================================================================== BUG: KASAN: use-after-free in blkdev_bio_end_io+0x3e3/0x4b0 fs/block_dev.c:301 Read of size 1 at addr ffff8880a581f914 by task ksoftirqd/0/9 CPU: 0 PID: 9 Comm: ksoftirqd/0 Not tainted 5.3.0-rc4 #100 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+0x172/0x1f0 lib/dump_stack.c:113 print_address_description.cold+0xd4/0x306 mm/kasan/report.c:351 __kasan_report.cold+0x1b/0x36 mm/kasan/report.c:482 kasan_report+0x12/0x17 mm/kasan/common.c:612 __asan_report_load1_noabort+0x14/0x20 mm/kasan/generic_report.c:129 blkdev_bio_end_io+0x3e3/0x4b0 fs/block_dev.c:301 bio_endio+0x611/0xaf0 block/bio.c:1830 req_bio_endio block/blk-core.c:239 [inline] blk_update_request+0x32e/0xc10 block/blk-core.c:1424 blk_mq_end_request+0x5b/0x560 block/blk-mq.c:557 end_cmd drivers/block/null_blk_main.c:622 [inline] end_cmd+0x111/0x310 drivers/block/null_blk_main.c:616 null_complete_rq+0x19/0x20 drivers/block/null_blk_main.c:649 blk_done_softirq+0x2fe/0x4d0 block/blk-softirq.c:37 __do_softirq+0x262/0x98c kernel/softirq.c:292 run_ksoftirqd kernel/softirq.c:603 [inline] run_ksoftirqd+0x8e/0x110 kernel/softirq.c:595 smpboot_thread_fn+0x6a3/0xa40 kernel/smpboot.c:165 kthread+0x361/0x430 kernel/kthread.c:255 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352 Allocated by task 20042: save_stack+0x23/0x90 mm/kasan/common.c:69 set_track mm/kasan/common.c:77 [inline] __kasan_kmalloc mm/kasan/common.c:487 [inline] __kasan_kmalloc.constprop.0+0xcf/0xe0 mm/kasan/common.c:460 kasan_slab_alloc+0xf/0x20 mm/kasan/common.c:495 slab_post_alloc_hook mm/slab.h:520 [inline] slab_alloc mm/slab.c:3319 [inline] kmem_cache_alloc+0x121/0x710 mm/slab.c:3483 mempool_alloc_slab+0x47/0x60 mm/mempool.c:513 mempool_alloc+0x169/0x380 mm/mempool.c:393 bio_alloc_bioset+0x3b9/0x680 block/bio.c:477 __blkdev_direct_IO fs/block_dev.c:363 [inline] blkdev_direct_IO+0x397/0x1680 fs/block_dev.c:515 generic_file_direct_write+0x20a/0x4a0 mm/filemap.c:3230 __generic_file_write_iter+0x2ee/0x630 mm/filemap.c:3413 blkdev_write_iter fs/block_dev.c:2026 [inline] blkdev_write_iter+0x23a/0x440 fs/block_dev.c:2003 call_write_iter include/linux/fs.h:1870 [inline] aio_write+0x2f2/0x540 fs/aio.c:1583 __io_submit_one fs/aio.c:1815 [inline] io_submit_one+0x1012/0x2ef0 fs/aio.c:1862 __do_sys_io_submit fs/aio.c:1921 [inline] __se_sys_io_submit fs/aio.c:1891 [inline] __x64_sys_io_submit+0x1bd/0x570 fs/aio.c:1891 do_syscall_64+0xfd/0x6a0 arch/x86/entry/common.c:296 entry_SYSCALL_64_after_hwframe+0x49/0xbe Freed by task 9: save_stack+0x23/0x90 mm/kasan/common.c:69 set_track mm/kasan/common.c:77 [inline] __kasan_slab_free+0x102/0x150 mm/kasan/common.c:449 kasan_slab_free+0xe/0x10 mm/kasan/common.c:457 __cache_free mm/slab.c:3425 [inline] kmem_cache_free+0x86/0x320 mm/slab.c:3693 mempool_free_slab+0x1e/0x30 mm/mempool.c:520 mempool_free+0xeb/0x370 mm/mempool.c:502 bio_free+0x267/0x420 block/bio.c:255 bio_put+0xda/0x110 block/bio.c:549 blkdev_bio_end_io+0x338/0x4b0 fs/block_dev.c:333 bio_endio+0x611/0xaf0 block/bio.c:1830 req_bio_endio block/blk-core.c:239 [inline] blk_update_request+0x32e/0xc10 block/blk-core.c:1424 blk_mq_end_request+0x5b/0x560 block/blk-mq.c:557 end_cmd drivers/block/null_blk_main.c:622 [inline] end_cmd+0x111/0x310 drivers/block/null_blk_main.c:616 null_complete_rq+0x19/0x20 drivers/block/null_blk_main.c:649 blk_done_softirq+0x2fe/0x4d0 block/blk-softirq.c:37 __do_softirq+0x262/0x98c kernel/softirq.c:292 The buggy address belongs to the object at ffff8880a581f900 which belongs to the cache bio-1 of size 216 The buggy address is located 20 bytes inside of 216-byte region [ffff8880a581f900, ffff8880a581f9d8) The buggy address belongs to the page: page:ffffea00029607c0 refcount:1 mapcount:0 mapping:ffff8880a6b54a80 index:0x0 flags: 0x1fffc0000000200(slab) raw: 01fffc0000000200 ffff8880a5fe4848 ffffea00025fefc8 ffff8880a6b54a80 raw: 0000000000000000 ffff8880a581f040 000000010000000c 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff8880a581f800: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff8880a581f880: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff8880a581f900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff8880a581f980: fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc fc ffff8880a581fa00: fc fc fc fc fc fc fc fc fb fb fb fb fb fb fb fb ==================================================================