| From bippy-1.1.0 Mon Sep 17 00:00:00 2001 |
| From: Greg Kroah-Hartman <gregkh@kernel.org> |
| To: <linux-cve-announce@vger.kernel.org> |
| Reply-to: <cve@kernel.org>, <linux-kernel@vger.kernel.org> |
| Subject: CVE-2023-53111: loop: Fix use-after-free issues |
| |
| Description |
| =========== |
| |
| In the Linux kernel, the following vulnerability has been resolved: |
| |
| loop: Fix use-after-free issues |
| |
| do_req_filebacked() calls blk_mq_complete_request() synchronously or |
| asynchronously when using asynchronous I/O unless memory allocation fails. |
| Hence, modify loop_handle_cmd() such that it does not dereference 'cmd' nor |
| 'rq' after do_req_filebacked() finished unless we are sure that the request |
| has not yet been completed. This patch fixes the following kernel crash: |
| |
| Unable to handle kernel NULL pointer dereference at virtual address 0000000000000054 |
| Call trace: |
| css_put.42938+0x1c/0x1ac |
| loop_process_work+0xc8c/0xfd4 |
| loop_rootcg_workfn+0x24/0x34 |
| process_one_work+0x244/0x558 |
| worker_thread+0x400/0x8fc |
| kthread+0x16c/0x1e0 |
| ret_from_fork+0x10/0x20 |
| |
| The Linux kernel CVE team has assigned CVE-2023-53111 to this issue. |
| |
| |
| Affected and fixed versions |
| =========================== |
| |
| Issue introduced in 4.4 with commit bc07c10a3603a5ab3ef01ba42b3d41f9ac63d1b6 and fixed in 5.15.104 with commit 407badf73ec9fb0d5744bf2ca1745c1818aa222f |
| Issue introduced in 4.4 with commit bc07c10a3603a5ab3ef01ba42b3d41f9ac63d1b6 and fixed in 6.1.21 with commit e3fda704903f6d1fc351412f1bc6620333959ada |
| Issue introduced in 4.4 with commit bc07c10a3603a5ab3ef01ba42b3d41f9ac63d1b6 and fixed in 6.2.8 with commit 6917395c4667cfb607ed8bf1826205a59414657c |
| Issue introduced in 4.4 with commit bc07c10a3603a5ab3ef01ba42b3d41f9ac63d1b6 and fixed in 6.3 with commit 9b0cb770f5d7b1ff40bea7ca385438ee94570eec |
| |
| 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-2023-53111 |
| 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/block/loop.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/407badf73ec9fb0d5744bf2ca1745c1818aa222f |
| https://git.kernel.org/stable/c/e3fda704903f6d1fc351412f1bc6620333959ada |
| https://git.kernel.org/stable/c/6917395c4667cfb607ed8bf1826205a59414657c |
| https://git.kernel.org/stable/c/9b0cb770f5d7b1ff40bea7ca385438ee94570eec |
