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BUG: KASAN: use-after-free in d_inode include/linux/dcache.h:516 [inline]
BUG: KASAN: use-after-free in relay_switch_subbuf+0x8cc/0x940 kernel/relay.c:761
Read of size 8 at addr ffff88808d8f67b8 by task syz-executor.1/970

CPU: 1 PID: 970 Comm: syz-executor.1 Not tainted 4.19.211-syzkaller #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+0x1fc/0x2ef lib/dump_stack.c:118
 print_address_description.cold+0x54/0x219 mm/kasan/report.c:256
 kasan_report_error.cold+0x8a/0x1b9 mm/kasan/report.c:354
 kasan_report mm/kasan/report.c:412 [inline]
 __asan_report_load8_noabort+0x88/0x90 mm/kasan/report.c:433
 d_inode include/linux/dcache.h:516 [inline]
 relay_switch_subbuf+0x8cc/0x940 kernel/relay.c:761
 relay_reserve include/linux/relay.h:261 [inline]
 trace_note+0x5eb/0x750 kernel/trace/blktrace.c:96
 trace_note_tsk kernel/trace/blktrace.c:127 [inline]
 __blk_add_trace+0xb86/0xe20 kernel/trace/blktrace.c:267
 blk_add_trace_plug+0xfe/0x240 kernel/trace/blktrace.c:1000
 trace_block_plug include/trace/events/block.h:456 [inline]
 blk_mq_make_request+0x14b7/0x1c00 block/blk-mq.c:1902
 generic_make_request+0x613/0xdf0 block/blk-core.c:2467
 submit_bio+0xb1/0x430 block/blk-core.c:2576
 dio_bio_submit fs/direct-io.c:481 [inline]
 dio_send_cur_page fs/direct-io.c:815 [inline]
 submit_page_section fs/direct-io.c:883 [inline]
 do_direct_IO fs/direct-io.c:1097 [inline]
 do_blockdev_direct_IO fs/direct-io.c:1333 [inline]
 __blockdev_direct_IO+0x81ba/0xef40 fs/direct-io.c:1419
 ext4_direct_IO_write fs/ext4/inode.c:3777 [inline]
 ext4_direct_IO+0xae4/0x1c50 fs/ext4/inode.c:3915
 generic_file_direct_write+0x208/0x4a0 mm/filemap.c:3073
 __generic_file_write_iter+0x2d0/0x610 mm/filemap.c:3252
 ext4_file_write_iter+0x2fe/0xf20 fs/ext4/file.c:272
 call_write_iter include/linux/fs.h:1821 [inline]
 aio_write+0x37f/0x5c0 fs/aio.c:1574
 __io_submit_one fs/aio.c:1858 [inline]
 io_submit_one+0xecd/0x20c0 fs/aio.c:1909
 __do_sys_io_submit fs/aio.c:1953 [inline]
 __se_sys_io_submit+0x11b/0x4a0 fs/aio.c:1924
 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x7fc0d9708059
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:00007fc0d807d168 EFLAGS: 00000246 ORIG_RAX: 00000000000000d1
RAX: ffffffffffffffda RBX: 00007fc0d981af60 RCX: 00007fc0d9708059
RDX: 0000000020000540 RSI: 000000000000003b RDI: 00007fc0d97f6000
RBP: 00007fc0d976208d R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ffc0916d56f R14: 00007fc0d807d300 R15: 0000000000022000

Allocated by task 8098:
 kmem_cache_alloc+0x122/0x370 mm/slab.c:3559
 __d_alloc+0x2b/0xa10 fs/dcache.c:1612
 d_alloc_pseudo+0x19/0x70 fs/dcache.c:1743
 alloc_file_pseudo+0xc6/0x250 fs/file_table.c:224
 sock_alloc_file+0x48/0x180 net/socket.c:406
 sock_map_fd net/socket.c:429 [inline]
 __sys_socket+0x13d/0x200 net/socket.c:1462
 __do_sys_socket net/socket.c:1467 [inline]
 __se_sys_socket net/socket.c:1465 [inline]
 __x64_sys_socket+0x6f/0xb0 net/socket.c:1465
 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293
 entry_SYSCALL_64_after_hwframe+0x49/0xbe

Freed by task 8098:
 __cache_free mm/slab.c:3503 [inline]
 kmem_cache_free+0x7f/0x260 mm/slab.c:3765
 __d_free fs/dcache.c:257 [inline]
 dentry_free+0xda/0x150 fs/dcache.c:348
 __dentry_kill+0x4c6/0x640 fs/dcache.c:580
 dentry_kill+0xc4/0x510 fs/dcache.c:685
 dput+0x55f/0x640 fs/dcache.c:846
 __fput+0x415/0x890 fs/file_table.c:291
 task_work_run+0x148/0x1c0 kernel/task_work.c:113
 tracehook_notify_resume include/linux/tracehook.h:193 [inline]
 exit_to_usermode_loop+0x251/0x2a0 arch/x86/entry/common.c:167
 prepare_exit_to_usermode arch/x86/entry/common.c:198 [inline]
 syscall_return_slowpath arch/x86/entry/common.c:271 [inline]
 do_syscall_64+0x538/0x620 arch/x86/entry/common.c:296
 entry_SYSCALL_64_after_hwframe+0x49/0xbe

The buggy address belongs to the object at ffff88808d8f6760
 which belongs to the cache dentry of size 288
The buggy address is located 88 bytes inside of
 288-byte region [ffff88808d8f6760, ffff88808d8f6880)
The buggy address belongs to the page:
page:ffffea0002363d80 count:1 mapcount:0 mapping:ffff88813be45200 index:0x0
flags: 0xfff00000000100(slab)
raw: 00fff00000000100 ffffea00023fe988 ffffea0002361fc8 ffff88813be45200
raw: 0000000000000000 ffff88808d8f6080 000000010000000b 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff88808d8f6680: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff88808d8f6700: 00 00 00 00 fc fc fc fc fc fc fc fc fb fb fb fb
>ffff88808d8f6780: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                        ^
 ffff88808d8f6800: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88808d8f6880: fc fc fc fc fc fc fc fc 00 00 00 00 00 00 00 00
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