================================================================== BUG: KASAN: use-after-free in __lock_acquire+0x3eb0/0x56c0 kernel/locking/lockdep.c:4899 Read of size 8 at addr ffff888076fae328 by task kworker/0:0/6 CPU: 0 PID: 6 Comm: kworker/0:0 Not tainted 5.18.0-rc3-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: events io_fallback_req_func Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106 print_address_description.constprop.0.cold+0xeb/0x495 mm/kasan/report.c:313 print_report mm/kasan/report.c:429 [inline] kasan_report.cold+0xf4/0x1c6 mm/kasan/report.c:491 __lock_acquire+0x3eb0/0x56c0 kernel/locking/lockdep.c:4899 lock_acquire kernel/locking/lockdep.c:5641 [inline] lock_acquire+0x1ab/0x510 kernel/locking/lockdep.c:5606 __raw_spin_lock_irq include/linux/spinlock_api_smp.h:119 [inline] _raw_spin_lock_irq+0x32/0x50 kernel/locking/spinlock.c:170 spin_lock_irq include/linux/spinlock.h:374 [inline] io_poll_remove_entry fs/io_uring.c:5794 [inline] io_poll_remove_entries.part.0+0x15f/0x7e0 fs/io_uring.c:5827 io_poll_remove_entries fs/io_uring.c:5807 [inline] io_apoll_task_func+0xe6/0x270 fs/io_uring.c:5928 io_fallback_req_func+0xf9/0x1ae fs/io_uring.c:1497 process_one_work+0x996/0x1610 kernel/workqueue.c:2289 worker_thread+0x665/0x1080 kernel/workqueue.c:2436 kthread+0x2e9/0x3a0 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:298 Allocated by task 3786: kasan_save_stack+0x1e/0x40 mm/kasan/common.c:38 kasan_set_track mm/kasan/common.c:45 [inline] set_alloc_info mm/kasan/common.c:436 [inline] ____kasan_kmalloc mm/kasan/common.c:515 [inline] ____kasan_kmalloc mm/kasan/common.c:474 [inline] __kasan_kmalloc+0xa9/0xd0 mm/kasan/common.c:524 io_ring_ctx_alloc fs/io_uring.c:1511 [inline] io_uring_create fs/io_uring.c:11146 [inline] io_uring_setup.cold+0x133/0x257d fs/io_uring.c:11253 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae Freed by task 3654: kasan_save_stack+0x1e/0x40 mm/kasan/common.c:38 kasan_set_track+0x21/0x30 mm/kasan/common.c:45 kasan_set_free_info+0x20/0x30 mm/kasan/generic.c:370 ____kasan_slab_free mm/kasan/common.c:366 [inline] ____kasan_slab_free+0x166/0x1a0 mm/kasan/common.c:328 kasan_slab_free include/linux/kasan.h:200 [inline] slab_free_hook mm/slub.c:1728 [inline] slab_free_freelist_hook+0x8b/0x1c0 mm/slub.c:1754 slab_free mm/slub.c:3510 [inline] kfree+0xd6/0x4d0 mm/slub.c:4552 io_ring_ctx_free fs/io_uring.c:9967 [inline] io_ring_exit_work+0xf57/0xf9d fs/io_uring.c:10110 process_one_work+0x996/0x1610 kernel/workqueue.c:2289 worker_thread+0x665/0x1080 kernel/workqueue.c:2436 kthread+0x2e9/0x3a0 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:298 Last potentially related work creation: kasan_save_stack+0x1e/0x40 mm/kasan/common.c:38 __kasan_record_aux_stack+0xbe/0xd0 mm/kasan/generic.c:348 insert_work+0x48/0x350 kernel/workqueue.c:1358 __queue_work+0x62e/0x1140 kernel/workqueue.c:1517 queue_work_on+0xee/0x110 kernel/workqueue.c:1545 queue_work include/linux/workqueue.h:502 [inline] io_ring_ctx_wait_and_kill+0x2f2/0x327 fs/io_uring.c:10163 io_uring_release+0x42/0x46 fs/io_uring.c:10171 __fput+0x277/0x9d0 fs/file_table.c:317 task_work_run+0xdd/0x1a0 kernel/task_work.c:164 exit_task_work include/linux/task_work.h:37 [inline] do_exit+0xaff/0x2a00 kernel/exit.c:795 io_sq_thread.cold+0x1b9/0x1c3 fs/io_uring.c:8056 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:298 The buggy address belongs to the object at ffff888076fae000 which belongs to the cache kmalloc-2k of size 2048 The buggy address is located 808 bytes inside of 2048-byte region [ffff888076fae000, ffff888076fae800) The buggy address belongs to the physical page: page:ffffea0001dbea00 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x76fa8 head:ffffea0001dbea00 order:3 compound_mapcount:0 compound_pincount:0 flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000010200 0000000000000000 dead000000000122 ffff888010c42000 raw: 0000000000000000 0000000000080008 00000001ffffffff 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 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 3776, tgid 3776 (syz-executor165), ts 561696685616, free_ts 561644426549 prep_new_page mm/page_alloc.c:2441 [inline] get_page_from_freelist+0xba2/0x3e00 mm/page_alloc.c:4182 __alloc_pages+0x1b2/0x500 mm/page_alloc.c:5408 alloc_pages+0x1aa/0x310 mm/mempolicy.c:2272 alloc_slab_page mm/slub.c:1799 [inline] allocate_slab+0x26c/0x3c0 mm/slub.c:1944 new_slab mm/slub.c:2004 [inline] ___slab_alloc+0x8df/0xf20 mm/slub.c:3005 __slab_alloc.constprop.0+0x4d/0xa0 mm/slub.c:3092 slab_alloc_node mm/slub.c:3183 [inline] slab_alloc mm/slub.c:3225 [inline] __kmalloc+0x318/0x350 mm/slub.c:4410 io_ring_ctx_alloc fs/io_uring.c:1511 [inline] io_uring_create fs/io_uring.c:11146 [inline] io_uring_setup.cold+0x133/0x257d fs/io_uring.c:11253 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1356 [inline] free_pcp_prepare+0x549/0xd20 mm/page_alloc.c:1406 free_unref_page_prepare mm/page_alloc.c:3328 [inline] free_unref_page+0x19/0x6a0 mm/page_alloc.c:3423 __unfreeze_partials+0x17c/0x1a0 mm/slub.c:2523 qlink_free mm/kasan/quarantine.c:157 [inline] qlist_free_all+0x6a/0x170 mm/kasan/quarantine.c:176 kasan_quarantine_reduce+0x180/0x200 mm/kasan/quarantine.c:283 __kasan_slab_alloc+0xa2/0xc0 mm/kasan/common.c:446 kasan_slab_alloc include/linux/kasan.h:224 [inline] slab_post_alloc_hook mm/slab.h:749 [inline] slab_alloc_node mm/slub.c:3217 [inline] kmem_cache_alloc_node+0x255/0x3f0 mm/slub.c:3267 alloc_task_struct_node kernel/fork.c:172 [inline] dup_task_struct kernel/fork.c:970 [inline] copy_process+0x5c4/0x6fe0 kernel/fork.c:2068 kernel_clone+0xe7/0xab0 kernel/fork.c:2639 __do_sys_clone+0xc8/0x110 kernel/fork.c:2756 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae Memory state around the buggy address: ffff888076fae200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888076fae280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff888076fae300: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888076fae380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888076fae400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================