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[libunwind] Fix wrong end argument passed to decodeEHHdr() (#68813)

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All but one callsite were actually passing start+length arguments.
This should not have any functional change since the end argument is
almost always ignored.
I noticed this while debugging some incorrect error messages being
printed while running the testsuite baremetal (using binaries that did
not have a valid eh_frame_hdr section): the tests print
`libunwind: unsupported .eh_frame_hdr version: 20 at
8000d30814`
because
libunwind is reading nonsense data for .eh_frame_hdr.
This commit is contained in:
Alexander Richardson 2023-10-11 11:35:11 -07:00 committed by GitHub
parent 325576196b
commit 05181a849b
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GPG Key ID: 4AEE18F83AFDEB23
1 changed files with 4 additions and 3 deletions
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7
libunwind/src/AddressSpace.hpp
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@ -414,8 +414,8 @@ static bool checkForUnwindInfoSegment(const Elf_Phdr *phdr, size_t image_base,
cbdata->sects->dwarf_index_section = eh_frame_hdr_start;
cbdata->sects->dwarf_index_section_length = phdr->p_memsz;
if (EHHeaderParser<LocalAddressSpace>::decodeEHHdr(
*cbdata->addressSpace, eh_frame_hdr_start, phdr->p_memsz,
hdrInfo)) {
*cbdata->addressSpace, eh_frame_hdr_start,
eh_frame_hdr_start + phdr->p_memsz, hdrInfo)) {
// .eh_frame_hdr records the start of .eh_frame, but not its size.
// Rely on a zero terminator to find the end of the section.
cbdata->sects->dwarf_section = hdrInfo.eh_frame_ptr;
@ -638,7 +638,8 @@ inline bool LocalAddressSpace::findUnwindSections(pint_t targetAddr,
info.dwarf_index_section_length = SIZE_MAX;
EHHeaderParser<LocalAddressSpace>::EHHeaderInfo hdrInfo;
if (!EHHeaderParser<LocalAddressSpace>::decodeEHHdr(
*this, info.dwarf_index_section, info.dwarf_index_section_length,
*this, info.dwarf_index_section,
info.dwarf_index_section + info.dwarf_index_section_length,
hdrInfo)) {
return false;
}