| 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-2024-50186: net: explicitly clear the sk pointer, when pf->create fails |
| |
| Description |
| =========== |
| |
| In the Linux kernel, the following vulnerability has been resolved: |
| |
| net: explicitly clear the sk pointer, when pf->create fails |
| |
| We have recently noticed the exact same KASAN splat as in commit |
| 6cd4a78d962b ("net: do not leave a dangling sk pointer, when socket |
| creation fails"). The problem is that commit did not fully address the |
| problem, as some pf->create implementations do not use sk_common_release |
| in their error paths. |
| |
| For example, we can use the same reproducer as in the above commit, but |
| changing ping to arping. arping uses AF_PACKET socket and if packet_create |
| fails, it will just sk_free the allocated sk object. |
| |
| While we could chase all the pf->create implementations and make sure they |
| NULL the freed sk object on error from the socket, we can't guarantee |
| future protocols will not make the same mistake. |
| |
| So it is easier to just explicitly NULL the sk pointer upon return from |
| pf->create in __sock_create. We do know that pf->create always releases the |
| allocated sk object on error, so if the pointer is not NULL, it is |
| definitely dangling. |
| |
| The Linux kernel CVE team has assigned CVE-2024-50186 to this issue. |
| |
| |
| Affected and fixed versions |
| =========================== |
| |
| Issue introduced in 5.15.162 with commit 78e4aa528a7b1204219d808310524344f627d069 and fixed in 5.15.168 with commit daf462ff3cde6ecf22b98d9ae770232c10d28de2 |
| Issue introduced in 6.1.96 with commit 893eeba94c40d513cd0fe6539330ebdaea208c0e and fixed in 6.1.113 with commit b7d22a79ff4e962b8af5ffe623abd1d6c179eb9f |
| Issue introduced in 6.6.36 with commit 454c454ed645fed051216b79622f7cb69c1638f5 and fixed in 6.6.57 with commit 563e6892e21d6ecabdf62103fc4e7b326d212334 |
| Issue introduced in 6.10 with commit 6cd4a78d962bebbaf8beb7d2ead3f34120e3f7b2 and fixed in 6.11.4 with commit 8e1b72fd74bf9da3b099d09857f4e7f114f38e12 |
| Issue introduced in 6.10 with commit 6cd4a78d962bebbaf8beb7d2ead3f34120e3f7b2 and fixed in 6.12 with commit 631083143315d1b192bd7d915b967b37819e88ea |
| Issue introduced in 6.9.7 with commit 5dfe2408fd7dc4d2e7ac38a116ff0a37b1cfd3b9 |
| |
| 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-2024-50186 |
| 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/socket.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/daf462ff3cde6ecf22b98d9ae770232c10d28de2 |
| https://git.kernel.org/stable/c/b7d22a79ff4e962b8af5ffe623abd1d6c179eb9f |
| https://git.kernel.org/stable/c/563e6892e21d6ecabdf62103fc4e7b326d212334 |
| https://git.kernel.org/stable/c/8e1b72fd74bf9da3b099d09857f4e7f114f38e12 |
| https://git.kernel.org/stable/c/631083143315d1b192bd7d915b967b37819e88ea |
