Commit graph

63 commits

Author SHA1 Message Date
Junio C Hamano
b2f44feba5 Merge branch 'js/fsck-opt'
Allow ignoring fsck errors on specific set of known-to-be-bad
objects, and also tweaking warning level of various kinds of non
critical breakages reported.

* js/fsck-opt:
  fsck: support ignoring objects in `git fsck` via fsck.skiplist
  fsck: git receive-pack: support excluding objects from fsck'ing
  fsck: introduce `git fsck --connectivity-only`
  fsck: support demoting errors to warnings
  fsck: document the new receive.fsck.<msg-id> options
  fsck: allow upgrading fsck warnings to errors
  fsck: optionally ignore specific fsck issues completely
  fsck: disallow demoting grave fsck errors to warnings
  fsck: add a simple test for receive.fsck.<msg-id>
  fsck: make fsck_tag() warn-friendly
  fsck: handle multiple authors in commits specially
  fsck: make fsck_commit() warn-friendly
  fsck: make fsck_ident() warn-friendly
  fsck: report the ID of the error/warning
  fsck (receive-pack): allow demoting errors to warnings
  fsck: offer a function to demote fsck errors to warnings
  fsck: provide a function to parse fsck message IDs
  fsck: introduce identifiers for fsck messages
  fsck: introduce fsck options
2015-08-03 11:01:18 -07:00
Junio C Hamano
acf7189512 Merge branch 'jc/fsck-retire-require-eoh'
A fix to a minor regression to "git fsck" in v2.2 era that started
complaining about a body-less tag object when it lacks a separator
empty line after its header to separate it with a non-existent body.

* jc/fsck-retire-require-eoh:
  fsck: it is OK for a tag and a commit to lack the body
2015-07-13 14:00:24 -07:00
Junio C Hamano
84d18c0bcf fsck: it is OK for a tag and a commit to lack the body
When fsck validates a commit or a tag, it scans each line in the
header of the object using helper functions such as "start_with()",
etc. that work on a NUL terminated buffer, but before a1e920a0
(index-pack: terminate object buffers with NUL, 2014-12-08), the
validation functions were fed the object data in a piece of memory
that is not necessarily terminated with a NUL.

We added a helper function require_end_of_header() to be called at
the beginning of these validation functions to insist that the
object data contains an empty line before its end.  The theory is
that the validating functions will notice and stop when it hits an
empty line as a normal end of header (or a required header line that
is missing) without scanning past the end of potentially not
NUL-terminated buffer.

But the theory forgot that in the older days, Git itself happily
created objects with only the header lines without a body. This
caused Git 2.2 and later to issue an unnecessary warning in some
existing repositories.

With a1e920a0, we do not need to require an empty line (or the body)
in these objects to safely parse and validate them.  Drop the
offending "must have an empty line" check from this helper function,
while keeping the other check to make sure that there is no NUL in
the header part of the object, and adjust the name of the helper to
what it does accordingly.

Noticed-by: Wolfgang Denk <wd@denx.de>
Helped-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2015-06-28 14:47:28 -07:00
Johannes Schindelin
cd94c6f91e fsck: git receive-pack: support excluding objects from fsck'ing
The optional new config option `receive.fsck.skipList` specifies the path
to a file listing the names, i.e. SHA-1s, one per line, of objects that
are to be ignored by `git receive-pack` when `receive.fsckObjects = true`.

This is extremely handy in case of legacy repositories where it would
cause more pain to change incorrect objects than to live with them
(e.g. a duplicate 'author' line in an early commit object).

The intended use case is for server administrators to inspect objects
that are reported by `git push` as being too problematic to enter the
repository, and to add the objects' SHA-1 to a (preferably sorted) file
when the objects are legitimate, i.e. when it is determined that those
problematic objects should be allowed to enter the server.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2015-06-23 14:27:37 -07:00
Johannes Schindelin
f27d05b170 fsck: allow upgrading fsck warnings to errors
The 'invalid tag name' and 'missing tagger entry' warnings can now be
upgraded to errors by specifying `invalidTagName` and
`missingTaggerEntry` in the receive.fsck.<msg-id> config setting.

