| From bippy-1.2.0 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-2025-23138: watch_queue: fix pipe accounting mismatch |
| |
| Description |
| =========== |
| |
| In the Linux kernel, the following vulnerability has been resolved: |
| |
| watch_queue: fix pipe accounting mismatch |
| |
| Currently, watch_queue_set_size() modifies the pipe buffers charged to |
| user->pipe_bufs without updating the pipe->nr_accounted on the pipe |
| itself, due to the if (!pipe_has_watch_queue()) test in |
| pipe_resize_ring(). This means that when the pipe is ultimately freed, |
| we decrement user->pipe_bufs by something other than what than we had |
| charged to it, potentially leading to an underflow. This in turn can |
| cause subsequent too_many_pipe_buffers_soft() tests to fail with -EPERM. |
| |
| To remedy this, explicitly account for the pipe usage in |
| watch_queue_set_size() to match the number set via account_pipe_buffers() |
| |
| (It's unclear why watch_queue_set_size() does not update nr_accounted; |
| it may be due to intentional overprovisioning in watch_queue_set_size()?) |
| |
| The Linux kernel CVE team has assigned CVE-2025-23138 to this issue. |
| |
| |
| Affected and fixed versions |
| =========================== |
| |
| Issue introduced in 5.10.210 with commit 162ae0e78bdabf84ef10c1293c4ed7865cb7d3c8 and fixed in 5.10.236 with commit 8658c75343ed00e5e154ebbe24335f51ba8db547 |
| Issue introduced in 5.15.149 with commit 3efbd114b91525bb095b8ae046382197d92126b9 and fixed in 5.15.180 with commit 471c89b7d4f58bd6082f7c1fe14d4ca15c7f1284 |
| Issue introduced in 6.1.76 with commit b87a1229d8668fbc78ebd9ca0fc797a76001c60f and fixed in 6.1.134 with commit d40e3537265dea9e3c33021874437ff26dc18787 |
| Issue introduced in 6.6.15 with commit 68e51bdb1194f11d3452525b99c98aff6f837b24 and fixed in 6.6.87 with commit 6dafa27764183738dc5368b669b71e3d0d154f12 |
| Issue introduced in 6.8 with commit e95aada4cb93d42e25c30a0ef9eb2923d9711d4a and fixed in 6.12.23 with commit 56ec918e6c86c1536870e4373e91eddd0c44245f |
| Issue introduced in 6.8 with commit e95aada4cb93d42e25c30a0ef9eb2923d9711d4a and fixed in 6.13.11 with commit 2d680b988656bb556c863d8b46d9b9096842bf3d |
| Issue introduced in 6.8 with commit e95aada4cb93d42e25c30a0ef9eb2923d9711d4a and fixed in 6.14.2 with commit 205028ebba838938d3b264dda1d0708fa7fe1ade |
| Issue introduced in 6.8 with commit e95aada4cb93d42e25c30a0ef9eb2923d9711d4a and fixed in 6.15 with commit f13abc1e8e1a3b7455511c4e122750127f6bc9b0 |
| Issue introduced in 6.7.3 with commit 6fb70694f8d1ac34e45246b0ac988f025e1e5b55 |
| |
| 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-2025-23138 |
| 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: |
| kernel/watch_queue.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/8658c75343ed00e5e154ebbe24335f51ba8db547 |
| https://git.kernel.org/stable/c/471c89b7d4f58bd6082f7c1fe14d4ca15c7f1284 |
| https://git.kernel.org/stable/c/d40e3537265dea9e3c33021874437ff26dc18787 |
| https://git.kernel.org/stable/c/6dafa27764183738dc5368b669b71e3d0d154f12 |
| https://git.kernel.org/stable/c/56ec918e6c86c1536870e4373e91eddd0c44245f |
| https://git.kernel.org/stable/c/2d680b988656bb556c863d8b46d9b9096842bf3d |
| https://git.kernel.org/stable/c/205028ebba838938d3b264dda1d0708fa7fe1ade |
| https://git.kernel.org/stable/c/f13abc1e8e1a3b7455511c4e122750127f6bc9b0 |
