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WinPE with TLS: fix relocation bugs

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--strip-relocs not needed after bugfixes, but keep safety check.
Thanks to @ml1050.
https://github.com/upx/upx/issues/880
	modified:   pefile.cpp
This commit is contained in:
John Reiser 2025-10-26 13:36:43 -07:00 committed by Markus F.X.J. Oberhumer
parent 09d7d08e55
commit 3068d19492
1 changed files with 11 additions and 5 deletions
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16
src/pefile.cpp
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@ -1487,23 +1487,29 @@ void PeFile::processTls2(Reloc *const rel, const Interval *const iv, unsigned ne
unsigned ic;
// NEW: if TLS callbacks are used, relocate the VA of the callback chain, too - Stefan Widmann
for (ic = 0; ic < (use_tls_callbacks ? sizeof(LE32) * cb_size : (sizeof(LE32) - 1) * cb_size);
ic += cb_size)
rel->add_reloc(newaddr + ic, reloc_type);
for (ic = 0; ic < (unsigned) (use_tls_callbacks ? 4 : 3); ic++)
rel->add_reloc(newaddr + ic * cb_size, reloc_type);
SPAN_S_VAR(tls, const tlsp, mb_otls);
// now the relocation entries in the tls data area
for (ic = 0; ic < iv->ivnum; ic += sizeof(LE32)) {
for (ic = 0; ic < iv->ivnum; ic++) {
SPAN_S_VAR(byte, const pp,
otls + (iv->ivarr[ic].start - (tlsp->datastart - imagebase) + sizeof(tls)));
LEXX *const p = (LEXX *) raw_bytes(pp, sizeof(LEXX));
cb_value_t kc = *p;
if (kc < tlsp->dataend && kc >= tlsp->datastart) {
// add a relocation entry referring to an address inside of the original tls data area
// - as the new tls area is moved, the referred address have to be also adjusted
kc += newaddr + sizeof(tls) - tlsp->datastart;
*p = kc + imagebase;
rel->add_reloc(kc, iv->ivarr[ic].len);
} else {
unsigned const a = kc - imagebase;
// add a relocation entry referring to an address outside of the original tls data area
// by adding the difference of the new tlsdatastart and the old tlsdatastart to
// the address of the original relocation record
unsigned const a =
iv->ivarr[ic].start + (newaddr + sizeof(tls)) - (tlsp->datastart - imagebase);
// Must not overwrite compressed data
if (a < newaddr && !opt->win32_pe.strip_relocs)
throwCantPack("relocation too low (%#x < %#x); try --strip-relocs", a, newaddr);
rel->add_reloc(a, iv->ivarr[ic].len);