Re: [syzbot] BUG: corrupted list in netif_napi_add
From: Dmitry Vyukov
Date: Mon Oct 25 2021 - 02:42:03 EST
On Sat, 23 Oct 2021 at 15:45, Hillf Danton <hdanton@xxxxxxxx> wrote:
>
> On Mon, 18 Oct 2021 17:04:19 +0300 Vlad Buslov wrote:
> >On Thu 14 Oct 2021 at 16:50, Paolo Abeni <pabeni@xxxxxxxxxx> wrote:
> >> On Wed, 2021-10-13 at 15:35 +0200, Daniel Borkmann wrote:
> >>> On 10/13/21 1:40 PM, syzbot wrote:
> >>> > Hello,
> >>> >
> >>> > syzbot found the following issue on:
> >>>
> >>> [ +Paolo/Toke wrt veth/XDP, +Jussi wrt bond/XDP, please take a look, thanks! ]
> >>
> >> For the records: Toke and me are actively investigating this issue and
> >> the other recent related one. So far we could not find anything
> >> relevant.
> >>
> >> The onluy note is that the reproducer is not extremelly reliable - I
> >> could not reproduce locally, and multiple syzbot runs on the same code
> >> give different results. Anyhow, so far the issue was only observerable
> >> on a specific 'next' commit which is currently "not reachable" from any
> >> branch. I'm wondering if the issue was caused by some incosistent
> >> status of such tree.
> >
> >Hi,
> >
> >We got a use-after-free with very similar trace [0] during nightly
> >regression. The issue happens when ip link up/down state is flipped
> >several times in loop and doesn't reproduce for me manually. The fact
> >that it didn't reproduce for me after running test ten times suggests
> >that it is either very hard to reproduce or that it is a result of some
> >interaction between several tests in our suite.
> >
> >[0]:
> >
> >[ 3187.779569] mlx5_core 0000:08:00.0 enp8s0f0: Link up
> > [ 3187.890694] ==================================================================
> > [ 3187.892518] BUG: KASAN: use-after-free in __list_add_valid+0xc3/0xf0
> > [ 3187.894132] Read of size 8 at addr ffff8881150b3fb8 by task ip/119618
> > [ 3187.895683]
> > [ 3187.896209] CPU: 0 PID: 119618 Comm: ip Not tainted 5.15.0-rc5_for_upstream_debug_2021_10_17_12_06 #1
> > [ 3187.898445] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.13.0-0-gf21b5a4aeb02-prebuilt.qemu.org 04/01/2014
> > [ 3187.901075] Call Trace:
> > [ 3187.901858] dump_stack_lvl+0x57/0x7d
> > [ 3187.902899] print_address_description.constprop.0+0x1f/0x140
> > [ 3187.904346] ? __list_add_valid+0xc3/0xf0
> > [ 3187.905439] ? __list_add_valid+0xc3/0xf0
> > [ 3187.906565] kasan_report.cold+0x83/0xdf
> > [ 3187.907619] ? __list_add_valid+0xc3/0xf0
> > [ 3187.908693] __list_add_valid+0xc3/0xf0
> > [ 3187.909765] netif_napi_add+0x399/0x9a0
> > [ 3187.910794] ? kmalloc_order_trace+0x6a/0x120
> > [ 3187.911944] mlx5e_open_channels+0x91b/0x2e10 [mlx5_core]
> > [ 3187.913872] ? rwlock_bug.part.0+0x90/0x90
> > [ 3187.914959] ? mlx5e_close_cq+0x80/0x80 [mlx5_core]
> > [ 3187.916584] ? mutex_is_locked+0x13/0x50
> > [ 3187.917703] mlx5e_open_locked+0x6a/0x1f0 [mlx5_core]
> > [ 3187.919368] mlx5e_open+0x35/0xb0 [mlx5_core]
> > [ 3187.920863] __dev_open+0x22f/0x420
> > [ 3187.921852] ? dev_set_rx_mode+0x80/0x80
> > [ 3187.922920] ? __mlx5_eswitch_set_vport_vlan+0x290/0x290 [mlx5_core]
> > [ 3187.924866] ? __local_bh_enable_ip+0xa2/0x100
> > [ 3187.926148] ? trace_hardirqs_on+0x32/0x120
> > [ 3187.927270] __dev_change_flags+0x451/0x670
