syzbot


KASAN: use-after-free Write in virtio_transport_recv_pkt

Status: upstream: reported C repro on 2024/04/03 23:05
Bug presence: origin:upstream
[Documentation on labels]
Reported-by: syzbot+9d13849d0e9e0ec75d47@syzkaller.appspotmail.com
First crash: 218d, last: 9d04h
Bug presence (2)
Date Name Commit Repro Result
2024/04/03 lts (merge base) 883d1a956208 C [report] KASAN: use-after-free Write in virtio_transport_recv_pkt
2024/04/03 upstream (ToT) c85af715cac0 C [report] KASAN: slab-use-after-free Write in virtio_transport_recv_pkt
Similar bugs (3)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
android-5-10 KASAN: use-after-free Write in virtio_transport_recv_pkt C inconclusive 1 27d 218d 0/2 upstream: reported C repro on 2024/04/03 23:46
android-5-15 KASAN: use-after-free Write in virtio_transport_recv_pkt origin:upstream C error 1 62d 218d 0/2 upstream: reported C repro on 2024/04/04 06:14
upstream KMSAN: uninit-value in virtio_transport_recv_pkt net C 20713 364d 378d 25/28 fixed on 2023/12/21 03:45
Last patch testing requests (1)
Created Duration User Patch Repo Result
2024/04/18 00:28 8m retest repro android14-6.1 report log
Fix bisection attempts (5)
Created Duration User Patch Repo Result
2024/10/30 16:19 1h25m bisect fix android14-6.1 OK (0) job log log
2024/09/30 00:18 42m bisect fix android14-6.1 OK (0) job log log
2024/08/22 04:13 49m bisect fix android14-6.1 OK (0) job log log
2024/07/11 17:59 1h38m bisect fix android14-6.1 OK (0) job log log
2024/05/23 06:01 1h31m bisect fix android14-6.1 OK (0) job log log

Sample crash report:
==================================================================
BUG: KASAN: use-after-free in instrument_atomic_read_write include/linux/instrumented.h:102 [inline]
BUG: KASAN: use-after-free in atomic_try_cmpxchg_acquire include/linux/atomic/atomic-instrumented.h:541 [inline]
BUG: KASAN: use-after-free in queued_spin_lock include/asm-generic/qspinlock.h:111 [inline]
BUG: KASAN: use-after-free in do_raw_spin_lock include/linux/spinlock.h:186 [inline]
BUG: KASAN: use-after-free in __raw_spin_lock_bh include/linux/spinlock_api_smp.h:127 [inline]
BUG: KASAN: use-after-free in _raw_spin_lock_bh+0x97/0x1b0 kernel/locking/spinlock.c:178
Write of size 4 at addr ffff88812648c708 by task kworker/0:0/6

CPU: 0 PID: 6 Comm: kworker/0:0 Not tainted 6.1.75-syzkaller-00112-gaf361f9a1066 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024
Workqueue: vsock-loopback vsock_loopback_work
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x151/0x1b7 lib/dump_stack.c:106
 print_address_description mm/kasan/report.c:316 [inline]
 print_report+0x158/0x4e0 mm/kasan/report.c:427
 kasan_report+0x13c/0x170 mm/kasan/report.c:531
 kasan_check_range+0x294/0x2a0 mm/kasan/generic.c:189
 __kasan_check_write+0x14/0x20 mm/kasan/shadow.c:37
 instrument_atomic_read_write include/linux/instrumented.h:102 [inline]
 atomic_try_cmpxchg_acquire include/linux/atomic/atomic-instrumented.h:541 [inline]
 queued_spin_lock include/asm-generic/qspinlock.h:111 [inline]
 do_raw_spin_lock include/linux/spinlock.h:186 [inline]
 __raw_spin_lock_bh include/linux/spinlock_api_smp.h:127 [inline]
 _raw_spin_lock_bh+0x97/0x1b0 kernel/locking/spinlock.c:178
 spin_lock_bh include/linux/spinlock.h:355 [inline]
 virtio_transport_space_update net/vmw_vsock/virtio_transport_common.c:1171 [inline]
 virtio_transport_recv_pkt+0x6d3/0x4130 net/vmw_vsock/virtio_transport_common.c:1307
 vsock_loopback_work+0x37d/0x3f0 net/vmw_vsock/vsock_loopback.c:137
 process_one_work+0x73d/0xcb0 kernel/workqueue.c:2299
 worker_thread+0xa60/0x1260 kernel/workqueue.c:2446
 kthread+0x26d/0x300 kernel/kthread.c:386
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:306
 </TASK>

