| 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-2024-53167: nfs/blocklayout: Don't attempt unregister for invalid block device |
| |
| Description |
| =========== |
| |
| In the Linux kernel, the following vulnerability has been resolved: |
| |
| nfs/blocklayout: Don't attempt unregister for invalid block device |
| |
| Since commit d869da91cccb ("nfs/blocklayout: Fix premature PR key |
| unregistration") an unmount of a pNFS SCSI layout-enabled NFS may |
| dereference a NULL block_device in: |
| |
| bl_unregister_scsi+0x16/0xe0 [blocklayoutdriver] |
| bl_free_device+0x70/0x80 [blocklayoutdriver] |
| bl_free_deviceid_node+0x12/0x30 [blocklayoutdriver] |
| nfs4_put_deviceid_node+0x60/0xc0 [nfsv4] |
| nfs4_deviceid_purge_client+0x132/0x190 [nfsv4] |
| unset_pnfs_layoutdriver+0x59/0x60 [nfsv4] |
| nfs4_destroy_server+0x36/0x70 [nfsv4] |
| nfs_free_server+0x23/0xe0 [nfs] |
| deactivate_locked_super+0x30/0xb0 |
| cleanup_mnt+0xba/0x150 |
| task_work_run+0x59/0x90 |
| syscall_exit_to_user_mode+0x217/0x220 |
| do_syscall_64+0x8e/0x160 |
| |
| This happens because even though we were able to create the |
| nfs4_deviceid_node, the lookup for the device was unable to attach the |
| block device to the pnfs_block_dev. |
| |
| If we never found a block device to register, we can avoid this case with |
| the PNFS_BDEV_REGISTERED flag. Move the deref behind the test for the |
| flag. |
| |
| The Linux kernel CVE team has assigned CVE-2024-53167 to this issue. |
| |
| |
| Affected and fixed versions |
| =========================== |
| |
| Issue introduced in 6.11 with commit d869da91cccb90320e101a2758f1e2b3803ade5c and fixed in 6.11.11 with commit 3402704a424f34bbcca7f4a4503859357f422217 |
| Issue introduced in 6.11 with commit d869da91cccb90320e101a2758f1e2b3803ade5c and fixed in 6.12.2 with commit faa4bacfaeed827a4ca8cb8529a3ce65a9e8ef46 |
| Issue introduced in 6.11 with commit d869da91cccb90320e101a2758f1e2b3803ade5c and fixed in 6.13 with commit 3a4ce14d9a6b868e0787e4582420b721c04ee41e |
| |
| 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-2024-53167 |
| 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/nfs/blocklayout/dev.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/3402704a424f34bbcca7f4a4503859357f422217 |
| https://git.kernel.org/stable/c/faa4bacfaeed827a4ca8cb8529a3ce65a9e8ef46 |
| https://git.kernel.org/stable/c/3a4ce14d9a6b868e0787e4582420b721c04ee41e |
