CVE-2022-49804

In the Linux kernel, the following vulnerability has been resolved:<br /> <br /> s390: avoid using global register for current_stack_pointer<br /> <br /> Commit 30de14b1884b ("s390: current_stack_pointer shouldn&amp;#39;t be a<br /> function") made current_stack_pointer a global register variable like<br /> on many other architectures. Unfortunately on s390 it uncovers old<br /> gcc bug which is fixed only since gcc-9.1 [gcc commit 3ad7fed1cc87<br /> ("S/390: Fix PR89775. Stackpointer save/restore instructions removed")]<br /> and backported to gcc-8.4 and later. Due to this bug gcc versions prior<br /> to 8.4 generate broken code which leads to stack corruptions.<br /> <br /> Current minimal gcc version required to build the kernel is declared<br /> as 5.1. It is not possible to fix all old gcc versions, so work<br /> around this problem by avoiding using global register variable for<br /> current_stack_pointer.