| 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-2024-44963: btrfs: do not BUG_ON() when freeing tree block after error |
| |
| Description |
| =========== |
| |
| In the Linux kernel, the following vulnerability has been resolved: |
| |
| btrfs: do not BUG_ON() when freeing tree block after error |
| |
| When freeing a tree block, at btrfs_free_tree_block(), if we fail to |
| create a delayed reference we don't deal with the error and just do a |
| BUG_ON(). The error most likely to happen is -ENOMEM, and we have a |
| comment mentioning that only -ENOMEM can happen, but that is not true, |
| because in case qgroups are enabled any error returned from |
| btrfs_qgroup_trace_extent_post() (can be -EUCLEAN or anything returned |
| from btrfs_search_slot() for example) can be propagated back to |
| btrfs_free_tree_block(). |
| |
| So stop doing a BUG_ON() and return the error to the callers and make |
| them abort the transaction to prevent leaking space. Syzbot was |
| triggering this, likely due to memory allocation failure injection. |
| |
| The Linux kernel CVE team has assigned CVE-2024-44963 to this issue. |
| |
| |
| Affected and fixed versions |
| =========================== |
| |
| Fixed in 6.6.64 with commit 22d907bcd283d69d5e60497fc0d51969545c583b |
| Fixed in 6.10.5 with commit 98251cd60b4d702a8a81de442ab621e83a3fb24f |
| Fixed in 6.11 with commit bb3868033a4cccff7be57e9145f2117cbdc91c11 |
| |
| 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-2024-44963 |
| 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/ctree.c |
| fs/btrfs/extent-tree.c |
| fs/btrfs/extent-tree.h |
| fs/btrfs/free-space-tree.c |
| fs/btrfs/ioctl.c |
| fs/btrfs/qgroup.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/22d907bcd283d69d5e60497fc0d51969545c583b |
| https://git.kernel.org/stable/c/98251cd60b4d702a8a81de442ab621e83a3fb24f |
| https://git.kernel.org/stable/c/bb3868033a4cccff7be57e9145f2117cbdc91c11 |
