| 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-2024-50010: exec: don't WARN for racy path_noexec check |
| |
| Description |
| =========== |
| |
| In the Linux kernel, the following vulnerability has been resolved: |
| |
| exec: don't WARN for racy path_noexec check |
| |
| Both i_mode and noexec checks wrapped in WARN_ON stem from an artifact |
| of the previous implementation. They used to legitimately check for the |
| condition, but that got moved up in two commits: |
| 633fb6ac3980 ("exec: move S_ISREG() check earlier") |
| 0fd338b2d2cd ("exec: move path_noexec() check earlier") |
| |
| Instead of being removed said checks are WARN_ON'ed instead, which |
| has some debug value. |
| |
| However, the spurious path_noexec check is racy, resulting in |
| unwarranted warnings should someone race with setting the noexec flag. |
| |
| One can note there is more to perm-checking whether execve is allowed |
| and none of the conditions are guaranteed to still hold after they were |
| tested for. |
| |
| Additionally this does not validate whether the code path did any perm |
| checking to begin with -- it will pass if the inode happens to be |
| regular. |
| |
| Keep the redundant path_noexec() check even though it's mindless |
| nonsense checking for guarantee that isn't given so drop the WARN. |
| |
| Reword the commentary and do small tidy ups while here. |
| |
| [brauner: keep redundant path_noexec() check] |
| |
| The Linux kernel CVE team has assigned CVE-2024-50010 to this issue. |
| |
| |
| Affected and fixed versions |
| =========================== |
| |
| Fixed in 5.10.229 with commit c9b77438077d5a20c79ead95bcdaf9bd4797baaf |
| Fixed in 5.15.170 with commit b723f96407a0a078cf75970e4dbf16b46d286a61 |
| Fixed in 6.1.115 with commit 0bdf77be2330062b3a64f2bec39f62ab874a6796 |
| Fixed in 6.6.59 with commit 0d16f53c91111cec914f0811fcc526a2ba77b20d |
| Fixed in 6.12 with commit 0d196e7589cefe207d5d41f37a0a28a1fdeeb7c6 |
| |
| 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-2024-50010 |
| 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: |
| fs/exec.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/c9b77438077d5a20c79ead95bcdaf9bd4797baaf |
| https://git.kernel.org/stable/c/b723f96407a0a078cf75970e4dbf16b46d286a61 |
| https://git.kernel.org/stable/c/0bdf77be2330062b3a64f2bec39f62ab874a6796 |
| https://git.kernel.org/stable/c/0d16f53c91111cec914f0811fcc526a2ba77b20d |
| https://git.kernel.org/stable/c/0d196e7589cefe207d5d41f37a0a28a1fdeeb7c6 |
