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
[<0000000029123163>] kobject_set_name_vargs+0x56/0x150
[<00000000747219c9>] kobject_set_name+0xab/0xe0
[<0000000005f1ea4e>] __class_register+0x15c/0x49a

unreferenced object 0xffff888037274000 (size 1024):
comm "modprobe", pid 502, jiffies 4294906074 (age 49.296s)
hex dump (first 32 bytes):
00 40 27 37 80 88 ff ff 00 40 27 37 80 88 ff ff .@'7.....@'7....
00 00 00 00 ad 4e ad de ff ff ff ff 00 00 00 00 .....N..........
backtrace:
[<00000000151f9600>] kmem_cache_alloc_trace+0x17c/0x2f0
[<00000000ecf3dd95>] __class_register+0x86/0x49a
Advisories

No advisories yet.

Fixes

Solution

No solution given by the vendor.


Workaround

No workaround given by the vendor.

History

Thu, 23 Oct 2025 00:15:00 +0000

Type Values Removed Values Added
References
Metrics threat_severity

None

cvssV3_1

{'score': 5.5, 'vector': 'CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H'}

threat_severity

Low


Wed, 22 Oct 2025 13:45:00 +0000

Type Values Removed Values Added
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 [<0000000029123163>] kobject_set_name_vargs+0x56/0x150 [<00000000747219c9>] kobject_set_name+0xab/0xe0 [<0000000005f1ea4e>] __class_register+0x15c/0x49a unreferenced object 0xffff888037274000 (size 1024): comm "modprobe", pid 502, jiffies 4294906074 (age 49.296s) hex dump (first 32 bytes): 00 40 27 37 80 88 ff ff 00 40 27 37 80 88 ff ff .@'7.....@'7.... 00 00 00 00 ad 4e ad de ff ff ff ff 00 00 00 00 .....N.......... backtrace: [<00000000151f9600>] kmem_cache_alloc_trace+0x17c/0x2f0 [<00000000ecf3dd95>] __class_register+0x86/0x49a
Title class: fix possible memory leak in __class_register()
References

cve-icon MITRE

Status: PUBLISHED

Assigner: Linux

Published:

Updated: 2025-10-22T13:23:31.565Z

Reserved: 2025-10-22T13:20:23.761Z

Link: CVE-2022-50578

cve-icon Vulnrichment

No data.

cve-icon NVD

Status : Awaiting Analysis

Published: 2025-10-22T14:15:42.803

Modified: 2025-10-22T21:12:48.953

Link: CVE-2022-50578

cve-icon Redhat

Severity : Low

Publid Date: 2025-10-22T00:00:00Z

Links: CVE-2022-50578 - Bugzilla

cve-icon OpenCVE Enrichment

No data.