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executing program
BUG: memory leak
unreferenced object 0xffff8881171d1600 (size 256):
  comm "softirq", pid 0, jiffies 4294942390 (age 7.930s)
  hex dump (first 32 bytes):
    00 01 00 00 00 00 ad de 00 02 00 00 00 00 ad de  ................
    00 20 2c 1f 81 88 ff ff 00 00 00 00 00 00 00 00  . ,.............
  backtrace:
    [<0000000082963841>] kmemleak_alloc_recursive include/linux/kmemleak.h:43 [inline]
    [<0000000082963841>] slab_post_alloc_hook mm/slab.h:439 [inline]
    [<0000000082963841>] slab_alloc mm/slab.c:3326 [inline]
    [<0000000082963841>] kmem_cache_alloc_trace+0x13d/0x280 mm/slab.c:3553
    [<0000000054eab101>] kmalloc include/linux/slab.h:547 [inline]
    [<0000000054eab101>] kzalloc include/linux/slab.h:742 [inline]
    [<0000000054eab101>] lapb_create_cb net/lapb/lapb_iface.c:116 [inline]
    [<0000000054eab101>] lapb_register+0x90/0x1c0 net/lapb/lapb_iface.c:153
    [<000000005e4be75d>] x25_asy_open drivers/net/wan/x25_asy.c:483 [inline]
    [<000000005e4be75d>] x25_asy_open_tty+0x26b/0x2f6 drivers/net/wan/x25_asy.c:573
    [<00000000a1955d0d>] tty_ldisc_open.isra.0+0x40/0x70 drivers/tty/tty_ldisc.c:469
    [<00000000c1fd4b60>] tty_set_ldisc+0x149/0x240 drivers/tty/tty_ldisc.c:596
    [<000000001fcd470c>] tiocsetd drivers/tty/tty_io.c:2332 [inline]
    [<000000001fcd470c>] tty_ioctl+0x366/0xa30 drivers/tty/tty_io.c:2592
    [<00000000235046e7>] vfs_ioctl fs/ioctl.c:46 [inline]
    [<00000000235046e7>] file_ioctl fs/ioctl.c:509 [inline]
    [<00000000235046e7>] do_vfs_ioctl+0x62a/0x810 fs/ioctl.c:696
    [<00000000a7aeefa2>] ksys_ioctl+0x86/0xb0 fs/ioctl.c:713
    [<0000000058c53352>] __do_sys_ioctl fs/ioctl.c:720 [inline]
    [<0000000058c53352>] __se_sys_ioctl fs/ioctl.c:718 [inline]
    [<0000000058c53352>] __x64_sys_ioctl+0x1e/0x30 fs/ioctl.c:718
    [<0000000012af6732>] do_syscall_64+0x76/0x1a0 arch/x86/entry/common.c:301
    [<0000000011b03c2e>] entry_SYSCALL_64_after_hwframe+0x44/0xa9