On 21/09/2020 16:32, syzbot wrote: > Hello, > > syzbot found the following issue on: > > HEAD commit: 860461e4 Add linux-next specific files for 20200917 > git tree: linux-next > console output: https://syzkaller.appspot.com/x/log.txt?x=141fc5d9900000 > kernel config: https://syzkaller.appspot.com/x/.config?x=f2392812d6c63d5c > dashboard link: https://syzkaller.appspot.com/bug?extid=1d393803acac53c985a0 > compiler: gcc (GCC) 10.1.0-syz 20200507 > syz repro: https://syzkaller.appspot.com/x/repro.syz?x=16778b07900000 > C reproducer: https://syzkaller.appspot.com/x/repro.c?x=1216f8ad900000 > > IMPORTANT: if you fix the issue, please add the following tag to the commit: > Reported-by: syzbot+1d393803acac53c98...@syzkaller.appspotmail.com > > ================================================================== > BUG: KASAN: stack-out-of-bounds in memcpy include/linux/string.h:399 [inline] > BUG: KASAN: stack-out-of-bounds in read_extent_buffer+0x114/0x150 > fs/btrfs/extent_io.c:5674 > Write of size 8 at addr ffffc90000dd79f0 by task kworker/u4:1/21 > > CPU: 1 PID: 21 Comm: kworker/u4:1 Not tainted > 5.9.0-rc5-next-20200917-syzkaller #0 > Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS > Google 01/01/2011 > Workqueue: btrfs-endio-meta btrfs_work_helper > Call Trace: > __dump_stack lib/dump_stack.c:77 [inline] > dump_stack+0x198/0x1fb lib/dump_stack.c:118 > print_address_description.constprop.0.cold+0x5/0x497 mm/kasan/report.c:385 > __kasan_report mm/kasan/report.c:545 [inline] > kasan_report.cold+0x1f/0x37 mm/kasan/report.c:562 > check_memory_region_inline mm/kasan/generic.c:186 [inline] > check_memory_region+0x13d/0x180 mm/kasan/generic.c:192 > memcpy+0x39/0x60 mm/kasan/common.c:106 > memcpy include/linux/string.h:399 [inline] > read_extent_buffer+0x114/0x150 fs/btrfs/extent_io.c:5674 > btree_readpage_end_io_hook+0x7de/0x950 fs/btrfs/disk-io.c:641 > end_bio_extent_readpage+0x4de/0x10c0 fs/btrfs/extent_io.c:2854 > bio_endio+0x3d3/0x7a0 block/bio.c:1449 > end_workqueue_fn+0x114/0x170 fs/btrfs/disk-io.c:1696 > btrfs_work_helper+0x20a/0xd20 fs/btrfs/async-thread.c:318 > process_one_work+0x933/0x15a0 kernel/workqueue.c:2269 > worker_thread+0x64c/0x1120 kernel/workqueue.c:2415 > kthread+0x3af/0x4a0 kernel/kthread.c:292 > ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:296 > > > addr ffffc90000dd79f0 is located in stack of task kworker/u4:1/21 at offset > 48 in frame: > btree_readpage_end_io_hook+0x0/0x950 fs/btrfs/disk-io.c:201 > > this frame has 4 objects: > [48, 52) 'val' > [64, 80) 'fsid' > [96, 128) 'result' > [160, 192) 'found' > > Memory state around the buggy address: > ffffc90000dd7880: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 > ffffc90000dd7900: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 >> ffffc90000dd7980: 00 00 00 00 00 00 00 00 f1 f1 f1 f1 f1 f1 04 f2 > ^ > ffffc90000dd7a00: 00 00 f2 f2 00 00 00 00 f2 f2 f2 f2 00 00 00 00 > ffffc90000dd7a80: f3 f3 f3 f3 00 00 00 00 00 00 00 00 00 00 00 00 > ================================================================== > > > --- > This report is generated by a bot. It may contain errors. > See https://goo.gl/tpsmEJ for more information about syzbot. > syzbot engineers can be reached at syzkal...@googlegroups.com. > > syzbot will keep track of this issue. See: > https://goo.gl/tpsmEJ#status for how to communicate with syzbot. > syzbot can test patches for this issue, for details see: > https://goo.gl/tpsmEJ#testing-patches >
#syz test: git://github.com/kdave/btrfs-devel.git misc-5.9
