Description
In the Linux kernel, the following vulnerability has been resolved: net/sched: fix pedit partial COW leading to page cache corruption tcf_pedit_act() computes the COW range for skb_ensure_writable() once before the key loop using tcfp_off_max_hint, but the hint does not account for the runtime header offset added by typed keys. This can leave part of the write region un-COW'd. Fix by moving skb_ensure_writable() inside the per-key loop where the actual write offset is known, and add overflow checking on the offset arithmetic. For negative offsets (e.g. Ethernet header edits at ingress), use skb_cow() to COW the headroom instead. Guard offset_valid() against INT_MIN, where negation is undefined.
CVSS breakdown
CVSS 3.1
Attack Vector
Local
Attack Complexity
Low
Privileges Required
Low
User Interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
High
Availability
High
Affected products
- Linux / Linux8b796475fd7882663a870456466a4fb315cc1bd6 – 2bec122b9fb91507a758ab5e3e5c4fbe7cb3f61b
- Linux / Linux8b796475fd7882663a870456466a4fb315cc1bd6 – b198ed4e52580a7238c7c7082f03906f8b310313
- Linux / Linux8b796475fd7882663a870456466a4fb315cc1bd6 – 3dee9d0c198faeb95d052c1b94c2958751a28512
- Linux / Linux8b796475fd7882663a870456466a4fb315cc1bd6 – 899ee91156e57784090c5565e4f31bd7dbffbc5a
- Linux / Linuxd0c38a914b0c4c21d553da801003d36979016726 – d0c38a914b0c4c21d553da801003d36979016726
- Linux / Linux2ec2dd7d51a9320151f275ddbb2b53260fb32ca1 – 2ec2dd7d51a9320151f275ddbb2b53260fb32ca1
- Linux / Linuxabe35bf3be51482593076d516a680d79e5fbc8e1 – abe35bf3be51482593076d516a680d79e5fbc8e1
- Linux / Linuxb773640d5bb9e2acfd91e2695717af04d47aa116 – b773640d5bb9e2acfd91e2695717af04d47aa116
- Linux / Linuxc19cc520b3d69904e9518d401ad0df7f4702aca0 – c19cc520b3d69904e9518d401ad0df7f4702aca0
- Linux / Linux4.19.244 – 4.20
- Linux / Linux5.4.195 – 5.5
- Linux / Linux5.10.117 – 5.11
- Linux / Linux5.15.41 – 5.16
- Linux / Linux5.17.9 – 5.18
- Linux / Linux5.18 – 5.18
- Linux / Linux0 – 5.18
- Linux / Linux6.12.94 – 6.12.*
- Linux / Linux6.18.36 – 6.18.*
- Linux / Linux7.0.13 – 7.0.*
- Linux / Linux7.1 – *
News coverage
- New Linux pedit COW Exploit Enables Root Access by Poisoning Cached BinariesThe Hacker News · 3d ago
References
- MISChttps://git.kernel.org/stable/c/2bec122b9fb91507a758ab5e3e5c4fbe7cb3f61b
- MISChttps://git.kernel.org/stable/c/b198ed4e52580a7238c7c7082f03906f8b310313
- MISChttps://git.kernel.org/stable/c/3dee9d0c198faeb95d052c1b94c2958751a28512
- MISChttps://git.kernel.org/stable/c/899ee91156e57784090c5565e4f31bd7dbffbc5a