| 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-2021-46973: net: qrtr: Avoid potential use after free in MHI send |
| |
| Description |
| =========== |
| |
| In the Linux kernel, the following vulnerability has been resolved: |
| |
| net: qrtr: Avoid potential use after free in MHI send |
| |
| It is possible that the MHI ul_callback will be invoked immediately |
| following the queueing of the skb for transmission, leading to the |
| callback decrementing the refcount of the associated sk and freeing the |
| skb. |
| |
| As such the dereference of skb and the increment of the sk refcount must |
| happen before the skb is queued, to avoid the skb to be used after free |
| and potentially the sk to drop its last refcount.. |
| |
| The Linux kernel CVE team has assigned CVE-2021-46973 to this issue. |
| |
| |
| Affected and fixed versions |
| =========================== |
| |
| Issue introduced in 5.8 with commit 6e728f321393b1fce9e1c2c3e55f9f7c15991321 and fixed in 5.10.35 with commit 48ec949ac979b4b42d740f67b6177797af834f80 |
| Issue introduced in 5.8 with commit 6e728f321393b1fce9e1c2c3e55f9f7c15991321 and fixed in 5.11.19 with commit ea474054c2cc6e1284604b21361f475c7cc8c0a0 |
| Issue introduced in 5.8 with commit 6e728f321393b1fce9e1c2c3e55f9f7c15991321 and fixed in 5.12.2 with commit 03c649dee8b1eb5600212a249542a70f47a5ab40 |
| Issue introduced in 5.8 with commit 6e728f321393b1fce9e1c2c3e55f9f7c15991321 and fixed in 5.13 with commit 47a017f33943278570c072bc71681809b2567b3a |
| |
| 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-2021-46973 |
| 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: |
| net/qrtr/mhi.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/48ec949ac979b4b42d740f67b6177797af834f80 |
| https://git.kernel.org/stable/c/ea474054c2cc6e1284604b21361f475c7cc8c0a0 |
| https://git.kernel.org/stable/c/03c649dee8b1eb5600212a249542a70f47a5ab40 |
| https://git.kernel.org/stable/c/47a017f33943278570c072bc71681809b2567b3a |
