================================================================== BUG: KASAN: use-after-free in wq_stack_extract io_uring/slist.h:126 [inline] BUG: KASAN: use-after-free in io_alloc_req io_uring/io_uring.h:356 [inline] BUG: KASAN: use-after-free in io_req_caches_free+0x18d/0x1e6 io_uring/io_uring.c:2735 Read of size 8 at addr ffff8880263397f8 by task kworker/u4:9/5456 CPU: 0 PID: 5456 Comm: kworker/u4:9 Not tainted 6.2.0-rc3-next-20230112-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/26/2022 Workqueue: events_unbound io_ring_exit_work Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xd1/0x138 lib/dump_stack.c:106 print_address_description mm/kasan/report.c:306 [inline] print_report+0x15e/0x45d mm/kasan/report.c:417 kasan_report+0xc0/0xf0 mm/kasan/report.c:517 wq_stack_extract io_uring/slist.h:126 [inline] io_alloc_req io_uring/io_uring.h:356 [inline] io_req_caches_free+0x18d/0x1e6 io_uring/io_uring.c:2735 io_ring_exit_work+0x2e7/0xc80 io_uring/io_uring.c:2967 process_one_work+0x9bf/0x1750 kernel/workqueue.c:2293 worker_thread+0x669/0x1090 kernel/workqueue.c:2440 kthread+0x2e8/0x3a0 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308 Allocated by task 6234: kasan_save_stack+0x22/0x40 mm/kasan/common.c:45 kasan_set_track+0x25/0x30 mm/kasan/common.c:52 __kasan_slab_alloc+0x7f/0x90 mm/kasan/common.c:325 kasan_slab_alloc include/linux/kasan.h:186 [inline] slab_post_alloc_hook mm/slab.h:769 [inline] kmem_cache_alloc_bulk+0x3aa/0x730 mm/slub.c:4033 __io_alloc_req_refill+0xcc/0x40b io_uring/io_uring.c:1062 io_alloc_req_refill io_uring/io_uring.h:348 [inline] io_submit_sqes.cold+0x7c/0xc2 io_uring/io_uring.c:2407 __do_sys_io_uring_enter+0x9e4/0x2c10 io_uring/io_uring.c:3429 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x39/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd Freed by task 5456: kasan_save_stack+0x22/0x40 mm/kasan/common.c:45 kasan_set_track+0x25/0x30 mm/kasan/common.c:52 kasan_save_free_info+0x2e/0x40 mm/kasan/generic.c:518 ____kasan_slab_free mm/kasan/common.c:236 [inline] ____kasan_slab_free+0x160/0x1c0 mm/kasan/common.c:200 kasan_slab_free include/linux/kasan.h:162 [inline] slab_free_hook mm/slub.c:1781 [inline] slab_free_freelist_hook+0x8b/0x1c0 mm/slub.c:1807 slab_free mm/slub.c:3787 [inline] kmem_cache_free+0xec/0x4e0 mm/slub.c:3809 io_req_caches_free+0x1a9/0x1e6 io_uring/io_uring.c:2737 io_ring_exit_work+0x2e7/0xc80 io_uring/io_uring.c:2967 process_one_work+0x9bf/0x1750 kernel/workqueue.c:2293 worker_thread+0x669/0x1090 kernel/workqueue.c:2440 kthread+0x2e8/0x3a0 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308 The buggy address belongs to the object at ffff888026339780 which belongs to the cache io_kiocb of size 216 The buggy address is located 120 bytes inside of 216-byte region [ffff888026339780, ffff888026339858) The buggy address belongs to the physical page: page:ffffea000098ce40 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x26339 memcg:ffff888026d5d401 flags: 0xfff00000000200(slab|node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000000200 ffff8881461f8a00 ffffea0001c18840 0000000000000006 raw: 0000000000000000 00000000000c000c 00000001ffffffff ffff888026d5d401 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 0, migratetype Unmovable, gfp_mask 0x112cc0(GFP_USER|__GFP_NOWARN|__GFP_NORETRY), pid 5955, tgid 5954 (syz-executor.2), ts 292007873728, free_ts 283379272604 prep_new_page mm/page_alloc.c:2549 [inline] get_page_from_freelist+0x11bb/0x2d50 mm/page_alloc.c:4324 __alloc_pages+0x1cb/0x5c0 mm/page_alloc.c:5590 alloc_pages+0x1aa/0x270 mm/mempolicy.c:2281 alloc_slab_page mm/slub.c:1851 [inline] allocate_slab+0x25f/0x350 mm/slub.c:1998 new_slab mm/slub.c:2051 [inline] ___slab_alloc+0xa91/0x1400 mm/slub.c:3193 __kmem_cache_alloc_bulk mm/slub.c:3951 [inline] kmem_cache_alloc_bulk+0x23d/0x730 mm/slub.c:4026 __io_alloc_req_refill+0xcc/0x40b io_uring/io_uring.c:1062 io_alloc_req_refill io_uring/io_uring.h:348 [inline] io_submit_sqes.cold+0x7c/0xc2 io_uring/io_uring.c:2407 __do_sys_io_uring_enter+0x9e4/0x2c10 io_uring/io_uring.c:3429 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x39/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1451 [inline] free_pcp_prepare+0x4d0/0x910 mm/page_alloc.c:1501 free_unref_page_prepare mm/page_alloc.c:3387 [inline] free_unref_page+0x1d/0x490 mm/page_alloc.c:3482 relay_destroy_buf+0x121/0x3e0 kernel/relay.c:201 relay_remove_buf kernel/relay.c:221 [inline] kref_put include/linux/kref.h:65 [inline] relay_close_buf+0x153/0x1b0 kernel/relay.c:430 relay_close kernel/relay.c:766 [inline] relay_close+0x3a4/0x590 kernel/relay.c:752 blk_trace_free+0x37/0x190 kernel/trace/blktrace.c:316 blk_trace_cleanup kernel/trace/blktrace.c:384 [inline] __blk_trace_remove+0x83/0x190 kernel/trace/blktrace.c:397 blk_trace_ioctl+0x24c/0x290 kernel/trace/blktrace.c:760 blkdev_common_ioctl+0x11c7/0x1ba0 block/ioctl.c:536 blkdev_ioctl+0x2c6/0x800 block/ioctl.c:610 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:870 [inline] __se_sys_ioctl fs/ioctl.c:856 [inline] __x64_sys_ioctl+0x197/0x210 fs/ioctl.c:856 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x39/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd Memory state around the buggy address: ffff888026339680: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff888026339700: 00 00 00 fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff888026339780: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888026339800: fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc fc ffff888026339880: fc fc fc fc fc fc fc fc 00 00 00 00 00 00 00 00 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