IT

Tracker / CVE-2021-47334

CVE-2021-47334

High 7.8

In the Linux kernel, the following vulnerability has been resolved: misc/libmasm/module: Fix two use after free in ibmasm_init_one In ibmasm_init_one, it calls ibmasm_init_remote_input_dev(). Inside ibmasm_init_remote_input_dev, mouse_dev and keybd_dev are allocated by input_allocate_device(), and assigned to sp->remote.mouse_dev and sp->remote.keybd_dev respectively. In the err_free_devices error branch of ibmasm_init_one, mouse_dev and keybd_dev are freed by input_free_device(), and return error. Then the execution runs into error_send_message error branch of ibmasm_init_one, where ibmasm_free_remote_input_dev(sp) is called to unregister the freed sp->remote.mouse_dev and sp->remote.keybd_dev. My patch add a "error_init_remote" label to handle the error of ibmasm_init_remote_input_dev(), to avoid the uaf bugs.

Affected products and versions

linux linux_kernel · … → 4.4.276
linux linux_kernel · 4.10 → 4.14.240
linux linux_kernel · 4.15 → 4.19.198
linux linux_kernel · 4.20 → 5.4.134
linux linux_kernel · 4.5 → 4.9.276
linux linux_kernel · 5.11 → 5.12.19
linux linux_kernel · 5.13 → 5.13.4
linux linux_kernel · 5.5 → 5.10.52

Analysis

This page is not indexable yet.Until it carries original analysis — what it actually exposes, how to check in two minutes whether a system was touched, what to do if it was — the page stays noindex. The database decides that, not the template.

References