Incidentally, the missing tagger warning is now really shown as a warning
(as opposed to being reported with the "error:" prefix, as it used to be
the case before this commit).

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2015-06-23 14:27:36 -07:00
Johannes Schindelin
efaba7cc77 fsck: optionally ignore specific fsck issues completely
An fsck issue in a legacy repository might be so common that one would
like not to bother the user with mentioning it at all. With this change,
that is possible by setting the respective message type to "ignore".

This change "abuses" the missingEmail=warn test to verify that "ignore"
is also accepted and works correctly. And while at it, it makes sure
that multiple options work, too (they are passed to unpack-objects or
index-pack as a comma-separated list via the --strict=... command-line
option).

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2015-06-23 14:27:36 -07:00
Johannes Schindelin
f50c440730 fsck: disallow demoting grave fsck errors to warnings
Some kinds of errors are intrinsically unrecoverable (e.g. errors while
uncompressing objects). It does not make sense to allow demoting them to
mere warnings.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2015-06-23 14:27:36 -07:00
Johannes Schindelin
7d7d5b0568 fsck: make fsck_tag() warn-friendly
When fsck_tag() identifies a problem with the commit, it should try
to make it possible to continue checking the commit object, in case the
user wants to demote the detected errors to mere warnings.

Just like fsck_commit(), there are certain problems that could hide other
issues with the same tag object. For example, if the 'type' line is not
encountered in the correct position, the 'tag' line – if there is any –
would not be handled at all.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2015-06-23 14:27:35 -07:00
Johannes Schindelin
c9ad147f83 fsck: handle multiple authors in commits specially
This problem has been detected in the wild, and is the primary reason
to introduce an option to demote certain fsck errors to warnings. Let's
offer to ignore this particular problem specifically.

Technically, we could handle such repositories by setting
receive.fsck.<msg-id> to missingCommitter=warn, but that could hide
missing tree objects in the same commit because we cannot continue
verifying any commit object after encountering a missing committer line,
while we can continue in the case of multiple author lines.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2015-06-23 14:27:35 -07:00
Johannes Schindelin
b3584761eb fsck: make fsck_commit() warn-friendly
When fsck_commit() identifies a problem with the commit, it should try
to make it possible to continue checking the commit object, in case the
user wants to demote the detected errors to mere warnings.

Note that some problems are too problematic to simply ignore. For
example, when the header lines are mixed up, we punt after encountering
an incorrect line. Therefore, demoting certain warnings to errors can
hide other problems. Example: demoting the missingauthor error to
a warning would hide a problematic committer line.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2015-06-23 14:27:35 -07:00
Johannes Schindelin
e6826e335a fsck: make fsck_ident() warn-friendly
When fsck_ident() identifies a problem with the ident, it should still
advance the pointer to the next line so that fsck can continue in the
case of a mere warning.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2015-06-23 14:27:35 -07:00
Johannes Schindelin
71ab8fa840 fsck: report the ID of the error/warning
Some repositories written by legacy code have objects with non-fatal
fsck issues. To allow the user to ignore those issues, let's print
out the ID (e.g. when encountering "missingEmail", the user might
want to call `git config --add receive.fsck.missingEmail=warn`).

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2015-06-23 14:27:35 -07:00
Johannes Schindelin
5d477a334a fsck (receive-pack): allow demoting errors to warnings
For example, missing emails in commit and tag objects can be demoted to
mere warnings with

	git config receive.fsck.missingemail=warn

The value is actually a comma-separated list.

In case that the same key is listed in multiple receive.fsck.<msg-id>
lines in the config, the latter configuration wins (this can happen for
example when both $HOME/.gitconfig and .git/config contain message type
settings).

