Source: nsis Version: 3.03-2 Severity: important Tags: ftbfs User: [email protected] Usertags: alignment
Hi! I've been doing a full rebuild of the Debian archive, building all source packages targeting armel and armhf using arm64 hardware. We are planning in future to move all of our 32-bit armel/armhf builds to using arm64 machines, so this rebuild is to identify packages that might have problems with this configuration. A feature of the arm64 kernel is that it does *not* support fixing up code with broken alignment, so code that might have built and run OK on our older armel/armhf build machines due to kernel fixups will now fail. When building your package, I've found a bus error (aka alignment fault). The full log is online at https://www.einval.com/debian/arm/rebuild-logs/armhf/FAIL/nsis_3.03-2_armhf.log for reference I've done a quick bit of debugging to find the source of the bug. Here's a gdb stacktrace and variable printout to demonstrate the problem. (sid-armhf)steve@mjolnir:~/debian/build/nsis/nsis-3.03$ gdb build/test/usr/bin/makensis build/test/usr/share/doc/nsis/Examples/core ... Reading symbols from build/test/usr/bin/makensis...done. [New LWP 14637] [Thread debugging using libthread_db enabled] Using host libthread_db library "/lib/arm-linux-gnueabihf/libthread_db.so.1". Core was generated by `/home/steve/debian/build/nsis/nsis-3.03/build/test/usr/bin/makensis /home/steve'. Program terminated with signal SIGBUS, Bus error. #0 0x009ca7a8 in generate_uninstall_icon_data (icon1=..., icon2=..., data_size=@0xffc4cf28: 1102) at Source/icon.cpp:373 373 DWORD size = FIX_ENDIAN_INT32(icon->meta.dwRawSize); (gdb) bt #0 0x009ca7a8 in generate_uninstall_icon_data (icon1=std::vector of length 2, capacity 2 = {...}, icon2=std::vector of length 2, capacity 2 = {...}, data_size=@0xffc4cf28: 1102) at Source/icon.cpp:373 #1 0x009c4e36 in CEXEBuild::uninstall_generate (this=this@entry=0xffc38218) at /usr/include/c++/8/ext/new_allocator.h:99 #2 0x009c5610 in CEXEBuild::write_output (this=0xffc38218) at Source/build.cpp:2639 #3 0x009ce7d4 in makensismain (argc=3, argv=0x13e5058) at Source/makenssi.cpp:669 #4 0x009bb970 in wmain (argv=0x13e5058, argc=3) at Source/makenssi.cpp:695 #5 main (argc=3, argv=<optimized out>) at Source/makenssi.cpp:719 (gdb) list 368 369 // fill entries 370 for (i = 0; i < icon2.size(); i++) 371 { 372 Icon* icon = &icon2[order[i].index2]; 373 DWORD size = FIX_ENDIAN_INT32(icon->meta.dwRawSize); 374 375 *(LPDWORD) seeker = FIX_ENDIAN_INT32(size); 376 seeker += sizeof(DWORD); 377 *(LPDWORD) seeker = 0; (gdb) p i $1 = 0 (gdb) p order[i] $2 = {index1 = 1, index2 = 1, size = 744, size_index = 0} (gdb) p *icon2 No symbol "operator*" in current context. (gdb) p icon2 $3 = std::vector of length 2, capacity 2 = {{index = 0, meta = {bWidth = 16 '\020', bHeight = 16 '\020', bPaletteEntries = 16 '\020', bReserved = 0 '\000', wPlanes = 0, wBitsPerPixel = 0, dwRawSize = 296}, data = 0x1473530 "("}, {index = 1, meta = {bWidth = 32 ' ', bHeight = 32 ' ', bPaletteEntries = 16 '\020', bReserved = 0 '\000', wPlanes = 0, wBitsPerPixel = 0, dwRawSize = 744}, data = 0x142b070 "("}} (gdb) p order[i].index2 $4 = 1 (gdb) p icon2[1] $5 = {index = 1, meta = {bWidth = 32 ' ', bHeight = 32 ' ', bPaletteEntries = 16 '\020', bReserved = 0 '\000', wPlanes = 0, wBitsPerPixel = 0, dwRawSize = 744}, data = 0x142b070 "("} (gdb) p &icon2[1] $6 = (Icon *) 0x1496c1c (gdb) p &icon2[1].meta $7 = (IconGroupEntry *) 0x1496c20 (gdb) p &icon2[1].meta.dwRawSize $8 = (DWORD *) 0x1496c28 (gdb) p seeker $9 = (LPBYTE) 0x1494bfa "" (gdb) p *seeker $10 = 0 '\000' I think gdb is maybe mis-identifying the exact source line for the crash. Line 373 looks OK, with all the reading aligned correctly. However, in line 375 the pointer "seeker" is clearly not safely aligned for storing a DWORD. -- System Information: Debian Release: 9.6 APT prefers stable-updates APT policy: (500, 'stable-updates'), (500, 'stable-debug'), (500, 'stable') Architecture: amd64 (x86_64) Foreign Architectures: i386 Kernel: Linux 4.9.0-8-amd64 (SMP w/4 CPU cores) Locale: LANG=en_GB.UTF-8, LC_CTYPE=en_GB.UTF-8 (charmap=UTF-8), LANGUAGE=en_GB.UTF-8 (charmap=UTF-8) Shell: /bin/sh linked to /bin/dash Init: systemd (via /run/systemd/system)
