CVE-2021-47455 ptp: Fix possible memory leak in ptp_clock_register()
A memory leak in the Linux kernel PTP driver allows attackers to cause denial of service by triggering error paths that fail to free allocated memory.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2021-47455?
CVE-2021-47455 is a medium-severity memory corruption vulnerability in Linux kernel, published on 22 May 2024. It can only be exploited from the same machine or local network, with no action from the victim.
Official description
In the Linux kernel, the following vulnerability has been resolved:
ptp: Fix possible memory leak in ptp_clock_register()
I got memory leak as follows when doing fault injection test:
unreferenced object 0xffff88800906c618 (size 8): comm "i2c-idt82p33931", pid 4421, jiffies 4294948083 (age 13.188s) hex dump (first 8 bytes): 70 74 70 30 00 00 00 00 ptp0.... backtrace: [<00000000312ed458>] __kmalloc_track_caller+0x19f/0x3a0 [<0000000079f6e2ff>] kvasprintf+0xb5/0x150 [<0000000026aae54f>] kvasprintf_const+0x60/0x190 [<00000000f323a5f7>] kobject_set_name_vargs+0x56/0x150 [<000000004e35abdd>] dev_set_name+0xc0/0x100 [<00000000f20cfe25>] ptp_clock_register+0x9f4/0xd30 [ptp] [<000000008bb9f0de>] idt82p33_probe.cold+0x8b6/0x1561 [ptp_idt82p33]
When posix_clock_register() returns an error, the name allocated in dev_set_name() will be leaked, the put_device() should be used to give up the device reference, then the name will be freed in kobject_cleanup() and other memory will be freed in ptp_clock_release().
Weakness: CWE-401
Which versions are affected by CVE-2021-47455?
It affects 1 product.
Products include Linux kernel.
How do I fix CVE-2021-47455?
Apply the vendor's patch.
Upgrade to the fixed version. Memory-safe languages, compiler hardening and fuzzing prevent most new cases. More about Memory corruption.
Is CVE-2021-47455 being exploited?
There is no known exploitation of CVE-2021-47455 in the wild and no public exploit code.
Other vulnerabilities in Linux kernel
Sources
Also known as DEBIAN-CVE-2021-47455, GHSA-2r2x-3jh4-chhv, ROOT-OS-DEBIAN-11-CVE-2021-47455, UBUNTU-CVE-2021-47455.