On Sat, Mar 4, 2017 at 5:24 PM, Dmitry Vyukov <dvyukov@xxxxxxxxxx> wrote: > On Fri, Jan 27, 2017 at 10:26 PM, Dmitry Vyukov <dvyukov@xxxxxxxxxx> wrote: >> Hello, >> >> The following program triggers use-after-free in irq_bypass_register_consumer: >> https://bit.googleplex.com/raw/5875575541465088/5629499534213120/ >> >> BUG: KASAN: use-after-free in irq_bypass_register_consumer+0x48c/0x4c0 >> virt/lib/irqbypass.c:198 at addr ffff88006b74b438 >> Read of size 8 by task a.out/24723 >> CPU: 1 PID: 24723 Comm: a.out Not tainted 4.10.0-rc5+ #201 >> Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011 >> Call Trace: >> __dump_stack lib/dump_stack.c:15 [inline] >> dump_stack+0x2ee/0x3ef lib/dump_stack.c:51 >> kasan_object_err+0x1c/0x70 mm/kasan/report.c:165 >> print_address_description mm/kasan/report.c:203 [inline] >> kasan_report_error+0x17b/0x430 mm/kasan/report.c:287 >> kasan_report mm/kasan/report.c:307 [inline] >> __asan_report_load8_noabort+0x3e/0x40 mm/kasan/report.c:328 >> irq_bypass_register_consumer+0x48c/0x4c0 virt/lib/irqbypass.c:198 >> kvm_irqfd_assign arch/x86/kvm/../../../virt/kvm/eventfd.c:417 [inline] >> kvm_irqfd+0x130e/0x1e30 arch/x86/kvm/../../../virt/kvm/eventfd.c:578 >> kvm_vm_ioctl+0x107a/0x1d10 arch/x86/kvm/../../../virt/kvm/kvm_main.c:3007 >> vfs_ioctl fs/ioctl.c:43 [inline] >> do_vfs_ioctl+0x1bf/0x1790 fs/ioctl.c:683 >> SYSC_ioctl fs/ioctl.c:698 [inline] >> SyS_ioctl+0x8f/0xc0 fs/ioctl.c:689 >> entry_SYSCALL_64_fastpath+0x1f/0xc2 >> RIP: 0033:0x4402b9 >> RSP: 002b:00007f7f07514d98 EFLAGS: 00000297 ORIG_RAX: 0000000000000010 >> RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00000000004402b9 >> RDX: 0000000020ae3000 RSI: 000000004020ae76 RDI: 0000000000000007 >> RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 >> R10: 0000000000000000 R11: 0000000000000297 R12: 0000000000000000 >> R13: 0000000000000000 R14: 00007f7f075159c0 R15: 00007f7f07515700 >> Object at ffff88006b74b2c0, in cache kmalloc-512 size: 512 >> Allocated: >> PID = 24723 >> [<ffffffff812b1506>] save_stack_trace+0x16/0x20 arch/x86/kernel/stacktrace.c:57 >> [<ffffffff81a0cdd3>] save_stack+0x43/0xd0 mm/kasan/kasan.c:502 >> [<ffffffff81a0d09a>] set_track mm/kasan/kasan.c:514 [inline] >> [<ffffffff81a0d09a>] kasan_kmalloc+0xaa/0xd0 mm/kasan/kasan.c:605 >> [<ffffffff81a098eb>] kmem_cache_alloc_trace+0x10b/0x670 mm/slab.c:3629 >> [<ffffffff8108b95f>] kmalloc include/linux/slab.h:490 [inline] >> [<ffffffff8108b95f>] kzalloc include/linux/slab.h:636 [inline] >> [<ffffffff8108b95f>] kvm_irqfd_assign >> arch/x86/kvm/../../../virt/kvm/eventfd.c:296 [inline] >> [<ffffffff8108b95f>] kvm_irqfd+0x16f/0x1e30 >> arch/x86/kvm/../../../virt/kvm/eventfd.c:578 >> [<ffffffff81081b4a>] kvm_vm_ioctl+0x107a/0x1d10 >> arch/x86/kvm/../../../virt/kvm/kvm_main.c:3007 >> [<ffffffff81aa41cf>] vfs_ioctl fs/ioctl.c:43 [inline] >> [<ffffffff81aa41cf>] do_vfs_ioctl+0x1bf/0x1790 fs/ioctl.c:683 >> [<ffffffff81aa582f>] SYSC_ioctl fs/ioctl.c:698 [inline] >> [<ffffffff81aa582f>] SyS_ioctl+0x8f/0xc0 fs/ioctl.c:689 >> [<ffffffff841c9c81>] entry_SYSCALL_64_fastpath+0x1f/0xc2 >> Freed: >> PID = 1556 >> [<ffffffff812b1506>] save_stack_trace+0x16/0x20 arch/x86/kernel/stacktrace.c:57 >> [<ffffffff81a0cdd3>] save_stack+0x43/0xd0 mm/kasan/kasan.c:502 >> [<ffffffff81a0d70f>] set_track mm/kasan/kasan.c:514 [inline] >> [<ffffffff81a0d70f>] kasan_slab_free+0x6f/0xb0 mm/kasan/kasan.c:578 >> [<ffffffff81a0b5c3>] __cache_free mm/slab.c:3505 [inline] >> [<ffffffff81a0b5c3>] kfree+0xd3/0x250 mm/slab.c:3822 >> [<ffffffff8108b4f0>] irqfd_shutdown+0x150/0x1c0 >> arch/x86/kvm/../../../virt/kvm/eventfd.c:148 >> [<ffffffff814b4920>] process_one_work+0xbd0/0x1c10 kernel/workqueue.c:2098 >> [<ffffffff814b5b83>] worker_thread+0x223/0x1990 kernel/workqueue.c:2232 >> [<ffffffff814ce546>] kthread+0x326/0x3f0 kernel/kthread.c:227 >> [<ffffffff841c9ef1>] ret_from_fork+0x31/0x40 arch/x86/entry/entry_64.S:430 >> >> On commit fd694aaa46c7ed811b72eb47d5eb11ce7ab3f7f1. > > > Still happens on commit 0710f3ff91ecc4a715db6e4d0690472b13c4dac6: > > BUG: KASAN: use-after-free in irq_bypass_register_consumer+0x4cb/0x4e0 > virt/lib/irqbypass.c:198 at addr ffff88006777ddf8 > Read of size 8 by task a.out/15766 > CPU: 2 PID: 15766 Comm: a.out Not tainted 4.10.0+ #285 > Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011 > Call Trace: > __dump_stack lib/dump_stack.c:16 [inline] > dump_stack+0x2fb/0x3fd lib/dump_stack.c:52 > kasan_object_err+0x1c/0x70 mm/kasan/report.c:166 > print_address_description mm/kasan/report.c:204 [inline] > kasan_report_error mm/kasan/report.c:288 [inline] > kasan_report.part.2+0x1b0/0x460 mm/kasan/report.c:310 > kasan_report mm/kasan/report.c:331 [inline] > __asan_report_load8_noabort+0x29/0x30 mm/kasan/report.c:331 > irq_bypass_register_consumer+0x4cb/0x4e0 virt/lib/irqbypass.c:198 > kvm_irqfd_assign arch/x86/kvm/../../../virt/kvm/eventfd.c:417 [inline] > kvm_irqfd+0x137d/0x1e20 arch/x86/kvm/../../../virt/kvm/eventfd.c:578 > kvm_vm_ioctl+0x108c/0x1d70 arch/x86/kvm/../../../virt/kvm/kvm_main.c:3011 > vfs_ioctl fs/ioctl.c:45 [inline] > do_vfs_ioctl+0x1bf/0x1790 fs/ioctl.c:685 > SYSC_ioctl fs/ioctl.c:700 [inline] > SyS_ioctl+0x8f/0xc0 fs/ioctl.c:691 > entry_SYSCALL_64_fastpath+0x1f/0xc2 > RIP: 0033:0x4402b9 > RSP: 002b:00007fb73c4f9d98 EFLAGS: 00000297 ORIG_RAX: 0000000000000010 > RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00000000004402b9 > RDX: 0000000020ae3000 RSI: 000000004020ae76 RDI: 0000000000000008 > RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 > R10: 0000000000000000 R11: 0000000000000297 