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Correct memory size calculation for modules on linux #255

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Merged
Kenzzer merged 3 commits into from
Jan 11, 2026
Merged

Correct memory size calculation for modules on linux #255

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Correct memory size calculation for modules on linux
Kenzzer Jan 9, 2026
74d34c4
Review change
Kenzzer Jan 10, 2026
13fec1a
Review changes
Kenzzer Jan 10, 2026
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28 changes: 16 additions & 12 deletions loader/utility.cpp
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Original file line number Diff line number Diff line change
Expand Up @@ -502,24 +502,28 @@ mm_GetLibraryInfo(const void *libPtr, DynLibInfo &lib)
phdrCount = file->e_phnum;
phdr = reinterpret_cast<ElfPHeader *>(baseAddr + file->e_phoff);

lib.memorySize = 0;
size_t minAddr = SIZE_MAX, maxAddr = 0;
for (uint16_t i = 0; i < phdrCount; i++)
{
ElfPHeader &hdr = phdr[i];

/* We only really care about the segment with executable code */
if (hdr.p_type == PT_LOAD && hdr.p_flags == (PF_X|PF_R))
if (hdr.p_type == PT_LOAD)
{
/* From glibc, elf/dl-load.c:
* c->mapend = ((ph->p_vaddr + ph->p_filesz + GLRO(dl_pagesize) - 1)
* & ~(GLRO(dl_pagesize) - 1));
*
* In glibc, the segment file size is aligned up to the nearest page size and
* added to the virtual address of the segment. We just want the size here.
*/
lib.memorySize = PAGE_ALIGN_UP(hdr.p_filesz);
break;
if (hdr.p_vaddr < minAddr)
{
minAddr = hdr.p_vaddr;
}
if ((hdr.p_vaddr + hdr.p_memsz) > maxAddr)
{
maxAddr = hdr.p_vaddr + hdr.p_memsz;
}
}
}
if (minAddr > maxAddr)
{
return false;
}
lib.memorySize = maxAddr - minAddr;
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#elif defined __APPLE__

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