CVE-2026-98027

Summary

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

net: dsa: mv88e6xxx: bound the policy rule dump by the caller's buffer size

mv88e6xxx_get_rxnfc() uses rxnfc->rule_cnt as the write index while dumping the policy IDR, clobbering the input value before it has been looked at. That input is the number of entries the caller had room for. ETHTOOL_GRXCLSRLALL requires no CAP_NET_ADMIN and the ioctl sizes the buffer from the rule_cnt userspace passes in, so once an admin has installed policy rules any user can ask for fewer slots than there are rules and run off the end of the allocation. A rule_cnt of 0 leaves the buffer pointer NULL and the walk dereferences it.

Count into a local so the caller's limit survives the walk, and stop with -EMSGSIZE once it is reached.

Affected Software

VendorProductVersion RangeStatus
LinuxLinuxda7dc87553046a43be1620a783ce3d9f6583d322 < 44cd4674d9aa5bdf793b8a8b481c9e8536ed6070affected
LinuxLinuxda7dc87553046a43be1620a783ce3d9f6583d322 < 7a683c2b062810bca203e41866389daf387c235baffected
LinuxLinuxda7dc87553046a43be1620a783ce3d9f6583d322 < cda5ac8fe8ac8e80b1703ebb8c4250726fc19739affected
LinuxLinuxda7dc87553046a43be1620a783ce3d9f6583d322 < b1fffc273112e7284c5b705e186b43b5770cd3d5affected
LinuxLinux5.4affected
LinuxLinux0 < 5.4unaffected
LinuxLinux6.12.111 <= 6.12.*unaffected
LinuxLinux6.18.53 <= 6.18.*unaffected
LinuxLinux7.2.7 <= 7.2.*unaffected
LinuxLinux7.3-rc3 <= *unaffected

Weaknesses

References