R12: 0000000000000000 > R13: 0000000000000000 R14: 00007fb73c4fa9c0 R15: 00007fb73c4fa700 > Object at ffff88006777dc80, in cache kmalloc-512 size: 512 > Allocated: > PID = 15766 > save_stack_trace+0x16/0x20 arch/x86/kernel/stacktrace.c:59 > save_stack+0x43/0xd0 mm/kasan/kasan.c:513 > set_track mm/kasan/kasan.c:525 [inline] > kasan_kmalloc+0xaa/0xd0 mm/kasan/kasan.c:616 > kmem_cache_alloc_trace+0x10b/0x6e0 mm/slab.c:3638 > kmalloc include/linux/slab.h:490 [inline] > kzalloc include/linux/slab.h:663 [inline] > kvm_irqfd_assign arch/x86/kvm/../../../virt/kvm/eventfd.c:296 [inline] > kvm_irqfd+0x16f/0x1e20 arch/x86/kvm/../../../virt/kvm/eventfd.c:578 > kvm_vm_ioctl+0x108c/0x1d70 arch/x86/kvm/../../../virt/kvm/kvm_main.c:3011 > vfs_ioctl fs/ioctl.c:45 [inline] > do_vfs_ioctl+0x1bf/0x1790 fs/ioctl.c:685 > SYSC_ioctl fs/ioctl.c:700 [inline] > SyS_ioctl+0x8f/0xc0 fs/ioctl.c:691 > entry_SYSCALL_64_fastpath+0x1f/0xc2 > Freed: > PID = 670 > save_stack_trace+0x16/0x20 arch/x86/kernel/stacktrace.c:59 > save_stack+0x43/0xd0 mm/kasan/kasan.c:513 > set_track mm/kasan/kasan.c:525 [inline] > kasan_slab_free+0x6f/0xb0 mm/kasan/kasan.c:589 > __cache_free mm/slab.c:3514 [inline] > kfree+0xd3/0x250 mm/slab.c:3831 > irqfd_shutdown+0x150/0x1c0 arch/x86/kvm/../../../virt/kvm/eventfd.c:148 > process_one_work+0xc06/0x1c40 kernel/workqueue.c:2096 > worker_thread+0x223/0x19f0 kernel/workqueue.c:2230 > kthread+0x334/0x400 kernel/kthread.c:229 > ret_from_fork+0x31/0x40 arch/x86/entry/entry_64.S:430 > Memory state around the buggy address: > ffff88006777dc80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb > ffff88006777dd00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >>ffff88006777dd80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb > ^ > ffff88006777de00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb > ffff88006777de80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc > ================================================================== > > > Here is correct link for reproducer program: > https://gist.githubusercontent.com/dvyukov/34114444518fa22baff19ae204cc46a6/raw/7826cbcd1cbc472dfa4972fe56371df3c94b70c7/gistfile1.txt Still happens regularly. On 093b995e3b55a0ae0670226ddfcb05bfbf0099ae (Mar 20): ================================================================== BUG: KASAN: use-after-free in irq_bypass_register_consumer+0x4f0/0x500 virt/lib/irqbypass.c:198 at addr ffff88006648ec38 Read of size 8 by task a.out/6857 CPU: 3 PID: 6857 Comm: a.out Not tainted 4.11.0-rc3+ #366 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:16 [inline] dump_stack+0x1b8/0x28d lib/dump_stack.c:52 kasan_object_err+0x1c/0x70 mm/kasan/report.c:166 print_address_description mm/kasan/report.c:210 [inline] kasan_report_error mm/kasan/report.c:294 [inline] kasan_report.part.2+0x1be/0x480 mm/kasan/report.c:316 kasan_report mm/kasan/report.c:337 [inline] __asan_report_load8_noabort+0x29/0x30 mm/kasan/report.c:337 irq_bypass_register_consumer+0x4f0/0x500 virt/lib/irqbypass.c:198 kvm_irqfd_assign arch/x86/kvm/../../../virt/kvm/eventfd.c:417 [inline] kvm_irqfd+0x1391/0x1d70 arch/x86/kvm/../../../virt/kvm/eventfd.c:572 kvm_vm_ioctl+0xe9c/0x1c60 arch/x86/kvm/../../../virt/kvm/kvm_main.c:3012 vfs_ioctl fs/ioctl.c:45 [inline] do_vfs_ioctl+0x1af/0x16d0 fs/ioctl.c:685 SYSC_ioctl fs/ioctl.c:700 [inline] SyS_ioctl+0x8f/0xc0 fs/ioctl.c:691 entry_SYSCALL_64_fastpath+0x1f/0xc2 RIP: 0033:0x4402b9 RSP: 002b:00007f0564cc2d98 EFLAGS: 00000297 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00000000004402b9 RDX: 0000000020ae3000 RSI: 000000004020ae76 RDI: 0000000000000007 RBP: 0000000000000086 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000297 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f0564cc39c0 R15: 00007f0564cc3700 Object at ffff88006648eac0, in cache kmalloc-512 size: 512 Allocated: PID = 6857 save_stack_trace+0x16/0x20 arch/x86/kernel/stacktrace.c:59 save_stack+0x43/0xd0 mm/kasan/kasan.c:517 set_track mm/kasan/kasan.c:529 [inline] kasan_kmalloc+0xbc/0xf0 mm/kasan/kasan.c:620 kmem_cache_alloc_trace+0x11a/0x720 mm/slab.c:3638 kmalloc include/linux/slab.h:490 [inline] kzalloc include/linux/slab.h:663 [inline] kvm_irqfd_assign arch/x86/kvm/../../../virt/kvm/eventfd.c:296 [inline] kvm_irqfd+0x16c/0x1d70 arch/x86/kvm/../../../virt/kvm/eventfd.c:572 kvm_vm_ioctl+0xe9c/0x1c60 arch/x86/kvm/../../../virt/kvm/kvm_main.c:3012 vfs_ioctl fs/ioctl.c:45 [inline] do_vfs_ioctl+0x1af/0x16d0 fs/ioctl.c:685 SYSC_ioctl fs/ioctl.c:700 [inline] SyS_ioctl+0x8f/0xc0 fs/ioctl.c:691 entry_SYSCALL_64_fastpath+0x1f/0xc2 Freed: PID = 1252 save_stack_trace+0x16/0x20 arch/x86/kernel/stacktrace.c:59 save_stack+0x43/0xd0 mm/kasan/kasan.c:517 set_track mm/kasan/kasan.c:529 [inline] kasan_slab_free+0x81/0xc0 mm/kasan/kasan.c:593 __cache_free mm/slab.c:3514 [inline] kfree+0xd7/0x250 mm/slab.c:3831 irqfd_shutdown+0x13c/0x1a0 arch/x86/kvm/../../../virt/kvm/eventfd.c:148 process_one_work+0xb20/0x1b40 kernel/workqueue.c:2097 worker_thread+0x1b4/0x1340 kernel/workqueue.c:2231 kthread+0x359/0x420 kernel/kthread.c:229 ret_from_fork+0x31/0x40 arch/x86/entry/entry_64.S:430 Memory state around the buggy address: ffff88006648eb00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88006648eb80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff88006648ec00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88006648ec80: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc ffff88006648ed00: fc fc fc fc fc fc fc fc fb fb fb fb fb fb fb fb ==================================================================
