| 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-2024-46762: xen: privcmd: Fix possible access to a freed kirqfd instance |
| |
| Description |
| =========== |
| |
| In the Linux kernel, the following vulnerability has been resolved: |
| |
| xen: privcmd: Fix possible access to a freed kirqfd instance |
| |
| Nothing prevents simultaneous ioctl calls to privcmd_irqfd_assign() and |
| privcmd_irqfd_deassign(). If that happens, it is possible that a kirqfd |
| created and added to the irqfds_list by privcmd_irqfd_assign() may get |
| removed by another thread executing privcmd_irqfd_deassign(), while the |
| former is still using it after dropping the locks. |
| |
| This can lead to a situation where an already freed kirqfd instance may |
| be accessed and cause kernel oops. |
| |
| Use SRCU locking to prevent the same, as is done for the KVM |
| implementation for irqfds. |
| |
| The Linux kernel CVE team has assigned CVE-2024-46762 to this issue. |
| |
| |
| Affected and fixed versions |
| =========================== |
| |
| Fixed in 6.6.51 with commit e997b357b13a7d95de31681fc54fcc34235fa527 |
| Fixed in 6.10.10 with commit 112fd2f02b308564724b8e81006c254d20945c4b |
| Fixed in 6.11 with commit 611ff1b1ae989a7bcce3e2a8e132ee30e968c557 |
| |
| 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-2024-46762 |
| 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/xen/privcmd.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/e997b357b13a7d95de31681fc54fcc34235fa527 |
| https://git.kernel.org/stable/c/112fd2f02b308564724b8e81006c254d20945c4b |
| https://git.kernel.org/stable/c/611ff1b1ae989a7bcce3e2a8e132ee30e968c557 |