As git receive-pack does not actually perform the checks, it hands off
the setting to index-pack or unpack-objects in the form of an optional
argument to the --strict option.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2015-06-23 14:27:34 -07:00
Johannes Schindelin
0282f4dced fsck: offer a function to demote fsck errors to warnings
There are legacy repositories out there whose older commits and tags
have issues that prevent pushing them when 'receive.fsckObjects' is set.
One real-life example is a commit object that has been hand-crafted to
list two authors.

Often, it is not possible to fix those issues without disrupting the
work with said repositories, yet it is still desirable to perform checks
by setting `receive.fsckObjects = true`. This commit is the first step
to allow demoting specific fsck issues to mere warnings.

The `fsck_set_msg_types()` function added by this commit parses a list
of settings in the form:

	missingemail=warn,badname=warn,...

Unfortunately, the FSCK_WARN/FSCK_ERROR flag is only really heeded by
git fsck so far, but other call paths (e.g. git index-pack --strict)
error out *always* no matter what type was specified. Therefore, we need
to take extra care to set all message types to FSCK_ERROR by default in
those cases.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2015-06-23 14:26:46 -07:00
Johannes Schindelin
f417eed8cd fsck: provide a function to parse fsck message IDs
These functions will be used in the next commits to allow the user to
ask fsck to handle specific problems differently, e.g. demoting certain
errors to warnings. The upcoming `fsck_set_msg_types()` function has to
handle partial strings because we would like to be able to parse, say,
'missingemail=warn,missingtaggerentry=warn' command line parameters
(which will be passed by receive-pack to index-pack and unpack-objects).

To make the parsing robust, we generate strings from the enum keys, and
using these keys, we match up strings without dashes case-insensitively
to the corresponding enum values.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2015-06-22 12:53:25 -07:00
Johannes Schindelin
c99ba492f1 fsck: introduce identifiers for fsck messages
Instead of specifying whether a message by the fsck machinery constitutes
an error or a warning, let's specify an identifier relating to the
concrete problem that was encountered. This is necessary for upcoming
support to be able to demote certain errors to warnings.

In the process, simplify the requirements on the calling code: instead of
having to handle full-blown varargs in every callback, we now send a
string buffer ready to be used by the callback.

We could use a simple enum for the message IDs here, but we want to
guarantee that the enum values are associated with the appropriate
message types (i.e. error or warning?). Besides, we want to introduce a
parser in the next commit that maps the string representation to the
enum value, hence we use the slightly ugly preprocessor construct that
is extensible for use with said parser.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2015-06-22 10:24:27 -07:00
Johannes Schindelin
22410549fc fsck: introduce fsck options
Just like the diff machinery, we are about to introduce more settings,
therefore it makes sense to carry them around as a (pointer to a) struct
containing all of them.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2015-06-22 10:23:32 -07:00
Junio C Hamano
1cb4b3d380 Merge branch 'js/fsck-tag-validation'
New tag object format validation added in 2.2 showed garbage
after a tagname it reported in its error message.