Allocated by task 5525:
 kasan_save_stack mm/kasan/common.c:45 [inline]
 kasan_set_track+0x4b/0x70 mm/kasan/common.c:52
 kasan_save_alloc_info+0x1f/0x30 mm/kasan/generic.c:505
 ____kasan_kmalloc mm/kasan/common.c:379 [inline]
 __kasan_kmalloc+0x9c/0xb0 mm/kasan/common.c:388
 kasan_kmalloc include/linux/kasan.h:212 [inline]
 kmalloc_trace+0x44/0xa0 mm/slab_common.c:1052
 kmalloc include/linux/slab.h:553 [inline]
 kzalloc include/linux/slab.h:689 [inline]
 virtio_transport_do_socket_init+0x56/0x2d0 net/vmw_vsock/virtio_transport_common.c:604
 vsock_assign_transport+0x473/0x5b0 net/vmw_vsock/af_vsock.c:506
 vsock_connect+0x5cf/0xd30 net/vmw_vsock/af_vsock.c:1361
 __sys_connect_file net/socket.c:1996 [inline]
 __sys_connect+0x2c9/0x300 net/socket.c:2013
 __do_sys_connect net/socket.c:2023 [inline]
 __se_sys_connect net/socket.c:2020 [inline]
 __x64_sys_connect+0x7a/0x90 net/socket.c:2020
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

Freed by task 5525:
 kasan_save_stack mm/kasan/common.c:45 [inline]
 kasan_set_track+0x4b/0x70 mm/kasan/common.c:52
 kasan_save_free_info+0x2b/0x40 mm/kasan/generic.c:516
 ____kasan_slab_free+0x131/0x180 mm/kasan/common.c:241
 __kasan_slab_free+0x11/0x20 mm/kasan/common.c:249
 kasan_slab_free include/linux/kasan.h:178 [inline]
 slab_free_hook mm/slub.c:1745 [inline]
 slab_free_freelist_hook mm/slub.c:1771 [inline]
 slab_free mm/slub.c:3684 [inline]
 __kmem_cache_free+0x218/0x3b0 mm/slub.c:3697
 kfree+0x7a/0xf0 mm/slab_common.c:1009
 virtio_transport_destruct+0x3b/0x40 net/vmw_vsock/virtio_transport_common.c:815
 vsock_deassign_transport net/vmw_vsock/af_vsock.c:421 [inline]
 vsock_assign_transport+0x32b/0x5b0 net/vmw_vsock/af_vsock.c:489
 vsock_connect+0x5cf/0xd30 net/vmw_vsock/af_vsock.c:1361
 __sys_connect_file net/socket.c:1996 [inline]
 __sys_connect+0x2c9/0x300 net/socket.c:2013
 __do_sys_connect net/socket.c:2023 [inline]
 __se_sys_connect net/socket.c:2020 [inline]
 __x64_sys_connect+0x7a/0x90 net/socket.c:2020
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

The buggy address belongs to the object at ffff88812648c700
 which belongs to the cache kmalloc-96 of size 96
The buggy address is located 8 bytes inside of
 96-byte region [ffff88812648c700, ffff88812648c760)

