| 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-2024-56624: iommufd: Fix out_fput in iommufd_fault_alloc() |
| |
| Description |
| =========== |
| |
| In the Linux kernel, the following vulnerability has been resolved: |
| |
| iommufd: Fix out_fput in iommufd_fault_alloc() |
| |
| As fput() calls the file->f_op->release op, where fault obj and ictx are |
| getting released, there is no need to release these two after fput() one |
| more time, which would result in imbalanced refcounts: |
| refcount_t: decrement hit 0; leaking memory. |
| WARNING: CPU: 48 PID: 2369 at lib/refcount.c:31 refcount_warn_saturate+0x60/0x230 |
| Call trace: |
| refcount_warn_saturate+0x60/0x230 (P) |
| refcount_warn_saturate+0x60/0x230 (L) |
| iommufd_fault_fops_release+0x9c/0xe0 [iommufd] |
| ... |
| VFS: Close: file count is 0 (f_op=iommufd_fops [iommufd]) |
| WARNING: CPU: 48 PID: 2369 at fs/open.c:1507 filp_flush+0x3c/0xf0 |
| Call trace: |
| filp_flush+0x3c/0xf0 (P) |
| filp_flush+0x3c/0xf0 (L) |
| __arm64_sys_close+0x34/0x98 |
| ... |
| imbalanced put on file reference count |
| WARNING: CPU: 48 PID: 2369 at fs/file.c:74 __file_ref_put+0x100/0x138 |
| Call trace: |
| __file_ref_put+0x100/0x138 (P) |
| __file_ref_put+0x100/0x138 (L) |
| __fput_sync+0x4c/0xd0 |
| |
| Drop those two lines to fix the warnings above. |
| |
| The Linux kernel CVE team has assigned CVE-2024-56624 to this issue. |
| |
| |
| Affected and fixed versions |
| =========================== |
| |
| Issue introduced in 6.11 with commit 07838f7fd529c8a6de44b601d4b7057e6c8d36ed and fixed in 6.12.5 with commit 2b3f30c8edbf9a122ce01f13f0f41fbca5f1d41d |
| Issue introduced in 6.11 with commit 07838f7fd529c8a6de44b601d4b7057e6c8d36ed and fixed in 6.13 with commit af7f4780514f850322b2959032ecaa96e4b26472 |
| |
| 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-2024-56624 |
| 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/iommu/iommufd/fault.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/2b3f30c8edbf9a122ce01f13f0f41fbca5f1d41d |
| https://git.kernel.org/stable/c/af7f4780514f850322b2959032ecaa96e4b26472 |