> > [ 3187.928387] ? dev_set_allmulti+0x10/0x10
> > [ 3187.929480] ? rtnl_fill_vfinfo+0x936/0xdb0
> > [ 3187.930592] dev_change_flags+0x8b/0x150
> > [ 3187.931651] do_setlink+0x820/0x2d60
> > [ 3187.932631] ? rtnetlink_put_metrics+0x490/0x490
> > [ 3187.933852] ? lock_release+0x460/0x750
> > [ 3187.934881] ? kvm_async_pf_task_wake+0x410/0x410
> > [ 3187.936122] ? lock_downgrade+0x6e0/0x6e0
> > [ 3187.937203] ? do_raw_spin_unlock+0x54/0x220
> > [ 3187.938351] ? memset+0x20/0x40
> > [ 3187.939246] ? __nla_validate_parse+0xb2/0x22c0
> > [ 3187.940426] ? do_raw_spin_lock+0x126/0x270
> > [ 3187.941568] ? push_cpu_stop+0x830/0x830
> > [ 3187.942638] ? rwlock_bug.part.0+0x90/0x90
> > [ 3187.943733] ? devlink_compat_switch_id_get+0xbb/0x100
> > [ 3187.945065] ? nla_get_range_signed+0x540/0x540
> > [ 3187.946272] ? memcpy+0x39/0x60
> > [ 3187.947162] ? memset+0x20/0x40
> > [ 3187.948058] ? memset+0x20/0x40
> > [ 3187.948943] __rtnl_newlink+0xac0/0x1370
> > [ 3187.950038] ? entry_SYSCALL_64_after_hwframe+0x44/0xae
> > [ 3187.951380] ? rtnl_setlink+0x330/0x330
> > [ 3187.952417] ? deref_stack_reg+0x160/0x160
> > [ 3187.953534] ? deref_stack_reg+0xe6/0x160
> > [ 3187.954619] ? rcu_read_lock_sched_held+0x12/0x70
> > [ 3187.955848] ? lock_release+0x460/0x750
> > [ 3187.956886] ? is_bpf_text_address+0x54/0x110
> > [ 3187.958047] ? lock_downgrade+0x6e0/0x6e0
> > [ 3187.959133] ? entry_SYSCALL_64_after_hwframe+0x44/0xae
> > [ 3187.960469] ? deref_stack_reg+0x160/0x160
> > [ 3187.961592] ? is_bpf_text_address+0x73/0x110
> > [ 3187.962759] ? kernel_text_address+0xda/0x100
> > [ 3187.963920] ? __kernel_text_address+0xe/0x30
> > [ 3187.965069] ? unwind_get_return_address+0x56/0xa0
> > [ 3187.966334] ? __thaw_task+0x70/0x70
> > [ 3187.967320] ? arch_stack_walk+0x98/0xf0
> > [ 3187.968405] ? lock_downgrade+0x6e0/0x6e0
> > [ 3187.969510] ? trace_hardirqs_on+0x32/0x120
> > [ 3187.970644] ? rcu_read_lock_sched_held+0x12/0x70
> > [ 3187.971883] rtnl_newlink+0x5f/0x90
> > [ 3187.972866] rtnetlink_rcv_msg+0x32b/0x950
> > [ 3187.973968] ? deref_stack_reg+0x160/0x160
> > [ 3187.975088] ? rtnl_fdb_dump+0x830/0x830
> > [ 3187.976160] ? rcu_read_lock_sched_held+0x12/0x70
> > [ 3187.977393] ? lock_acquire+0x38d/0x4c0
> > [ 3187.978443] ? rcu_read_lock_sched_held+0x12/0x70
> > [ 3187.979685] ? lock_acquire+0x38d/0x4c0
> > [ 3187.980733] netlink_rcv_skb+0x11d/0x340
> > [ 3187.981812] ? rtnl_fdb_dump+0x830/0x830
> > [ 3187.982862] ? rcu_read_lock_sched_held+0x12/0x70
> > [ 3187.984105] ? netlink_ack+0x930/0x930
> > [ 3187.985136] ? netlink_deliver_tap+0x140/0xb10
> > [ 3187.986316] ? netlink_deliver_tap+0x14c/0xb10
> > [ 3187.987495] ? _copy_from_iter+0x282/0xbe0
> > [ 3187.988597] netlink_unicast+0x433/0x700
> > [ 3187.989693] ? netlink_attachskb+0x740/0x740
> > [ 3187.990819] ? __alloc_skb+0x117/0x2c0
> > [ 3187.991855] netlink_sendmsg+0x707/0xbf0
> > [ 3187.992921] ? netlink_unicast+0x700/0x700
> > [ 3187.994024] ? netlink_unicast+0x700/0x700
> > [ 3187.995121] sock_sendmsg+0xb0/0xe0
> > [ 3187.996091] ____sys_sendmsg+0x4fa/0x6d0
> > [ 3187.997163] ? iovec_from_user+0x136/0x280
> > [ 3187.998276] ? kernel_sendmsg+0x30/0x30
> > [ 3188.012806] ? __import_iovec+0x51/0x610
> > [ 3188.013858] ___sys_sendmsg+0x12e/0x1b0
