460 mm/page_alloc.c:4501 alloc_slab_page+0x5d/0x180 mm/slub.c:1903 allocate_slab mm/slub.c:2050 [inline] new_slab+0x87/0x2d0 mm/slub.c:2103 ___slab_alloc+0xc5c/0x12f0 mm/slub.c:3275 __slab_alloc mm/slub.c:3361 [inline] __slab_alloc_node mm/slub.c:3414 [inline] slab_alloc_node mm/slub.c:3508 [inline] __kmem_cache_alloc_node+0x122/0x260 mm/slub.c:3557 kmalloc_trace+0x2a/0xe0 mm/slab_common.c:1098 kmalloc include/linux/slab.h:600 [inline] kzalloc include/linux/slab.h:721 [inline] kernfs_fop_open+0x3d2/0xc60 fs/kernfs/file.c:690 do_dentry_open+0x880/0x14b0 fs/open.c:929 do_open fs/namei.c:3695 [inline] path_openat+0x284f/0x3270 fs/namei.c:3856 do_filp_open+0x1f2/0x430 fs/namei.c:3883 do_sys_openat2+0x134/0x1d0 fs/open.c:1422 do_sys_open fs/open.c:1437 [inline] __do_sys_openat fs/open.c:1453 [inline] __se_sys_openat fs/open.c:1448 [inline] __x64_sys_openat+0x139/0x160 fs/open.c:1448 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1182 [inline] free_unref_page_prepare+0x7d7/0x8f0 mm/page_alloc.c:2366 free_unref_page+0x32/0x2e0 mm/page_alloc.c:2459 __slab_free+0x35a/0x400 mm/slub.c:3759 qlink_free mm/kasan/quarantine.c:166 [inline] qlist_free_all+0x75/0xd0 mm/kasan/quarantine.c:185 kasan_quarantine_reduce+0x143/0x160 mm/kasan/quarantine.c:292 __kasan_slab_alloc+0x22/0x80 mm/kasan/common.c:306 kasan_slab_alloc include/linux/kasan.h:188 [inline] slab_post_alloc_hook+0x6a/0x4d0 mm/slab.h:770 slab_alloc_node mm/slub.c:3518 [inline] __kmem_cache_alloc_node+0x197/0x260 mm/slub.c:3557 __do_kmalloc_node mm/slab_common.c:1006 [inline] __kmalloc+0xa7/0x240 mm/slab_common.c:1020 kmalloc_array include/linux/slab.h:637 [inline] kcalloc include/linux/slab.h:668 [inline] iter_file_splice_write+0x1a4/0xcf0 fs/splice.c:676 do_splice_from fs/splice.c:933 [inline] direct_splice_actor+0xe8/0x130 fs/splice.c:1142 splice_direct_to_actor+0x30b/0x8e0 fs/splice.c:1088 do_splice_direct+0x1d5/0x2f0 fs/splice.c:1194 do_sendfile+0x52b/0xe80 fs/read_write.c:1254 __do_sys_sendfile64 fs/read_write.c:1322 [inline] __se_sys_sendfile64+0x145/0x1a0 fs/read_write.c:1308 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:76 Memory state around the buggy address: ffff88802d6f5b00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88802d6f5b80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff88802d6f5c00: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88802d6f5c80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88802d6f5d00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================