KASAN: out-of-bounds Read in rds_cong_queue

Kernel	Title	Repro	Cause bisect	Fix bisect	Count	Last	Reported	Patched	Status
upstream	KASAN: out-of-bounds Read in rds_cong_queue_updates (2) rds				3	2145d	2143d	0/26	closed as dup on 2018/06/13 07:52
==================================================================
BUG: KASAN: out-of-bounds in __read_once_size include/linux/compiler.h:188 [inline]
BUG: KASAN: out-of-bounds in atomic_read arch/x86/include/asm/atomic.h:27 [inline]
BUG: KASAN: out-of-bounds in refcount_read include/linux/refcount.h:42 [inline]
BUG: KASAN: out-of-bounds in check_net include/net/net_namespace.h:228 [inline]
BUG: KASAN: out-of-bounds in rds_destroy_pending net/rds/rds.h:868 [inline]
BUG: KASAN: out-of-bounds in rds_cong_queue_updates+0x4d3/0x4f0 net/rds/cong.c:226
Read of size 4 at addr ffff8801b3632104 by task kworker/u4:0/5

CPU: 0 PID: 5 Comm: kworker/u4:0 Not tainted 4.16.0-rc5+ #358
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: krdsd rds_send_worker
Call Trace:
 __dump_stack lib/dump_stack.c:17 [inline]
 dump_stack+0x194/0x24d 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
 __asan_report_load4_noabort+0x14/0x20 mm/kasan/report.c:432
 __read_once_size include/linux/compiler.h:188 [inline]
 atomic_read arch/x86/include/asm/atomic.h:27 [inline]
 refcount_read include/linux/refcount.h:42 [inline]
 check_net include/net/net_namespace.h:228 [inline]
 rds_destroy_pending net/rds/rds.h:868 [inline]
 rds_cong_queue_updates+0x4d3/0x4f0 net/rds/cong.c:226
 rds_recv_rcvbuf_delta.part.2+0x289/0x320 net/rds/recv.c:118
 rds_recv_rcvbuf_delta net/rds/recv.c:377 [inline]
 rds_recv_incoming+0xeb4/0x11d0 net/rds/recv.c:377
 rds_loop_xmit+0x149/0x320 net/rds/loop.c:82
 rds_send_xmit+0xbcd/0x26b0 net/rds/send.c:355
 rds_send_worker+0x115/0x2a0 net/rds/threads.c:199
 process_one_work+0xc47/0x1bb0 kernel/workqueue.c:2113
 worker_thread+0x223/0x1990 kernel/workqueue.c:2247
 kthread+0x33c/0x400 kernel/kthread.c:238
 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:406

The buggy address belongs to the page:
page:ffffea0006cd8c80 count:1 mapcount:0 mapping:0000000000000000 index:0x0
flags: 0x2fffc0000000000()
raw: 02fffc0000000000 0000000000000000 0000000000000000 00000001ffffffff
raw: dead000000000100 dead000000000200 0000000000000000 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff8801b3632000: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff8801b3632080: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffff8801b3632100: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
                      ^
 ffff8801b3632180: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff8801b3632200: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
==================================================================
Kernel panic - not syncing: panic_on_warn set ...

CPU: 0 PID: 5 Comm: kworker/u4:0 Tainted: G    B            4.16.0-rc5+ #358
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: krdsd rds_send_worker
Call Trace:
 __dump_stack lib/dump_stack.c:17 [inline]
 dump_stack+0x194/0x24d lib/dump_stack.c:53
 panic+0x1e4/0x41c kernel/panic.c:183
 kasan_end_report+0x50/0x50 mm/kasan/report.c:180
 kasan_report_error mm/kasan/report.c:359 [inline]
 kasan_report+0x149/0x360 mm/kasan/report.c:412
 __asan_report_load4_noabort+0x14/0x20 mm/kasan/report.c:432
 __read_once_size include/linux/compiler.h:188 [inline]
 atomic_read arch/x86/include/asm/atomic.h:27 [inline]
 refcount_read include/linux/refcount.h:42 [inline]
 check_net include/net/net_namespace.h:228 [inline]
 rds_destroy_pending net/rds/rds.h:868 [inline]
 rds_cong_queue_updates+0x4d3/0x4f0 net/rds/cong.c:226
 rds_recv_rcvbuf_delta.part.2+0x289/0x320 net/rds/recv.c:118
 rds_recv_rcvbuf_delta net/rds/recv.c:377 [inline]
 rds_recv_incoming+0xeb4/0x11d0 net/rds/recv.c:377
 rds_loop_xmit+0x149/0x320 net/rds/loop.c:82
 rds_send_xmit+0xbcd/0x26b0 net/rds/send.c:355
 rds_send_worker+0x115/0x2a0 net/rds/threads.c:199
 process_one_work+0xc47/0x1bb0 kernel/workqueue.c:2113
 worker_thread+0x223/0x1990 kernel/workqueue.c:2247
 kthread+0x33c/0x400 kernel/kthread.c:238
 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:406
Dumping ftrace buffer:
   (ftrace buffer empty)
Kernel Offset: disabled
Rebooting in 86400 seconds..