CVE-2023-53184

In the Linux kernel, the following vulnerability has been resolved:<br /> <br /> arm64/sme: Set new vector length before reallocating<br /> <br /> As part of fixing the allocation of the buffer for SVE state when changing<br /> SME vector length we introduced an immediate reallocation of the SVE state,<br /> this is also done when changing the SVE vector length for consistency.<br /> Unfortunately this reallocation is done prior to writing the new vector<br /> length to the task struct, meaning the allocation is done with the old<br /> vector length and can lead to memory corruption due to an undersized buffer<br /> being used.<br /> <br /> Move the update of the vector length before the allocation to ensure that<br /> the new vector length is taken into account.<br /> <br /> For some reason this isn&amp;#39;t triggering any problems when running tests on<br /> the arm64 fixes branch (even after repeated tries) but is triggering<br /> issues very often after merge into mainline.