CVE-2022-50578

/// Technical description

In the Linux kernel, the following vulnerability has been resolved:

class: fix possible memory leak in __class_register()

If class_add_groups() returns error, the 'cp->subsys' need be

unregister, and the 'cp' need be freed.

We can not call kset_unregister() here, because the 'cls' will

be freed in callback function class_release() and it's also

freed in caller's error path, it will cause double free.

So fix this by calling kobject_del() and kfree_const(name) to

cleanup kobject. Besides, call kfree() to free the 'cp'.

Fault injection test can trigger this:

unreferenced object 0xffff888102fa8190 (size 8):

comm "modprobe", pid 502, jiffies 4294906074 (age 49.296s)

hex dump (first 8 bytes):

70 6b 74 63 64 76 64 00 pktcdvd.

backtrace:

[<00000000e7c7703d>] __kmalloc_track_caller+0x1ae/0x320

[<000000005e4d70bc>] kstrdup+0x3a/0x70

[<00000000c2e5e85a>] kstrdup_const+0x68/0x80

[<000000000049a8c7>] kvasprintf_const+0x10b/0x190

[<0000000

/// Remediation

Check the references section for vendor advisories, patches, and mitigation guidance. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.

/// References