CVE-2026-43245: ntfs: ->d_compare() must not block

Severity: high (CVSS 7.5 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.4% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2026-05-06 · updated 2026-06-17

Description

In the Linux kernel, the following vulnerability has been resolved: ntfs: ->d_compare() must not block ... so don't use __getname() there. Switch it (and ntfs_d_hash(), while we are at it) to kmalloc(PATH_MAX, GFP_NOWAIT). Yes, ntfs_d_hash() almost certainly can do with smaller allocations, but let ntfs folks deal with that - keep the allocation size as-is for now. Stop abusing names_cachep in ntfs, period - various uses of that thing in there have nothing to do with pathnames; just use k[mz]alloc() and be done with that. For now let's keep sizes as-in, but AFAICS none of the users actually want PATH_MAX.

Affected products

Linux kernel: from 6.2 before 6.18.16; from 6.19 before 6.19.6 — fixed in 6.18.16, 6.19.6

How to fix

Upgrade to a fixed version: Linux kernel 6.18.16, 6.19.6. Check the vendor advisory for mitigations.

References

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