When Subversion gets to this part of rep_read_contents, rb->len is
16384. It thinks it is then done reading the entire file, and can
compare the checksum, but it's not done with the file yet.
rb->rep.expanded_size is correct at the error point, 57465.
rep_read_get_baton sets rb->len to rb->rep.expanded_size, so I don't
know why the value changed by the time rep_read_contents got its paws
on the baton. I saw that rb->len might be getting clobbered by
rep_read_content's call to build_rep_list, which has the following
line of code:
*expanded_size = first_rep->expanded_size;
expanded_size is &rep->len. I haven't had a chance to debug this area
yet, so it might be fine.
I verified with sqlite3 that the rep-cache.db has the correct size (57465):
$ sqlite3 /mnt/d/svnclone/db/rep-cache.db "select * from rep_cache
where hash='e6291ab119036eb783d0136afccdb3b445867364'"
e6291ab119036eb783d0136afccdb3b445867364|227170|153|193|57465
On Mon, Mar 5, 2018 at 6:56 PM, Myria <myriachan_at_gmail.com> wrote:
> GMail keeps doing reply instead of reply all. I'm having to manually
> add the users list back now.
>
> Below is the thread I sent.
>
>
> ---------- Forwarded message ----------
> From: Myria <myriachan_at_gmail.com>
> Date: Mon, Mar 5, 2018 at 6:37 PM
> Subject: Re: SHA-1 collision in repository?
> To: Philip Martin <philip_at_codematters.co.uk>
>
>
> I now know where the checksum error happens, but not why.
>
> svn: E200014: Checksum mismatch while reading representation:
> expected: bb52be764a04d511ebb06e1889910dcf
> actual: 80a10d37de91cadc604ba30e379651b3
>
> It's calculating the MD5 of only the first 16 KB of the input file and
> comparing against the MD5 of the entire file. The 16 KB number seems
> to be SVN__STREAM_CHUNK_SIZE.
>
> bb52be764a04d511ebb06e1889910dcf is the MD5 of the entire file.
> 80a10d37de91cadc604ba30e379651b3 is the MD5 of the first 16384 bytes.
>
>
> On Mon, Mar 5, 2018 at 5:23 PM, Myria <myriachan_at_gmail.com> wrote:
>> I managed to compile a subversion command line client with debugging
>> information and optimizations disabled, and can reproduce the problem
>> with GDB attached.
>>
>> Here is a backtrace at the time at which the error occurs. A few line
>> numbers in stream.c will be wrong by a few lines due to a few printf's
>> I added.
>>
>> #0 svn_checksum_mismatch_err (expected=0x7ffffffdcf00,
>> actual=0x7ffffa0700a0, scratch_pool=0x7ffffa070028,
>> fmt=0x7ffffc259ac0 "Checksum mismatch while reading
>> representation") at subversion/libsvn_subr/checksum.c:638
>> #1 0x00007ffffc2123de in rep_read_contents (baton=0x7ffffa1f6190,
>> buf=0x7ffffa1f66a8 "// <redacted>"..., len=0x7ffffffdcf88)
>> at subversion/libsvn_fs_fs/cached_data.c:2062
>> #2 0x00007ffffe5645fd in svn_stream_read_full (stream=0x7ffffa1f6470,
>> buffer=0x7ffffa1f66a8 "// <redacted>"..., len=0x7ffffffdcf88)
>> at subversion/libsvn_subr/stream.c:193
>> #3 0x00007ffffe5653f3 in svn_stream_contents_same2
>> (same=0x7ffffffdd01c, stream1=0x7ffffa1f6470,
>> stream2=0x7ffffa1f6650, pool=0x7ffffa1e0028) at
>> subversion/libsvn_subr/stream.c:589
>> #4 0x00007ffffc247226 in get_shared_rep (old_rep=0x7ffffffdd188,
>> fs=0x7fffff601030, rep=0x7ffffa0e20b8,