> > [ 3188.014875] ? do_recvmmsg+0x500/0x500
> > [ 3188.015877] ? get_max_files+0x10/0x10
> > [ 3188.016866] ? kasan_record_aux_stack+0xab/0xc0
> > [ 3188.018108] ? call_rcu+0x87/0xd40
> > [ 3188.019041] ? task_work_run+0xc5/0x160
> > [ 3188.020044] ? exit_to_user_mode_prepare+0x1d9/0x1e0
> > [ 3188.021271] ? syscall_exit_to_user_mode+0x19/0x50
> > [ 3188.022563] ? do_syscall_64+0x4a/0x90
> > [ 3188.023559] ? entry_SYSCALL_64_after_hwframe+0x44/0xae
> > [ 3188.024858] ? rcu_read_lock_sched_held+0x12/0x70
> > [ 3188.026121] ? lock_release+0x460/0x750
> > [ 3188.027174] ? mntput_no_expire+0x113/0xb40
> > [ 3188.028302] ? lock_downgrade+0x6e0/0x6e0
> > [ 3188.029398] ? rwlock_bug.part.0+0x90/0x90
> > [ 3188.030555] ? rcu_read_lock_sched_held+0x12/0x70
> > [ 3188.031812] ? mntput_no_expire+0x132/0xb40
> > [ 3188.032940] ? __fget_light+0x51/0x220
> > [ 3188.033986] __sys_sendmsg+0xa4/0x120
> > [ 3188.034992] ? __sys_sendmsg_sock+0x20/0x20
> > [ 3188.036115] ? call_rcu+0x543/0xd40
> > [ 3188.037084] ? syscall_enter_from_user_mode+0x1d/0x50
> > [ 3188.038406] ? trace_hardirqs_on+0x32/0x120
> > [ 3188.039515] do_syscall_64+0x3d/0x90
> > [ 3188.040502] entry_SYSCALL_64_after_hwframe+0x44/0xae
> > [ 3188.041896] RIP: 0033:0x7f904ec94c17
> > [ 3188.042891] Code: 0c 00 f7 d8 64 89 02 48 c7 c0 ff ff ff ff eb b7 0f 1f 00 f3 0f 1e fa 64 8b 04 25 18 00 00 00 85 c0 75 10 b8 2e 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 51 c3 48 83 ec 28 89 54 24 1c 48 89 74 24 10
> > [ 3188.047412] RSP: 002b:00007ffc1a6c4a98 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
> > [ 3188.049361] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f904ec94c17
> > [ 3188.051121] RDX: 0000000000000000 RSI: 00007ffc1a6c4b00 RDI: 0000000000000003
> > [ 3188.052881] RBP: 00000000616c5eef R08: 0000000000000001 R09: 00007f904ed55a40
> > [ 3188.054645] R10: fffffffffffff3d6 R11: 0000000000000246 R12: 0000000000000001
> > [ 3188.056403] R13: 00007ffc1a6c51b0 R14: 00007ffc1a6c6c87 R15: 000000000048f520
> > [ 3188.058189]
> > [ 3188.058732] The buggy address belongs to the page:
> > [ 3188.059996] page:000000003ccb70fc refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x1150b3
> > [ 3188.062378] flags: 0x8000000000000000(zone=2)
> > [ 3188.063551] raw: 8000000000000000 0000000000000000 dead000000000122 0000000000000000
> > [ 3188.065548] raw: 0000000000000000 0000000000000000 00000000ffffffff 0000000000000000
> > [ 3188.067518] page dumped because: kasan: bad access detected
> > [ 3188.068930]
> > [ 3188.069481] Memory state around the buggy address:
> > [ 3188.070730] ffff8881150b3e80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
> > [ 3188.072618] ffff8881150b3f00: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
> > [ 3188.074508] >ffff8881150b3f80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
> > [ 3188.076378] ^
> > [ 3188.077711] ffff8881150b4000: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
> > [ 3188.079584] ffff8881150b4080: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
> > [ 3188.081470] ==================================================================
> > [ 3188.083406] ==================================================================
> > [ 3188.085280] BUG: KASAN: use-after-free in netif_napi_add+0x8b7/0x9a0