* js/fsck-tag-validation:
  index-pack: terminate object buffers with NUL
  fsck: properly bound "invalid tag name" error message
2014-12-22 12:27:41 -08:00
Junio C Hamano
77933f4449 Sync with v2.1.4
* maint-2.1:
  Git 2.1.4
  Git 2.0.5
  Git 1.9.5
  Git 1.8.5.6
  fsck: complain about NTFS ".git" aliases in trees
  read-cache: optionally disallow NTFS .git variants
  path: add is_ntfs_dotgit() helper
  fsck: complain about HFS+ ".git" aliases in trees
  read-cache: optionally disallow HFS+ .git variants
  utf8: add is_hfs_dotgit() helper
  fsck: notice .git case-insensitively
  t1450: refactor ".", "..", and ".git" fsck tests
  verify_dotfile(): reject .git case-insensitively
  read-tree: add tests for confusing paths like ".." and ".git"
  unpack-trees: propagate errors adding entries to the index
2014-12-17 11:46:57 -08:00
Junio C Hamano
58f1d950e3 Sync with v2.0.5
* maint-2.0:
  Git 2.0.5
  Git 1.9.5
  Git 1.8.5.6
  fsck: complain about NTFS ".git" aliases in trees
  read-cache: optionally disallow NTFS .git variants
  path: add is_ntfs_dotgit() helper
  fsck: complain about HFS+ ".git" aliases in trees
  read-cache: optionally disallow HFS+ .git variants
  utf8: add is_hfs_dotgit() helper
  fsck: notice .git case-insensitively
  t1450: refactor ".", "..", and ".git" fsck tests
  verify_dotfile(): reject .git case-insensitively
  read-tree: add tests for confusing paths like ".." and ".git"
  unpack-trees: propagate errors adding entries to the index
2014-12-17 11:42:28 -08:00
Junio C Hamano
5e519fb8b0 Sync with v1.9.5
* maint-1.9:
  Git 1.9.5
  Git 1.8.5.6
  fsck: complain about NTFS ".git" aliases in trees
  read-cache: optionally disallow NTFS .git variants
  path: add is_ntfs_dotgit() helper
  fsck: complain about HFS+ ".git" aliases in trees
  read-cache: optionally disallow HFS+ .git variants
  utf8: add is_hfs_dotgit() helper
  fsck: notice .git case-insensitively
  t1450: refactor ".", "..", and ".git" fsck tests
  verify_dotfile(): reject .git case-insensitively
  read-tree: add tests for confusing paths like ".." and ".git"
  unpack-trees: propagate errors adding entries to the index
2014-12-17 11:28:54 -08:00
Junio C Hamano
6898b79721 Sync with v1.8.5.6
* maint-1.8.5:
  Git 1.8.5.6
  fsck: complain about NTFS ".git" aliases in trees
  read-cache: optionally disallow NTFS .git variants
  path: add is_ntfs_dotgit() helper
  fsck: complain about HFS+ ".git" aliases in trees
  read-cache: optionally disallow HFS+ .git variants
  utf8: add is_hfs_dotgit() helper
  fsck: notice .git case-insensitively
  t1450: refactor ".", "..", and ".git" fsck tests
  verify_dotfile(): reject .git case-insensitively
  read-tree: add tests for confusing paths like ".." and ".git"
  unpack-trees: propagate errors adding entries to the index
2014-12-17 11:20:31 -08:00
Johannes Schindelin
d08c13b947 fsck: complain about NTFS ".git" aliases in trees
Now that the index can block pathnames that can be mistaken
to mean ".git" on NTFS and FAT32, it would be helpful for
fsck to notice such problematic paths. This lets servers
which use receive.fsckObjects block them before the damage
spreads.

Note that the fsck check is always on, even for systems
without core.protectNTFS set. This is technically more
restrictive than we need to be, as a set of users on ext4
could happily use these odd filenames without caring about
NTFS.

However, on balance, it's helpful for all servers to block
these (because the paths can be used for mischief, and
servers which bother to fsck would want to stop the spread
whether they are on NTFS themselves or not), and hardly
anybody will be affected (because the blocked names are
variants of .git or git~1, meaning mischief is almost
certainly what the tree author had in mind).

Ideally these would be controlled by a separate
"fsck.protectNTFS" flag. However, it would be much nicer to
be able to enable/disable _any_ fsck flag individually, and
any scheme we choose should match such a system. Given the
likelihood of anybody using such a path in practice, it is
not unreasonable to wait until such a system materializes.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-12-17 11:04:45 -08:00
Jeff King
a18fcc9ff2 fsck: complain about HFS+ ".git" aliases in trees
Now that the index can block pathnames that case-fold to
".git" on HFS+, it would be helpful for fsck to notice such
problematic paths. This lets servers which use
receive.fsckObjects block them before the damage spreads.

