CVE-2025-40255

net: core: prevent NULL deref in generic_hwtstamp_ioctl_lower()

N/A
Published: December 4, 2025 at 04:08 PM UTC
Updated: October 19, 2026 at 07:10 PM UTC
1 product affected across 1 vendorLinux Kernel

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Severity
N/A
Exploit prediction
EPSS 0.2%

Description

In the Linux kernel, the following vulnerability has been resolved: net: core: prevent NULL deref in generic_hwtstamp_ioctl_lower() The ethtool tsconfig Netlink path can trigger a null pointer dereference. A call chain such as: tsconfig_prepare_data() -> dev_get_hwtstamp_phylib() -> vlan_hwtstamp_get() -> generic_hwtstamp_get_lower() -> generic_hwtstamp_ioctl_lower() results in generic_hwtstamp_ioctl_lower() being called with kernel_cfg->ifr as NULL. The generic_hwtstamp_ioctl_lower() function does not expect a NULL ifr and dereferences it, leading to a system crash. Fix this by adding a NULL check for kernel_cfg->ifr in generic_hwtstamp_ioctl_lower(). If ifr is NULL, return -EINVAL.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

6.146e9e2eed4f39d52edf5fd006409d211facf49f6b
Vendor states this is fixed in 8817f816ae41908e9625c0770c4af0dcdcc01238 (fixed)
Vendor states this is fixed in f796a8dec9beafcc0f6f0d3478ed685a15c5e062 (fixed)
Vendor states this is fixed in 6.14 (unaffected)
Vendor states this is fixed in 6.17.10 (unaffected)
Vendor states this is fixed in 6.18 (unaffected)

Remediation

No guide yet

No remediation guidance has been written for this CVE yet, and no fixed version or vendor advisory is recorded against it.

References (2)

Quick Info

StatusDEFERRED

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