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overlap unfolded stub on Mach-O i386 [SourceForge upx-Bugs-3447184]

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This commit is contained in:
John Reiser 2011-12-02 20:51:13 -08:00
parent 69f66fbe52
commit adf9aa04ce
3 changed files with 1939 additions and 1927 deletions
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3842
src/stub/i386-darwin.macho-entry.h
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File diff suppressed because it is too large Load Diff

22
src/stub/src/i386-darwin.macho-entry.S
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@ -129,6 +129,9 @@ section LEXEC020
#define PAGE_SIZE ( 1<<12)
GAP= 128 // > farthest prefetch; must match ../../p_mach.cpp
NO_LAP= 64 // avoid overlap for folded loader; must match ../../p_mach.cpp
sz_b_info= 12
sz_unc= 0
sz_cpr= 4
@ -136,10 +139,17 @@ sz_b_info= 12
// Decompress the rest of this loader, and jump to it.
unfold:
pop esi // &{ b_info:{sz_unc, sz_cpr, 4{byte}}, compressed_data...}
mov eax,[sz_cpr + esi]
lea edx,[sz_b_info + eax + esi]
push edx // &destination
pop ebx // &{ b_info:{sz_unc, sz_cpr, 4{byte}}, compressed_data...}
mov ecx,[sz_cpr + ebx]
lea esi,[ -1+ sz_b_info + ecx + ebx] // &hi_byte folded original
mov edi,[sz_unc + ebx]
lea edi,[GAP + NO_LAP -1+ sz_b_info + edi + ebx] // &hi_byte folded copy
std; rep movsb // copy descending
lea edx,[GAP + ebx] // &unfolded
mov esi,ebx // &b_info
lea ebx,[1+ edi] // &lo_byte folded copy
push edx // &unfolded code
cld
lodsd
push eax // sz_uncompressed (maximum dstlen for lzma)
@ -151,13 +161,13 @@ unfold:
push eax // sz_compressed (srclen)
lodsd
mov [4*3 + esp],eax // last 4 bytes of b_info
push esi // &compressed_data
push ebx // &copied_compressed_data
call ebp // decompress(&src, srclen, &dst, &dstlen, b_info.misc)
add esp, (5+1)*4 // (5+1) args to decompress
lea ebx,[-4+ _start - decompress + ebp] // &total_length
ret // &destination
main:
pop ebp // &decompress
lea ebx,[-4+ _start - decompress + ebp] // &total_length
call unfold
// compressed fold_elf86 follows

2
src/stub/tmp/i386-darwin.macho-entry.bin.dump
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@ -169,7 +169,7 @@ Idx Name Size VMA LMA File off Algn Flags
164 CTBSWA11 00000005 00000000 00000000 00001ab0 2**0 CONTENTS, READONLY
165 CALLTR13 00000007 00000000 00000000 00001ab5 2**0 CONTENTS, RELOC, READONLY
166 LEXEC017 00000002 00000000 00000000 00001abc 2**0 CONTENTS, READONLY
167 LEXEC020 00000028 00000000 00000000 00001abe 2**0 CONTENTS, READONLY
167 LEXEC020 0000003f 00000000 00000000 00001abe 2**0 CONTENTS, READONLY
SYMBOL TABLE:
00000000 l d N2BSMA10 00000000 N2BSMA10
00000000 l d N2BFAS11 00000000 N2BFAS11