Note that the fsck check is always on, even for systems
without core.protectHFS set. This is technically more
restrictive than we need to be, as a set of users on ext4
could happily use these odd filenames without caring about
HFS+.

However, on balance, it's helpful for all servers to block
these (because the paths can be used for mischief, and
servers which bother to fsck would want to stop the spread
whether they are on HFS+ themselves or not), and hardly
anybody will be affected (because the blocked names are
variants of .git with invisible Unicode code-points mixed
in, meaning mischief is almost certainly what the tree
author had in mind).

Ideally these would be controlled by a separate
"fsck.protectHFS" flag. However, it would be much nicer to
be able to enable/disable _any_ fsck flag individually, and
any scheme we choose should match such a system. Given the
likelihood of anybody using such a path in practice, it is
not unreasonable to wait until such a system materializes.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-12-17 11:04:45 -08:00
Jeff King
76e86fc6e3 fsck: notice .git case-insensitively
We complain about ".git" in a tree because it cannot be
loaded into the index or checked out. Since we now also
reject ".GIT" case-insensitively, fsck should notice the
same, so that errors do not propagate.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-12-17 11:04:39 -08:00
Jeff King
7add441984 fsck: properly bound "invalid tag name" error message
When we detect an invalid tag-name header in a tag object,
like, "tag foo bar\n", we feed the pointer starting at "foo
bar" to a printf "%s" formatter. This shows the name, as we
want, but then it keeps printing the rest of the tag buffer,
rather than stopping at the end of the line.

Our tests did not notice because they look only for the
matching line, but the bug is that we print much more than
we wanted to. So we also adjust the test to be more exact.

Note that when fscking tags with "index-pack --strict", this
is even worse. index-pack does not add a trailing
NUL-terminator after the object, so we may actually read
past the buffer and print uninitialized memory. Running
t5302 with valgrind does notice the bug for that reason.

Signed-off-by: Jeff King <peff@peff.net>
Acked-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-12-09 11:54:25 -08:00
Johannes Schindelin
cec097be3a fsck: check tag objects' headers
We inspect commit objects pretty much in detail in git-fsck, but we just
glanced over the tag objects. Let's be stricter.

Since we do not want to limit 'tag' lines unduly, values that would fail
the refname check only result in warnings, not errors.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-09-11 10:44:26 -07:00
Johannes Schindelin
4d0d89755e Make sure fsck_commit_buffer() does not run out of the buffer
So far, we assumed that the buffer is NUL terminated, but this is not
a safe assumption, now that we opened the fsck_object() API to pass a
buffer directly.

So let's make sure that there is at least an empty line in the buffer.
That way, our checks would fail if the empty line was encountered
prematurely, and consequently we can get away with the current string
comparisons even with non-NUL-terminated buffers are passed to
fsck_object().

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-09-11 10:44:01 -07:00
Johannes Schindelin
90a398bbd7 fsck_object(): allow passing object data separately from the object itself
When fsck'ing an incoming pack, we need to fsck objects that cannot be
read via read_sha1_file() because they are not local yet (and might even
be rejected if transfer.fsckobjects is set to 'true').

For commits, there is a hack in place: we basically cache commit
objects' buffers anyway, but the same is not true, say, for tag objects.

By refactoring fsck_object() to take the object buffer and size as
optional arguments -- optional, because we still fall back to the
previous method to look at the cached commit objects if the caller
passes NULL -- we prepare the machinery for the upcoming handling of tag
objects.

The assumption that such buffers are inherently NUL terminated is now
wrong, of course, hence we pass the size of the buffer so that we can
add a sanity check later, to prevent running past the end of the buffer.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-09-10 13:54:21 -07:00
René Scharfe
9d02150cf4 fsck: simplify fsck_commit_buffer() by using commit_list_count()
fsck_commit_buffer() checks that the number of items in the parents
list of a commit matches the number of parent lines in its buffer or --
if a graft is used -- the number of parents in that graft.  Simplify
the code by using commit_list_count() instead of counting by hand.
Also use different variables for the number of lines and the number of
list items, making it easier to compare them.

