BUG: memory leak
unreferenced object 0xffff88811eab6800 (size 2048):
  comm "syz-executor497", pid 7159, jiffies 4295021227 (age 136.510s)
  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 02 01 00 00 00 00 00 00 08 00 00 00   ...............
  backtrace:
    [<000000008416c560>] kmemleak_alloc_recursive include/linux/kmemleak.h:43 [inline]
    [<000000008416c560>] slab_post_alloc_hook mm/slab.h:439 [inline]
    [<000000008416c560>] slab_alloc mm/slab.c:3326 [inline]
    [<000000008416c560>] __do_kmalloc mm/slab.c:3658 [inline]
    [<000000008416c560>] __kmalloc+0x161/0x2c0 mm/slab.c:3669
    [<00000000ded98c76>] kmalloc include/linux/slab.h:552 [inline]
    [<00000000ded98c76>] bio_alloc_bioset+0x1b8/0x2c0 block/bio.c:439
    [<00000000746540c3>] bio_kmalloc include/linux/bio.h:391 [inline]
    [<00000000746540c3>] bio_copy_user_iov+0x113/0x4a0 block/bio.c:1279
    [<00000000f2e8855b>] __blk_rq_map_user_iov block/blk-map.c:67 [inline]
    [<00000000f2e8855b>] blk_rq_map_user_iov+0xc6/0x2b0 block/blk-map.c:136
    [<00000000cc04018d>] blk_rq_map_user+0x71/0xb0 block/blk-map.c:166
    [<0000000028326141>] sg_start_req drivers/scsi/sg.c:1813 [inline]
    [<0000000028326141>] sg_common_write.isra.0+0x619/0xa10 drivers/scsi/sg.c:809
    [<000000009bab9666>] sg_write.part.0+0x325/0x570 drivers/scsi/sg.c:709
    [<0000000011493dc6>] sg_write+0x44/0x64 drivers/scsi/sg.c:617
    [<000000006873bed5>] __vfs_write+0x43/0xa0 fs/read_write.c:494
    [<00000000bd718342>] vfs_write fs/read_write.c:558 [inline]
    [<00000000bd718342>] vfs_write+0xee/0x210 fs/read_write.c:542
    [<00000000b9262598>] ksys_write+0x7c/0x130 fs/read_write.c:611
    [<000000004c09935a>] __do_sys_write fs/read_write.c:623 [inline]
    [<000000004c09935a>] __se_sys_write fs/read_write.c:620 [inline]
    [<000000004c09935a>] __x64_sys_write+0x1e/0x30 fs/read_write.c:620
    [<00000000c1e90ac2>] do_syscall_64+0x76/0x1a0 arch/x86/entry/common.c:301
    [<0000000073ed53a4>] entry_SYSCALL_64_after_hwframe+0x44/0xa9