| From bippy-1.1.0 Mon Sep 17 00:00:00 2001 |
| From: Greg Kroah-Hartman <gregkh@kernel.org> |
| To: <linux-cve-announce@vger.kernel.org> |
| Reply-to: <cve@kernel.org>, <linux-kernel@vger.kernel.org> |
| Subject: CVE-2023-53136: af_unix: fix struct pid leaks in OOB support |
| |
| Description |
| =========== |
| |
| In the Linux kernel, the following vulnerability has been resolved: |
| |
| af_unix: fix struct pid leaks in OOB support |
| |
| syzbot reported struct pid leak [1]. |
| |
| Issue is that queue_oob() calls maybe_add_creds() which potentially |
| holds a reference on a pid. |
| |
| But skb->destructor is not set (either directly or by calling |
| unix_scm_to_skb()) |
| |
| This means that subsequent kfree_skb() or consume_skb() would leak |
| this reference. |
| |
| In this fix, I chose to fully support scm even for the OOB message. |
| |
| [1] |
| BUG: memory leak |
| unreferenced object 0xffff8881053e7f80 (size 128): |
| comm "syz-executor242", pid 5066, jiffies 4294946079 (age 13.220s) |
| hex dump (first 32 bytes): |
| 01 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ |
| 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ |
| backtrace: |
| [<ffffffff812ae26a>] alloc_pid+0x6a/0x560 kernel/pid.c:180 |
| [<ffffffff812718df>] copy_process+0x169f/0x26c0 kernel/fork.c:2285 |
| [<ffffffff81272b37>] kernel_clone+0xf7/0x610 kernel/fork.c:2684 |
| [<ffffffff812730cc>] __do_sys_clone+0x7c/0xb0 kernel/fork.c:2825 |
| [<ffffffff849ad699>] do_syscall_x64 arch/x86/entry/common.c:50 [inline] |
| [<ffffffff849ad699>] do_syscall_64+0x39/0xb0 arch/x86/entry/common.c:80 |
| [<ffffffff84a0008b>] entry_SYSCALL_64_after_hwframe+0x63/0xcd |
| |
| The Linux kernel CVE team has assigned CVE-2023-53136 to this issue. |
| |
| |
| Affected and fixed versions |
| =========================== |
| |
| Issue introduced in 5.15 with commit 314001f0bf927015e459c9d387d62a231fe93af3 and fixed in 5.15.103 with commit f3969427fb06a2c3cd6efd7faab63505cfa76e76 |
| Issue introduced in 5.15 with commit 314001f0bf927015e459c9d387d62a231fe93af3 and fixed in 6.1.20 with commit ac1968ac399205fda9ee3b18f7de7416cb3a5d0d |
| Issue introduced in 5.15 with commit 314001f0bf927015e459c9d387d62a231fe93af3 and fixed in 6.2.7 with commit a59d6306263c38e5c0592ea4451ca26a0778c947 |
| Issue introduced in 5.15 with commit 314001f0bf927015e459c9d387d62a231fe93af3 and fixed in 6.3 with commit 2aab4b96900272885bc157f8b236abf1cdc02e08 |
| |
| 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-2023-53136 |
| 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/unix/af_unix.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/f3969427fb06a2c3cd6efd7faab63505cfa76e76 |
| https://git.kernel.org/stable/c/ac1968ac399205fda9ee3b18f7de7416cb3a5d0d |
| https://git.kernel.org/stable/c/a59d6306263c38e5c0592ea4451ca26a0778c947 |
| https://git.kernel.org/stable/c/2aab4b96900272885bc157f8b236abf1cdc02e08 |
