CVE-2024-58084

In the Linux kernel, the following vulnerability has been resolved:<br /> <br /> firmware: qcom: scm: Fix missing read barrier in qcom_scm_get_tzmem_pool()<br /> <br /> Commit 2e4955167ec5 ("firmware: qcom: scm: Fix __scm and waitq<br /> completion variable initialization") introduced a write barrier in probe<br /> function to store global &amp;#39;__scm&amp;#39; variable. We all known barriers are<br /> paired (see memory-barriers.txt: "Note that write barriers should<br /> normally be paired with read or address-dependency barriers"), therefore<br /> accessing it from concurrent contexts requires read barrier. Previous<br /> commit added such barrier in qcom_scm_is_available(), so let&amp;#39;s use that<br /> directly.<br /> <br /> Lack of this read barrier can result in fetching stale &amp;#39;__scm&amp;#39; variable<br /> value, NULL, and dereferencing it.<br /> <br /> Note that barrier in qcom_scm_is_available() satisfies here the control<br /> dependency.