| 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-2024-26752: l2tp: pass correct message length to ip6_append_data |
| |
| Description |
| =========== |
| |
| In the Linux kernel, the following vulnerability has been resolved: |
| |
| l2tp: pass correct message length to ip6_append_data |
| |
| l2tp_ip6_sendmsg needs to avoid accounting for the transport header |
| twice when splicing more data into an already partially-occupied skbuff. |
| |
| To manage this, we check whether the skbuff contains data using |
| skb_queue_empty when deciding how much data to append using |
| ip6_append_data. |
| |
| However, the code which performed the calculation was incorrect: |
| |
| ulen = len + skb_queue_empty(&sk->sk_write_queue) ? transhdrlen : 0; |
| |
| ...due to C operator precedence, this ends up setting ulen to |
| transhdrlen for messages with a non-zero length, which results in |
| corrupted packets on the wire. |
| |
| Add parentheses to correct the calculation in line with the original |
| intent. |
| |
| The Linux kernel CVE team has assigned CVE-2024-26752 to this issue. |
| |
| |
| Affected and fixed versions |
| =========================== |
| |
| Issue introduced in 4.19.296 with commit 559d697c5d072593d22b3e0bd8b8081108aeaf59 and fixed in 4.19.308 with commit 4c3ce64bc9d36ca9164dd6c77ff144c121011aae |
| Issue introduced in 5.4.258 with commit 1fc793d68d50dee4782ef2e808913d5dd880bcc6 and fixed in 5.4.270 with commit c1d3a84a67db910ce28a871273c992c3d7f9efb5 |
| Issue introduced in 5.10.198 with commit 96b2e1090397217839fcd6c9b6d8f5d439e705ed and fixed in 5.10.211 with commit dcb4d14268595065c85dc5528056713928e17243 |
| Issue introduced in 5.15.135 with commit cd1189956393bf850b2e275e37411855d3bd86bb and fixed in 5.15.150 with commit 0da15a70395182ee8cb75716baf00dddc0bea38d |
| Issue introduced in 6.1.57 with commit f6a7182179c0ed788e3755ee2ed18c888ddcc33f and fixed in 6.1.80 with commit 13cd1daeea848614e585b2c6ecc11ca9c8ab2500 |
| Issue introduced in 6.6 with commit 9d4c75800f61e5d75c1659ba201b6c0c7ead3070 and fixed in 6.6.19 with commit 804bd8650a3a2bf3432375f8c97d5049d845ce56 |
| Issue introduced in 6.6 with commit 9d4c75800f61e5d75c1659ba201b6c0c7ead3070 and fixed in 6.7.7 with commit 83340c66b498e49353530e41542500fc8a4782d6 |
| Issue introduced in 6.6 with commit 9d4c75800f61e5d75c1659ba201b6c0c7ead3070 and fixed in 6.8 with commit 359e54a93ab43d32ee1bff3c2f9f10cb9f6b6e79 |
| Issue introduced in 4.14.327 with commit 7626b9fed53092aa2147978070e610ecb61af844 |
| Issue introduced in 6.5.7 with commit fe80658c08e3001c80c5533cd41abfbb0e0e28fd |
| |
| 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-2024-26752 |
| 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/l2tp/l2tp_ip6.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/4c3ce64bc9d36ca9164dd6c77ff144c121011aae |
| https://git.kernel.org/stable/c/c1d3a84a67db910ce28a871273c992c3d7f9efb5 |
| https://git.kernel.org/stable/c/dcb4d14268595065c85dc5528056713928e17243 |
| https://git.kernel.org/stable/c/0da15a70395182ee8cb75716baf00dddc0bea38d |
| https://git.kernel.org/stable/c/13cd1daeea848614e585b2c6ecc11ca9c8ab2500 |
| https://git.kernel.org/stable/c/804bd8650a3a2bf3432375f8c97d5049d845ce56 |
| https://git.kernel.org/stable/c/83340c66b498e49353530e41542500fc8a4782d6 |
| https://git.kernel.org/stable/c/359e54a93ab43d32ee1bff3c2f9f10cb9f6b6e79 |
