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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:43 [inline]
BUG: KASAN: use-after-free in check_net include/net/net_namespace.h:250 [inline]
BUG: KASAN: use-after-free in rds_destroy_pending net/rds/rds.h:941 [inline]
BUG: KASAN: use-after-free in rds_cong_queue_updates+0x1ff/0x4c0 net/rds/cong.c:229
Read of size 4 at addr ffff88804a50c9c4 by task syz-executor.3/21253

CPU: 1 PID: 21253 Comm: syz-executor.3 Not tainted 5.0.0-rc8+ #89
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:100
 atomic_read include/asm-generic/atomic-instrumented.h:21 [inline]
 refcount_read include/linux/refcount.h:43 [inline]
 check_net include/net/net_namespace.h:250 [inline]
 rds_destroy_pending net/rds/rds.h:941 [inline]
 rds_cong_queue_updates+0x1ff/0x4c0 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+0x280a/0x3450 net/rds/send.c:1368
 sock_sendmsg_nosec net/socket.c:621 [inline]
 sock_sendmsg+0xdd/0x130 net/socket.c:631
 __sys_sendto+0x262/0x380 net/socket.c:1786
 __do_sys_sendto net/socket.c:1798 [inline]
 __se_sys_sendto net/socket.c:1794 [inline]
 __ia32_sys_sendto+0xdf/0x1a0 net/socket.c:1794
 do_syscall_32_irqs_on arch/x86/entry/common.c:326 [inline]
 do_fast_syscall_32+0x281/0xc98 arch/x86/entry/common.c:397
 entry_SYSENTER_compat+0x70/0x7f arch/x86/entry/entry_64_compat.S:139
RIP: 0023:0xf7f32869
Code: 85 d2 74 02 89 0a 5b 5d c3 8b 04 24 c3 8b 14 24 c3 8b 3c 24 c3 90 90 90 90 90 90 90 90 90 90 90 90 51 52 55 89 e5 0f 34 cd 80 <5d> 5a 59 c3 90 90 90 90 eb 0d 90 90 90 90 90 90 90 90 90 90 90 90
RSP: 002b:00000000f5d2e0cc EFLAGS: 00000296 ORIG_RAX: 0000000000000171
RAX: ffffffffffffffda RBX: 0000000000000004 RCX: 0000000020000a00
RDX: 0000000000000481 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000

The buggy address belongs to the page:
page:ffffea0001294300 count:0 mapcount:0 mapping:0000000000000000 index:0xffff88804a50c9c0
flags: 0x1fffc0000000000()
raw: 01fffc0000000000 dead000000000100 dead000000000200 0000000000000000
raw: ffff88804a50c9c0 ffff88804a50c9c0 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff88804a50c880: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff88804a50c900: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
>ffff88804a50c980: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
                                           ^
 ffff88804a50ca00: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff88804a50ca80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
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