Re: KASAN: use-after-free Read in update_blocked_averages
From: Dmitry Vyukov <dvyukov@google.com>
Date: 2018-11-11 18:24:34
Also in:
lkml
On Sun, Nov 11, 2018 at 10:18 AM, syzbot [off-list ref] wrote:
Hello, syzbot found the following crash on: HEAD commit: 12ceaf8864c2 infiniband: nes: Fix more direct skb list acc.. git tree: net-next console output: https://syzkaller.appspot.com/x/log.txt?x=15a82783400000 kernel config: https://syzkaller.appspot.com/x/.config?x=dcbea7daf3ea3e3e dashboard link: https://syzkaller.appspot.com/bug?extid=0dbf864d3b52555e8265 compiler: gcc (GCC) 8.0.1 20180413 (experimental) syz repro: https://syzkaller.appspot.com/x/repro.syz?x=137ae6d5400000 C reproducer: https://syzkaller.appspot.com/x/repro.c?x=15dbd77b400000
Looking at the reproducer this looks network related, +netdev
r0 = socket$inet6(0xa, 0x2, 0x0)
connect$inet6(r0, &(0x7f0000000100)={0xa, 0x0, 0x0, @dev, 0x6}, 0x1c)
connect$inet6(r0, &(0x7f0000000580)={0xa, 0x4e22, 0x0, @ipv4={[], [],
@local}}, 0x1c)
sendmmsg(r0, &(0x7f00000092c0), 0x4ff, 0x0)
IMPORTANT: if you fix the bug, please add the following tag to the commit: Reported-by: syzbot+0dbf864d3b52555e8265@syzkaller.appspotmail.com IPv6: ADDRCONF(NETDEV_UP): veth1: link is not ready IPv6: ADDRCONF(NETDEV_CHANGE): veth1: link becomes ready IPv6: ADDRCONF(NETDEV_CHANGE): veth0: link becomes ready 8021q: adding VLAN 0 to HW filter on device team0 ================================================================== BUG: KASAN: use-after-free in skip_blocked_update kernel/sched/fair.c:3324 [inline] BUG: KASAN: use-after-free in update_blocked_averages+0x1533/0x1e00 kernel/sched/fair.c:7400 kasan: CONFIG_KASAN_INLINE enabled Read of size 8 at addr ffff8801bf0d6ea0 by task syz-executor841/6015 kasan: GPF could be caused by NULL-ptr deref or user memory access CPU: 1 PID: 6015 Comm: syz-executor841 Not tainted 4.20.0-rc1+ #289 general protection fault: 0000 [#1] PREEMPT SMP KASAN Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 CPU: 0 PID: 6272 Comm: syz-executor841 Not tainted 4.20.0-rc1+ #289 Call Trace: Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x244/0x39d lib/dump_stack.c:113 RIP: 0010:vmalloc_fault+0x426/0x770 arch/x86/mm/fault.c:405 Code: e0 e8 fe 25 47 00 48 b8 00 00 00 00 00 88 ff ff 48 ba 00 00 00 00 00 fc ff df 48 01 c3 4d 21 e5 4c 01 eb 48 89 d9 48 c1 e9 03 <80> 3c 11 00 0f 85 b2 02 00 00 48 8b 1b 31 ff 49 89 dc 49 83 e4 9f RSP: 0018:ffff8801d9d624c8 EFLAGS: 00010002 RAX: ffff880000000000 RBX: 000f100180000040 RCX: 0001e20030000008 print_address_description.cold.7+0x9/0x1ff mm/kasan/report.c:256 RDX: dffffc0000000000 RSI: ffffffff813864c2 RDI: 0000000000000007 kasan_report_error mm/kasan/report.c:354 [inline] kasan_report.cold.8+0x242/0x309 mm/kasan/report.c:412 RBP: ffff8801d9d624f8 R08: ffff8801bbb56700 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: 000fffffc0000000 __asan_report_load8_noabort+0x14/0x20 mm/kasan/report.c:433 R13: 000f880180000000 R14: ffffc90001159838 R15: 1ffffffff12a3f98 skip_blocked_update kernel/sched/fair.c:3324 [inline] update_blocked_averages+0x1533/0x1e00 kernel/sched/fair.c:7400 FS: 0000000001f7d880(0000) GS:ffff8801dae00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffffc90001159838 CR3: 00000001ba705000 CR4: 00000000001406f0 Call Trace: Modules linked in: ---[ end trace f6450057874cc9c7 ]--- RIP: 0010:vmalloc_fault+0x426/0x770 arch/x86/mm/fault.c:405 Code: e0 e8 fe 25 47 00 48 b8 00 00 00 00 00 88 ff ff 48 ba 00 00 00 00 00 fc ff df 48 01 c3 4d 21 e5 4c 01 eb 48 89 d9 48 c1 e9 03 <80> 3c 11 00 0f 85 b2 02 00 00 48 8b 1b 31 ff 49 89 dc 49 83 e4 9f RSP: 0018:ffff8801d9d624c8 EFLAGS: 00010002 RAX: ffff880000000000 RBX: 000f100180000040 RCX: 0001e20030000008 RDX: dffffc0000000000 RSI: ffffffff813864c2 RDI: 0000000000000007 RBP: ffff8801d9d624f8 R08: ffff8801bbb56700 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: 000fffffc0000000 R13: 000f880180000000 R14: ffffc90001159838 R15: 1ffffffff12a3f98 FS: 0000000001f7d880(0000) GS:ffff8801dae00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffffc90001159838 CR3: 00000001ba705000 CR4: 00000000001406f0 --- 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@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+unsubscribe@googlegroups.com. To view this discussion on the web visit https://groups.google.com/d/msgid/syzkaller-bugs/000000000000fd464c057a679adb%40google.com. For more options, visit https://groups.google.com/d/optout.