System crash when NULL pointer dereferenced in __disk_get_part() due to use-after-free on gendisk

Issue

• NULL pointer dereference in __disk_get_part() due to use-after-free on gendisk:

BUG: unable to handle kernel NULL pointer dereference at 0000000000000010
PGD 0 P4D 0 
Oops: 0000 [#1] SMP NOPTI
CPU: 43 PID: 1741841 Comm: mount Kdump: loaded Tainted: G        W  OE    --------- -  - 4.18.0-372.9.1.el8.x86_64 #1
Hardware name: Inspur AS13000G6-CGN24/AS13000G6-CGN24, BIOS 5.05.01 2022-05-16
RIP: 0010:__disk_get_part+0xd/0x30
....
Call Trace:
 generic_make_request_checks+0x87/0x530
 ? finish_wait+0x80/0x80
 generic_make_request+0x30/0x350
 ? __switch_to_asm+0x35/0x70
 submit_bio+0x3c/0x160
 ? bio_add_page+0x42/0x50
 _xfs_buf_ioapply+0x2af/0x420 [xfs]
 ? xfs_buf_get_uncached+0x1ad/0x240 [xfs]
 ? xfs_buf_read_uncached+0x99/0x130 [xfs]
 __xfs_buf_submit+0x63/0x1d0 [xfs]
 xfs_buf_read_uncached+0x99/0x130 [xfs]
 ? pcpu_alloc+0x406/0x770
 xfs_readsb+0xcb/0x1b0 [xfs]
 xfs_fs_fill_super+0x199/0x6a0 [xfs]
 ? xfs_mount_free+0x30/0x30 [xfs]
 get_tree_bdev+0x186/0x260
 vfs_get_tree+0x25/0xb0
 do_mount+0x2e2/0x950
 ksys_mount+0xb6/0xd0
 __x64_sys_mount+0x21/0x30
 do_syscall_64+0x5b/0x1a0
 entry_SYSCALL_64_after_hwframe+0x65/0xca
RIP: 0033:0x7fe95763fb0e

• Additionally, a warning was hit in regard to blkdev_put():

WARNING: CPU: 96 PID: 1740565 at fs/block_dev.c:1792 __blkdev_put+0x202/0x210
Modules linked in: ib_core nft_counter nft_compat nf_tables nfnetlink xfs bonding libcrc32c tls sunrpc vfat fat crct10dif_pclmul crc32_pclmul ipmi_si ghash_clmulni_intel ipmi_devintf ipmi_msghandler pcspkr ast drm_vram_helper i2c_algo_bit drm_ttm_helper ttm sg drm_kms_helper syscopyarea sysfillrect sysimgblt fb_sys_fops drm k10temp ip_tables ext4 mbcache jbd2 sd_mod crc32c_intel ice nvme megaraid_sas(OE) ahci libahci nvme_core libata t10_pi ngbe(OE)
CPU: 96 PID: 1740565 Comm: systemd-udevd Kdump: loaded Tainted: G        W  OE    --------- -  - 4.18.0-372.9.1.el8.x86_64 #1
Hardware name: Inspur AS13000G6-CGN24/AS13000G6-CGN24, BIOS 5.05.01 2022-05-16
RIP: 0010:__blkdev_put+0x202/0x210
....
Call Trace:
 blkdev_put+0x4c/0xe0
 blkdev_close+0x21/0x30
 __fput+0xbe/0x250
 task_work_run+0x8a/0xb0
 exit_to_usermode_loop+0xeb/0xf0
 do_syscall_64+0x198/0x1a0
 entry_SYSCALL_64_after_hwframe+0x65/0xca
RIP: 0033:0x7f6d6750b955
....