#syz dup: KASAN: use-after-free Read in do_general_protection On Sat, May 26, 2018 at 11:16 AM, syzbot <syzbot+a5373bacd7643643b238@xxxxxxxxxxxxxxxxxxxxxxxxx> wrote: > Hello, > > syzbot found the following crash on: > > HEAD commit: 62d18ecfa641 Merge tag 'arm64-fixes' of git://git.kernel.o.. > git tree: upstream > console output: https://syzkaller.appspot.com/x/log.txt?x=1093ccb7800000 > kernel config: https://syzkaller.appspot.com/x/.config?x=982e2df1b9e60b02 > dashboard link: https://syzkaller.appspot.com/bug?extid=a5373bacd7643643b238 > compiler: gcc (GCC) 8.0.1 20180413 (experimental) > userspace arch: i386 > syzkaller repro:https://syzkaller.appspot.com/x/repro.syz?x=1067742f800000 > > IMPORTANT: if you fix the bug, please add the following tag to the commit: > Reported-by: syzbot+a5373bacd7643643b238@xxxxxxxxxxxxxxxxxxxxxxxxx > > IPv6: ADDRCONF(NETDEV_UP): veth0: link is not ready > IPv6: ADDRCONF(NETDEV_CHANGE): veth0: link becomes ready > IPv6: ADDRCONF(NETDEV_CHANGE): bond0: link becomes ready > 8021q: adding VLAN 0 to HW filter on device team0 > ================================================================== > BUG: KASAN: stack-out-of-bounds in do_general_protection+0x2ac/0x2f0 > arch/x86/kernel/traps.c:538 > Read of size 8 at addr ffff8801b21273f8 by task syz-executor0/5106 > > CPU: 0 PID: 5106 Comm: syz-executor0 Not tainted 4.17.0-rc6+ #92 > 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+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 > do_general_protection+0x2ac/0x2f0 arch/x86/kernel/traps.c:538 > general_protection+0x1e/0x30 arch/x86/entry/entry_64.S:1159 > RIP: 0010:msr_write_intercepted arch/x86/kvm/vmx.c:2132 [inline] > RIP: 0010:vmx_vcpu_run+0xa12/0x25c0 arch/x86/kvm/vmx.c:9879 > RSP: 0018:ffff8801b2127410 EFLAGS: 00010006 > RAX: dffffc0000000000 RBX: 0000000010000000 RCX: ffffffff811f76f2 > RDX: 000000000836b156 RSI: ffffffff811f76ff RDI: 0000000000000005 > RBP: ffff8801b2127508 R08: ffff8801cf7a6500 R09: 0000000000000000 > R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 > R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 > mmu_notifier_release include/linux/mmu_notifier.h:244 [inline] > exit_mmap+0xa4/0x5a0 mm/mmap.c:3057 > __mmput kernel/fork.c:961 [inline] > mmput+0x251/0x610 kernel/fork.c:982 > exit_mm kernel/exit.c:544 [inline] > do_exit+0xe98/0x2730 kernel/exit.c:852 > do_group_exit+0x16f/0x430 kernel/exit.c:968 > __do_sys_exit_group kernel/exit.c:979 [inline] > __se_sys_exit_group kernel/exit.c:977 [inline] > __ia32_sys_exit_group+0x3e/0x50 kernel/exit.c:977 > do_syscall_32_irqs_on arch/x86/entry/common.c:323 [inline] > do_fast_syscall_32+0x345/0xf9b arch/x86/entry/common.c:394 > entry_SYSENTER_compat+0x70/0x7f arch/x86/entry/entry_64_compat.S:139 > RIP: 0023:0xf7f88cb9 > RSP: 002b:00000000f7f7fa8c EFLAGS: 00000286 ORIG_RAX: 00000000000000fc > RAX: ffffffffffffffda RBX: 000000000000000b RCX: 0000000000000000 > RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 > RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 > R10: 0000000000000000 R11: 0000000000000292 R12: 0000000000000000 > R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 > > The buggy address belongs to the page: > page:ffffea0006c849c0 count:0 mapcount:0 mapping:0000000000000000 index:0x0 > flags: 0x2fffc0000000000() > raw: 02fffc0000000000 0000000000000000 0000000000000000 00000000ffffffff > raw: 0000000000000000 ffffea0006c80101 0000000000000000 0000000000000000 > page dumped because: kasan: bad access detected > > Memory state around the buggy address: > ffff8801b2127280: 00 f2 00 00 00 00 00 00 00 00 00 00 00 00 f3 00 > ffff8801b2127300: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 >> >> ffff8801b2127380: 00 00 00 00 00 00 00 00 f1 f1 f1 f1 f8 f2 f2 f2 > > ^ > ffff8801b2127400: f2 f2 f2 f2 f8 f2 f2 f2 f2 f2 f2 f2 00 f2 f2 f2 > ffff8801b2127480: f2 f2 f2 f2 00 f2 f2 f2 f3 f3 f3 f3 00 00 00 00 > ================================================================== > > > --- > 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 syzkaller@xxxxxxxxxxxxxxxx. > > 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+unsubscribe@xxxxxxxxxxxxxxxx. > To view this discussion on the web visit > https://groups.google.com/d/msgid/syzkaller-bugs/00000000000065ecae056d185548%40google.com. > For more options, visit https://groups.google.com/d/optout.