> > [ 3188.086952] Write of size 8 at addr ffff8881150b3fb8 by task ip/119618
> > [ 3188.089181]
> > [ 3188.089987] CPU: 0 PID: 119618 Comm: ip Tainted: G B 5.15.0-rc5_for_upstream_debug_2021_10_17_12_06 #1
> > [ 3188.092659] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.13.0-0-gf21b5a4aeb02-prebuilt.qemu.org 04/01/2014
> > [ 3188.095481] Call Trace:
> > [ 3188.096222] dump_stack_lvl+0x57/0x7d
> > [ 3188.097238] print_address_description.constprop.0+0x1f/0x140
> > [ 3188.098764] ? netif_napi_add+0x8b7/0x9a0
> > [ 3188.099862] ? netif_napi_add+0x8b7/0x9a0
> > [ 3188.100940] kasan_report.cold+0x83/0xdf
> > [ 3188.102041] ? netif_napi_add+0x8b7/0x9a0
> > [ 3188.103140] netif_napi_add+0x8b7/0x9a0
> > [ 3188.104180] ? kmalloc_order_trace+0x6a/0x120
> > [ 3188.105336] mlx5e_open_channels+0x91b/0x2e10 [mlx5_core]
> > [ 3188.107145] ? rwlock_bug.part.0+0x90/0x90
> > [ 3188.108238] ? mlx5e_close_cq+0x80/0x80 [mlx5_core]
> > [ 3188.109882] ? mutex_is_locked+0x13/0x50
> > [ 3188.110985] mlx5e_open_locked+0x6a/0x1f0 [mlx5_core]
> > [ 3188.112644] mlx5e_open+0x35/0xb0 [mlx5_core]
> > [ 3188.114215] __dev_open+0x22f/0x420
> > [ 3188.115186] ? dev_set_rx_mode+0x80/0x80
> > [ 3188.116247] ? __mlx5_eswitch_set_vport_vlan+0x290/0x290 [mlx5_core]
> > [ 3188.118252] ? __local_bh_enable_ip+0xa2/0x100
> > [ 3188.119438] ? trace_hardirqs_on+0x32/0x120
> > [ 3188.120554] __dev_change_flags+0x451/0x670
> > [ 3188.121705] ? dev_set_allmulti+0x10/0x10
> > [ 3188.122828] ? rtnl_fill_vfinfo+0x936/0xdb0
> > [ 3188.123943] dev_change_flags+0x8b/0x150
> > [ 3188.124995] do_setlink+0x820/0x2d60
> > [ 3188.126023] ? rtnetlink_put_metrics+0x490/0x490
> > [ 3188.127233] ? lock_release+0x460/0x750
> > [ 3188.128269] ? kvm_async_pf_task_wake+0x410/0x410
> > [ 3188.129502] ? lock_downgrade+0x6e0/0x6e0
> > [ 3188.130620] ? do_raw_spin_unlock+0x54/0x220
> > [ 3188.131781] ? memset+0x20/0x40
> > [ 3188.132663] ? __nla_validate_parse+0xb2/0x22c0
> > [ 3188.133894] ? do_raw_spin_lock+0x126/0x270
> > [ 3188.135066] ? push_cpu_stop+0x830/0x830
> > [ 3188.136136] ? rwlock_bug.part.0+0x90/0x90
> > [ 3188.137230] ? devlink_compat_switch_id_get+0xbb/0x100
> > [ 3188.138585] ? nla_get_range_signed+0x540/0x540
> > [ 3188.139780] ? memcpy+0x39/0x60
> > [ 3188.140683] ? memset+0x20/0x40
> > [ 3188.141580] ? memset+0x20/0x40
> > [ 3188.142517] __rtnl_newlink+0xac0/0x1370
> > [ 3188.143579] ? entry_SYSCALL_64_after_hwframe+0x44/0xae
> > [ 3188.144914] ? rtnl_setlink+0x330/0x330
> > [ 3188.145974] ? deref_stack_reg+0x160/0x160
> > [ 3188.147078] ? deref_stack_reg+0xe6/0x160
> > [ 3188.148157] ? rcu_read_lock_sched_held+0x12/0x70
> > [ 3188.149378] ? lock_release+0x460/0x750
> > [ 3188.150490] ? is_bpf_text_address+0x54/0x110
> > [ 3188.151648] ? lock_downgrade+0x6e0/0x6e0
> > [ 3188.152725] ? entry_SYSCALL_64_after_hwframe+0x44/0xae
> > [ 3188.154075] ? deref_stack_reg+0x160/0x160
> > [ 3188.155176] ? is_bpf_text_address+0x73/0x110
> > [ 3188.156353] ? kernel_text_address+0xda/0x100
> > [ 3188.157510] ? __kernel_text_address+0xe/0x30
> > [ 3188.158707] ? unwind_get_return_address+0x56/0xa0
> > [ 3188.159992] ? __thaw_task+0x70/0x70
> > [ 3188.160979] ? arch_stack_walk+0x98/0xf0
> > [ 3188.162072] ? lock_downgrade+0x6e0/0x6e0
