CVE-2026-98027

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

State: Published
Severity: 7.0 High
Published: Sep 25, 2026
Updated: Oct 19, 2026
Reserved: Sep 25, 2026

Description

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.

Scores

CVSS	Score	Vector	Source
3.1	7.0 High	CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H	Linux

Weaknesses

The record names no weakness.

Affected Products

Product	Versions
LinuxLinux	da7dc87553046a43be1620a783ce3d9f6583d322 to before 7e4bfc5f0b66feb22cba821303fc25ca22cd0887Affected da7dc87553046a43be1620a783ce3d9f6583d322 to before 01124cd2cf4b71755b1130ac82d78dcfbd5d69e3Affected da7dc87553046a43be1620a783ce3d9f6583d322 to before 609c4378f212cf580aae02250f1146caf63d873fAffected da7dc87553046a43be1620a783ce3d9f6583d322 to before c5b5c52b6524c9fb50def2260baac745c095ec3aAffected da7dc87553046a43be1620a783ce3d9f6583d322 to before 44cd4674d9aa5bdf793b8a8b481c9e8536ed6070Affected da7dc87553046a43be1620a783ce3d9f6583d322 to before 7a683c2b062810bca203e41866389daf387c235bAffected da7dc87553046a43be1620a783ce3d9f6583d322 to before cda5ac8fe8ac8e80b1703ebb8c4250726fc19739Affected da7dc87553046a43be1620a783ce3d9f6583d322 to before b1fffc273112e7284c5b705e186b43b5770cd3d5Affected
LinuxLinux	5.4Affected before 5.4Not affected 5.10.271 through 5.10.Not affected 5.15.222 through 5.15.Not affected 6.1.189 through 6.1.Not affected 6.6.158 through 6.6.Not affected 6.12.111 through 6.12.Not affected 6.18.53 through 6.18.Not affected 7.2.7 through 7.2.*Not affected 7.3 and laterNot affected

Product

Versions

LinuxLinux

da7dc87553046a43be1620a783ce3d9f6583d322 to before 7e4bfc5f0b66feb22cba821303fc25ca22cd0887Affected
da7dc87553046a43be1620a783ce3d9f6583d322 to before 01124cd2cf4b71755b1130ac82d78dcfbd5d69e3Affected
da7dc87553046a43be1620a783ce3d9f6583d322 to before 609c4378f212cf580aae02250f1146caf63d873fAffected
da7dc87553046a43be1620a783ce3d9f6583d322 to before c5b5c52b6524c9fb50def2260baac745c095ec3aAffected
da7dc87553046a43be1620a783ce3d9f6583d322 to before 44cd4674d9aa5bdf793b8a8b481c9e8536ed6070Affected
da7dc87553046a43be1620a783ce3d9f6583d322 to before 7a683c2b062810bca203e41866389daf387c235bAffected
da7dc87553046a43be1620a783ce3d9f6583d322 to before cda5ac8fe8ac8e80b1703ebb8c4250726fc19739Affected
da7dc87553046a43be1620a783ce3d9f6583d322 to before b1fffc273112e7284c5b705e186b43b5770cd3d5Affected

LinuxLinux

5.4Affected
before 5.4Not affected
5.10.271 through 5.10.*Not affected
5.15.222 through 5.15.*Not affected
6.1.189 through 6.1.*Not affected
6.6.158 through 6.6.*Not affected
6.12.111 through 6.12.*Not affected
6.18.53 through 6.18.*Not affected
7.2.7 through 7.2.*Not affected
7.3 and laterNot affected

References

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