CVE-2022-49853

About vulnerability

In the Linux kernel, the following vulnerability has been resolved:

net: macvlan: fix memory leaks of macvlan_common_newlink

kmemleak reports memory leaks in macvlan_common_newlink, as follows:

ip link add link eth0 name .. type macvlan mode source macaddr add

kmemleak reports:

unreferenced object 0xffff8880109bb140 (size 64): comm “ip”, pid 284, jiffies 4294986150 (age 430.108s) hex dump (first 32 bytes): 00 00 00 00 00 00 00 00 b8 aa 5a 12 80 88 ff ff ……….Z….. 80 1b fa 0d 80 88 ff ff 1e ff ac af c7 c1 6b 6b …………..kk backtrace: [] kmem_cache_alloc_trace+0x1c7/0x300 [] macvlan_hash_add_source+0x45/0xc0 [] macvlan_changelink_sources+0xd7/0x170 [] macvlan_common_newlink+0x38c/0x5a0 [] macvlan_newlink+0xe/0x20 [] __rtnl_newlink+0x7af/0xa50 [] rtnl_newlink+0x48/0x70 …

In the scenario where the macvlan mode is configured as ‘source’, macvlan_changelink_sources() will be execured to reconfigure list of remote source mac addresses, at the same time, if register_netdevice() return an error, the resource generated by macvlan_changelink_sources() is not cleaned up.

Using this patch, in the case of an error, it will execute macvlan_flush_sources() to ensure that the resource is cleaned up.

Affected product:

AlmaLinux 9.2 ESU , CentOS 8.4 ELS , CentOS 8.5 ELS , CentOS Stream 8 ELS , Oracle Linux 7 ELS , TuxCare 9.6 ESU , Ubuntu 16.04 ELS , Ubuntu 18.04 ELS , Ubuntu 20.04 ELS

Affected packages:

kernel @ 4.18.0 (+8 more)

In the Linux kernel, the following vulnerability has been resolved:

net: macvlan: fix memory leaks of macvlan_common_newlink

kmemleak reports memory leaks in macvlan_common_newlink, as follows:

ip link add link eth0 name .. type macvlan mode source macaddr add

kmemleak reports:

unreferenced object 0xffff8880109bb140 (size 64): comm “ip”, pid 284, jiffies 4294986150 (age 430.108s) hex dump (first 32 bytes): 00 00 00 00 00 00 00 00 b8 aa 5a 12 80 88 ff ff ……….Z….. 80 1b fa 0d 80 88 ff ff 1e ff ac af c7 c1 6b 6b …………..kk backtrace: [] kmem_cache_alloc_trace+0x1c7/0x300 [] macvlan_hash_add_source+0x45/0xc0 [] macvlan_changelink_sources+0xd7/0x170 [] macvlan_common_newlink+0x38c/0x5a0 [] macvlan_newlink+0xe/0x20 [] __rtnl_newlink+0x7af/0xa50 [] rtnl_newlink+0x48/0x70 …

In the scenario where the macvlan mode is configured as ‘source’, macvlan_changelink_sources() will be execured to reconfigure list of remote source mac addresses, at the same time, if register_netdevice() return an error, the resource generated by macvlan_changelink_sources() is not cleaned up.

Using this patch, in the case of an error, it will execute macvlan_flush_sources() to ensure that the resource is cleaned up.