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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: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 ffff88806ee3c144 by task syz-executor.5/11550

CPU: 1 PID: 11550 Comm: syz-executor.5 Not tainted 5.0.0+ #97
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: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+0x29b4/0x3540 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: 0033:0x457f29
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:00007fe24ebc0c78 EFLAGS: 00000246 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 0000000000000006 RCX: 0000000000457f29
RDX: 0000000000000480 RSI: 0000000020000a00 RDI: 0000000000000003
RBP: 000000000073bf00 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007fe24ebc16d4
R13: 00000000004c5651 R14: 00000000004d9588 R15: 00000000ffffffff

Allocated by task 7661:
 save_stack+0x45/0xd0 mm/kasan/common.c:73
 set_track mm/kasan/common.c:85 [inline]
 __kasan_kmalloc mm/kasan/common.c:495 [inline]
 __kasan_kmalloc.constprop.0+0xcf/0xe0 mm/kasan/common.c:468
 kasan_slab_alloc+0xf/0x20 mm/kasan/common.c:503
 slab_post_alloc_hook mm/slab.h:440 [inline]
 slab_alloc mm/slab.c:3388 [inline]
 kmem_cache_alloc+0x11a/0x6f0 mm/slab.c:3548
 kmem_cache_zalloc include/linux/slab.h:730 [inline]
 net_alloc net/core/net_namespace.c:384 [inline]
 copy_net_ns+0xed/0x340 net/core/net_namespace.c:424
 create_new_namespaces+0x400/0x7b0 kernel/nsproxy.c:107
 unshare_nsproxy_namespaces+0xc2/0x200 kernel/nsproxy.c:206
 ksys_unshare+0x440/0x980 kernel/fork.c:2550
 __do_sys_unshare kernel/fork.c:2618 [inline]
 __se_sys_unshare kernel/fork.c:2616 [inline]
 __x64_sys_unshare+0x31/0x40 kernel/fork.c:2616
 do_syscall_64+0x103/0x610 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x49/0xbe

Freed by task 14474:
 save_stack+0x45/0xd0 mm/kasan/common.c:73
 set_track mm/kasan/common.c:85 [inline]
 __kasan_slab_free+0x102/0x150 mm/kasan/common.c:457
 kasan_slab_free+0xe/0x10 mm/kasan/common.c:465
 __cache_free mm/slab.c:3494 [inline]
 kmem_cache_free+0x86/0x260 mm/slab.c:3754
 net_free net/core/net_namespace.c:400 [inline]
 net_drop_ns.part.0+0x70/0x90 net/core/net_namespace.c:407
 net_drop_ns net/core/net_namespace.c:406 [inline]
 cleanup_net+0x538/0x960 net/core/net_namespace.c:569
 process_one_work+0x98e/0x1790 kernel/workqueue.c:2173
 worker_thread+0x98/0xe40 kernel/workqueue.c:2319
 kthread+0x357/0x430 kernel/kthread.c:246
 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:352

The buggy address belongs to the object at ffff88806ee3c140
 which belongs to the cache net_namespace of size 8512
The buggy address is located 4 bytes inside of
 8512-byte region [ffff88806ee3c140, ffff88806ee3e280)
The buggy address belongs to the page:
page:ffffea0001bb8f00 count:1 mapcount:0 mapping:ffff88821bc45e00 index:0x0 compound_mapcount: 0
flags: 0x1fffc0000010200(slab|head)
raw: 01fffc0000010200 ffffea00023d2f08 ffffea0002155408 ffff88821bc45e00
raw: 0000000000000000 ffff88806ee3c140 0000000100000001 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff88806ee3c000: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff88806ee3c080: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff88806ee3c100: fc fc fc fc fc fc fc fc fb fb fb fb fb fb fb fb
                                           ^
 ffff88806ee3c180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88806ee3c200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
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