CVE-2024-58084 Information

Description

In the Linux kernel the following vulnerability has been resolved:

firmware: qcom: scm: Fix missing read barrier in qcom_scm_get_tzmem_pool()

Commit 2e4955167ec5 (irmware: qcom: scm: Fix __scm and waitq completion variable initialization) introduced a write barrier in probe function to store global ‘__scm’ variable. We all known barriers are paired (see memory-barriers.txt: \Note that write barriers should normally be paired with read or address-dependency barriers) therefore accessing it from concurrent contexts requires read barrier. Previous commit added such barrier in qcom_scm_is_available() so let’s use that directly.

Lack of this read barrier can result in fetching stale ‘__scm’ variable value NULL and dereferencing it.

Note that barrier in qcom_scm_is_available() satisfies here the control dependency.

Reference

https://git.kernel.org/stable/c/b628510397b5cafa1f5d3e848a28affd1c635302 https://git.kernel.org/stable/c/e03db7c1255ebabba5e1a447754faeb138de15a2 https://git.kernel.org/stable/c/fee921e3c641f64185abee83f9a6e65f0b380682