vdpa_sim: fix possible memory leak in vdpasim_net_init() and vdpasim_blk_init()

Vulnerability Description

In the Linux kernel, the following vulnerability has been resolved: vdpa_sim: fix possible memory leak in vdpasim_net_init() and vdpasim_blk_init() Inject fault while probing module, if device_register() fails in vdpasim_net_init() or vdpasim_blk_init(), but the refcount of kobject is not decreased to 0, the name allocated in dev_set_name() is leaked. Fix this by calling put_device(), so that name can be freed in callback function kobject_cleanup(). (vdpa_sim_net) unreferenced object 0xffff88807eebc370 (size 16): comm "modprobe", pid 3848, jiffies 4362982860 (age 18.153s) hex dump (first 16 bytes): 76 64 70 61 73 69 6d 5f 6e 65 74 00 6b 6b 6b a5 vdpasim_net.kkk. backtrace: [<ffffffff8174f19e>] __kmalloc_node_track_caller+0x4e/0x150 [<ffffffff81731d53>] kstrdup+0x33/0x60 [<ffffffff83a5d421>] kobject_set_name_vargs+0x41/0x110 [<ffffffff82d87aab>] dev_set_name+0xab/0xe0 [<ffffffff82d91a23>] device_add+0xe3/0x1a80 [<ffffffffa0270013>] 0xffffffffa0270013 [<ffffffff81001c27>] do_one_initcall+0x87/0x2e0 [<ffffffff813739cb>] do_init_module+0x1ab/0x640 [<ffffffff81379d20>] load_module+0x5d00/0x77f0 [<ffffffff8137bc40>] __do_sys_finit_module+0x110/0x1b0 [<ffffffff83c4d505>] do_syscall_64+0x35/0x80 [<ffffffff83e0006a>] entry_SYSCALL_64_after_hwframe+0x46/0xb0 (vdpa_sim_blk) unreferenced object 0xffff8881070c1250 (size 16): comm "modprobe", pid 6844, jiffies 4364069319 (age 17.572s) hex dump (first 16 bytes): 76 64 70 61 73 69 6d 5f 62 6c 6b 00 6b 6b 6b a5 vdpasim_blk.kkk. backtrace: [<ffffffff8174f19e>] __kmalloc_node_track_caller+0x4e/0x150 [<ffffffff81731d53>] kstrdup+0x33/0x60 [<ffffffff83a5d421>] kobject_set_name_vargs+0x41/0x110 [<ffffffff82d87aab>] dev_set_name+0xab/0xe0 [<ffffffff82d91a23>] device_add+0xe3/0x1a80 [<ffffffffa0220013>] 0xffffffffa0220013 [<ffffffff81001c27>] do_one_initcall+0x87/0x2e0 [<ffffffff813739cb>] do_init_module+0x1ab/0x640 [<ffffffff81379d20>] load_module+0x5d00/0x77f0 [<ffffffff8137bc40>] __do_sys_finit_module+0x110/0x1b0 [<ffffffff83c4d505>] do_syscall_64+0x35/0x80 [<ffffffff83e0006a>] entry_SYSCALL_64_after_hwframe+0x46/0xb0

References

• https://git.kernel.org/stable/c/586e6fd7d581f987f7d0d2592edf0b26397e783e
• https://git.kernel.org/stable/c/5be953e353fe421f2983e1fd37f07fba97edbffc
• https://git.kernel.org/stable/c/337c24d817e28dd454ca22f1063dfad20822426e
• https://git.kernel.org/stable/c/aeca7ff254843d49a8739f07f7dab1341450111d