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BUG: KASAN: use-after-free in __list_add_valid+0x93/0xa0 lib/list_debug.c:26
Read of size 8 at addr ffff88801fa531e0 by task syz-executor427/5889

CPU: 0 PID: 5889 Comm: syz-executor427 Not tainted 5.11.0-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:79 [inline]
 dump_stack+0x9a/0xcc lib/dump_stack.c:120
 print_address_description.constprop.0.cold+0x5b/0x2f8 mm/kasan/report.c:230
 __kasan_report mm/kasan/report.c:396 [inline]
 kasan_report.cold+0x79/0xd5 mm/kasan/report.c:413
 __list_add_valid+0x93/0xa0 lib/list_debug.c:26
 __list_add include/linux/list.h:67 [inline]
 list_add_tail include/linux/list.h:100 [inline]
 cma_listen_on_all drivers/infiniband/core/cma.c:2549 [inline]
 rdma_listen+0x51c/0xb10 drivers/infiniband/core/cma.c:3721
 ucma_listen+0x11b/0x1a0 drivers/infiniband/core/ucma.c:1102
 ucma_write+0x1aa/0x2b0 drivers/infiniband/core/ucma.c:1732
 vfs_write+0x1c4/0x870 fs/read_write.c:603
 ksys_write+0x171/0x1d0 fs/read_write.c:658
 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x7fc57c77dfa9
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 b1 14 00 00 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 73 01 c3 48 c7 c1 c0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fffbfa07b88 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007fc57c77dfa9
RDX: 0000000000000010 RSI: 0000000020000040 RDI: 0000000000000003
RBP: 0000000000000000 R08: 00007fffbfa07d28 R09: 00007fffbfa07d28
R10: 00007fffbfa07d28 R11: 0000000000000246 R12: 00007fffbfa07b9c
R13: 431bde82d7b634db R14: 0000000000000000 R15: 0000000000000000

Allocated by task 5888:
 kasan_save_stack+0x1b/0x40 mm/kasan/common.c:38
 kasan_set_track mm/kasan/common.c:46 [inline]
 set_alloc_info mm/kasan/common.c:401 [inline]
 ____kasan_kmalloc.constprop.0+0x82/0xa0 mm/kasan/common.c:429
 kmalloc include/linux/slab.h:552 [inline]
 kzalloc include/linux/slab.h:682 [inline]
 __rdma_create_id+0x56/0x500 drivers/infiniband/core/cma.c:838
 rdma_create_user_id+0x75/0xc0 drivers/infiniband/core/cma.c:891
 ucma_create_id+0x117/0x2e0 drivers/infiniband/core/ucma.c:461
 ucma_write+0x1aa/0x2b0 drivers/infiniband/core/ucma.c:1732
 vfs_write+0x1c4/0x870 fs/read_write.c:603
 ksys_write+0x171/0x1d0 fs/read_write.c:658
 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

Freed by task 5888:
 kasan_save_stack+0x1b/0x40 mm/kasan/common.c:38
 kasan_set_track+0x1c/0x30 mm/kasan/common.c:46
 kasan_set_free_info+0x20/0x30 mm/kasan/generic.c:356
 ____kasan_slab_free+0xe1/0x110 mm/kasan/common.c:362
 kasan_slab_free include/linux/kasan.h:192 [inline]
 slab_free_hook mm/slub.c:1547 [inline]
 slab_free_freelist_hook+0x5d/0x150 mm/slub.c:1580
 slab_free mm/slub.c:3143 [inline]
 kfree+0xdb/0x3b0 mm/slub.c:4139
 ucma_close_id drivers/infiniband/core/ucma.c:185 [inline]
 ucma_destroy_private_ctx+0x7df/0xa80 drivers/infiniband/core/ucma.c:576
 ucma_close+0xfc/0x180 drivers/infiniband/core/ucma.c:1797
 __fput+0x204/0x870 fs/file_table.c:280
 task_work_run+0xc0/0x160 kernel/task_work.c:140
 exit_task_work include/linux/task_work.h:30 [inline]
 do_exit+0xa81/0x2570 kernel/exit.c:825
 do_group_exit+0xe7/0x290 kernel/exit.c:922
 __do_sys_exit_group kernel/exit.c:933 [inline]
 __se_sys_exit_group kernel/exit.c:931 [inline]
 __x64_sys_exit_group+0x35/0x40 kernel/exit.c:931
 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

