| From bippy-7c5fe7eed585 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-2022-49636: vlan: fix memory leak in vlan_newlink() |
| |
| Description |
| =========== |
| |
| In the Linux kernel, the following vulnerability has been resolved: |
| |
| vlan: fix memory leak in vlan_newlink() |
| |
| Blamed commit added back a bug I fixed in commit 9bbd917e0bec |
| ("vlan: fix memory leak in vlan_dev_set_egress_priority") |
| |
| If a memory allocation fails in vlan_changelink() after other allocations |
| succeeded, we need to call vlan_dev_free_egress_priority() |
| to free all allocated memory because after a failed ->newlink() |
| we do not call any methods like ndo_uninit() or dev->priv_destructor(). |
| |
| In following example, if the allocation for last element 2000:2001 fails, |
| we need to free eight prior allocations: |
| |
| ip link add link dummy0 dummy0.100 type vlan id 100 \ |
| egress-qos-map 1:2 2:3 3:4 4:5 5:6 6:7 7:8 8:9 2000:2001 |
| |
| syzbot report was: |
| |
| BUG: memory leak |
| unreferenced object 0xffff888117bd1060 (size 32): |
| comm "syz-executor408", pid 3759, jiffies 4294956555 (age 34.090s) |
| hex dump (first 32 bytes): |
| 09 00 00 00 00 a0 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: |
| [<ffffffff83fc60ad>] kmalloc include/linux/slab.h:600 [inline] |
| [<ffffffff83fc60ad>] vlan_dev_set_egress_priority+0xed/0x170 net/8021q/vlan_dev.c:193 |
| [<ffffffff83fc6628>] vlan_changelink+0x178/0x1d0 net/8021q/vlan_netlink.c:128 |
| [<ffffffff83fc67c8>] vlan_newlink+0x148/0x260 net/8021q/vlan_netlink.c:185 |
| [<ffffffff838b1278>] rtnl_newlink_create net/core/rtnetlink.c:3363 [inline] |
| [<ffffffff838b1278>] __rtnl_newlink+0xa58/0xdc0 net/core/rtnetlink.c:3580 |
| [<ffffffff838b1629>] rtnl_newlink+0x49/0x70 net/core/rtnetlink.c:3593 |
| [<ffffffff838ac66c>] rtnetlink_rcv_msg+0x21c/0x5c0 net/core/rtnetlink.c:6089 |
| [<ffffffff839f9c37>] netlink_rcv_skb+0x87/0x1d0 net/netlink/af_netlink.c:2501 |
| [<ffffffff839f8da7>] netlink_unicast_kernel net/netlink/af_netlink.c:1319 [inline] |
| [<ffffffff839f8da7>] netlink_unicast+0x397/0x4c0 net/netlink/af_netlink.c:1345 |
| [<ffffffff839f9266>] netlink_sendmsg+0x396/0x710 net/netlink/af_netlink.c:1921 |
| [<ffffffff8384dbf6>] sock_sendmsg_nosec net/socket.c:714 [inline] |
| [<ffffffff8384dbf6>] sock_sendmsg+0x56/0x80 net/socket.c:734 |
| [<ffffffff8384e15c>] ____sys_sendmsg+0x36c/0x390 net/socket.c:2488 |
| [<ffffffff838523cb>] ___sys_sendmsg+0x8b/0xd0 net/socket.c:2542 |
| [<ffffffff838525b8>] __sys_sendmsg net/socket.c:2571 [inline] |
| [<ffffffff838525b8>] __do_sys_sendmsg net/socket.c:2580 [inline] |
| [<ffffffff838525b8>] __se_sys_sendmsg net/socket.c:2578 [inline] |
| [<ffffffff838525b8>] __x64_sys_sendmsg+0x78/0xf0 net/socket.c:2578 |
| [<ffffffff845ad8d5>] do_syscall_x64 arch/x86/entry/common.c:50 [inline] |
| [<ffffffff845ad8d5>] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 |
| [<ffffffff8460006a>] entry_SYSCALL_64_after_hwframe+0x46/0xb0 |
| |
| The Linux kernel CVE team has assigned CVE-2022-49636 to this issue. |
| |
| |
| Affected and fixed versions |
| =========================== |
| |
| Issue introduced in 5.4.291 with commit b195d229de401377f70c04e0dff93b342464ec8e and fixed in 5.4.292 with commit 549de58dba4bf1b2adc72e9948b9c76fa88be9d2 |
| Issue introduced in 5.10.235 with commit 62d7ad2c191122119c66361ba6d9f04974b51afe and fixed in 5.10.236 with commit df27729a4fe0002dfd80c96fe1c142829c672728 |
| Issue introduced in 5.15.142 with commit 842801181864690fdcde73b017cce4c1353a7083 and fixed in 5.15.180 with commit f5dc10b910bdac523e5947336445a77066c51bf9 |
| Issue introduced in 5.17 with commit 37aa50c539bcbcc01767e515bd170787fcfc0f33 and fixed in 5.18.13 with commit 4c43069bb1097dd6cc1cf0f7c43a36d1f7b3910b |
| Issue introduced in 5.17 with commit 37aa50c539bcbcc01767e515bd170787fcfc0f33 and fixed in 5.19 with commit 72a0b329114b1caa8e69dfa7cdad1dd3c69b8602 |
| |
| 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-2022-49636 |
| 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/8021q/vlan_netlink.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/549de58dba4bf1b2adc72e9948b9c76fa88be9d2 |
| https://git.kernel.org/stable/c/df27729a4fe0002dfd80c96fe1c142829c672728 |
| https://git.kernel.org/stable/c/f5dc10b910bdac523e5947336445a77066c51bf9 |
| https://git.kernel.org/stable/c/4c43069bb1097dd6cc1cf0f7c43a36d1f7b3910b |
| https://git.kernel.org/stable/c/72a0b329114b1caa8e69dfa7cdad1dd3c69b8602 |