>> file=0x7ffffa1e0390, offset=0, reps_hash=0x0,
>> result_pool=0x7fffff5e0028, scratch_pool=0x7ffffa1e0028)
>> at subversion/libsvn_fs_fs/transaction.c:2280
>> #5 0x00007ffffc247734 in rep_write_contents_close
>> (baton=0x7ffffa232ff0) at subversion/libsvn_fs_fs/transaction.c:2370
>> #6 0x00007ffffe56492b in svn_stream_close (stream=0x7ffffa233140) at
>> subversion/libsvn_subr/stream.c:274
>> #7 0x00007ffffe841001 in apply_window (window=0x0,
>> baton=0x7ffffa1000a0) at subversion/libsvn_delta/text_delta.c:732
>> #8 0x00007ffffc2520d2 in window_consumer (window=0x0,
>> baton=0x7fffff5f1ab8) at subversion/libsvn_fs_fs/tree.c:2935
>> #9 0x00007ffffe8405ef in svn_txdelta_run (source=0x7fffff5f1a18,
>> target=0x7fffff5f1298,
>> handler=0x7ffffc25209f <window_consumer>,
>> handler_baton=0x7fffff5f1ab8, checksum_kind=svn_checksum_md5,
>> checksum=0x7ffffffdd458, cancel_func=0x0, cancel_baton=0x0,
>> result_pool=0x7fffff5e0028,
>> scratch_pool=0x7fffff5e0028) at subversion/libsvn_delta/text_delta.c:454
>> #10 0x00007ffffee98a57 in svn_wc__internal_transmit_text_deltas (tempfile=0x0,
>> new_text_base_md5_checksum=0x7ffffffdd5b0,
>> new_text_base_sha1_checksum=0x7ffffffdd5b8, db=0x7fffff6c17d8,
>> local_abspath=0x7fffff672d08
>> "/mnt/d/svntest/repository/directory/Redacted.cpp",
>> fulltext=0, editor=0x7fffff673700, file_baton=0x7fffff510110,
>> result_pool=0x7fffff6c0028,
>> scratch_pool=0x7fffff5e0028) at subversion/libsvn_wc/adm_crawler.c:1109
>> #11 0x00007ffffee98d68 in svn_wc_transmit_text_deltas3
>> (new_text_base_md5_checksum=0x7ffffffdd5b0,
>> new_text_base_sha1_checksum=0x7ffffffdd5b8, wc_ctx=0x7fffff6c17c0,
>> local_abspath=0x7fffff672d08
>> "/mnt/d/svntest/repository/directory/Redacted.cpp",
>> fulltext=0, editor=0x7fffff673700, file_baton=0x7fffff510110,
>> result_pool=0x7fffff6c0028,
>> scratch_pool=0x7fffff5e0028) at subversion/libsvn_wc/adm_crawler.c:1199
>> #12 0x00007fffff18eb12 in svn_client__do_commit (
>> base_url=0x7fffff6142c0 "file:///mnt/d/svntest/repository/directory",
>> commit_items=0x7fffff672c48, editor=0x7fffff673700,
>> edit_baton=0x7fffff6300a0,
>> notify_path_prefix=0x7fffff672900 "/mnt/d/svntest/repository",
>> sha1_checksums=0x7ffffffdd750,
>> ctx=0x7fffff6c16f0, result_pool=0x7fffff6c0028, scratch_pool=0x7fffff650028)
>> at subversion/libsvn_client/commit_util.c:1920
>> #13 0x00007fffff18a5f9 in svn_client_commit6 (targets=0x7fffff670a18,
>> depth=svn_depth_infinity, keep_locks=0,
>> keep_changelists=0, commit_as_operations=1,
>> include_file_externals=0, include_dir_externals=0,
>> changelists=0x7fffff6c0780, revprop_table=0x0,
>> commit_callback=0x42c6a0 <svn_cl__print_commit_info>,
>> commit_baton=0x0, ctx=0x7fffff6c16f0, pool=0x7fffff6c0028) at
>> subversion/libsvn_client/commit.c:901
>> #14 0x000000000040b744 in svn_cl__commit (os=0x7fffff6c0520,
>> baton=0x7ffffffddc60, pool=0x7fffff6c0028)
>> at subversion/svn/commit-cmd.c:171
>> #15 0x000000000042b351 in sub_main (exit_code=0x7ffffffddf3c, argc=5,
>> argv=0x7ffffffde038, pool=0x7fffff6c0028)
>> at subversion/svn/svn.c:3041
>> #16 0x000000000042b5ee in main (argc=5, argv=0x7ffffffde038) at
>> subversion/svn/svn.c:3126
>>
Received on 2018-03-06 04:41:53 CET