Signed-off-by: Rene Scharfe <l.s.r@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-07-10 14:10:27 -07:00
Junio C Hamano
e91ae32a01 Merge branch 'jk/skip-prefix'
* jk/skip-prefix:
  http-push: refactor parsing of remote object names
  imap-send: use skip_prefix instead of using magic numbers
  use skip_prefix to avoid repeated calculations
  git: avoid magic number with skip_prefix
  fetch-pack: refactor parsing in get_ack
  fast-import: refactor parsing of spaces
  stat_opt: check extra strlen call
  daemon: use skip_prefix to avoid magic numbers
  fast-import: use skip_prefix for parsing input
  use skip_prefix to avoid repeating strings
  use skip_prefix to avoid magic numbers
  transport-helper: avoid reading past end-of-string
  fast-import: fix read of uninitialized argv memory
  apply: use skip_prefix instead of raw addition
  refactor skip_prefix to return a boolean
  avoid using skip_prefix as a boolean
  daemon: mark some strings as const
  parse_diff_color_slot: drop ofs parameter
2014-07-09 11:33:28 -07:00
Jeff King
cf4fff579e refactor skip_prefix to return a boolean
The skip_prefix() function returns a pointer to the content
past the prefix, or NULL if the prefix was not found. While
this is nice and simple, in practice it makes it hard to use
for two reasons:

  1. When you want to conditionally skip or keep the string
     as-is, you have to introduce a temporary variable.
     For example:

       tmp = skip_prefix(buf, "foo");
       if (tmp)
	       buf = tmp;

  2. It is verbose to check the outcome in a conditional, as
     you need extra parentheses to silence compiler
     warnings. For example:

       if ((cp = skip_prefix(buf, "foo"))
	       /* do something with cp */

Both of these make it harder to use for long if-chains, and
we tend to use starts_with() instead. However, the first line
of "do something" is often to then skip forward in buf past
the prefix, either using a magic constant or with an extra
strlen(3) (which is generally computed at compile time, but
means we are repeating ourselves).

This patch refactors skip_prefix() to return a simple boolean,
and to provide the pointer value as an out-parameter. If the
prefix is not found, the out-parameter is untouched. This
lets you write:

  if (skip_prefix(arg, "foo ", &arg))
	  do_foo(arg);
  else if (skip_prefix(arg, "bar ", &arg))
	  do_bar(arg);

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-06-20 10:44:43 -07:00
Jeff King
8597ea3afe commit: record buffer length in cache
Most callsites which use the commit buffer try to use the
cached version attached to the commit, rather than
re-reading from disk. Unfortunately, that interface provides
only a pointer to the NUL-terminated buffer, with no
indication of the original length.

For the most part, this doesn't matter. People do not put
NULs in their commit messages, and the log code is happy to
treat it all as a NUL-terminated string. However, some code
paths do care. For example, when checking signatures, we
want to be very careful that we verify all the bytes to
avoid malicious trickery.

This patch just adds an optional "size" out-pointer to
get_commit_buffer and friends. The existing callers all pass
NULL (there did not seem to be any obvious sites where we
could avoid an immediate strlen() call, though perhaps with
some further refactoring we could).

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-06-13 12:09:38 -07:00
Jeff King
bc6b8fc130 use get_commit_buffer everywhere
Each of these sites assumes that commit->buffer is valid.
Since they would segfault if this was not the case, they are
likely to be correct in practice. However, we can
future-proof them by using get_commit_buffer.