> > [ 3188.163167] ? trace_hardirqs_on+0x32/0x120
> > [ 3188.164295] ? rcu_read_lock_sched_held+0x12/0x70
> > [ 3188.165546] rtnl_newlink+0x5f/0x90
> > [ 3188.166558] rtnetlink_rcv_msg+0x32b/0x950
> > [ 3188.167677] ? deref_stack_reg+0x160/0x160
> > [ 3188.168782] ? rtnl_fdb_dump+0x830/0x830
> > [ 3188.169857] ? rcu_read_lock_sched_held+0x12/0x70
> > [ 3188.171089] ? lock_acquire+0x38d/0x4c0
> > [ 3188.172131] ? rcu_read_lock_sched_held+0x12/0x70
> > [ 3188.173367] ? lock_acquire+0x38d/0x4c0
> > [ 3188.174472] netlink_rcv_skb+0x11d/0x340
> > [ 3188.175531] ? rtnl_fdb_dump+0x830/0x830
> > [ 3188.176592] ? rcu_read_lock_sched_held+0x12/0x70
> > [ 3188.177824] ? netlink_ack+0x930/0x930
> > [ 3188.178848] ? netlink_deliver_tap+0x140/0xb10
> > [ 3188.180013] ? netlink_deliver_tap+0x14c/0xb10
> > [ 3188.181188] ? _copy_from_iter+0x282/0xbe0
> > [ 3188.182351] netlink_unicast+0x433/0x700
> > [ 3188.183418] ? netlink_attachskb+0x740/0x740
> > [ 3188.184552] ? __alloc_skb+0x117/0x2c0
> > [ 3188.185606] netlink_sendmsg+0x707/0xbf0
> > [ 3188.186672] ? netlink_unicast+0x700/0x700
> > [ 3188.187783] ? netlink_unicast+0x700/0x700
> > [ 3188.188882] sock_sendmsg+0xb0/0xe0
> > [ 3188.189862] ____sys_sendmsg+0x4fa/0x6d0
> > [ 3188.190971] ? iovec_from_user+0x136/0x280
> > [ 3188.192074] ? kernel_sendmsg+0x30/0x30
> > [ 3188.193130] ? __import_iovec+0x51/0x610
> > [ 3188.194225] ___sys_sendmsg+0x12e/0x1b0
> > [ 3188.195267] ? do_recvmmsg+0x500/0x500
> > [ 3188.196301] ? get_max_files+0x10/0x10
> > [ 3188.197333] ? kasan_record_aux_stack+0xab/0xc0
> > [ 3188.198558] ? call_rcu+0x87/0xd40
> > [ 3188.199519] ? task_work_run+0xc5/0x160
> > [ 3188.200557] ? exit_to_user_mode_prepare+0x1d9/0x1e0
> > [ 3188.201872] ? syscall_exit_to_user_mode+0x19/0x50
> > [ 3188.203134] ? do_syscall_64+0x4a/0x90
> > [ 3188.204152] ? entry_SYSCALL_64_after_hwframe+0x44/0xae
> > [ 3188.205511] ? rcu_read_lock_sched_held+0x12/0x70
> > [ 3188.206782] ? lock_release+0x460/0x750
> > [ 3188.207870] ? mntput_no_expire+0x113/0xb40
> > [ 3188.209025] ? lock_downgrade+0x6e0/0x6e0
> > [ 3188.210272] ? rwlock_bug.part.0+0x90/0x90
> > [ 3188.211864] ? rcu_read_lock_sched_held+0x12/0x70
> > [ 3188.213644] ? mntput_no_expire+0x132/0xb40
> > [ 3188.215253] ? __fget_light+0x51/0x220
> > [ 3188.216535] __sys_sendmsg+0xa4/0x120
> > [ 3188.217574] ? __sys_sendmsg_sock+0x20/0x20
> > [ 3188.218707] ? call_rcu+0x543/0xd40
> > [ 3188.219679] ? syscall_enter_from_user_mode+0x1d/0x50
> > [ 3188.221004] ? trace_hardirqs_on+0x32/0x120
> > [ 3188.235475] do_syscall_64+0x3d/0x90
> > [ 3188.236463] entry_SYSCALL_64_after_hwframe+0x44/0xae
> > [ 3188.237744] RIP: 0033:0x7f904ec94c17
> > [ 3188.238693] Code: 0c 00 f7 d8 64 89 02 48 c7 c0 ff ff ff ff eb b7 0f 1f 00 f3 0f 1e fa 64 8b 04 25 18 00 00 00 85 c0 75 10 b8 2e 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 51 c3 48 83 ec 28 89 54 24 1c 48 89 74 24 10
> > [ 3188.242968] RSP: 002b:00007ffc1a6c4a98 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
> > [ 3188.244834] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f904ec94c17
> > [ 3188.246604] RDX: 0000000000000000 RSI: 00007ffc1a6c4b00 RDI: 0000000000000003
> > [ 3188.248362] RBP: 00000000616c5eef R08: 0000000000000001 R09: 00007f904ed55a40
