| 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-2025-21832: block: don't revert iter for -EIOCBQUEUED |
| |
| Description |
| =========== |
| |
| In the Linux kernel, the following vulnerability has been resolved: |
| |
| block: don't revert iter for -EIOCBQUEUED |
| |
| blkdev_read_iter() has a few odd checks, like gating the position and |
| count adjustment on whether or not the result is bigger-than-or-equal to |
| zero (where bigger than makes more sense), and not checking the return |
| value of blkdev_direct_IO() before doing an iov_iter_revert(). The |
| latter can lead to attempting to revert with a negative value, which |
| when passed to iov_iter_revert() as an unsigned value will lead to |
| throwing a WARN_ON() because unroll is bigger than MAX_RW_COUNT. |
| |
| Be sane and don't revert for -EIOCBQUEUED, like what is done in other |
| spots. |
| |
| The Linux kernel CVE team has assigned CVE-2025-21832 to this issue. |
| |
| |
| Affected and fixed versions |
| =========================== |
| |
| Issue introduced in 5.17 with commit 3e1f941dd9f33776b3df4e30f741fe445ff773f3 and fixed in 6.1.129 with commit 6c26619effb1b4cb7d20b4e666ab8f71f6a53ccb |
| Issue introduced in 5.17 with commit 3e1f941dd9f33776b3df4e30f741fe445ff773f3 and fixed in 6.6.78 with commit 84671b0630ccb46ae9f1f99a45c7d63ffcd6a474 |
| Issue introduced in 5.17 with commit 3e1f941dd9f33776b3df4e30f741fe445ff773f3 and fixed in 6.12.14 with commit 68f16d3034a06661245ecd22f0d586a8b4e7c473 |
| Issue introduced in 5.17 with commit 3e1f941dd9f33776b3df4e30f741fe445ff773f3 and fixed in 6.13.3 with commit a58f136bad29f9ae721a29d98c042fddbee22f77 |
| Issue introduced in 5.17 with commit 3e1f941dd9f33776b3df4e30f741fe445ff773f3 and fixed in 6.14 with commit b13ee668e8280ca5b07f8ce2846b9957a8a10853 |
| |
| 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-2025-21832 |
| 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: |
| block/fops.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/6c26619effb1b4cb7d20b4e666ab8f71f6a53ccb |
| https://git.kernel.org/stable/c/84671b0630ccb46ae9f1f99a45c7d63ffcd6a474 |
| https://git.kernel.org/stable/c/68f16d3034a06661245ecd22f0d586a8b4e7c473 |
| https://git.kernel.org/stable/c/a58f136bad29f9ae721a29d98c042fddbee22f77 |
| https://git.kernel.org/stable/c/b13ee668e8280ca5b07f8ce2846b9957a8a10853 |