And as a side effect, we abstract away the final bare uses
of commit->buffer.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-06-13 12:08:17 -07:00
Junio C Hamano
f7804e250d Merge branch 'hs/simplify-bit-setting-in-fsck-tree'
* hs/simplify-bit-setting-in-fsck-tree:
  fsck: use bitwise-or assignment operator to set flag
2014-03-31 16:30:44 -07:00
Junio C Hamano
40adf520a3 Merge branch 'ys/fsck-commit-parsing'
* ys/fsck-commit-parsing:
  fsck.c:fsck_commit(): use skip_prefix() to verify and skip constant
  fsck.c:fsck_ident(): ident points at a const string
2014-03-28 13:51:24 -07:00
Hiroyuki Sano
effd12ec87 fsck: use bitwise-or assignment operator to set flag
fsck_tree() has two different ways to set a flag variable, either by
using a if-statement that guards an assignment, or by using a
bitwise-or assignment operator.  Most are done with the former, and
only one variable is assigned with the latter.

Since all the conditions are short-and-sweet, we can afford to
uniformly use the latter style, which makes the resulting code
shorter and easier to read.

Signed-off-by: Hiroyuki Sano <sh19910711@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-03-20 11:20:48 -07:00
Yuxuan Shui
2d820a61df fsck.c:fsck_commit(): use skip_prefix() to verify and skip constant
fsck_commit() uses memcmp() to check if the buffer starts with a
certain prefix, and skips the prefix if it does.

This is exactly what skip_prefix() was designed for.

Signed-off-by: Yuxuan Shui <yshuiv7@gmail.com>
Helped-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-03-19 15:34:56 -07:00
Yuxuan Shui
de42180f6a fsck.c:fsck_ident(): ident points at a const string
Since fsck_ident doesn't change the content of **ident, the type of
ident could be const char **.

This change is required to rewrite fsck_commit() to use skip_prefix().

Signed-off-by: Yuxuan Shui <yshuiv7@gmail.com>
Helped-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-03-13 13:00:30 -07:00
Jeff King
7ca36d9398 date: check date overflow against time_t
When we check whether a timestamp has overflowed, we check
only against ULONG_MAX, meaning that strtoul has overflowed.
However, we also feed these timestamps to system functions
like gmtime, which expect a time_t. On many systems, time_t
is actually smaller than "unsigned long" (e.g., because it
is signed), and we would overflow when using these
functions.  We don't know the actual size or signedness of
time_t, but we can easily check for truncation with a simple
assignment.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-02-24 10:12:58 -08:00
Jeff King
d4b8de0420 fsck: report integer overflow in author timestamps
When we check commit objects, we complain if commit->date is
ULONG_MAX, which is an indication that we saw integer
overflow when parsing it. However, we do not do any check at
all for author lines, which also contain a timestamp.

Let's actually check the timestamps on each ident line
with strtoul. This catches both author and committer lines,
and we can get rid of the now-redundant commit->date check.

Note that like the existing check, we compare only against
ULONG_MAX. Now that we are calling strtoul at the site of
the check, we could be slightly more careful and also check
that errno is set to ERANGE. However, this will make further
refactoring in future patches a little harder, and it
doesn't really matter in practice.

For 32-bit systems, one would have to create a commit at the
exact wrong second in 2038. But by the time we get close to
that, all systems will hopefully have moved to 64-bit (and
if they haven't, they have a real problem one second later).

For 64-bit systems, by the time we get close to ULONG_MAX,
all systems will hopefully have been consumed in the fiery
wrath of our expanding Sun.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-02-24 10:12:58 -08:00
Jeff King
5c17f51270 fsck: warn about ".git" in trees
Having a ".git" entry inside a tree can cause confusing
results on checkout. At the top-level, you could not
checkout such a tree, as it would complain about overwriting
the real ".git" directory. In a subdirectory, you might
check it out, but performing operations in the subdirectory
would confusingly consider the in-tree ".git" directory as
the repository.