The buggy address belongs to the physical page:
page:ffffea0004992300 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x12648c
flags: 0x4000000000000200(slab|zone=1)
raw: 4000000000000200 0000000000000000 dead000000000122 ffff888100042900
raw: 0000000000000000 0000000000200020 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 0, migratetype Unmovable, gfp_mask 0x12cc0(GFP_KERNEL|__GFP_NOWARN|__GFP_NORETRY), pid 5505, tgid 5502 (syz-executor910), ts 37651836797, free_ts 37651758845
 set_page_owner include/linux/page_owner.h:33 [inline]
 post_alloc_hook+0x213/0x220 mm/page_alloc.c:2566
 prep_new_page+0x1b/0x110 mm/page_alloc.c:2573
 get_page_from_freelist+0x27ea/0x2870 mm/page_alloc.c:4397
 __alloc_pages+0x3a1/0x780 mm/page_alloc.c:5684
 alloc_slab_page+0x6c/0xf0
 allocate_slab mm/slub.c:1962 [inline]
 new_slab+0x90/0x3e0 mm/slub.c:2015
 ___slab_alloc+0x6f9/0xb80 mm/slub.c:3203
 __slab_alloc+0x5d/0xa0 mm/slub.c:3302
 slab_alloc_node mm/slub.c:3387 [inline]
 __kmem_cache_alloc_node+0x1af/0x250 mm/slub.c:3460
 kmalloc_trace+0x2a/0xa0 mm/slab_common.c:1047
 kmalloc include/linux/slab.h:553 [inline]
 kzalloc include/linux/slab.h:689 [inline]
 virtio_transport_alloc_pkt+0x6a/0xa10 net/vmw_vsock/virtio_transport_common.c:55
 virtio_transport_send_pkt_info+0x2c8/0x630 net/vmw_vsock/virtio_transport_common.c:231
 virtio_transport_shutdown net/vmw_vsock/virtio_transport_common.c:781 [inline]
 virtio_transport_close net/vmw_vsock/virtio_transport_common.c:961 [inline]
 virtio_transport_release+0x2df/0xc30 net/vmw_vsock/virtio_transport_common.c:984
 __vsock_release+0x86/0x4b0 net/vmw_vsock/af_vsock.c:814
 vsock_release+0x42/0xa0 net/vmw_vsock/af_vsock.c:901
 __sock_release net/socket.c:652 [inline]
 sock_close+0xdf/0x270 net/socket.c:1390
page last free stack trace:
 reset_page_owner include/linux/page_owner.h:26 [inline]
 free_pages_prepare mm/page_alloc.c:1474 [inline]
 free_pcp_prepare mm/page_alloc.c:1548 [inline]
 free_unref_page_prepare+0x83d/0x850 mm/page_alloc.c:3470
 free_unref_page+0xb2/0x5c0 mm/page_alloc.c:3566
 free_the_page mm/page_alloc.c:774 [inline]
 __free_pages+0x61/0xf0 mm/page_alloc.c:5773
 free_pages+0x7c/0x90 mm/page_alloc.c:5784
 _pgd_free arch/x86/mm/pgtable.c:420 [inline]
 pgd_free+0x17d/0x190 arch/x86/mm/pgtable.c:476
 mm_free_pgd kernel/fork.c:833 [inline]
 __mmdrop+0xb0/0x3e0 kernel/fork.c:884
 mmdrop include/linux/sched/mm.h:50 [inline]
 __mmput+0x304/0x310 kernel/fork.c:1309
 mmput+0x56/0x170 kernel/fork.c:1321
 exit_mm kernel/exit.c:566 [inline]
 do_exit+0xb29/0x2b80 kernel/exit.c:862
 do_group_exit+0x21a/0x2d0 kernel/exit.c:1025
 get_signal+0x169d/0x1820 kernel/signal.c:2879
 arch_do_signal_or_restart+0xb0/0x16f0 arch/x86/kernel/signal.c:871
 exit_to_user_mode_loop+0x74/0xa0 kernel/entry/common.c:168
 exit_to_user_mode_prepare+0x5a/0xa0 kernel/entry/common.c:204
 __syscall_exit_to_user_mode_work kernel/entry/common.c:286 [inline]
 syscall_exit_to_user_mode+0x26/0x140 kernel/entry/common.c:297
 do_syscall_64+0x49/0xb0 arch/x86/entry/common.c:87

Memory state around the buggy address:
 ffff88812648c600: fa fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc
 ffff88812648c680: fa fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc
>ffff88812648c700: fa fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc
                      ^
 ffff88812648c780: fa fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc
 ffff88812648c800: fa fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc
==================================================================

Crashes (3):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/04/03 22:58 android14-6.1 af361f9a1066 51c4dcff .config console log report syz C [disk image] [vmlinux] [kernel image] ci2-android-6-1 KASAN: use-after-free Write in virtio_transport_recv_pkt
2024/06/01 21:41 android14-6.1 74c507aab139 3113787f .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-1 KASAN: use-after-free Write in virtio_transport_recv_pkt
2024/04/03 22:29 android14-6.1 af361f9a1066 51c4dcff .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-1 KASAN: use-after-free Write in virtio_transport_recv_pkt
* Struck through repros no longer work on HEAD.