BUG: memory leak
unreferenced object 0xffff88811a6b4800 (size 2048):
  comm "syz-executor.2", pid 7116, jiffies 4295044828 (age 20.830s)
  hex dump (first 32 bytes):
    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
    20 00 00 00 00 01 00 00 00 00 00 00 01 00 00 00   ...............
  backtrace:
    [<000000000ba3fbee>] kmemleak_alloc_recursive include/linux/kmemleak.h:43 [inline]
    [<000000000ba3fbee>] slab_post_alloc_hook mm/slab.h:586 [inline]
    [<000000000ba3fbee>] slab_alloc mm/slab.c:3320 [inline]
    [<000000000ba3fbee>] __do_kmalloc mm/slab.c:3654 [inline]
    [<000000000ba3fbee>] __kmalloc+0x169/0x300 mm/slab.c:3665
    [<00000000211432a2>] kmalloc include/linux/slab.h:561 [inline]
    [<00000000211432a2>] bio_alloc_bioset+0x1b5/0x2c0 block/bio.c:443
    [<00000000b00396b6>] bio_kmalloc include/linux/bio.h:405 [inline]
    [<00000000b00396b6>] bio_copy_user_iov+0x121/0x4d0 block/bio.c:1251
    [<0000000049df9406>] __blk_rq_map_user_iov block/blk-map.c:73 [inline]
    [<0000000049df9406>] blk_rq_map_user_iov+0xc6/0x2b0 block/blk-map.c:142
    [<00000000cb4bebbc>] blk_rq_map_user+0x71/0xb0 block/blk-map.c:172
    [<0000000043392fb2>] sg_start_req drivers/scsi/sg.c:1837 [inline]
    [<0000000043392fb2>] sg_common_write.isra.0+0x6c9/0xaf0 drivers/scsi/sg.c:807
    [<000000000c1805f9>] sg_write.part.0+0x2dc/0x520 drivers/scsi/sg.c:713
    [<000000005dc1ec6b>] sg_write+0x44/0x64 drivers/scsi/sg.c:621
    [<00000000f3d01663>] __vfs_write+0x43/0xa0 fs/read_write.c:494
    [<00000000cacd5fcc>] vfs_write fs/read_write.c:558 [inline]
    [<00000000cacd5fcc>] vfs_write+0xee/0x210 fs/read_write.c:542
    [<00000000af4a3409>] ksys_write+0x7c/0x130 fs/read_write.c:611
    [<00000000f8d7c10a>] __do_sys_write fs/read_write.c:623 [inline]
    [<00000000f8d7c10a>] __se_sys_write fs/read_write.c:620 [inline]
    [<00000000f8d7c10a>] __x64_sys_write+0x1e/0x30 fs/read_write.c:620
    [<000000007a66e1e9>] do_syscall_64+0x73/0x220 arch/x86/entry/common.c:294
    [<00000000e5a28341>] entry_SYSCALL_64_after_hwframe+0x44/0xa9