> > [ 3188.250140] R10: fffffffffffff3d6 R11: 0000000000000246 R12: 0000000000000001
> > [ 3188.251889] R13: 00007ffc1a6c51b0 R14: 00007ffc1a6c6c87 R15: 000000000048f520
> > [ 3188.253667]
> > [ 3188.254215] The buggy address belongs to the page:
> > [ 3188.255460] page:000000003ccb70fc refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x1150b3
> > [ 3188.257812] flags: 0x8000000000000000(zone=2)
> > [ 3188.258985] raw: 8000000000000000 0000000000000000 dead000000000122 0000000000000000
> > [ 3188.260971] raw: 0000000000000000 0000000000000000 00000000ffffffff 0000000000000000
> > [ 3188.262993] page dumped because: kasan: bad access detected
> > [ 3188.264413]
> > [ 3188.264943] Memory state around the buggy address:
> > [ 3188.266203] ffff8881150b3e80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
> > [ 3188.268082] ffff8881150b3f00: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
> > [ 3188.269957] >ffff8881150b3f80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
> > [ 3188.271818] ^
> > [ 3188.273122] ffff8881150b4000: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
> > [ 3188.275000] ffff8881150b4080: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
> > [ 3188.276862] ==================================================================
> > [ 3188.371511] mlx5_core 0000:08:00.0 enp8s0f0: Link up
> > [ 3188.376126] IPv6: ADDRCONF(NETDEV_CHANGE): enp8s0f0: link becomes ready
> > [ 3188.430532] ==================================================================
> > [ 3188.432378] BUG: KASAN: use-after-free in __list_del_entry_valid+0x14b/0x180
> > [ 3188.434254] Read of size 8 at addr ffff8881150b3fb8 by task ip/119619
> > [ 3188.435826]
> > [ 3188.436365] CPU: 3 PID: 119619 Comm: ip Tainted: G B 5.15.0-rc5_for_upstream_debug_2021_10_17_12_06 #1
> > [ 3188.439688] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.13.0-0-gf21b5a4aeb02-prebuilt.qemu.org 04/01/2014
> > [ 3188.442423] Call Trace:
> > [ 3188.443172] dump_stack_lvl+0x57/0x7d
> > [ 3188.444186] print_address_description.constprop.0+0x1f/0x140
> > [ 3188.445703] ? __list_del_entry_valid+0x14b/0x180
> > [ 3188.447004] ? __list_del_entry_valid+0x14b/0x180
> > [ 3188.448255] kasan_report.cold+0x83/0xdf
> > [ 3188.449323] ? __list_del_entry_valid+0x14b/0x180
> > [ 3188.450670] __list_del_entry_valid+0x14b/0x180
> > [ 3188.451887] ? _raw_spin_unlock+0x1f/0x30
> > [ 3188.452969] __netif_napi_del.part.0+0xec/0x4a0
> > [ 3188.454453] mlx5e_close_channel+0x7d/0xd0 [mlx5_core]
> > [ 3188.456988] mlx5e_close_channels+0xf9/0x200 [mlx5_core]
> > [ 3188.459599] mlx5e_close_locked+0x101/0x130 [mlx5_core]
> > [ 3188.462156] mlx5e_close+0xad/0x100 [mlx5_core]
> > [ 3188.463961] __dev_close_many+0x18e/0x2b0
> > [ 3188.465045] ? list_netdevice+0x3a0/0x3a0
> > [ 3188.466187] ? __mlx5_eswitch_set_vport_vlan+0x290/0x290 [mlx5_core]
> > [ 3188.468156] ? __local_bh_enable_ip+0xa2/0x100
> > [ 3188.469333] ? trace_hardirqs_on+0x32/0x120
> > [ 3188.470496] __dev_change_flags+0x254/0x670
> > [ 3188.471605] ? dev_set_allmulti+0x10/0x10
> > [ 3188.472692] ? rtnl_fill_vfinfo+0x936/0xdb0
> > [ 3188.473854] dev_change_flags+0x8b/0x150
> > [ 3188.474965] do_setlink+0x820/0x2d60
> > [ 3188.475950] ? rtnetlink_put_metrics+0x490/0x490
> > [ 3188.477165] ? lock_release+0x460/0x750
