#syz dup: KASAN: use-after-free Write in irq_bypass_register_consumer
On Mon, May 21, 2018 at 7:25 PM, syzbot <syzbot+37364ced0d0b0fdf1...@syzkaller.appspotmail.com> wrote: > Hello, > > syzbot found the following crash on: > > HEAD commit: 0b449a441dac Merge tag 'dmaengine-fix-4.17-rc6' of git://g.. > git tree: upstream > console output: https://syzkaller.appspot.com/x/log.txt?x=16a44b37800000 > kernel config: https://syzkaller.appspot.com/x/.config?x=f3b4e30da84ec1ed > dashboard link: https://syzkaller.appspot.com/bug?extid=37364ced0d0b0fdf115c > compiler: gcc (GCC) 8.0.1 20180413 (experimental) > syzkaller repro:https://syzkaller.appspot.com/x/repro.syz?x=1120eb37800000 > C reproducer: https://syzkaller.appspot.com/x/repro.c?x=13f1227b800000 > > IMPORTANT: if you fix the bug, please add the following tag to the commit: > Reported-by: syzbot+37364ced0d0b0fdf1...@syzkaller.appspotmail.com > > random: sshd: uninitialized urandom read (32 bytes read) > random: sshd: uninitialized urandom read (32 bytes read) > random: sshd: uninitialized urandom read (32 bytes read) > IPVS: ftp: loaded support on port[0] = 21 > ================================================================== > BUG: KASAN: use-after-free in irq_bypass_unregister_consumer+0x3cd/0x4a0 > virt/lib/irqbypass.c:247 > Read of size 8 at addr ffff8801adf2a168 by task kworker/0:1/24 > > CPU: 0 PID: 24 Comm: kworker/0:1 Not tainted 4.17.0-rc5+ #59 > Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS > Google 01/01/2011 > Workqueue: kvm-irqfd-cleanup irqfd_shutdown > Call Trace: > __dump_stack lib/dump_stack.c:77 [inline] > dump_stack+0x1b9/0x294 lib/dump_stack.c:113 > print_address_description+0x6c/0x20b mm/kasan/report.c:256 > kasan_report_error mm/kasan/report.c:354 [inline] > kasan_report.cold.7+0x242/0x2fe mm/kasan/report.c:412 > __asan_report_load8_noabort+0x14/0x20 mm/kasan/report.c:433 > irq_bypass_unregister_consumer+0x3cd/0x4a0 virt/lib/irqbypass.c:247 > irqfd_shutdown+0x112/0x1a0 arch/x86/kvm/../../../virt/kvm/eventfd.c:145 > process_one_work+0xc1e/0x1b50 kernel/workqueue.c:2145 > worker_thread+0x1cc/0x1440 kernel/workqueue.c:2279 > kthread+0x345/0x410 kernel/kthread.c:240 > ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:412 > > Allocated by task 4534: > save_stack+0x43/0xd0 mm/kasan/kasan.c:448 > set_track mm/kasan/kasan.c:460 [inline] > kasan_kmalloc+0xc4/0xe0 mm/kasan/kasan.c:553 > kmem_cache_alloc_trace+0x152/0x780 mm/slab.c:3620 > kmalloc include/linux/slab.h:512 [inline] > kzalloc include/linux/slab.h:701 [inline] > kvm_irqfd_assign arch/x86/kvm/../../../virt/kvm/eventfd.c:296 [inline] > kvm_irqfd+0x187/0x1ec0 arch/x86/kvm/../../../virt/kvm/eventfd.c:572 > kvm_vm_ioctl+0xf84/0x1d90 arch/x86/kvm/../../../virt/kvm/kvm_main.c:2997 > vfs_ioctl fs/ioctl.c:46 [inline] > file_ioctl fs/ioctl.c:500 [inline] > do_vfs_ioctl+0x1cf/0x16a0 fs/ioctl.c:684 > ksys_ioctl+0xa9/0xd0 fs/ioctl.c:701 > __do_sys_ioctl fs/ioctl.c:708 [inline] > __se_sys_ioctl fs/ioctl.c:706 [inline] > __x64_sys_ioctl+0x73/0xb0 fs/ioctl.c:706 > do_syscall_64+0x1b1/0x800 arch/x86/entry/common.c:287 > entry_SYSCALL_64_after_hwframe+0x49/0xbe > > Freed by task 24: > save_stack+0x43/0xd0 mm/kasan/kasan.c:448 > set_track mm/kasan/kasan.c:460 [inline] > __kasan_slab_free+0x11a/0x170 mm/kasan/kasan.c:521 > kasan_slab_free+0xe/0x10 mm/kasan/kasan.c:528 > __cache_free mm/slab.c:3498 [inline] > kfree+0xd9/0x260 mm/slab.c:3813 > irqfd_shutdown+0x13a/0x1a0 arch/x86/kvm/../../../virt/kvm/eventfd.c:148 > process_one_work+0xc1e/0x1b50 kernel/workqueue.c:2145 > worker_thread+0x1cc/0x1440 kernel/workqueue.c:2279 > kthread+0x345/0x410 kernel/kthread.c:240 > ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:412 > > The buggy address belongs to the object at ffff8801adf2a000 > which belongs to the cache kmalloc-512 of size 512 > The buggy address is located 360 bytes inside of > 512-byte region [ffff8801adf2a000, ffff8801adf2a200) > The buggy address belongs to the page: > page:ffffea0006b7ca80 count:1 mapcount:0 mapping:ffff8801adf2a000 index:0x0 > flags: 0x2fffc0000000100(slab) > raw: 02fffc0000000100 ffff8801adf2a000 0000000000000000 0000000100000006 > raw: ffffea0007647a20 ffffea0006b45ba0 ffff8801da800940 0000000000000000 > page dumped because: kasan: bad access detected > > Memory state around the buggy address: > ffff8801adf2a000: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb > ffff8801adf2a080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >> >> ffff8801adf2a100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb > > ^ > ffff8801adf2a180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb > ffff8801adf2a200: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc > ================================================================== > > > --- > This bug 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 bug report. See: > https://goo.gl/tpsmEJ#bug-status-tracking for how to communicate with > syzbot. > syzbot can test patches for this bug, for details see: > https://goo.gl/tpsmEJ#testing-patches > > -- > You received this message because you are subscribed to the Google Groups > "syzkaller-bugs" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to syzkaller-bugs+unsubscr...@googlegroups.com. > To view this discussion on the web visit > https://groups.google.com/d/msgid/syzkaller-bugs/000000000000fd91d7056cba9422%40google.com. > For more options, visit https://groups.google.com/d/optout.
