概要

In the Linux kernel, the following vulnerability has been resolved:net: hso: fix null-ptr-deref during tty device unregistrationMultiple ttys try to claim the same the minor number causing a doubleunregistration of the same device. The first unregistration succeedsbut the next one results in a null-ptr-deref.The get_free_serial_index() function returns an available minor numberbut doesn t assign it immediately. The assignment is done by the callerlater. But before this assignment, calls to get_free_serial_index()would return the same minor number.Fix this by modifying get_free_serial_index to assign the minor numberimmediately after one is found to be and rename it to obtain_minor()to better reflect what it does. Similary, rename set_serial_by_index()to release_minor() and modify it to free up the minor number of thegiven hso_serial. Every obtain_minor() should have correspondingrelease_minor() call.

CVSS v3 指标

安全公告

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