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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_cong_queue_updates+0x25d/0x5b0 net/rds/cong.c:226
Read of size 4 at addr ffff880188290144 by task kworker/u4:4/322

CPU: 1 PID: 322 Comm: kworker/u4:4 Not tainted 4.17.0+ #104
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:77 [inline]
 dump_stack+0x1c9/0x2b4 lib/dump_stack.c:113
 print_address_description+0x6c/0x20b mm/kasan/report.c:256
 kasan_report_error mm/kasan/report.c:354 [inline]
 kasan_report.cold.7+0x242/0x2fe mm/kasan/report.c:412
 check_memory_region_inline mm/kasan/kasan.c:260 [inline]
 check_memory_region+0x13e/0x1b0 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_cong_queue_updates+0x25d/0x5b0 net/rds/cong.c:226
 rds_recv_rcvbuf_delta.part.3+0x2b9/0x350 net/rds/recv.c:118
 rds_recv_rcvbuf_delta net/rds/recv.c:377 [inline]
 rds_recv_incoming+0x85a/0x1320 net/rds/recv.c:377
 rds_loop_xmit+0x16a/0x340 net/rds/loop.c:82
 rds_send_xmit+0x1343/0x29c0 net/rds/send.c:355
 rds_send_worker+0x153/0x300 net/rds/threads.c:199
 process_one_work+0xc73/0x1ba0 kernel/workqueue.c:2153
 worker_thread+0x189/0x13c0 kernel/workqueue.c:2296
 kthread+0x345/0x410 kernel/kthread.c:240
 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:412

The buggy address belongs to the page:
page:ffffea000620a400 count:0 mapcount:-128 mapping:0000000000000000 index:0xffff880188290700
flags: 0x2fffc0000000000()
raw: 02fffc0000000000 ffffea0006de7208 ffffea0006cccb08 0000000000000000
raw: ffff880188290700 0000000000000002 00000000ffffff7f 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff880188290000: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff880188290080: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
>ffff880188290100: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
                                           ^
 ffff880188290180: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff880188290200: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
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