| 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-2024-50273: btrfs: reinitialize delayed ref list after deleting it from the list |
| |
| Description |
| =========== |
| |
| In the Linux kernel, the following vulnerability has been resolved: |
| |
| btrfs: reinitialize delayed ref list after deleting it from the list |
| |
| At insert_delayed_ref() if we need to update the action of an existing |
| ref to BTRFS_DROP_DELAYED_REF, we delete the ref from its ref head's |
| ref_add_list using list_del(), which leaves the ref's add_list member |
| not reinitialized, as list_del() sets the next and prev members of the |
| list to LIST_POISON1 and LIST_POISON2, respectively. |
| |
| If later we end up calling drop_delayed_ref() against the ref, which can |
| happen during merging or when destroying delayed refs due to a transaction |
| abort, we can trigger a crash since at drop_delayed_ref() we call |
| list_empty() against the ref's add_list, which returns false since |
| the list was not reinitialized after the list_del() and as a consequence |
| we call list_del() again at drop_delayed_ref(). This results in an |
| invalid list access since the next and prev members are set to poison |
| pointers, resulting in a splat if CONFIG_LIST_HARDENED and |
| CONFIG_DEBUG_LIST are set or invalid poison pointer dereferences |
| otherwise. |
| |
| So fix this by deleting from the list with list_del_init() instead. |
| |
| The Linux kernel CVE team has assigned CVE-2024-50273 to this issue. |
| |
| |
| Affected and fixed versions |
| =========================== |
| |
| Issue introduced in 4.10 with commit 1d57ee941692d0cc928526e21a1557b2ae3e11db and fixed in 4.19.324 with commit 2fd0948a483e9cb2d669c7199bc620a21c97673d |
| Issue introduced in 4.10 with commit 1d57ee941692d0cc928526e21a1557b2ae3e11db and fixed in 5.4.286 with commit 93c5b8decc0ef39ba84f4211d2db6da0a4aefbeb |
| Issue introduced in 4.10 with commit 1d57ee941692d0cc928526e21a1557b2ae3e11db and fixed in 5.10.230 with commit bf0b0c6d159767c0d1c21f793950d78486690ee0 |
| Issue introduced in 4.10 with commit 1d57ee941692d0cc928526e21a1557b2ae3e11db and fixed in 5.15.172 with commit c24fa427fc0ae827b2a3a07f13738cbf82c3f851 |
| Issue introduced in 4.10 with commit 1d57ee941692d0cc928526e21a1557b2ae3e11db and fixed in 6.1.117 with commit 2cb1a73d1d44a1c11b0ee5eeced765dd80ec48e6 |
| Issue introduced in 4.10 with commit 1d57ee941692d0cc928526e21a1557b2ae3e11db and fixed in 6.6.61 with commit f04be6d68f715c1473a8422fc0460f57b5e99931 |
| Issue introduced in 4.10 with commit 1d57ee941692d0cc928526e21a1557b2ae3e11db and fixed in 6.11.8 with commit 50a3933760b427759afdd23156a7280a19357a92 |
| Issue introduced in 4.10 with commit 1d57ee941692d0cc928526e21a1557b2ae3e11db and fixed in 6.12 with commit c9a75ec45f1111ef530ab186c2a7684d0a0c9245 |
| |
| 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-2024-50273 |
| 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: |
| fs/btrfs/delayed-ref.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/2fd0948a483e9cb2d669c7199bc620a21c97673d |
| https://git.kernel.org/stable/c/93c5b8decc0ef39ba84f4211d2db6da0a4aefbeb |
| https://git.kernel.org/stable/c/bf0b0c6d159767c0d1c21f793950d78486690ee0 |
| https://git.kernel.org/stable/c/c24fa427fc0ae827b2a3a07f13738cbf82c3f851 |
| https://git.kernel.org/stable/c/2cb1a73d1d44a1c11b0ee5eeced765dd80ec48e6 |
| https://git.kernel.org/stable/c/f04be6d68f715c1473a8422fc0460f57b5e99931 |
| https://git.kernel.org/stable/c/50a3933760b427759afdd23156a7280a19357a92 |
| https://git.kernel.org/stable/c/c9a75ec45f1111ef530ab186c2a7684d0a0c9245 |
