| 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-2024-26995: usb: typec: tcpm: Correct the PDO counting in pd_set |
| |
| Description |
| =========== |
| |
| In the Linux kernel, the following vulnerability has been resolved: |
| |
| usb: typec: tcpm: Correct the PDO counting in pd_set |
| |
| Off-by-one errors happen because nr_snk_pdo and nr_src_pdo are |
| incorrectly added one. The index of the loop is equal to the number of |
| PDOs to be updated when leaving the loop and it doesn't need to be added |
| one. |
| |
| When doing the power negotiation, TCPM relies on the "nr_snk_pdo" as |
| the size of the local sink PDO array to match the Source capabilities |
| of the partner port. If the off-by-one overflow occurs, a wrong RDO |
| might be sent and unexpected power transfer might happen such as over |
| voltage or over current (than expected). |
| |
| "nr_src_pdo" is used to set the Rp level when the port is in Source |
| role. It is also the array size of the local Source capabilities when |
| filling up the buffer which will be sent as the Source PDOs (such as |
| in Power Negotiation). If the off-by-one overflow occurs, a wrong Rp |
| level might be set and wrong Source PDOs will be sent to the partner |
| port. This could potentially cause over current or port resets. |
| |
| The Linux kernel CVE team has assigned CVE-2024-26995 to this issue. |
| |
| |
| Affected and fixed versions |
| =========================== |
| |
| Issue introduced in 6.8 with commit cd099cde4ed264403b434d8344994f97ac2a4349 and fixed in 6.8.8 with commit f3da3192cdd3fefe213390e976eec424a8e270b5 |
| Issue introduced in 6.8 with commit cd099cde4ed264403b434d8344994f97ac2a4349 and fixed in 6.9 with commit c4128304c2169b4664ed6fb6200f228cead2ab70 |
| |
| 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-2024-26995 |
| 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/typec/tcpm/tcpm.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/f3da3192cdd3fefe213390e976eec424a8e270b5 |
| https://git.kernel.org/stable/c/c4128304c2169b4664ed6fb6200f228cead2ab70 |
