Description (CNA)
In the Linux kernel, the following vulnerability has been resolved: macvlan: fix error recovery in macvlan_common_newlink() valis provided a nice repro to crash the kernel: ip link add p1 type veth peer p2 ip link set address 00:00:00:00:00:20 dev p1 ip link set up dev p1 ip link set up dev p2 ip link add mv0 link p2 type macvlan mode source ip link add invalid% link p2 type macvlan mode source macaddr add 00:00:00:00:00:20 ping -c1 -I p1 1.2.3.4 He also gave a very detailed analysis: <quote valis> The issue is triggered when a new macvlan link is created with MACVLAN_MODE_SOURCE mode and MACVLAN_MACADDR_ADD (or MACVLAN_MACADDR_SET) parameter, lower device already has a macvlan port and register_netdevice() called from macvlan_common_newlink() fails (e.g. because of the invalid link name). In this case macvlan_hash_add_source is called from macvlan_change_sources() / macvlan_common_newlink(): This adds a reference to vlan to the port's vlan_source_hash using macvlan_source_entry. vlan is a pointer to the priv data of the link that is being created. When register_netdevice() fails, the error is returned from macvlan_newlink() to rtnl_newlink_create(): if (ops->newlink) err = ops->newlink(dev, ¶ms, extack); else err = register_netdevice(dev); if (err < 0) { free_netdev(dev); goto out; } and free_netdev() is called, causing a kvfree() on the struct net_device that is still referenced in the source entry attached to the lower device's macvlan port. Now all packets sent on the macvlan port with a matching source mac address will trigger a use-after-free in macvlan_forward_source(). </quote valis> With all that, my fix is to make sure we call macvlan_flush_sources() regardless of @create value whenever "goto destroy_macvlan_port;" path is taken. Many thanks to valis for following up on this issue.
Affected (CNA)
| Vendor / product | Versions |
|---|---|
| Linux / Linux | affected aa5fd0fb77486b8a6764ead8627baa14790e4280 before da5c6b8ae47e414be47e5e04def15b25d5c962dc; affected aa5fd0fb77486b8a6764ead8627baa14790e4280 before 5dae6b36a7cb7a4fcf4121b95e9ca7f96f816c8a; affected aa5fd0fb77486b8a6764ead8627baa14790e4280 before c43d0e787cbba569ec9d11579ed370b50fab6c9c; affected aa5fd0fb77486b8a6764ead8627baa14790e4280 before 11ba9f0dc865136174cb98834280fb21bbc950c7; affected aa5fd0fb77486b8a6764ead8627baa14790e4280 before 986967a162142710076782d5b93daab93a892980; affected aa5fd0fb77486b8a6764ead8627baa14790e4280 before cdedcd5aa3f3cb8b7ae0f87ab3a936d0bd583d66; affected aa5fd0fb77486b8a6764ead8627baa14790e4280 before f8db6475a83649689c087a8f52486fcc53e627e9 |
| Linux / Linux | affected 4.9; unaffected 0 before 4.9; unaffected 5.10.250 through 5.10.*; unaffected 5.15.200 through 5.15.*; unaffected 6.1.163 through 6.1.*; unaffected 6.6.124 through 6.6.*; unaffected 6.12.70 through 6.12.*; unaffected 6.18.10 through 6.18.*; unaffected 6.19 through * |
CWE
No CWE identifiers supplied.
References
- https://git.kernel.org/stable/c/da5c6b8ae47e414be47e5e04def15b25d5c962dc
- https://git.kernel.org/stable/c/5dae6b36a7cb7a4fcf4121b95e9ca7f96f816c8a
- https://git.kernel.org/stable/c/c43d0e787cbba569ec9d11579ed370b50fab6c9c
- https://git.kernel.org/stable/c/11ba9f0dc865136174cb98834280fb21bbc950c7
- https://git.kernel.org/stable/c/986967a162142710076782d5b93daab93a892980
- https://git.kernel.org/stable/c/cdedcd5aa3f3cb8b7ae0f87ab3a936d0bd583d66
- https://git.kernel.org/stable/c/f8db6475a83649689c087a8f52486fcc53e627e9
ADP enrichment
No English description supplied.
No references supplied.