CVE-2026-80554

Summary

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

s390/vfio_ccw: Limit the number of channel program segments

The processing of channel programs, and the CCWs within them, is done recursively. As such, there is an arbitrary (but not architectural) limit to the number of CCWs that can exist in a single channel program.

The vfio-ccw logic breaks these channel programs into segments whenever it encounters a Transfer-In-Channel (TIC) CCW, and the combined number of segments count towards the global limit. Impose an equivalent limit to the number of segments until such logic can be made non-recursive.

Affected Software

VendorProductVersion RangeStatus
LinuxLinux0a19e61e6d4c6192077ead760ba0a2d350987d4c < 15fb4559a7fdf0b8725e433a71cfd03a1313a48baffected
LinuxLinux0a19e61e6d4c6192077ead760ba0a2d350987d4c < a1625f66eaa1200068a0e2c05bc90e65182fc4e3affected
LinuxLinux0a19e61e6d4c6192077ead760ba0a2d350987d4c < 06f4d6e5a8af6c2072e8cd39dbc512c683ca7fb2affected
LinuxLinux0a19e61e6d4c6192077ead760ba0a2d350987d4c < 4ee94790490ae8dcc97df8597f07836c8a81bbcfaffected
LinuxLinux0a19e61e6d4c6192077ead760ba0a2d350987d4c < 5405c90d6a47b3014e74ee0618a162449abbbc93affected
LinuxLinux4.12affected
LinuxLinux0 < 4.12unaffected
LinuxLinux6.6.153 <= 6.6.*unaffected
LinuxLinux6.12.105 <= 6.12.*unaffected
LinuxLinux6.18.46 <= 6.18.*unaffected
LinuxLinux7.1.10 <= 7.1.*unaffected
LinuxLinux7.2 <= *unaffected

Weaknesses

References