| 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-2025-21713: powerpc/pseries/iommu: Don't unset window if it was never set |
| |
| Description |
| =========== |
| |
| In the Linux kernel, the following vulnerability has been resolved: |
| |
| powerpc/pseries/iommu: Don't unset window if it was never set |
| |
| On pSeries, when user attempts to use the same vfio container used by |
| different iommu group, the spapr_tce_set_window() returns -EPERM |
| and the subsequent cleanup leads to the below crash. |
| |
| Kernel attempted to read user page (308) - exploit attempt? |
| BUG: Kernel NULL pointer dereference on read at 0x00000308 |
| Faulting instruction address: 0xc0000000001ce358 |
| Oops: Kernel access of bad area, sig: 11 [#1] |
| NIP: c0000000001ce358 LR: c0000000001ce05c CTR: c00000000005add0 |
| <snip> |
| NIP [c0000000001ce358] spapr_tce_unset_window+0x3b8/0x510 |
| LR [c0000000001ce05c] spapr_tce_unset_window+0xbc/0x510 |
| Call Trace: |
| spapr_tce_unset_window+0xbc/0x510 (unreliable) |
| tce_iommu_attach_group+0x24c/0x340 [vfio_iommu_spapr_tce] |
| vfio_container_attach_group+0xec/0x240 [vfio] |
| vfio_group_fops_unl_ioctl+0x548/0xb00 [vfio] |
| sys_ioctl+0x754/0x1580 |
| system_call_exception+0x13c/0x330 |
| system_call_vectored_common+0x15c/0x2ec |
| <snip> |
| --- interrupt: 3000 |
| |
| Fix this by having null check for the tbl passed to the |
| spapr_tce_unset_window(). |
| |
| The Linux kernel CVE team has assigned CVE-2025-21713 to this issue. |
| |
| |
| Affected and fixed versions |
| =========================== |
| |
| Issue introduced in 6.11 with commit f431a8cde7f102fce412546db6e62fdbde1131a7 and fixed in 6.12.13 with commit b853ff0b514c1df314246fcf94744005914b48cb |
| Issue introduced in 6.11 with commit f431a8cde7f102fce412546db6e62fdbde1131a7 and fixed in 6.13.2 with commit ac12372a13dab3f7a2762db240bd180de8ef1e5e |
| Issue introduced in 6.11 with commit f431a8cde7f102fce412546db6e62fdbde1131a7 and fixed in 6.14 with commit 17391cb2613b82f8c405570fea605af3255ff8d2 |
| |
| 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-2025-21713 |
| 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: |
| arch/powerpc/platforms/pseries/iommu.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/b853ff0b514c1df314246fcf94744005914b48cb |
| https://git.kernel.org/stable/c/ac12372a13dab3f7a2762db240bd180de8ef1e5e |
| https://git.kernel.org/stable/c/17391cb2613b82f8c405570fea605af3255ff8d2 |
