CVE-2024-50203

In the Linux kernel, the following vulnerability has been resolved:

bpf, arm64: Fix address emission with tag-based KASAN enabled

When BPFTRAMPFCALLORIG is enabled, the address of a bpftrampimage struct on the stack is passed during the size calculation pass and an address on the heap is passed during code generation. This may cause a heap buffer overflow if the heap address is tagged because emita64movi64() will emit longer code than it did during the size calculation pass. The same problem could occur without tag-based KASAN if one of the 16-bit words of the stack address happened to be all-ones during the size calculation pass. Fix the problem by assuming the worst case (4 instructions) when calculating the size of the bpftramp_image address emission.