| 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-2025-21758: ipv6: mcast: add RCU protection to mld_newpack() |
| |
| Description |
| =========== |
| |
| In the Linux kernel, the following vulnerability has been resolved: |
| |
| ipv6: mcast: add RCU protection to mld_newpack() |
| |
| mld_newpack() can be called without RTNL or RCU being held. |
| |
| Note that we no longer can use sock_alloc_send_skb() because |
| ipv6.igmp_sk uses GFP_KERNEL allocations which can sleep. |
| |
| Instead use alloc_skb() and charge the net->ipv6.igmp_sk |
| socket under RCU protection. |
| |
| The Linux kernel CVE team has assigned CVE-2025-21758 to this issue. |
| |
| |
| Affected and fixed versions |
| =========================== |
| |
| Issue introduced in 2.6.26 with commit b8ad0cbc58f703972e9e37c4e2a8081dd7e6a551 and fixed in 5.15.179 with commit 29fa42197f26a97cde29fa8c40beddf44ea5c8f3 |
| Issue introduced in 2.6.26 with commit b8ad0cbc58f703972e9e37c4e2a8081dd7e6a551 and fixed in 6.1.129 with commit e8af3632a7f2da83e27b083f787bced1faba00b1 |
| Issue introduced in 2.6.26 with commit b8ad0cbc58f703972e9e37c4e2a8081dd7e6a551 and fixed in 6.6.79 with commit 1b91c597b0214b1b462eb627ec02658c944623f2 |
| Issue introduced in 2.6.26 with commit b8ad0cbc58f703972e9e37c4e2a8081dd7e6a551 and fixed in 6.12.16 with commit 25195f9d5ffcc8079ad743a50c0409dbdc48d98a |
| Issue introduced in 2.6.26 with commit b8ad0cbc58f703972e9e37c4e2a8081dd7e6a551 and fixed in 6.13.4 with commit d60d493b0e65647e0335e6a7c4547abcea7df8e9 |
| Issue introduced in 2.6.26 with commit b8ad0cbc58f703972e9e37c4e2a8081dd7e6a551 and fixed in 6.14 with commit a527750d877fd334de87eef81f1cb5f0f0ca3373 |
| |
| 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-2025-21758 |
| 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/ipv6/mcast.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/29fa42197f26a97cde29fa8c40beddf44ea5c8f3 |
| https://git.kernel.org/stable/c/e8af3632a7f2da83e27b083f787bced1faba00b1 |
| https://git.kernel.org/stable/c/1b91c597b0214b1b462eb627ec02658c944623f2 |
| https://git.kernel.org/stable/c/25195f9d5ffcc8079ad743a50c0409dbdc48d98a |
| https://git.kernel.org/stable/c/d60d493b0e65647e0335e6a7c4547abcea7df8e9 |
| https://git.kernel.org/stable/c/a527750d877fd334de87eef81f1cb5f0f0ca3373 |
