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BUG: KASAN: use-after-free in atomic_read include/asm-generic/atomic-instrumented.h:26 [inline]
BUG: KASAN: use-after-free in refcount_read include/linux/refcount.h:43 [inline]
BUG: KASAN: use-after-free in check_net include/net/net_namespace.h:254 [inline]
BUG: KASAN: use-after-free in rds_destroy_pending net/rds/rds.h:951 [inline]
BUG: KASAN: use-after-free in rds_cong_queue_updates+0x209/0x4d0 net/rds/cong.c:229
Read of size 4 at addr ffff88806a434184 by task syz-executor.3/27210

CPU: 1 PID: 27210 Comm: syz-executor.3 Not tainted 5.0.0+ #98
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x172/0x1f0 lib/dump_stack.c:113
 print_address_description.cold+0x7c/0x20d mm/kasan/report.c:187
 kasan_report.cold+0x1b/0x40 mm/kasan/report.c:317
 check_memory_region_inline mm/kasan/generic.c:185 [inline]
 check_memory_region+0x123/0x190 mm/kasan/generic.c:191
 kasan_check_read+0x11/0x20 mm/kasan/common.c:102
 atomic_read include/asm-generic/atomic-instrumented.h:26 [inline]
 refcount_read include/linux/refcount.h:43 [inline]
 check_net include/net/net_namespace.h:254 [inline]
 rds_destroy_pending net/rds/rds.h:951 [inline]
 rds_cong_queue_updates+0x209/0x4d0 net/rds/cong.c:229
 rds_recv_rcvbuf_delta.part.0+0x34f/0x3f0 net/rds/recv.c:118
 rds_recv_rcvbuf_delta net/rds/recv.c:379 [inline]
 rds_recv_incoming+0x789/0x11f0 net/rds/recv.c:379
 rds_loop_xmit+0xf3/0x2a0 net/rds/loop.c:96
 rds_send_xmit+0x1113/0x2560 net/rds/send.c:355
 rds_sendmsg+0x3017/0x3550 net/rds/send.c:1369
 sock_sendmsg_nosec net/socket.c:622 [inline]
 sock_sendmsg+0xdd/0x130 net/socket.c:632
 __sys_sendto+0x262/0x380 net/socket.c:1809
 __do_sys_sendto net/socket.c:1821 [inline]
 __se_sys_sendto net/socket.c:1817 [inline]
 __x64_sys_sendto+0xe1/0x1a0 net/socket.c:1817
 do_syscall_64+0x103/0x610 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x458079
Code: ad b8 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 7b b8 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007f87071c1c78 EFLAGS: 00000246 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 0000000000000006 RCX: 0000000000458079
RDX: 0000000000000480 RSI: 0000000020000a00 RDI: 0000000000000003
RBP: 000000000073bf00 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f87071c26d4
R13: 00000000004c56f1 R14: 00000000004d9628 R15: 00000000ffffffff

The buggy address belongs to the page:
page:ffffea0001a90d00 count:0 mapcount:-128 mapping:0000000000000000 index:0xffff88806a434140
flags: 0x1fffc0000000000()
raw: 01fffc0000000000 ffffea0001335c08 ffffea000241a108 0000000000000000
raw: ffff88806a434140 0000000000000002 00000000ffffff7f 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff88806a434080: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff88806a434100: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
>ffff88806a434180: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
                   ^
 ffff88806a434200: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff88806a434280: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
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