> > [ 3188.478306] ? kvm_async_pf_task_wake+0x410/0x410
> > [ 3188.479542] ? lock_downgrade+0x6e0/0x6e0
> > [ 3188.480615] ? do_raw_spin_unlock+0x54/0x220
> > [ 3188.481790] ? memset+0x20/0x40
> > [ 3188.482963] ? __nla_validate_parse+0xb2/0x22c0
> > [ 3188.484167] ? do_raw_spin_lock+0x126/0x270
> > [ 3188.485281] ? push_cpu_stop+0x830/0x830
> > [ 3188.486457] ? rwlock_bug.part.0+0x90/0x90
> > [ 3188.487557] ? devlink_compat_switch_id_get+0xbb/0x100
> > [ 3188.488894] ? nla_get_range_signed+0x540/0x540
> > [ 3188.490168] ? memcpy+0x39/0x60
> > [ 3188.491083] ? memset+0x20/0x40
> > [ 3188.491966] ? memset+0x20/0x40
> > [ 3188.492855] __rtnl_newlink+0xac0/0x1370
> > [ 3188.493987] ? entry_SYSCALL_64_after_hwframe+0x44/0xae
> > [ 3188.495384] ? rtnl_setlink+0x330/0x330
> > [ 3188.496446] ? deref_stack_reg+0x160/0x160
> > [ 3188.497551] ? deref_stack_reg+0xe6/0x160
> > [ 3188.498713] ? rcu_read_lock_sched_held+0x12/0x70
> > [ 3188.499929] ? lock_release+0x460/0x750
> > [ 3188.501232] ? is_bpf_text_address+0x54/0x110
> > [ 3188.502735] ? lock_downgrade+0x6e0/0x6e0
> > [ 3188.503831] ? entry_SYSCALL_64_after_hwframe+0x44/0xae
> > [ 3188.505157] ? deref_stack_reg+0x160/0x160
> > [ 3188.506298] ? is_bpf_text_address+0x73/0x110
> > [ 3188.507459] ? kernel_text_address+0xda/0x100
> > [ 3188.508615] ? __kernel_text_address+0xe/0x30
> > [ 3188.509776] ? unwind_get_return_address+0x56/0xa0
> > [ 3188.511047] ? __thaw_task+0x70/0x70
> > [ 3188.512033] ? arch_stack_walk+0x98/0xf0
> > [ 3188.513059] ? lock_downgrade+0x6e0/0x6e0
> > [ 3188.514191] ? trace_hardirqs_on+0x32/0x120
> > [ 3188.515303] ? rcu_read_lock_sched_held+0x12/0x70
> > [ 3188.516524] rtnl_newlink+0x5f/0x90
> > [ 3188.517513] rtnetlink_rcv_msg+0x32b/0x950
> > [ 3188.518652] ? deref_stack_reg+0x160/0x160
> > [ 3188.519761] ? rtnl_fdb_dump+0x830/0x830
> > [ 3188.520816] ? rcu_read_lock_sched_held+0x12/0x70
> > [ 3188.522119] ? lock_acquire+0x38d/0x4c0
> > [ 3188.523211] ? rcu_read_lock_sched_held+0x12/0x70
> > [ 3188.524435] ? lock_acquire+0x38d/0x4c0
> > [ 3188.525498] netlink_rcv_skb+0x11d/0x340
> > [ 3188.526649] ? rtnl_fdb_dump+0x830/0x830
> > [ 3188.527722] ? rcu_read_lock_sched_held+0x12/0x70
> > [ 3188.528949] ? netlink_ack+0x930/0x930
> > [ 3188.530055] ? netlink_deliver_tap+0x140/0xb10
> > [ 3188.531347] ? netlink_deliver_tap+0x14c/0xb10
> > [ 3188.532549] ? _copy_from_iter+0x282/0xbe0
> > [ 3188.533711] netlink_unicast+0x433/0x700
> > [ 3188.534845] ? netlink_attachskb+0x740/0x740
> > [ 3188.535987] ? __alloc_skb+0x117/0x2c0
> > [ 3188.537006] netlink_sendmsg+0x707/0xbf0
> > [ 3188.538150] ? netlink_unicast+0x700/0x700
> > [ 3188.539337] ? netlink_unicast+0x700/0x700
> > [ 3188.540448] sock_sendmsg+0xb0/0xe0
> > [ 3188.541424] ____sys_sendmsg+0x4fa/0x6d0
> > [ 3188.542743] ? iovec_from_user+0x136/0x280
> > [ 3188.543932] ? kernel_sendmsg+0x30/0x30
> > [ 3188.544963] ? __import_iovec+0x51/0x610
> > [ 3188.546063] ___sys_sendmsg+0x12e/0x1b0
> > [ 3188.547189] ? do_recvmmsg+0x500/0x500
> > [ 3188.548209] ? get_max_files+0x10/0x10
> > [ 3188.549226] ? kasan_record_aux_stack+0xab/0xc0
> > [ 3188.550547] ? call_rcu+0x87/0xd40
> > [ 3188.551509] ? task_work_run+0xc5/0x160
> > [ 3188.552546] ? exit_to_user_mode_prepare+0x1d9/0x1e0
