================================================================== BUG: KASAN: use-after-free in io_queue_sqe fs/io_uring.c:2514 [inline] BUG: KASAN: use-after-free in io_queue_link_head+0x37a/0x5c0 fs/io_uring.c:2529 Read of size 8 at addr ffff8881ef2de950 by task syz-executor.3/1835 CPU: 0 PID: 1835 Comm: syz-executor.3 Not tainted 5.4.125-syzkaller-00121-g83ffd1a84016 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x1d8/0x24e lib/dump_stack.c:118 print_address_description+0x9b/0x650 mm/kasan/report.c:384 __kasan_report+0x182/0x260 mm/kasan/report.c:516 kasan_report+0x30/0x60 mm/kasan/common.c:641 io_queue_sqe fs/io_uring.c:2514 [inline] io_queue_link_head+0x37a/0x5c0 fs/io_uring.c:2529 io_ring_submit fs/io_uring.c:2945 [inline] __do_sys_io_uring_enter fs/io_uring.c:3853 [inline] __se_sys_io_uring_enter+0x702/0x1e50 fs/io_uring.c:3814 do_syscall_64+0xcb/0x1e0 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x4665d9 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 bc ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f4884336188 EFLAGS: 00000246 ORIG_RAX: 00000000000001aa RAX: ffffffffffffffda RBX: 000000000056bf80 RCX: 00000000004665d9 RDX: 0000000000000000 RSI: 00000000000002ff RDI: 0000000000000003 RBP: 00007f48843361d0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001 R13: 00007fff8f95e63f R14: 00007f4884336300 R15: 0000000000022000 Allocated by task 1835: save_stack mm/kasan/common.c:70 [inline] set_track mm/kasan/common.c:78 [inline] __kasan_kmalloc+0x137/0x1e0 mm/kasan/common.c:517 slab_post_alloc_hook mm/slab.h:584 [inline] kmem_cache_alloc_bulk+0x18e/0x290 mm/slub.c:3283 io_get_req+0x17a/0x590 fs/io_uring.c:652 io_submit_sqe+0x83/0xe80 fs/io_uring.c:2579 io_ring_submit fs/io_uring.c:2967 [inline] __do_sys_io_uring_enter fs/io_uring.c:3853 [inline] __se_sys_io_uring_enter+0x8b6/0x1e50 fs/io_uring.c:3814 do_syscall_64+0xcb/0x1e0 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x44/0xa9 Freed by task 1835: save_stack mm/kasan/common.c:70 [inline] set_track mm/kasan/common.c:78 [inline] kasan_set_free_info mm/kasan/common.c:333 [inline] __kasan_slab_free+0x18a/0x240 mm/kasan/common.c:475 slab_free_hook mm/slub.c:1454 [inline] slab_free_freelist_hook+0x7b/0x150 mm/slub.c:1492 slab_free mm/slub.c:3072 [inline] kmem_cache_free+0xb8/0x5f0 mm/slub.c:3088 io_queue_sqe fs/io_uring.c:2513 [inline] io_queue_link_head+0x364/0x5c0 fs/io_uring.c:2529 io_ring_submit fs/io_uring.c:2945 [inline] __do_sys_io_uring_enter fs/io_uring.c:3853 [inline] __se_sys_io_uring_enter+0x702/0x1e50 fs/io_uring.c:3814 do_syscall_64+0xcb/0x1e0 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x44/0xa9 The buggy address belongs to the object at ffff8881ef2de900 which belongs to the cache io_kiocb of size 264 The buggy address is located 80 bytes inside of 264-byte region [ffff8881ef2de900, ffff8881ef2dea08) The buggy address belongs to the page: page:ffffea0007bcb780 refcount:1 mapcount:0 mapping:ffff8881f0ee9b80 index:0x0 compound_mapcount: 0 flags: 0x8000000000010200(slab|head) raw: 8000000000010200 dead000000000100 dead000000000122 ffff8881f0ee9b80 raw: 0000000000000000 0000000000150015 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 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC) set_page_owner include/linux/page_owner.h:31 [inline] post_alloc_hook mm/page_alloc.c:2165 [inline] prep_new_page+0x19a/0x380 mm/page_alloc.c:2171 get_page_from_freelist+0x550/0x8b0 mm/page_alloc.c:3794 __alloc_pages_nodemask+0x3a2/0x880 mm/page_alloc.c:4855 alloc_slab_page+0x39/0x3e0 mm/slub.c:342 allocate_slab mm/slub.c:1675 [inline] new_slab+0x97/0x460 mm/slub.c:1741 new_slab_objects mm/slub.c:2498 [inline] ___slab_alloc+0x330/0x4c0 mm/slub.c:2659 kmem_cache_alloc_bulk+0xc7/0x290 mm/slub.c:3257 io_get_req+0x17a/0x590 fs/io_uring.c:652 io_submit_sqe+0x83/0xe80 fs/io_uring.c:2579 io_ring_submit fs/io_uring.c:2967 [inline] __do_sys_io_uring_enter fs/io_uring.c:3853 [inline] __se_sys_io_uring_enter+0x8b6/0x1e50 fs/io_uring.c:3814 do_syscall_64+0xcb/0x1e0 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_pages_ok+0xc60/0xd80 mm/page_alloc.c:1438 free_the_page mm/page_alloc.c:4917 [inline] __free_pages+0x8f/0x250 mm/page_alloc.c:4923 __free_slab+0x237/0x2f0 mm/slub.c:1766 free_slab mm/slub.c:1781 [inline] discard_slab mm/slub.c:1787 [inline] unfreeze_partials+0x14f/0x180 mm/slub.c:2279 put_cpu_partial+0xb5/0x150 mm/slub.c:2315 __slab_free mm/slub.c:2963 [inline] do_slab_free mm/slub.c:3060 [inline] ___cache_free+0x352/0x4e0 mm/slub.c:3079 qlist_free_all mm/kasan/quarantine.c:167 [inline] quarantine_reduce+0x17a/0x1e0 mm/kasan/quarantine.c:260 __kasan_kmalloc+0x43/0x1e0 mm/kasan/common.c:495 slab_post_alloc_hook mm/slab.h:584 [inline] slab_alloc_node mm/slub.c:2821 [inline] slab_alloc mm/slub.c:2829 [inline] kmem_cache_alloc+0x115/0x290 mm/slub.c:2834 kmem_cache_zalloc include/linux/slab.h:680 [inline] ext4_init_io_end+0x25/0xe0 fs/ext4/page-io.c:245 ext4_writepages+0x149f/0x3d40 fs/ext4/inode.c:2865 do_writepages+0x13a/0x280 mm/page-writeback.c:2344 __filemap_fdatawrite_range mm/filemap.c:421 [inline] file_write_and_wait_range+0x36c/0x470 mm/filemap.c:782 __generic_file_fsync+0x6e/0x190 fs/libfs.c:1006 ext4_sync_file+0x266/0xc70 fs/ext4/fsync.c:118 generic_write_sync include/linux/fs.h:2955 [inline] ext4_file_write_iter+0x9f5/0x10e0 fs/ext4/file.c:281 Memory state around the buggy address: ffff8881ef2de800: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8881ef2de880: fb fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff8881ef2de900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff8881ef2de980: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8881ef2dea00: fb fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ==================================================================