Description (CNA)
In the Linux kernel, the following vulnerability has been resolved: mmmremap.c: avoid pointless invalidate_range_start/end on mremap(old_size=0) If an mremap() syscall with old_size=0 ends up in move_page_tables(), it will call invalidate_range_start()/invalidate_range_end() unnecessarily, i.e. with an empty range. This causes a WARN in KVM's mmu_notifier. In the past, empty ranges have been diagnosed to be off-by-one bugs, hence the WARNing. Given the low (so far) number of unique reports, the benefits of detecting more buggy callers seem to outweigh the cost of having to fix cases such as this one, where userspace is doing something silly. In this particular case, an early return from move_page_tables() is enough to fix the issue.
Affected (CNA)
| Vendor / product | Versions |
|---|---|
| Linux / Linux | affected 7b6efc2bc4f19952b25ebf9b236e5ac43cd386c2 before a05540f3903bd8295e8c4cd90dd3d416239a115b; affected 7b6efc2bc4f19952b25ebf9b236e5ac43cd386c2 before eeaf28e2a0128147d687237e59d5407ee1b14693; affected 7b6efc2bc4f19952b25ebf9b236e5ac43cd386c2 before e2c328c2a8f9de8b761bd4025b66c63120c55761; affected 7b6efc2bc4f19952b25ebf9b236e5ac43cd386c2 before c19d8de4e682ec4b0ea2b04a832cd8cc0be3bb31; affected 7b6efc2bc4f19952b25ebf9b236e5ac43cd386c2 before 7d659cb1763ff17d1c6ee082fa6feb4267c7a30b; affected 7b6efc2bc4f19952b25ebf9b236e5ac43cd386c2 before a04cb99c5d4668fe3f5c0e5b6da1cecd34c3f219; affected 7b6efc2bc4f19952b25ebf9b236e5ac43cd386c2 before 2358aa84ef6dafcf544a557caaa6b91afb4a0bd2; affected 7b6efc2bc4f19952b25ebf9b236e5ac43cd386c2 before 04bc13dae4a27b8d030843c85ae452bb2f1d9c1f; affected 7b6efc2bc4f19952b25ebf9b236e5ac43cd386c2 before 01e67e04c28170c47700c2c226d732bbfedb1ad0 |
| Linux / Linux | affected 3.2; unaffected 0 before 3.2; unaffected 4.9.311 through 4.9.*; unaffected 4.14.276 through 4.14.*; unaffected 4.19.238 through 4.19.*; unaffected 5.4.189 through 5.4.*; unaffected 5.10.111 through 5.10.*; unaffected 5.15.34 through 5.15.*; unaffected 5.16.20 through 5.16.*; unaffected 5.17.3 through 5.17.*; unaffected 5.18 through * |
CWE
No CWE identifiers supplied.
References
- https://git.kernel.org/stable/c/a05540f3903bd8295e8c4cd90dd3d416239a115b
- https://git.kernel.org/stable/c/eeaf28e2a0128147d687237e59d5407ee1b14693
- https://git.kernel.org/stable/c/e2c328c2a8f9de8b761bd4025b66c63120c55761
- https://git.kernel.org/stable/c/c19d8de4e682ec4b0ea2b04a832cd8cc0be3bb31
- https://git.kernel.org/stable/c/7d659cb1763ff17d1c6ee082fa6feb4267c7a30b
- https://git.kernel.org/stable/c/a04cb99c5d4668fe3f5c0e5b6da1cecd34c3f219
- https://git.kernel.org/stable/c/2358aa84ef6dafcf544a557caaa6b91afb4a0bd2
- https://git.kernel.org/stable/c/04bc13dae4a27b8d030843c85ae452bb2f1d9c1f
- https://git.kernel.org/stable/c/01e67e04c28170c47700c2c226d732bbfedb1ad0