Description (CNA)
In the Linux kernel, the following vulnerability has been resolved: ipv4: stop route notification sizing when nexthop group shrinks Commit 680aea08e78c ("net: ipv4: Emit notification when fib hardware flags are changed") added an RCU-only fib_nlmsg_size() call for asynchronous hardware flag notifications. fib_nlmsg_size() checks fib_info_num_path() before each iteration, then fib_info_nhc() independently reloads nh->nh_grp. If RTM_NEWNEXTHOP replaces a group with fewer paths between those loads, fib_info_nhc() returns NULL and fib_nexthop_nlmsg_size() dereferences it. Stop sizing when the indexed path is absent. Nexthop groups are dense, so the current snapshot has no later path.
Affected (CNA)
| Vendor / product | Versions |
|---|---|
| Linux / Linux | affected 680aea08e78c003292415518ad270bc20f9c80b1 before 72d9d17092bb37b0717f12042a0817d01a1f9e78; affected 680aea08e78c003292415518ad270bc20f9c80b1 before ad1c9f1b98c92609e9bb2ae8f05916defc3b0a54; affected 680aea08e78c003292415518ad270bc20f9c80b1 before c1f48d1c2d5e9efd904dbbc2f2b3d41543e55c49; affected 680aea08e78c003292415518ad270bc20f9c80b1 before ad2b3a68b8a7d5d27de88e05674e4adb1ce46d88; affected 680aea08e78c003292415518ad270bc20f9c80b1 before d3daa33c7af92e38f2274bbd2576f58bfbaf89e6 |
| Linux / Linux | affected 5.12; unaffected 0 before 5.12; unaffected 6.6.160 through 6.6.*; unaffected 6.12.113 through 6.12.*; unaffected 6.18.57 through 6.18.*; unaffected 7.2.11 through 7.2.*; unaffected 7.3 through * |
CWE
No CWE identifiers supplied.
References
- https://git.kernel.org/stable/c/72d9d17092bb37b0717f12042a0817d01a1f9e78
- https://git.kernel.org/stable/c/ad1c9f1b98c92609e9bb2ae8f05916defc3b0a54
- https://git.kernel.org/stable/c/c1f48d1c2d5e9efd904dbbc2f2b3d41543e55c49
- https://git.kernel.org/stable/c/ad2b3a68b8a7d5d27de88e05674e4adb1ce46d88
- https://git.kernel.org/stable/c/d3daa33c7af92e38f2274bbd2576f58bfbaf89e6