| From bippy-5f407fcff5a0 Mon Sep 17 00:00:00 2001 |
| From: Greg Kroah-Hartman <gregkh@linuxfoundation.org> |
| To: <linux-cve-announce@vger.kernel.org> |
| Reply-to: <cve@kernel.org>, <linux-kernel@vger.kernel.org> |
| Subject: CVE-2024-36000: mm/hugetlb: fix missing hugetlb_lock for resv uncharge |
| |
| Description |
| =========== |
| |
| In the Linux kernel, the following vulnerability has been resolved: |
| |
| mm/hugetlb: fix missing hugetlb_lock for resv uncharge |
| |
| There is a recent report on UFFDIO_COPY over hugetlb: |
| |
| https://lore.kernel.org/all/000000000000ee06de0616177560@google.com/ |
| |
| 350: lockdep_assert_held(&hugetlb_lock); |
| |
| Should be an issue in hugetlb but triggered in an userfault context, where |
| it goes into the unlikely path where two threads modifying the resv map |
| together. Mike has a fix in that path for resv uncharge but it looks like |
| the locking criteria was overlooked: hugetlb_cgroup_uncharge_folio_rsvd() |
| will update the cgroup pointer, so it requires to be called with the lock |
| held. |
| |
| The Linux kernel CVE team has assigned CVE-2024-36000 to this issue. |
| |
| |
| Affected and fixed versions |
| =========================== |
| |
| Issue introduced in 5.10 with commit 79aa925bf239c234be8586780e482872dc4690dd and fixed in 6.1.91 with commit 4c806333efea1000a2a9620926f560ad2e1ca7cc |
| Issue introduced in 5.10 with commit 79aa925bf239c234be8586780e482872dc4690dd and fixed in 6.6.30 with commit f6c5d21db16a0910152ec8aa9d5a7aed72694505 |
| Issue introduced in 5.10 with commit 79aa925bf239c234be8586780e482872dc4690dd and fixed in 6.8.9 with commit 538faabf31e9c53d8c870d114846fda958a0de10 |
| Issue introduced in 5.10 with commit 79aa925bf239c234be8586780e482872dc4690dd and fixed in 6.9 with commit b76b46902c2d0395488c8412e1116c2486cdfcb2 |
| Issue introduced in 5.9.7 with commit f87004c0b2bdf0f1066b88795d8e6c1dfad6cea0 |
| |
| Please see https://www.kernel.org for a full list of currently supported |
| kernel versions by the kernel community. |
| |
| Unaffected versions might change over time as fixes are backported to |
| older supported kernel versions. The official CVE entry at |
| https://cve.org/CVERecord/?id=CVE-2024-36000 |
| will be updated if fixes are backported, please check that for the most |
| up to date information about this issue. |
| |
| |
| Affected files |
| ============== |
| |
| The file(s) affected by this issue are: |
| mm/hugetlb.c |
| |
| |
| Mitigation |
| ========== |
| |
| The Linux kernel CVE team recommends that you update to the latest |
| stable kernel version for this, and many other bugfixes. Individual |
| changes are never tested alone, but rather are part of a larger kernel |
| release. Cherry-picking individual commits is not recommended or |
| supported by the Linux kernel community at all. If however, updating to |
| the latest release is impossible, the individual changes to resolve this |
| issue can be found at these commits: |
| https://git.kernel.org/stable/c/4c806333efea1000a2a9620926f560ad2e1ca7cc |
| https://git.kernel.org/stable/c/f6c5d21db16a0910152ec8aa9d5a7aed72694505 |
| https://git.kernel.org/stable/c/538faabf31e9c53d8c870d114846fda958a0de10 |
| https://git.kernel.org/stable/c/b76b46902c2d0395488c8412e1116c2486cdfcb2 |
