| 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-2025-37813: usb: xhci: Fix invalid pointer dereference in Etron workaround |
| |
| Description |
| =========== |
| |
| In the Linux kernel, the following vulnerability has been resolved: |
| |
| usb: xhci: Fix invalid pointer dereference in Etron workaround |
| |
| This check is performed before prepare_transfer() and prepare_ring(), so |
| enqueue can already point at the final link TRB of a segment. And indeed |
| it will, some 0.4% of times this code is called. |
| |
| Then enqueue + 1 is an invalid pointer. It will crash the kernel right |
| away or load some junk which may look like a link TRB and cause the real |
| link TRB to be replaced with a NOOP. This wouldn't end well. |
| |
| Use a functionally equivalent test which doesn't dereference the pointer |
| and always gives correct result. |
| |
| Something has crashed my machine twice in recent days while playing with |
| an Etron HC, and a control transfer stress test ran for confirmation has |
| just crashed it again. The same test passes with this patch applied. |
| |
| The Linux kernel CVE team has assigned CVE-2025-37813 to this issue. |
| |
| |
| Affected and fixed versions |
| =========================== |
| |
| Issue introduced in 6.6.66 with commit fbc0a0c7718a6cb1dc5e0811a4f88a2b1deedfa1 and fixed in 6.6.89 with commit 142273a49f2c315eabdbdf5a71c15e479b75ca91 |
| Issue introduced in 6.12.2 with commit 9258c9ed32294ce3a4b58c9d92fc49ba030d35c9 and fixed in 6.12.26 with commit bce3055b08e303e28a8751f6073066f5c33a0744 |
| Issue introduced in 6.13 with commit 5e1c67abc9301d05130b7e267c204e7005503b33 and fixed in 6.14.5 with commit 0624e29c595b05e7a0e6d1c368f0a05799928e30 |
| Issue introduced in 6.13 with commit 5e1c67abc9301d05130b7e267c204e7005503b33 and fixed in 6.15 with commit 1ea050da5562af9b930d17cbbe9632d30f5df43a |
| Issue introduced in 6.11.11 with commit 4725344ca645a98a9d8e45e25b01a2244de5b8aa |
| |
| 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-2025-37813 |
| 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/usb/host/xhci-ring.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/142273a49f2c315eabdbdf5a71c15e479b75ca91 |
| https://git.kernel.org/stable/c/bce3055b08e303e28a8751f6073066f5c33a0744 |
| https://git.kernel.org/stable/c/0624e29c595b05e7a0e6d1c368f0a05799928e30 |
| https://git.kernel.org/stable/c/1ea050da5562af9b930d17cbbe9632d30f5df43a |
