CVE-2021-46904 (GCVE-0-2021-46904)
Vulnerability from cvelistv5
Published
2024-02-25 14:03
Modified
2026-05-11 13:44
Severity ?
Summary
In the Linux kernel, the following vulnerability has been resolved: net: hso: fix null-ptr-deref during tty device unregistration Multiple ttys try to claim the same the minor number causing a double unregistration of the same device. The first unregistration succeeds but the next one results in a null-ptr-deref. The get_free_serial_index() function returns an available minor number but doesn't assign it immediately. The assignment is done by the caller later. 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 number immediately 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 the given hso_serial. Every obtain_minor() should have corresponding release_minor() call.
References
Impacted products
Vendor Product Version
Linux Linux Version: 72dc1c096c7051a48ab1dbb12f71976656b55eb5
Version: 72dc1c096c7051a48ab1dbb12f71976656b55eb5
Version: 72dc1c096c7051a48ab1dbb12f71976656b55eb5
Version: 72dc1c096c7051a48ab1dbb12f71976656b55eb5
Version: 72dc1c096c7051a48ab1dbb12f71976656b55eb5
Version: 72dc1c096c7051a48ab1dbb12f71976656b55eb5
Version: 72dc1c096c7051a48ab1dbb12f71976656b55eb5
Version: 72dc1c096c7051a48ab1dbb12f71976656b55eb5
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