RBP: 00007f49dadd41d0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001 R13: 00007fffa95d1e9f R14: 00007f49dadd4300 R15: 0000000000022000 ================================================================== BUG: KASAN: use-after-free in io_queue_link_head+0x56f/0x680 fs/io_uring.c:2550 Read of size 8 at addr ffff8881e524de50 by task syz-executor.1/27018 CPU: 0 PID: 27018 Comm: syz-executor.1 Not tainted 5.4.210-syzkaller-00002-g35e910266d44 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/22/2022 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x18e/0x1d5 lib/dump_stack.c:118 print_address_description+0x8c/0x630 mm/kasan/report.c:384 __kasan_report+0xf6/0x130 mm/kasan/report.c:516 kasan_report+0x30/0x60 mm/kasan/common.c:653 io_queue_link_head+0x56f/0x680 fs/io_uring.c:2550 io_ring_submit fs/io_uring.c:2979 [inline] __do_sys_io_uring_enter fs/io_uring.c:3861 [inline] __se_sys_io_uring_enter+0xb4a/0x1d70 fs/io_uring.c:3822 do_syscall_64+0xcb/0x1c0 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x7f49dbc605a9 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 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 b8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f49dadd4168 EFLAGS: 00000246 ORIG_RAX: 00000000000001aa RAX: ffffffffffffffda RBX: 00007f49dbd80f80 RCX: 00007f49dbc605a9 RDX: 0000000000000000 RSI: 000000000000076d RDI: 0000000000000003 RBP: 00007f49dadd41d0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001 R13: 00007fffa95d1e9f R14: 00007f49dadd4300 R15: 0000000000022000 Allocated by task 27018: save_stack mm/kasan/common.c:70 [inline] set_track mm/kasan/common.c:78 [inline] __kasan_kmalloc+0x131/0x1e0 mm/kasan/common.c:529 slab_post_alloc_hook mm/slab.h:584 [inline] kmem_cache_alloc_bulk+0x16f/0x270 mm/slub.c:3291 io_get_req+0x17a/0x590 fs/io_uring.c:668 io_submit_sqe+0x83/0xe80 fs/io_uring.c:2587 io_ring_submit fs/io_uring.c:2975 [inline] __do_sys_io_uring_enter fs/io_uring.c:3861 [inline] __se_sys_io_uring_enter+0x804/0x1d70 fs/io_uring.c:3822 do_syscall_64+0xcb/0x1c0 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x44/0xa9 Freed by task 27018: save_stack mm/kasan/common.c:70 [inline] set_track mm/kasan/common.c:78 [inline] kasan_set_free_info mm/kasan/common.c:345 [inline] __kasan_slab_free+0x178/0x240 mm/kasan/common.c:487 slab_free_hook mm/slub.c:1455 [inline] slab_free_freelist_hook+0x80/0x150 mm/slub.c:1494 slab_free mm/slub.c:3080 [inline] kmem_cache_free+0xa9/0x1d0 mm/slub.c:3096 io_queue_link_head+0x2b7/0x680 fs/io_uring.c:2548 io_ring_submit fs/io_uring.c:2979 [inline] __do_sys_io_uring_enter fs/io_uring.c:3861 [inline] __se_sys_io_uring_enter+0xb4a/0x1d70 fs/io_uring.c:3822 do_syscall_64+0xcb/0x1c0 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x44/0xa9 The buggy address belongs to the object at ffff8881e524de00 which belongs to the cache io_kiocb of size 264 The buggy address is located 80 bytes inside of 264-byte region [ffff8881e524de00, ffff8881e524df08) The buggy address belongs to the page: page:ffffea0007949300 refcount:1 mapcount:0 mapping:ffff8881f55de500 index:0x0 compound_mapcount: 0 flags: 0x8000000000010200(slab|head) raw: 8000000000010200 dead000000000100 dead000000000122 ffff8881f55de500 raw: 0000000000000000 0000000080150015 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 1, migratetype Unmovable, gfp_mask 0x1d20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC|__GFP_HARDWALL) set_page_owner include/linux/page_owner.h:31 [inline] post_alloc_hook mm/page_alloc.c:2165 [inline] prep_new_page+0x194/0x380 mm/page_alloc.c:2171 get_page_from_freelist+0x524/0x560 mm/page_alloc.c:3794 __alloc_pages_nodemask+0x2ab/0x6f0 mm/page_alloc.c:4857 alloc_slab_page+0x39/0x3e0 mm/slub.c:343 allocate_slab mm/slub.c:1683 [inline] new_slab+0x97/0x450 mm/slub.c:1749 new_slab_objects mm/slub.c:2505 [inline] ___slab_alloc+0x320/0x4a0 mm/slub.c:2667 kmem_cache_alloc_bulk+0xc6/0x270 mm/slub.c:3265 io_get_req+0x17a/0x590 fs/io_uring.c:668 io_submit_sqe+0x83/0xe80 fs/io_uring.c:2587 io_ring_submit fs/io_uring.c:2975 [inline] __do_sys_io_uring_enter fs/io_uring.c:3861 [inline] __se_sys_io_uring_enter+0x804/0x1d70 fs/io_uring.c:3822 do_syscall_64+0xcb/0x1c0 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x44/0xa9 page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1176 [inline] free_pcp_prepare+0x1a4/0x290 mm/page_alloc.c:1233 free_unref_page_prepare mm/page_alloc.c:3085 [inline] free_unref_page_list+0xc0/0x610 mm/page_alloc.c:3154 release_pages+0xa23/0xa50 mm/swap.c:842 tlb_batch_pages_flush mm/mmu_gather.c:49 [inline] tlb_flush_mmu_free mm/mmu_gather.c:184 [inline] tlb_flush_mmu+0x77f/0x910 mm/mmu_gather.c:191 tlb_finish_mmu+0xcb/0x200 mm/mmu_gather.c:272 exit_mmap+0x2a6/0x4f0 mm/mmap.c:3168 __mmput+0x34/0x240 kernel/fork.c:1090 exit_mm kernel/exit.c:489 [inline] do_exit+0xb40/0x2b40 kernel/exit.c:799 do_group_exit+0x136/0x300 kernel/exit.c:910 get_signal+0xd99/0x13f0 kernel/signal.c:2735 do_signal+0x41/0x10a0 arch/x86/kernel/signal.c:809 exit_to_usermode_loop+0xdd/0x1d0 arch/x86/entry/common.c:159 prepare_exit_to_usermode+0x17c/0x1d0 arch/x86/entry/common.c:194 entry_SYSCALL_64_after_hwframe+0x44/0xa9 Memory state around the buggy address: ffff8881e524dd00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8881e524dd80: fb fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff8881e524de00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff8881e524de80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8881e524df00: fb fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ==================================================================