KASAN: use-after-free Read in run_filter

Status: upstream: reported syz repro on 2020/09/05 09:35
First crash: 1119d, last: 515d
Fix bisection: failed (error log, bisect log)

Sample crash report:
BUG: KASAN: use-after-free in __read_once_size include/linux/compiler.h:193 [inline]
BUG: KASAN: use-after-free in run_filter+0x2f3/0x310 net/packet/af_packet.c:2002
Read of size 8 at addr ffff88808417a680 by task syz-executor.2/4047

CPU: 0 PID: 4047 Comm: syz-executor.2 Not tainted 4.19.143-syzkaller #0
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+0x1fc/0x2fe lib/dump_stack.c:118
 print_address_description.cold+0x54/0x219 mm/kasan/report.c:256
 kasan_report_error.cold+0x8a/0x1c7 mm/kasan/report.c:354
 kasan_report mm/kasan/report.c:412 [inline]
 __asan_report_load8_noabort+0x88/0x90 mm/kasan/report.c:433
 __read_once_size include/linux/compiler.h:193 [inline]
 run_filter+0x2f3/0x310 net/packet/af_packet.c:2002
 packet_rcv+0x24b/0x1480 net/packet/af_packet.c:2077
 dev_queue_xmit_nit+0x756/0xa20 net/core/dev.c:2050
 xmit_one net/core/dev.c:3252 [inline]
 dev_hard_start_xmit+0xaa/0x920 net/core/dev.c:3272
 __dev_queue_xmit+0x269d/0x2e00 net/core/dev.c:3838
 hsr_xmit net/hsr/hsr_forward.c:237 [inline]
 hsr_forward_do net/hsr/hsr_forward.c:295 [inline]
 hsr_forward_skb+0xd2d/0x1c30 net/hsr/hsr_forward.c:373
 send_hsr_supervision_frame+0x917/0xf70 net/hsr/hsr_device.c:321
 hsr_announce+0x125/0x3a0 net/hsr/hsr_device.c:350
 call_timer_fn+0x177/0x700 kernel/time/timer.c:1338
 expire_timers+0x243/0x4e0 kernel/time/timer.c:1375
 __run_timers kernel/time/timer.c:1703 [inline]
 run_timer_softirq+0x21c/0x670 kernel/time/timer.c:1716
 __do_softirq+0x26c/0x9a0 kernel/softirq.c:292
 invoke_softirq kernel/softirq.c:372 [inline]
 irq_exit+0x215/0x260 kernel/softirq.c:412
 exiting_irq arch/x86/include/asm/apic.h:544 [inline]
 smp_apic_timer_interrupt+0x136/0x550 arch/x86/kernel/apic/apic.c:1094
 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:894
RIP: 0010:arch_local_irq_restore arch/x86/include/asm/paravirt.h:789 [inline]
RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:160 [inline]
RIP: 0010:_raw_spin_unlock_irqrestore+0xa3/0xe0 kernel/locking/spinlock.c:184
Code: 48 c7 c0 48 5b d2 88 48 ba 00 00 00 00 00 fc ff df 48 c1 e8 03 80 3c 10 00 75 2f 48 83 3d bc bd 94 01 00 74 15 48 89 df 57 9d <0f> 1f 44 00 00 eb b2 e8 5a c1 c2 f9 eb c0 0f 0b 0f 0b 48 c7 c7 48
RSP: 0018:ffff88808e2bf650 EFLAGS: 00000282 ORIG_RAX: ffffffffffffff13
RAX: 1ffffffff11a4b69 RBX: 0000000000000282 RCX: 1ffff11010d0254d
RDX: dffffc0000000000 RSI: ffff888086812a70 RDI: 0000000000000282
RBP: ffffffff88d97058 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000003068
R13: ffff888083593248 R14: 0000000000000000 R15: dffffc0000000000
 __rcu_read_unlock+0x158/0x160 kernel/rcu/tree_plugin.h:428
 rcu_read_unlock include/linux/rcupdate.h:680 [inline]
 d_alloc_parallel+0x74e/0x19e0 fs/dcache.c:2530
 __lookup_slow+0x18d/0x4a0 fs/namei.c:1655
 lookup_slow fs/namei.c:1689 [inline]
 walk_component+0x7ac/0xda0 fs/namei.c:1811
 link_path_walk.part.0+0x901/0x1230 fs/namei.c:2142
 link_path_walk fs/namei.c:2073 [inline]
 path_openat+0x1db/0x2df0 fs/namei.c:3536
 do_filp_open+0x18c/0x3f0 fs/namei.c:3567
 do_sys_open+0x3b3/0x520 fs/open.c:1085
 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293
RIP: 0033:0x417101
Code: 75 14 b8 02 00 00 00 0f 05 48 3d 01 f0 ff ff 0f 83 04 19 00 00 c3 48 83 ec 08 e8 0a fa ff ff 48 89 04 24 b8 02 00 00 00 0f 05 <48> 8b 3c 24 48 89 c2 e8 53 fa ff ff 48 89 d0 48 83 c4 08 48 3d 01
RSP: 002b:00007fdccacfbc10 EFLAGS: 00000293 ORIG_RAX: 0000000000000002
RAX: ffffffffffffffda RBX: 000000000118cf40 RCX: 0000000000417101
RDX: 0000000000000001 RSI: 0000000000000000 RDI: 00000000004c21ff
RBP: 000000000118cf80 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000293 R12: 000000000118cf4c
R13: 00007ffe8ff4ef2f R14: 00007fdccacfc9c0 R15: 000000000118cf4c

