git notes main page | gitolite main page | license

IMPORTANT NOTE: although this page has a "gitolite.com" URL, this is not about gitolite. That's just an artifact of "sitaramc.github.com" being translated to "gitolite.com" and so ALL my git related stuff gets carried over. Gitolite documentation has another /gitolite in the URL, so you can tell. My apologies for this confusion.

For now, this is just loosely formatted text, maybe like a series of case studies.

IMPORTANT NOTE: git fsck --full is needed to reliably find repo corruption

1 case 1: Kolkata Korruption – 2 missing tree objects

what finally worked:

# on some good repo
TYPE=$(git cat-file -t $BADOBJSHA)
git cat-file $TYPE $BADOBJSHA > file

# copy file to bad repo
git hash-object -t $TYPE -w --stdin < file

However, this may not always work; it is not certain that hash-object will replace a corrupted object (as opposed to creating a missing object). So try that, as well as this (generic object):

# on some good repo
echo $object | git pack-objects --revs pack
# will create two files named pack-*.{idx,pack}

confirm:

git verify-pack -v pack-*.idx | grep $object
# should also contain all sub objects

copy:

pack* to $bad_repo/[.git?]/objects/pack

repack:

repack -a -d

(you could also do “unpack-objects” I guess)