block: fix mismatch size for flush_rq

hulk inclusion
category: bugfix
bugzilla: https://gitee.com/openeuler/intel-kernel/issues/I5HEZ8


CVE: NA

--------------------------------

commit 5c250d55 ("blk-mq: fix kabi broken in struct request")
intrudoce 'struct request_wrapper' to fix kabi broken in 'struct request',
it requires to allocate more size for 'struct request'. However, flush_rq
is missed for such adaptation, which will lead to following
slab-out-of-bounds:

==================================================================
BUG: KASAN: slab-out-of-bounds in sg_init_table+0x23/0x40
Write of size 4096 at addr ffff88812249a148 by task swapper/0/1

Call Trace:
 dump_stack+0xbe/0xf9
 ? sg_init_table+0x23/0x40
 print_address_description.constprop.0+0x1e/0x220
 ? _raw_spin_lock_irqsave+0x80/0xe0
 ? _raw_write_unlock_irqrestore+0x20/0x20
 ? blk_alloc_flush_queue+0xd3/0x1a0
 ? sg_init_table+0x23/0x40
 ? sg_init_table+0x23/0x40
 kasan_report.cold+0x67/0x7f
 ? sg_init_table+0x23/0x40
 check_memory_region+0x17c/0x1e0
 memset+0x20/0x40
 sg_init_table+0x23/0x40
 virtblk_init_request+0x3d/0x50
 ? virtblk_map_queues+0x40/0x40
 blk_mq_realloc_hw_ctxs+0x44d/0xb50
 blk_mq_init_allocated_queue+0x20f/0x980
 ? blk_set_default_limits+0x1ac/0x1c0
 ? blk_alloc_queue+0x3f0/0x410
 blk_mq_init_queue_data+0x58/0xa0
 virtblk_probe+0x51b/0xee0
 ? cache_type_store+0x1a0/0x1a0
 ? __sanitizer_cov_trace_switch+0x50/0x90
 ? ioread8+0x89/0xa0
 virtio_dev_probe+0x449/0x5d0
 ? virtio_features_ok.part.0+0xb0/0xb0
 really_probe+0x26d/0x8a0
 driver_probe_device+0xef/0x280
 device_driver_attach+0xaf/0xc0
 __driver_attach+0x158/0x280
 ? device_driver_attach+0xc0/0xc0
 bus_for_each_dev+0x111/0x180
 ? subsys_dev_iter_exit+0x20/0x20
 ? bus_add_driver+0xb6/0x3e0
 ? klist_node_init+0x7c/0xb0
 bus_add_driver+0x336/0x3e0
 driver_register+0x105/0x1a0
 ? nbd_init+0x273/0x273
 init+0x69/0xad
 do_one_initcall+0xcb/0x370
 ? initcall_blacklisted+0x1b0/0x1b0
 ? parameq+0x110/0x110
 ? __kasan_kmalloc.constprop.0+0xc2/0xd0
 ? kasan_unpoison_shadow+0x33/0x40
 do_initcalls+0x223/0x265
 kernel_init_freeable+0x2bb/0x302
 ? rest_init+0xea/0xea
 kernel_init+0x13/0x1f6
 ? rest_init+0xea/0xea
 ret_from_fork+0x22/0x30

Allocated by task 1:
 kasan_save_stack+0x1b/0x40
 __kasan_kmalloc.constprop.0+0xc2/0xd0
 blk_alloc_flush_queue+0xd3/0x1a0
 blk_mq_realloc_hw_ctxs+0x9fa/0xb50
 blk_mq_init_allocated_queue+0x20f/0x980
 blk_mq_init_queue_data+0x58/0xa0
 virtblk_probe+0x51b/0xee0
 virtio_dev_probe+0x449/0x5d0
 really_probe+0x26d/0x8a0
 driver_probe_device+0xef/0x280
 device_driver_attach+0xaf/0xc0
 __driver_attach+0x158/0x280
 bus_for_each_dev+0x111/0x180
 bus_add_driver+0x336/0x3e0
 driver_register+0x105/0x1a0
 init+0x69/0xad
 do_one_initcall+0xcb/0x370
 do_initcalls+0x223/0x265
 kernel_init_freeable+0x2bb/0x302
 kernel_init+0x13/0x1f6
 ret_from_fork+0x22/0x30

Fixes: 5c250d55 ("blk-mq: fix kabi broken in struct request")
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Reviewed-by: Jason Yan <yanaijie@huawei.com>
Signed-off-by: Zheng Zengkai <zhengzengkai@huawei.com>