The regular git tools already make it hard to accidentally
add such an entry to a tree, and do not allow such entries
to enter the index at all. Teaching fsck about it provides
an additional safety check, and let's us avoid propagating
any such bogosity when transfer.fsckObjects is on.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2012-11-28 13:52:54 -08:00
Jeff King
5d34a4359d fsck: warn about '.' and '..' in trees
A tree with meta-paths like '.' or '..' does not work well
with git; the index will refuse to load it or check it out
to the filesystem (and even if we did not have that safety,
it would look like we were overwriting an untracked
directory). For the same reason, it is difficult to create
such a tree with regular git.

Let's warn about these dubious entries during fsck, just in
case somebody has created a bogus tree (and this also lets
us prevent them from propagating when transfer.fsckObjects
is set).

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2012-11-28 10:41:08 -08:00
Junio C Hamano
03adeeaad6 Merge branch 'jk/maint-null-in-trees' into maint-1.7.11
"git diff" had a confusion between taking data from a path in the
working tree and taking data from an object that happens to have
name 0{40} recorded in a tree.

* jk/maint-null-in-trees:
  fsck: detect null sha1 in tree entries
  do not write null sha1s to on-disk index
  diff: do not use null sha1 as a sentinel value
2012-09-10 15:24:54 -07:00
Jeff King
c479d14a80 fsck: detect null sha1 in tree entries
Short of somebody happening to beat the 1 in 2^160 odds of
actually generating content that hashes to the null sha1, we
should never see this value in a tree entry. So let's have
fsck warn if it it seen.

As in the previous commit, we test both blob and submodule
entries to future-proof the test suite against the
implementation depending on connectivity to notice the
error.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2012-07-29 15:14:08 -07:00
Pete Wyckoff
82247e9bd5 remove superfluous newlines in error messages
The error handling routines add a newline.  Remove
the duplicate ones in error messages.

Signed-off-by: Pete Wyckoff <pw@padd.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2012-04-30 15:45:51 -07:00
Dmitry Ivankov
53f53cff24 fsck: improve committer/author check
fsck allows a name with > character in it like "name> <email>". Also for
"name email>" fsck says "missing space before email".

More precisely, it seeks for a first '<', checks that ' ' preceeds it.
Then seeks to '<' or '>' and checks that it is the '>'. Missing space is
reported if either '<' is not found or it's not preceeded with ' '.

Change it to following. Seek to '<' or '>', check that it is '<' and is
preceeded with ' '. Seek to '<' or '>' and check that it is '>'. So now
"name> <email>" is rejected as "bad name". More strict name check is the
only change in what is accepted.

Report 'missing space' only if '<' is found and is not preceeded with a
space.

Signed-off-by: Dmitry Ivankov <divanorama@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2011-08-11 12:21:07 -07:00
Junio C Hamano
5b42477b59 Merge branch 'jm/maint-misc-fix' into maint
* jm/maint-misc-fix:
  read_gitfile_gently: use ssize_t to hold read result
  remove tests of always-false condition
  rerere.c: diagnose a corrupt MERGE_RR when hitting EOF between TAB and '\0'
2011-05-30 00:09:41 -07:00
Jim Meyering
5dd564895e remove tests of always-false condition
* fsck.c (fsck_error_function): Don't test obj->sha1 == 0.
It can never be true, since that sha1 member is an array.
* transport.c (set_upstreams): Likewise for ref->new_sha1.

Signed-off-by: Jim Meyering <meyering@redhat.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2011-05-26 11:24:24 -07:00
Jeff King
ebeb60900f strbuf: add strbuf_vaddf
In a variable-args function, the code for writing into a strbuf is
non-trivial. We ended up cutting and pasting it in several places
because there was no vprintf-style function for strbufs (which in turn
was held up by a lack of va_copy).

Now that we have a fallback va_copy, we can add strbuf_vaddf, the
strbuf equivalent of vsprintf. And we can clean up the cut and paste
mess.

Signed-off-by: Jeff King <peff@peff.net>
Improved-by: Christian Couder <christian.couder@gmail.com>
Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2011-02-26 01:06:50 -08:00