| 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-2024-42152: nvmet: fix a possible leak when destroy a ctrl during qp establishment |
| |
| Description |
| =========== |
| |
| In the Linux kernel, the following vulnerability has been resolved: |
| |
| nvmet: fix a possible leak when destroy a ctrl during qp establishment |
| |
| In nvmet_sq_destroy we capture sq->ctrl early and if it is non-NULL we |
| know that a ctrl was allocated (in the admin connect request handler) |
| and we need to release pending AERs, clear ctrl->sqs and sq->ctrl |
| (for nvme-loop primarily), and drop the final reference on the ctrl. |
| |
| However, a small window is possible where nvmet_sq_destroy starts (as |
| a result of the client giving up and disconnecting) concurrently with |
| the nvme admin connect cmd (which may be in an early stage). But *before* |
| kill_and_confirm of sq->ref (i.e. the admin connect managed to get an sq |
| live reference). In this case, sq->ctrl was allocated however after it was |
| captured in a local variable in nvmet_sq_destroy. |
| This prevented the final reference drop on the ctrl. |
| |
| Solve this by re-capturing the sq->ctrl after all inflight request has |
| completed, where for sure sq->ctrl reference is final, and move forward |
| based on that. |
| |
| This issue was observed in an environment with many hosts connecting |
| multiple ctrls simoutanuosly, creating a delay in allocating a ctrl |
| leading up to this race window. |
| |
| The Linux kernel CVE team has assigned CVE-2024-42152 to this issue. |
| |
| |
| Affected and fixed versions |
| =========================== |
| |
| Fixed in 5.10.222 with commit 2f3c22b1d3d7e86712253244797a651998c141fa |
| Fixed in 5.15.163 with commit b4fed1443a6571d49c6ffe7d97af3bbe5ee6dff5 |
| Fixed in 6.1.98 with commit 940a71f08ef153ef807f751310b0648d1fa5d0da |
| Fixed in 6.6.39 with commit 5502c1f1d0d7472706cc1f201aecf1c935d302d1 |
| Fixed in 6.9.9 with commit 818004f2a380420c19872171be716174d4985e33 |
| Fixed in 6.10 with commit c758b77d4a0a0ed3a1292b3fd7a2aeccd1a169a4 |
| |
| 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-2024-42152 |
| 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: |
| drivers/nvme/target/core.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/2f3c22b1d3d7e86712253244797a651998c141fa |
| https://git.kernel.org/stable/c/b4fed1443a6571d49c6ffe7d97af3bbe5ee6dff5 |
| https://git.kernel.org/stable/c/940a71f08ef153ef807f751310b0648d1fa5d0da |
| https://git.kernel.org/stable/c/5502c1f1d0d7472706cc1f201aecf1c935d302d1 |
| https://git.kernel.org/stable/c/818004f2a380420c19872171be716174d4985e33 |
| https://git.kernel.org/stable/c/c758b77d4a0a0ed3a1292b3fd7a2aeccd1a169a4 |
