On Mon, Oct 30, 2017 at 10:12 PM, syzbot <bot+7ad82526b98c64c90062275162dacfa48c20dbd3@xxxxxxxxxxxxxxxxxxxxxxxxx> wrote: > Hello, > > syzkaller hit the following crash on > cd4175b11685b11c40e31a03e05084cc212b0649 > git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/master > compiler: gcc (GCC) 7.1.1 20170620 > .config is attached > Raw console output is attached. > > syzkaller reproducer is attached. See https://goo.gl/kgGztJ > for information about syzkaller reproducers This also happens on more recent commits, including upstream 19e12196da601f7b80b5639adbcecf60fae13389 (Oct 29). > BUG: KASAN: use-after-free in __list_add include/linux/list.h:63 [inline] > BUG: KASAN: use-after-free in list_add include/linux/list.h:78 [inline] > BUG: KASAN: use-after-free in irq_bypass_register_consumer+0x4b4/0x500 > virt/lib/irqbypass.c:217 > Write of size 8 at addr ffff8801c994a240 by task syz-executor0/4607 > > CPU: 0 PID: 4607 Comm: syz-executor0 Not tainted 4.14.0-rc1+ #8 > Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS > Google 01/01/2011 > Call Trace: > __dump_stack lib/dump_stack.c:16 [inline] > dump_stack+0x194/0x257 lib/dump_stack.c:52 > print_address_description+0x73/0x250 mm/kasan/report.c:252 > kasan_report_error mm/kasan/report.c:351 [inline] > kasan_report+0x24e/0x340 mm/kasan/report.c:409 > __asan_report_store8_noabort+0x17/0x20 mm/kasan/report.c:435 > __list_add include/linux/list.h:63 [inline] > list_add include/linux/list.h:78 [inline] > irq_bypass_register_consumer+0x4b4/0x500 virt/lib/irqbypass.c:217 > kvm_irqfd_assign arch/x86/kvm/../../../virt/kvm/eventfd.c:417 [inline] > kvm_irqfd+0x137a/0x1d50 arch/x86/kvm/../../../virt/kvm/eventfd.c:572 > kvm_vm_ioctl+0x1079/0x1c40 arch/x86/kvm/../../../virt/kvm/kvm_main.c:2991 > kvm_vm_compat_ioctl+0x2ed/0x3e0 > arch/x86/kvm/../../../virt/kvm/kvm_main.c:3135 > C_SYSC_ioctl fs/compat_ioctl.c:1593 [inline] > compat_SyS_ioctl+0x1da/0x3300 fs/compat_ioctl.c:1540 > do_syscall_32_irqs_on arch/x86/entry/common.c:329 [inline] > do_fast_syscall_32+0x3f2/0xeed arch/x86/entry/common.c:391 > entry_SYSENTER_compat+0x51/0x60 arch/x86/entry/entry_64_compat.S:124 > RIP: 0023:0xf7f5ac79 > RSP: 002b:00000000f7f5605c EFLAGS: 00000296 ORIG_RAX: 0000000000000036 > RAX: ffffffffffffffda RBX: 0000000000000009 RCX: 000000004020ae76 > RDX: 0000000020025fe0 RSI: 0000000000000000 RDI: 0000000000000000 > RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 > R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 > R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 > > Allocated by task 4607: > save_stack_trace+0x16/0x20 arch/x86/kernel/stacktrace.c:59 > save_stack+0x43/0xd0 mm/kasan/kasan.c:447 > set_track mm/kasan/kasan.c:459 [inline] > kasan_kmalloc+0xad/0xe0 mm/kasan/kasan.c:551 > kmem_cache_alloc_trace+0x136/0x750 mm/slab.c:3627 > kmalloc include/linux/slab.h:493 [inline] > kzalloc include/linux/slab.h:666 [inline] > kvm_irqfd_assign arch/x86/kvm/../../../virt/kvm/eventfd.c:296 [inline] > kvm_irqfd+0x16c/0x1d50 arch/x86/kvm/../../../virt/kvm/eventfd.c:572 > kvm_vm_ioctl+0x1079/0x1c40 arch/x86/kvm/../../../virt/kvm/kvm_main.c:2991 > kvm_vm_compat_ioctl+0x2ed/0x3e0 > arch/x86/kvm/../../../virt/kvm/kvm_main.c:3135 > C_SYSC_ioctl fs/compat_ioctl.c:1593 [inline] > compat_SyS_ioctl+0x1da/0x3300 fs/compat_ioctl.c:1540 > do_syscall_32_irqs_on arch/x86/entry/common.c:329 [inline] > do_fast_syscall_32+0x3f2/0xeed arch/x86/entry/common.c:391 > entry_SYSENTER_compat+0x51/0x60 arch/x86/entry/entry_64_compat.S:124 > > Freed by task 23: > save_stack_trace+0x16/0x20 arch/x86/kernel/stacktrace.c:59 > save_stack+0x43/0xd0 mm/kasan/kasan.c:447 > set_track mm/kasan/kasan.c:459 [inline] > kasan_slab_free+0x71/0xc0 mm/kasan/kasan.c:524 > __cache_free mm/slab.c:3503 [inline] > kfree+0xca/0x250 mm/slab.c:3820 > irqfd_shutdown+0x13c/0x1a0 arch/x86/kvm/../../../virt/kvm/eventfd.c:148 > process_one_work+0xbfa/0x1bd0 kernel/workqueue.c:2119 > worker_thread+0x223/0x1860 kernel/workqueue.c:2253 > kthread+0x39c/0x470 kernel/kthread.c:231 > ret_from_fork+0x2a/0x40 arch/x86/entry/entry_64.S:431 > > The buggy address belongs to the object at ffff8801c994a0c0 > which belongs to the cache kmalloc-512 of size 512 > The buggy address is located 384 bytes inside of > 512-byte region [ffff8801c994a0c0, ffff8801c994a2c0) > The buggy address belongs to the page: > page:ffffea0007265280 count:1 mapcount:0 mapping:ffff8801c994a0c0 > index:0xffff8801c994ad40 > flags: 0x200000000000100(slab) > raw: 0200000000000100 ffff8801c994a0c0 ffff8801c994ad40 0000000100000001 > raw: ffffea0007265320 ffffea00072630e0 ffff8801dac00940 0000000000000000 > page dumped because: kasan: bad access detected > > Memory state around the buggy address: > ffff8801c994a100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb > ffff8801c994a180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >> >> ffff8801c994a200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb > > ^ > ffff8801c994a280: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc > ffff8801c994a300: fc fc fc fc fc fc fc fc fb fb fb fb fb fb fb fb > ================================================================== > > > --- > This bug is generated by a dumb bot. It may contain errors. > See https://goo.gl/tpsmEJ for details. > Direct all questions to syzkaller@xxxxxxxxxxxxxxxx. > > syzbot will keep track of this bug report. > Once a fix for this bug is committed, please reply to this email with: > #syz fix: exact-commit-title > To mark this as a duplicate of another syzbot report, please reply with: > #syz dup: exact-subject-of-another-report > If it's a one-off invalid bug report, please reply with: > #syz invalid > Note: if the crash happens again, it will cause creation of a new bug > report. > > -- > 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+unsubscribe@xxxxxxxxxxxxxxxx. > To view this discussion on the web visit > https://groups.google.com/d/msgid/syzkaller-bugs/001a1143e716efd3a9055cc8696b%40google.com. > For more options, visit https://groups.google.com/d/optout.
