cve-2021-47517
Vulnerability from cvelistv5
Published
2024-05-24 15:09
Modified
2024-12-19 07:44
Severity ?
Summary
In the Linux kernel, the following vulnerability has been resolved: ethtool: do not perform operations on net devices being unregistered There is a short period between a net device starts to be unregistered and when it is actually gone. In that time frame ethtool operations could still be performed, which might end up in unwanted or undefined behaviours[1]. Do not allow ethtool operations after a net device starts its unregistration. This patch targets the netlink part as the ioctl one isn't affected: the reference to the net device is taken and the operation is executed within an rtnl lock section and the net device won't be found after unregister. [1] For example adding Tx queues after unregister ends up in NULL pointer exceptions and UaFs, such as: BUG: KASAN: use-after-free in kobject_get+0x14/0x90 Read of size 1 at addr ffff88801961248c by task ethtool/755 CPU: 0 PID: 755 Comm: ethtool Not tainted 5.15.0-rc6+ #778 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.14.0-4.fc34 04/014 Call Trace: dump_stack_lvl+0x57/0x72 print_address_description.constprop.0+0x1f/0x140 kasan_report.cold+0x7f/0x11b kobject_get+0x14/0x90 kobject_add_internal+0x3d1/0x450 kobject_init_and_add+0xba/0xf0 netdev_queue_update_kobjects+0xcf/0x200 netif_set_real_num_tx_queues+0xb4/0x310 veth_set_channels+0x1c3/0x550 ethnl_set_channels+0x524/0x610
References
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/7c26da3be1e9843a15b5318f90db8a564479d2ac
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/cfd719f04267108f5f5bf802b9d7de69e99a99f9
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/dde91ccfa25fd58f64c397d91b81a4b393100ffa
af854a3a-2127-422b-91ae-364da2661108https://git.kernel.org/stable/c/7c26da3be1e9843a15b5318f90db8a564479d2ac
af854a3a-2127-422b-91ae-364da2661108https://git.kernel.org/stable/c/cfd719f04267108f5f5bf802b9d7de69e99a99f9
af854a3a-2127-422b-91ae-364da2661108https://git.kernel.org/stable/c/dde91ccfa25fd58f64c397d91b81a4b393100ffa
Impacted products
Vendor Product Version
Linux Linux Version: 5.6
Show details on NVD website

To clipboard 

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}


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