syzbot


KASAN: use-after-free Read in rds_queue_reconnect

Status: closed as dup on 2018/03/07 13:54
Subsystems: rds
[Documentation on labels]
Reported-by: syzbot+0c23175ed0545d7d8c52@syzkaller.appspotmail.com
First crash: 2280d, last: 2251d
Duplicate of
Title Repro Cause bisect Fix bisect Count Last Reported
KASAN: use-after-free Read in rds_cong_queue_updates rds C 18168 2161d 2292d

Sample crash report:
QAT: Invalid ioctl
QAT: Invalid ioctl
bond0 (unregistering): Released all slaves
==================================================================
BUG: KASAN: use-after-free in atomic_read include/asm-generic/atomic-instrumented.h:21 [inline]
BUG: KASAN: use-after-free in refcount_read include/linux/refcount.h:42 [inline]
BUG: KASAN: use-after-free in check_net include/net/net_namespace.h:236 [inline]
BUG: KASAN: use-after-free in rds_destroy_pending net/rds/rds.h:897 [inline]
BUG: KASAN: use-after-free in rds_queue_reconnect+0x434/0x990 net/rds/threads.c:152
Read of size 4 at addr ffff8801911ec044 by task kworker/u4:0/6

CPU: 0 PID: 6 Comm: kworker/u4:0 Not tainted 4.16.0+ #15
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: krdsd rds_connect_worker
Call Trace:
 __dump_stack lib/dump_stack.c:17 [inline]
 dump_stack+0x1a7/0x27d lib/dump_stack.c:53
 print_address_description+0x73/0x250 mm/kasan/report.c:256
 kasan_report_error mm/kasan/report.c:354 [inline]
 kasan_report+0x23c/0x360 mm/kasan/report.c:412
 check_memory_region_inline mm/kasan/kasan.c:260 [inline]
 check_memory_region+0x137/0x190 mm/kasan/kasan.c:267
 kasan_check_read+0x11/0x20 mm/kasan/kasan.c:272
 atomic_read include/asm-generic/atomic-instrumented.h:21 [inline]
 refcount_read include/linux/refcount.h:42 [inline]
 check_net include/net/net_namespace.h:236 [inline]
 rds_destroy_pending net/rds/rds.h:897 [inline]
 rds_queue_reconnect+0x434/0x990 net/rds/threads.c:152
 rds_connect_worker+0x1cd/0x210 net/rds/threads.c:183
 process_one_work+0xc97/0x1c40 kernel/workqueue.c:2145
 worker_thread+0x1c3/0x1380 kernel/workqueue.c:2279
 kthread+0x33c/0x400 kernel/kthread.c:238
 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:411

Allocated by task 4525:
 save_stack+0x43/0xd0 mm/kasan/kasan.c:447
 set_track mm/kasan/kasan.c:459 [inline]
 kasan_kmalloc+0xad/0xe0 mm/kasan/kasan.c:552
 kasan_slab_alloc+0x12/0x20 mm/kasan/kasan.c:489
 kmem_cache_alloc+0x12e/0x760 mm/slab.c:3542
 kmem_cache_zalloc include/linux/slab.h:691 [inline]
 net_alloc net/core/net_namespace.c:383 [inline]
 copy_net_ns+0x152/0x480 net/core/net_namespace.c:423
 create_new_namespaces+0x432/0x890 kernel/nsproxy.c:107
 unshare_nsproxy_namespaces+0xae/0x1e0 kernel/nsproxy.c:206
 ksys_unshare+0x68a/0xe90 kernel/fork.c:2407
 SYSC_unshare kernel/fork.c:2475 [inline]
 SyS_unshare+0x15/0x20 kernel/fork.c:2473
 do_syscall_64+0x281/0x940 arch/x86/entry/common.c:287
 entry_SYSCALL_64_after_hwframe+0x42/0xb7