Allocated by task 4044:
 __do_kmalloc mm/slab.c:3727 [inline]
 __kmalloc+0x15a/0x3c0 mm/slab.c:3736
 kmalloc include/linux/slab.h:520 [inline]
 sk_prot_alloc+0x1e2/0x2d0 net/core/sock.c:1466
 sk_alloc+0x36/0xec0 net/core/sock.c:1520
 packet_create+0x117/0x850 net/packet/af_packet.c:3252
 __sock_create+0x3d8/0x740 net/socket.c:1276
 sock_create net/socket.c:1316 [inline]
 __sys_socket+0xef/0x200 net/socket.c:1346
 __do_sys_socket net/socket.c:1355 [inline]
 __se_sys_socket net/socket.c:1353 [inline]
 __x64_sys_socket+0x6f/0xb0 net/socket.c:1353
 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293

Freed by task 4039:
 __cache_free mm/slab.c:3503 [inline]
 kfree+0xcc/0x210 mm/slab.c:3822
 sk_prot_free net/core/sock.c:1503 [inline]
 __sk_destruct+0x5ff/0x810 net/core/sock.c:1584
 sk_destruct net/core/sock.c:1599 [inline]
 __sk_free+0x165/0x3b0 net/core/sock.c:1610
 sk_free+0x3b/0x50 net/core/sock.c:1621
 sock_put include/net/sock.h:1711 [inline]
 packet_release+0x890/0xb70 net/packet/af_packet.c:3081
 __sock_release+0xcd/0x2a0 net/socket.c:579
 sock_close+0x15/0x20 net/socket.c:1140
 __fput+0x2ce/0x890 fs/file_table.c:278
 task_work_run+0x148/0x1c0 kernel/task_work.c:113
 tracehook_notify_resume include/linux/tracehook.h:193 [inline]
 exit_to_usermode_loop+0x251/0x2a0 arch/x86/entry/common.c:167
 prepare_exit_to_usermode arch/x86/entry/common.c:198 [inline]
 syscall_return_slowpath arch/x86/entry/common.c:271 [inline]
 do_syscall_64+0x538/0x620 arch/x86/entry/common.c:296

The buggy address belongs to the object at ffff88808417a480
 which belongs to the cache kmalloc-2048 of size 2048
The buggy address is located 512 bytes inside of
 2048-byte region [ffff88808417a480, ffff88808417ac80)
The buggy address belongs to the page:
page:ffffea0002105e80 count:1 mapcount:0 mapping:ffff88812c39cc40 index:0x0 compound_mapcount: 0
flags: 0xfffe0000008100(slab|head)
raw: 00fffe0000008100 ffffea0002254b88 ffffea000269dd88 ffff88812c39cc40
raw: 0000000000000000 ffff88808417a480 0000000100000003 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff88808417a580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88808417a600: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff88808417a680: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88808417a700: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88808417a780: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb

Crashes (2):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2020/09/05 09:34 linux-4.19.y c37da90efff5 abf9ba4f .config console log report syz ci2-linux-4-19
2022/05/02 03:34 linux-4.19.y 3f8a27f9e27b 2df221f6 .config console log report info ci2-linux-4-19 KASAN: use-after-free Read in run_filter
* Struck through repros no longer work on HEAD.