net: arp: terminate device name before lookup

Overview

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

net: arp: terminate device name before lookup

The ARP ioctl copies a user-provided struct arpreq into a stack object. Its arp_dev field may contain IFNAMSIZ bytes without a NUL terminator.

Such input is passed to dev_get_by_name_rcu() or __dev_get_by_name(), where strcmp() can read past the end of the stack object when a matching alternative interface name exists.

Terminate the field before the lookup to prevent the out-of-bounds read.

Affected

• Linux >= 36fbf1e52bd3ff8a5cb604955eedfc9350c2e6cc < ae6d704dbf9542b0a0830ec91a2db4f30307e7d8
• Linux >= 36fbf1e52bd3ff8a5cb604955eedfc9350c2e6cc < 47107491b48ceef0a2faa7a010cfa961f211ef9f
• Linux >= 36fbf1e52bd3ff8a5cb604955eedfc9350c2e6cc < 7389757d88f54237951d7497d9c4dae7cc6d64be
• Linux >= 36fbf1e52bd3ff8a5cb604955eedfc9350c2e6cc < 1b08c5c3ac27c9ff91c5309f4a32b4e91ce2263b
• Linux >= 36fbf1e52bd3ff8a5cb604955eedfc9350c2e6cc < 414bbad9928598904313299ac9e037a73f520be1
• Linux >= 36fbf1e52bd3ff8a5cb604955eedfc9350c2e6cc < ba664d83638640cf454b65167339cbf20dfd6f10
• Linux >= 36fbf1e52bd3ff8a5cb604955eedfc9350c2e6cc < 35e716a70733472ede300540082d64c33bf3b4c9
• Linux >= 36fbf1e52bd3ff8a5cb604955eedfc9350c2e6cc < d8b6529e80bcb4fb8177121404cbb3377acaebd2
• Linux 5.5

Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.