CVE-2026-68449

Summary

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

ata: sata_dwc_460ex: fix infinite loop in NCQ tag completion bit-scanning

The hand-rolled bit-scanning loop in the NCQ completion path has an infinite loop bug. When tag_mask has only high bits set (e.g. 0x80000000), the inner while loop left-shifts tag_mask until it overflows to 0. At that point !(0 & 1) is always true and 0 <<= 1 stays 0, causing an infinite loop in hardirq context with a spinlock held.

Replace the open-coded bit-scanning with __ffs() which correctly finds the least significant set bit and is bounded by the width of the argument.

Affected Software

VendorProductVersion RangeStatus
LinuxLinux62936009f35a6659cc3ebe0d90c754182d60da73 < 4c6e64cae2b2dab32ad9099faa339f6a72c0ce16affected
LinuxLinux62936009f35a6659cc3ebe0d90c754182d60da73 < 8c5de0d8ab6824cfdadcbbe1be4c6c9d9f4c1f80affected
LinuxLinux62936009f35a6659cc3ebe0d90c754182d60da73 < 1842d45f461a78988254631893329bdf4596e954affected
LinuxLinux62936009f35a6659cc3ebe0d90c754182d60da73 < 29b916d3556bd12a95be7c56ca391b8cd572f8beaffected
LinuxLinux62936009f35a6659cc3ebe0d90c754182d60da73 < c2130f6553f4a5cbdc259de069600117a995f197affected
LinuxLinux2.6.36affected
LinuxLinux0 < 2.6.36unaffected
LinuxLinux6.6.148 <= 6.6.*unaffected
LinuxLinux6.12.101 <= 6.12.*unaffected
LinuxLinux6.18.42 <= 6.18.*unaffected
LinuxLinux7.1.6 <= 7.1.*unaffected
LinuxLinux7.2-rc4 <= *unaffected

Weaknesses

References