Freed by task 6:
 save_stack+0x43/0xd0 mm/kasan/kasan.c:447
 set_track mm/kasan/kasan.c:459 [inline]
 __kasan_slab_free+0x11a/0x170 mm/kasan/kasan.c:520
 kasan_slab_free+0xe/0x10 mm/kasan/kasan.c:527
 __cache_free mm/slab.c:3486 [inline]
 kmem_cache_free+0x83/0x2a0 mm/slab.c:3744
 net_free net/core/net_namespace.c:399 [inline]
 net_drop_ns.part.13+0x10c/0x130 net/core/net_namespace.c:406
 net_drop_ns net/core/net_namespace.c:405 [inline]
 cleanup_net+0x7a6/0xaa0 net/core/net_namespace.c:541
 process_one_work+0xc97/0x1c40 kernel/workqueue.c:2145
 worker_thread+0x1c3/0x1380 kernel/workqueue.c:2279
 kthread+0x33c/0x400 kernel/kthread.c:238
 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:411

The buggy address belongs to the object at ffff8801911ec040
 which belongs to the cache net_namespace of size 8768
The buggy address is located 4 bytes inside of
 8768-byte region [ffff8801911ec040, ffff8801911ee280)
The buggy address belongs to the page:
page:ffffea0006447b00 count:1 mapcount:0 mapping:ffff8801911ec040 index:0x0 compound_mapcount: 0
flags: 0x2fffc0000008100(slab|head)
raw: 02fffc0000008100 ffff8801911ec040 0000000000000000 0000000100000001
raw: ffff8801d9fab548 ffffea00063d0820 ffff8801d9fbfe00 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff8801911ebf00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff8801911ebf80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff8801911ec000: fc fc fc fc fc fc fc fc fb fb fb fb fb fb fb fb
                                           ^
 ffff8801911ec080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff8801911ec100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================

Crashes (19):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2018/04/05 00:21 upstream 3e968c9f1401 676bd07e .config console log report ci-upstream-kasan-gce-root
2018/04/03 06:06 upstream 86bbbebac193 676bd07e .config console log report ci-upstream-kasan-gce-root
2018/04/01 01:18 upstream 10b84daddbec 0174c6c8 .config console log report ci-upstream-kasan-gce-root
2018/03/30 14:06 upstream c2a9838452a4 d47f0ed6 .config console log report ci-upstream-kasan-gce
2018/03/30 10:05 upstream c2a9838452a4 d47f0ed6 .config console log report ci-upstream-kasan-gce
2018/03/29 22:50 upstream 0b412605ef5f d47f0ed6 .config console log report ci-upstream-kasan-gce
2018/03/15 05:49 upstream 3032f8c504d2 08dacaa0 .config console log report ci-upstream-kasan-gce
2018/03/15 00:50 upstream 3032f8c504d2 08dacaa0 .config console log report ci-upstream-kasan-gce
2018/03/12 22:28 upstream 0c8efd610b58 f505ca4b .config console log report ci-upstream-kasan-gce
2018/03/07 21:43 upstream 86f84779d8e9 a5e76540 .config console log report ci-upstream-kasan-gce
2018/03/07 03:11 upstream ce380619fab9 c8a18476 .config console log report ci-upstream-kasan-gce
2018/04/04 19:13 upstream f2d285669aae 676bd07e .config console log report ci-upstream-kasan-gce-386
2018/03/28 22:15 upstream 3eb2ce825ea1 bf5e585c .config console log report ci-upstream-kasan-gce-386
2018/03/27 22:51 upstream 3eb2ce825ea1 bf5e585c .config console log report ci-upstream-kasan-gce-386
2018/03/27 15:27 upstream 3eb2ce825ea1 bf5e585c .config console log report ci-upstream-kasan-gce-386
2018/03/18 15:56 upstream 8f5fd927c3a7 08dacaa0 .config console log report ci-upstream-kasan-gce-386
2018/03/17 12:40 upstream 8f5fd927c3a7 08dacaa0 .config console log report ci-upstream-kasan-gce-386
2018/03/16 03:16 upstream e2c15aff5f35 08dacaa0 .config console log report ci-upstream-kasan-gce-386
2018/03/10 19:17 upstream cdb06e9d8f52 36d1c454 .config console log report ci-upstream-kasan-gce-386
* Struck through repros no longer work on HEAD.