syzbot


KASAN: use-after-free Read in rds_tcp_dev_event

Status: auto-closed as invalid on 2020/04/20 07:50
Reported-by: syzbot+ed993c444c4e6193342b@syzkaller.appspotmail.com
First crash: 928d, last: 928d
similar bugs (2):
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-4.14 KASAN: use-after-free Read in rds_tcp_dev_event (2) 1 719d 719d 0/1 auto-closed as invalid on 2020/11/15 00:12
upstream KASAN: use-after-free Read in rds_tcp_dev_event 1 1709d 1702d 4/22 fixed on 2018/02/14 17:41

Sample crash report:
Unknown ioctl -1066647260
IPVS: ftp: loaded support on port[0] = 21
==================================================================
BUG: KASAN: use-after-free in rds_tcp_kill_sock net/rds/tcp.c:531 [inline]
BUG: KASAN: use-after-free in rds_tcp_dev_event+0x924/0xa60 net/rds/tcp.c:573
Read of size 8 at addr ffff88804951ca00 by task kworker/u4:1/22

CPU: 1 PID: 22 Comm: kworker/u4:1 Not tainted 4.14.160-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: netns cleanup_net
Call Trace:
 __dump_stack lib/dump_stack.c:17 [inline]
 dump_stack+0x142/0x197 lib/dump_stack.c:58
 print_address_description.cold+0x7c/0x1dc mm/kasan/report.c:252
 kasan_report_error mm/kasan/report.c:351 [inline]
 kasan_report mm/kasan/report.c:409 [inline]
 kasan_report.cold+0xa9/0x2af mm/kasan/report.c:393
 __asan_report_load8_noabort+0x14/0x20 mm/kasan/report.c:430
 rds_tcp_kill_sock net/rds/tcp.c:531 [inline]
 rds_tcp_dev_event+0x924/0xa60 net/rds/tcp.c:573
 notifier_call_chain+0x111/0x1b0 kernel/notifier.c:93
 __raw_notifier_call_chain kernel/notifier.c:394 [inline]
 raw_notifier_call_chain+0x2e/0x40 kernel/notifier.c:401
 call_netdevice_notifiers_info+0x56/0x70 net/core/dev.c:1671
 call_netdevice_notifiers net/core/dev.c:1687 [inline]
 netdev_run_todo+0x20a/0x770 net/core/dev.c:7910
 rtnl_unlock+0xe/0x10 net/core/rtnetlink.c:106
 default_device_exit_batch+0x328/0x3d0 net/core/dev.c:8730
 ops_exit_list.isra.0+0xfc/0x150 net/core/net_namespace.c:145
 cleanup_net+0x3ba/0x870 net/core/net_namespace.c:484
 process_one_work+0x863/0x1600 kernel/workqueue.c:2114
 worker_thread+0x5d9/0x1050 kernel/workqueue.c:2248
 kthread+0x319/0x430 kernel/kthread.c:232
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:404

Allocated by task 16759:
 save_stack_trace+0x16/0x20 arch/x86/kernel/stacktrace.c:59
 save_stack+0x45/0xd0 mm/kasan/kasan.c:447
 set_track mm/kasan/kasan.c:459 [inline]
 kasan_kmalloc mm/kasan/kasan.c:551 [inline]
 kasan_kmalloc+0xce/0xf0 mm/kasan/kasan.c:529
 __do_kmalloc mm/slab.c:3720 [inline]
 __kmalloc+0x15d/0x7a0 mm/slab.c:3729
 kmalloc_array include/linux/slab.h:607 [inline]
 kcalloc include/linux/slab.h:618 [inline]
 __rds_conn_create+0x43d/0x1760 net/rds/connection.c:176
 rds_conn_create_outgoing+0x3b/0x50 net/rds/connection.c:303
 rds_sendmsg+0xa90/0x1db0 net/rds/send.c:1120
 sock_sendmsg_nosec net/socket.c:646 [inline]
 sock_sendmsg+0xce/0x110 net/socket.c:656
 SYSC_sendto+0x206/0x310 net/socket.c:1763
 SyS_sendto+0x40/0x50 net/socket.c:1731
 do_syscall_64+0x1e8/0x640 arch/x86/entry/common.c:292
 entry_SYSCALL_64_after_hwframe+0x42/0xb7

Freed by task 16759:
 save_stack_trace+0x16/0x20 arch/x86/kernel/stacktrace.c:59
 save_stack+0x45/0xd0 mm/kasan/kasan.c:447
 set_track mm/kasan/kasan.c:459 [inline]
 kasan_slab_free+0x75/0xc0 mm/kasan/kasan.c:524
 __cache_free mm/slab.c:3496 [inline]
 kfree+0xcc/0x270 mm/slab.c:3815
 __rds_conn_create+0xecd/0x1760 net/rds/connection.c:225
 rds_conn_create_outgoing+0x3b/0x50 net/rds/connection.c:303
 rds_sendmsg+0xa90/0x1db0 net/rds/send.c:1120
 sock_sendmsg_nosec net/socket.c:646 [inline]
 sock_sendmsg+0xce/0x110 net/socket.c:656
 SYSC_sendto+0x206/0x310 net/socket.c:1763
 SyS_sendto+0x40/0x50 net/socket.c:1731
 do_syscall_64+0x1e8/0x640 arch/x86/entry/common.c:292
 entry_SYSCALL_64_after_hwframe+0x42/0xb7

The buggy address belongs to the object at ffff88804951ca00
 which belongs to the cache kmalloc-8192 of size 8192
The buggy address is located 0 bytes inside of
 8192-byte region [ffff88804951ca00, ffff88804951ea00)
The buggy address belongs to the page:
page:ffffea0001254700 count:1 mapcount:0 mapping:ffff88804951ca00 index:0x0 compound_mapcount: 0
flags: 0xfffe0000008100(slab|head)
raw: 00fffe0000008100 ffff88804951ca00 0000000000000000 0000000100000001
raw: ffffea0001c94720 ffffea000119b120 ffff8880aa802080 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff88804951c900: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff88804951c980: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff88804951ca00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                   ^
 ffff88804951ca80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88804951cb00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================

Crashes (1):
Manager Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Title
ci2-linux-4-14 2019/12/22 07:49 linux-4.14.y e1f7d50ae3a3 bc586918 .config log report