| 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-2025-21671: zram: fix potential UAF of zram table |
| |
| Description |
| =========== |
| |
| In the Linux kernel, the following vulnerability has been resolved: |
| |
| zram: fix potential UAF of zram table |
| |
| If zram_meta_alloc failed early, it frees allocated zram->table without |
| setting it NULL. Which will potentially cause zram_meta_free to access |
| the table if user reset an failed and uninitialized device. |
| |
| The Linux kernel CVE team has assigned CVE-2025-21671 to this issue. |
| |
| |
| Affected and fixed versions |
| =========================== |
| |
| Issue introduced in 6.1.122 with commit ac3b5366b9b7c9d97b606532ceab43d2329a22f3 and fixed in 6.1.127 with commit fe3de867f94819ba0f28e035c0b0182150147d95 |
| Issue introduced in 6.6.68 with commit 0b5b0b65561b34e6e360de317e4bcd031bfabf42 and fixed in 6.6.74 with commit 571d3f6045cd3a6d9f6aec33b678f3ffe97582ef |
| Issue introduced in 6.12.7 with commit 6fb92e9a52e3feae309a213950f21dfcd1eb0b40 and fixed in 6.12.11 with commit 902ef8f16d5ca77edc77c30656be54186c1e99b7 |
| |
| 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-2025-21671 |
| 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/block/zram/zram_drv.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/fe3de867f94819ba0f28e035c0b0182150147d95 |
| https://git.kernel.org/stable/c/571d3f6045cd3a6d9f6aec33b678f3ffe97582ef |
| https://git.kernel.org/stable/c/902ef8f16d5ca77edc77c30656be54186c1e99b7 |
| https://git.kernel.org/stable/c/212fe1c0df4a150fb6298db2cfff267ceaba5402 |
