[compiler-rt] [Sanitizers][Apple] Fix logic bugs that break RestrictMemoryToMaxAddress (PR #124712)

[Julian Lettner via llvm-commits]

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@@ -1272,10 +1272,11 @@ uptr FindAvailableMemoryRange(uptr size, uptr alignment, uptr left_padding,
     mach_msg_type_number_t count = kRegionInfoSize;
     kr = mach_vm_region_recurse(mach_task_self(), &address, &vmsize, &depth,
                                 (vm_region_info_t)&vminfo, &count);
-    if (kr == KERN_INVALID_ADDRESS) {
+    if (kr == KERN_INVALID_ADDRESS || address > max_vm_address) {
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yln wrote:

Currently, if `mach_vm_region_recurse()` ever returns an error different from `KERN_INVALID_ADDRESS` (I don't think it currently does except if the arguments are wrong, then `KERN_INVALID_ARGUMENT`), then we would still treat the result "successful enough" to update `max_occupied_addr`.  Is that the intention?

https://github.com/llvm/llvm-project/pull/124712