> > [ 3188.553896] ? syscall_exit_to_user_mode+0x19/0x50
> > [ 3188.555195] ? do_syscall_64+0x4a/0x90
> > [ 3188.556206] ? entry_SYSCALL_64_after_hwframe+0x44/0xae
> > [ 3188.557634] ? rcu_read_lock_sched_held+0x12/0x70
> > [ 3188.558903] ? lock_release+0x460/0x750
> > [ 3188.559948] ? mntput_no_expire+0x113/0xb40
> > [ 3188.561059] ? lock_downgrade+0x6e0/0x6e0
> > [ 3188.562231] ? rwlock_bug.part.0+0x90/0x90
> > [ 3188.563338] ? rcu_read_lock_sched_held+0x12/0x70
> > [ 3188.564583] ? mntput_no_expire+0x132/0xb40
> > [ 3188.565731] ? __fget_light+0x51/0x220
> > [ 3188.566858] __sys_sendmsg+0xa4/0x120
> > [ 3188.567878] ? __sys_sendmsg_sock+0x20/0x20
> > [ 3188.568995] ? call_rcu+0x543/0xd40
> > [ 3188.570047] ? syscall_enter_from_user_mode+0x1d/0x50
> > [ 3188.571387] ? trace_hardirqs_on+0x32/0x120
> > [ 3188.572502] do_syscall_64+0x3d/0x90
> > [ 3188.573491] entry_SYSCALL_64_after_hwframe+0x44/0xae
> > [ 3188.574916] RIP: 0033:0x7fc68ffd4c17
> > [ 3188.575900] Code: 0c 00 f7 d8 64 89 02 48 c7 c0 ff ff ff ff eb b7 0f 1f 00 f3 0f 1e fa 64 8b 04 25 18 00 00 00 85 c0 75 10 b8 2e 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 51 c3 48 83 ec 28 89 54 24 1c 48 89 74 24 10
> > [ 3188.580625] RSP: 002b:00007ffd26634f18 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
> > [ 3188.582945] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007fc68ffd4c17
> > [ 3188.585684] RDX: 0000000000000000 RSI: 00007ffd26634f80 RDI: 0000000000000003
> > [ 3188.587965] RBP: 00000000616c5eef R08: 0000000000000001 R09: 00007fc690095a40
> > [ 3188.589788] R10: fffffffffffff3d6 R11: 0000000000000246 R12: 0000000000000001
> > [ 3188.591618] R13: 00007ffd26635630 R14: 00007ffd26635c85 R15: 000000000048f520
> > [ 3188.593365]
> > [ 3188.593953] The buggy address belongs to the page:
> > [ 3188.595288] page:000000003ccb70fc refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x1150b3
> > [ 3188.597966] flags: 0x8000000000000000(zone=2)
> > [ 3188.599643] raw: 8000000000000000 0000000000000000 dead000000000122 0000000000000000
> > [ 3188.601766] raw: 0000000000000000 0000000000000000 00000000ffffffff 0000000000000000
> > [ 3188.603786] page dumped because: kasan: bad access detected
> > [ 3188.622507]
> > [ 3188.623291] Memory state around the buggy address:
> > [ 3188.625031] ffff8881150b3e80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
> > [ 3188.627617] ffff8881150b3f00: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
> > [ 3188.630275] >ffff8881150b3f80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
> > [ 3188.632956] ^
> > [ 3188.634838] ffff8881150b4000: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
> > [ 3188.637544] ffff8881150b4080: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
> > [ 3188.640221] ==================================================================
> >
> >[...]
> >
> > [ 3188.574916] RIP: 0033:0x7fc68ffd4c17
> > [ 3188.237744] RIP: 0033:0x7f904ec94c17
>
> Dmitry, what addresses are these RIPs pointing to?
This report did not come from syzkaller/syzbot. We need to ask Vlad.
For syzkaller/syzbot I wouldn't be able to answer such a question. But
I guess it's just a code that executes the sendmsg syscall instruction
in user-space. What aspect of that code are you interested in?