The buggy address belongs to the object at ffff88801fa53000
 which belongs to the cache kmalloc-2k of size 2048
The buggy address is located 480 bytes inside of
 2048-byte region [ffff88801fa53000, ffff88801fa53800)
The buggy address belongs to the page:
page:00000000e6561816 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x1fa50
head:00000000e6561816 order:3 compound_mapcount:0 compound_pincount:0
flags: 0xfff00000010200(slab|head)
raw: 00fff00000010200 ffffea000089e000 0000000300000003 ffff88800f442000
raw: 0000000000000000 0000000080080008 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 3, migratetype Unmovable, gfp_mask 0x1d20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC|__GFP_HARDWALL), pid 8, ts 47725083692
 set_page_owner include/linux/page_owner.h:31 [inline]
 post_alloc_hook+0x144/0x1c0 mm/page_alloc.c:2297
 prep_new_page mm/page_alloc.c:2306 [inline]
 get_page_from_freelist+0x1c6e/0x3f80 mm/page_alloc.c:3945
 __alloc_pages_nodemask+0x2d6/0x730 mm/page_alloc.c:4995
 alloc_pages include/linux/gfp.h:547 [inline]
 alloc_slab_page mm/slub.c:1618 [inline]
 allocate_slab+0x2b6/0x4a0 mm/slub.c:1758
 new_slab mm/slub.c:1821 [inline]
 new_slab_objects mm/slub.c:2578 [inline]
 ___slab_alloc+0x476/0x790 mm/slub.c:2741
 __slab_alloc.constprop.0+0x95/0xe0 mm/slub.c:2781
 slab_alloc_node mm/slub.c:2857 [inline]
 __kmalloc_node_track_caller+0x1ad/0x3f0 mm/slub.c:4510
 __kmalloc_reserve net/core/skbuff.c:142 [inline]
 __alloc_skb+0x7f/0x4e0 net/core/skbuff.c:210
 alloc_skb include/linux/skbuff.h:1099 [inline]
 nlmsg_new include/net/netlink.h:953 [inline]
 rtmsg_ifinfo_build_skb+0x6d/0x160 net/core/rtnetlink.c:3794
 rollback_registered_many+0xcbe/0x1290 net/core/dev.c:9500
 unregister_netdevice_many.part.0+0x10/0x2b0 net/core/dev.c:10736
 ip_tunnel_delete_nets+0x326/0x4d0 net/ipv4/ip_tunnel.c:1114
 cleanup_net+0x423/0x990 net/core/net_namespace.c:604
 process_one_work+0x84c/0x13b0 kernel/workqueue.c:2275
 worker_thread+0x598/0xf80 kernel/workqueue.c:2421
 kthread+0x36f/0x450 kernel/kthread.c:292
page last free stack trace:
 reset_page_owner include/linux/page_owner.h:24 [inline]
 free_pages_prepare mm/page_alloc.c:1271 [inline]
 __free_pages_ok+0x4da/0xed0 mm/page_alloc.c:1536
 unfreeze_partials+0x16c/0x1b0 mm/slub.c:2359
 put_cpu_partial+0x129/0x200 mm/slub.c:2395
 qlink_free mm/kasan/quarantine.c:146 [inline]
 qlist_free_all+0x5a/0xc0 mm/kasan/quarantine.c:165
 quarantine_reduce+0x180/0x200 mm/kasan/quarantine.c:272
 ____kasan_kmalloc.constprop.0+0x98/0xa0 mm/kasan/common.c:412
 kasan_slab_alloc include/linux/kasan.h:209 [inline]
 slab_post_alloc_hook mm/slab.h:512 [inline]
 slab_alloc_node mm/slub.c:2892 [inline]
 kmem_cache_alloc_node+0x1e0/0x470 mm/slub.c:2928
 __alloc_skb+0x42/0x4e0 net/core/skbuff.c:198
 alloc_skb include/linux/skbuff.h:1099 [inline]
 nlmsg_new include/net/netlink.h:953 [inline]
 rtmsg_ifinfo_build_skb+0x6d/0x160 net/core/rtnetlink.c:3794
 rtmsg_ifinfo_event net/core/rtnetlink.c:3830 [inline]
 rtmsg_ifinfo_event net/core/rtnetlink.c:3821 [inline]
 rtmsg_ifinfo+0x5c/0x100 net/core/rtnetlink.c:3839
 dev_close_many+0x27c/0x580 net/core/dev.c:1640
 rollback_registered_many+0x365/0x1290 net/core/dev.c:9473
 unregister_netdevice_many.part.0+0x10/0x2b0 net/core/dev.c:10736
 ip_tunnel_delete_nets+0x326/0x4d0 net/ipv4/ip_tunnel.c:1114
 cleanup_net+0x423/0x990 net/core/net_namespace.c:604
 process_one_work+0x84c/0x13b0 kernel/workqueue.c:2275

Memory state around the buggy address:
 ffff88801fa53080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88801fa53100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff88801fa53180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                                       ^
 ffff88801fa53200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88801fa53280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
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