Hi Marc, works like a charm! Michael 2017-05-15 16:33 GMT+02:00 Marc Stevens <marc@xxxxxxxxxxxxxxx>: > Hi Michael, > > > > See the latest commit to the SHA1DC repo: > > https://github.com/cr-marcstevens/sha1collisiondetection/commit/33a694a9ee1b79c24be45f9eab5ac0e1aeeaf271 > > Just apply this same patch to SHA1DC in Git. > > > > Best regards, > > Marc Stevens > > > > Van: Michael Kebe [mailto:michael.kebe@xxxxxxxxx] > Verzonden: maandag 15 mei 2017 16:22 > Aan: Ævar Arnfjörð Bjarmason <avarab@xxxxxxxxx> > CC: Jeff King <peff@xxxxxxxx>; Git Mailing List <git@xxxxxxxxxxxxxxx>; Marc > Stevens <marc@xxxxxxxxxxxxxxx> > Onderwerp: Re: Git 2.13.0 segfaults on Solaris SPARC due to > DC_SHA1=YesPlease being on by default > > > > Just give me patch or repo, I will test it tomorrow. > > > > Michael > > > > > > Am 15.05.2017 4:14 nachm. schrieb "Ævar Arnfjörð Bjarmason" > <avarab@xxxxxxxxx>: > > On Mon, May 15, 2017 at 3:58 PM, Marc Stevens <marc@xxxxxxxxxxxxxxx> wrote: >> Hi Aevar, >> >> Thank you for notifying us of this issue. >> Big endianness is a tricky issue, also since I don't have access or >> accurate knowledge about all big endian systems. >> Our github repo does check correct functioning, including an endianness >> mistake, with 'make test'. >> But I guess this is not included for SHA1DC in Git. >> >> Anyway, we can easily add the _BIG_ENDIAN macrotest to the git repo and >> will do so soon. >> >> I don't think the segfault is caused by buffer overflow, inproper access, >> or the endianness issue. >> But I did notice an unexpected issue: the message block pointer m=0x398ad5 >> is odd. >> Can you confirm whether loading an uint32_t from an odd address triggers a >> hardware interrupt on your platform? >> This is not problem for x86, but maybe for your platform it is? >> If it is then we should always copy buffer contents to the sha1context to >> avoid this issue. > > I don't have access to the box in question, Michael was testing this > code for me. But unaligned access is probably the cause, although > according to some info I found online that should give a SIGBUS not a > SIGSEGV, but that may have changed: > > https://bugs.python.org/issue12181 > https://github.com/magnumripper/JohnTheRipper/issues/2187 > >> Best regards, >> Marc Stevens >> >> -----Oorspronkelijk bericht----- >> Van: Ævar Arnfjörð Bjarmason [mailto:avarab@xxxxxxxxx] >> Verzonden: maandag 15 mei 2017 14:49 >> Aan: Git Mailing List <git@xxxxxxxxxxxxxxx> >> CC: michael.kebe@xxxxxxxxx; Jeff King <peff@xxxxxxxx>; Marc Stevens >> <marc@xxxxxxxxxxxxxxx> >> Onderwerp: Git 2.13.0 segfaults on Solaris SPARC due to DC_SHA1=YesPlease >> being on by default >> >> Since 2.13.0 just running "git status" on a newly init'd repo on Solaris >> SPARC[1] segfaults. Michael (CC'd) reported this issue on #git and I helped >> him debug it. >> >> Just compiling with BLK_SHA1=YesPlease solves the issue. >> >> There are at least two different issues with DC_SHA1 here: >> >> * We don't properly detect that this platform is big endian. The check at >> the top of sha1dc/sha1.c needs to test for _BIG_ENDIAN. This comes from >> sys/isa_defs.h which (I'm told by #solaris) is included on Solaris by >> default, at least by stdio.h. >> >> Hacking the endian detection makes t0013-sha1dc.sh pass. >> >> * Even with that & the test passing just a plain "git init x && cd x && >> touch A && git add A && git commit" will segfault. >> >> This is some bug in the sha1dc code, presumably some big endian issue >> that's not resolved by the change above. Backtrace for that (censored actual >> author info): >> >> Program received signal SIGSEGV, Segmentation fault. >> [Switching to Thread 1 (LWP 1)] >> 0x002f8c84 in sha1_compression_states (ihv=0xffbf8268, m=0x398ad5, >> W=0xffbf82fc, states=0xffbf857c) at sha1dc/sha1.c:291 >> 291 SHA1COMPRESS_FULL_ROUND1_STEP_LOAD(a, b, c, d, e, m, >> W, 0, temp); >> (gdb) bt >> #0 0x002f8c84 in sha1_compression_states (ihv=0xffbf8268, m=0x398ad5, >> W=0xffbf82fc, states=0xffbf857c) at sha1dc/sha1.c:291 >> #1 0x00300b60 in sha1_process (ctx=0xffbf8260, block=0x398ad5) at >> sha1dc/sha1.c:1616 >> #2 0x00301188 in SHA1DCUpdate (ctx=0xffbf8260, >> buf=0x398ad5 "deadbeefdeadbeefdeadbeefdeadbeefdeadbeef\nauthor Au >> Thor <au.thor@xxxxxxxxxxx> 123456789 +0000\ncommitter Au Thor >> <au.thor@xxxxxxxxxxx> 123456789 >> +0000\n\nBlah Blah"..., len=220) >> at sha1dc/sha1.c:1731 >> #3 0x0030168c in git_SHA1DCUpdate (ctx=0xffbf8260, vdata=0x398aa0, >> len=273) at sha1dc/sha1.c:1808 >> #4 0x002a6f7c in write_sha1_file_prepare (buf=0x398aa0, len=273, >> type=0x959c8 "commit", sha1=0xffbfd630 "", >> hdr=0xffbf8c28 "commit 273", hdrlen=0xffbf8c24) at sha1_file.c:3207 >> #5 0x002a71ac in hash_sha1_file (buf=0x398aa0, len=273, type=0x959c8 >> "commit", sha1=0xffbfd630 "") at sha1_file.c:3266 >> #6 0x002a25f8 in check_sha1_signature (sha1=0xffbfdbb8 >> "\375\067\356\337\002", map=0x398aa0, size=273, type=0x959c8 "commit") >> at sha1_file.c:1644 >> #7 0x0022816c in parse_object (sha1=0xffbfdbb8 >> "\375\067\356\337\002") at object.c:269 >> #8 0x0027c258 in get_reference (revs=0xffbfdc88, name=0xa87f0 "HEAD", >> sha1=0xffbfdbb8 "\375\067\356\337\002", flags=0) >> at revision.c:196 >> #9 0x00284714 in setup_revisions (argc=0, argv=0x0, revs=0xffbfdc88, >> opt=0xffbfdc74) at revision.c:2295 >> #10 0x002ee4d8 in wt_status_collect_changes_index (s=0x348ea8 >> <s.24114>) at wt-status.c:585 >> #11 0x002eeae8 in wt_status_collect (s=0x348ea8 <s.24114>) at >> wt-status.c:701 >> #12 0x000db4fc in cmd_status (argc=0, argv=0xffbfe6fc, prefix=0x0) at >> builtin/commit.c:1393 >> #13 0x000acc24 in run_builtin (p=0x340ccc <commands+1200>, argc=1, >> argv=0xffbfe6fc) at git.c:371 >> #14 0x000acf98 in handle_builtin (argc=1, argv=0xffbfe6fc) at git.c:572 >> #15 0x000ad1a4 in run_argv (argcp=0xffbfe66c, argv=0xffbfe670) at >> git.c:624 >> #16 0x000ad3fc in cmd_main (argc=1, argv=0xffbfe6fc) at git.c:701 >> #17 0x001747a0 in main (argc=5, argv=0xffbfe6ec) at common-main.c:43 >> >> 1. Relevant part of uname -a: "SunOS <hostname> 5.11 11.3 sun4v sparc >> sun4v". >>