Ever since a64215b6cd ("object.h: stop depending on cache.h; make
cache.h depend on object.h", 2023-02-24), we have a few headers that
could have replaced their include of cache.h with an include of
object.h. Make that change now.
Some C files had to start including cache.h after this change (or some
smaller header it had brought in), because the C files were depending
on things from cache.h but were only formerly implicitly getting
cache.h through one of these headers being modified in this patch.
Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This allows us to replace includes of cache.h with includes of the much
smaller alloc.h in many places. It does mean that we also need to add
includes of alloc.h in a number of C files.
Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The fsck code operates on an object buffer represented as a pointer/len
combination. However, the parsing of commits and tags is a little bit
loose; we mostly scan left-to-right through the buffer, without checking
whether we've gone past the length we were given.
This has traditionally been OK because the buffers we feed to fsck
always have an extra NUL after the end of the object content, which ends
any left-to-right scan. That has always been true for objects we read
from the odb, and we made it true for incoming index-pack/unpack-objects
checks in a1e920a0a7 (index-pack: terminate object buffers with NUL,
2014-12-08).
However, we recently added an exception: hash-object asks index_fd() to
do fsck checks. That _may_ have an extra NUL (if we read from a pipe
into a strbuf), but it might not (if we read the contents from the
file). Nor can we just teach it to always add a NUL. We may mmap the
on-disk file, which will not have any extra bytes (if it's a multiple of
the page size). Not to mention that this is a rather subtle assumption
for the fsck code to make.
Instead, let's make sure that the fsck parsers don't ever look past the
size of the buffer they've been given. This _almost_ works already,
thanks to earlier work in 4d0d89755e (Make sure fsck_commit_buffer()
does not run out of the buffer, 2014-09-11). The theory there is that we
check up front whether we have the end of header double-newline
separator. And then any left-to-right scanning we do is OK as long as it
stops when it hits that boundary.
However, we later softened that in 84d18c0bcf (fsck: it is OK for a tag
and a commit to lack the body, 2015-06-28), which allows the
double-newline header to be missing, but does require that the header
ends in a newline. That was OK back then, because of the NUL-termination
guarantees (including the one from a1e920a0a7 mentioned above).
Because 84d18c0bcf guarantees that any header line does end in a
newline, we are still OK with most of the left-to-right scanning. We
only need to take care after completing a line, to check that there is
another line (and we didn't run out of buffer).
Most of these checks are just need to check "buffer < buffer_end" (where
buffer is advanced as we parse) before scanning for the next header
line. But here are a few notes:
- we don't technically need to check for remaining buffer before
parsing the very first line ("tree" for a commit, or "object" for a
tag), because verify_headers() rejects a totally empty buffer. But
we'll do so in the name of consistency and defensiveness.
- there are some calls to strchr('\n'). These are actually OK by the
"the final header line must end in a newline" guarantee from
verify_headers(). They will always find that rather than run off the
end of the buffer. Curiously, they do check for a NULL return and
complain, but I believe that condition can never be reached.
However, I converted them to use memchr() with a proper size and
retained the NULL checks. Using memchr() is not much longer and
makes it more obvious what is going on. Likewise, retaining the NULL
checks serves as a defensive measure in case my analysis is wrong.
- commit 9a1a3a4d4c (mktag: allow omitting the header/body \n
separator, 2021-01-05), does check for the end-of-buffer condition,
but does so with "!*buffer", relying explicitly on the NUL
termination. We can accomplish the same thing with a pointer
comparison. I also folded it into the follow-on conditional that
checks the contents of the buffer, for consistency with the other
checks.
- fsck_ident() uses parse_timestamp(), which is based on strtoumax().
That function will happily skip past leading whitespace, including
newlines, which makes it a risk. We can fix this by scanning to the
first digit ourselves, and then using parse_timestamp() to do the
actual numeric conversion.
Note that as a side effect this fixes the fact that we missed
zero-padded timestamps like "<email> 0123" (whereas we would
complain about "<email> 0123"). I doubt anybody cares, but I
mention it here for completeness.
- fsck_tree() does not need any modifications. It relies on
decode_tree_entry() to do the actual parsing, and that function
checks both that there are enough bytes in the buffer to represent
an entry, and that there is a NUL at the appropriate spot (one
hash-length from the end; this may not be the NUL for the entry we
are parsing, but we know that in the worst case, everything from our
current position to that NUL is a filename, so we won't run out of
bytes).
In addition to fixing the code itself, we'd like to make sure our rather
subtle assumptions are not violated in the future. So this patch does
two more things:
- add comments around verify_headers() documenting the link between
what it checks and the memory safety of the callers. I don't expect
this code to be modified frequently, but this may help somebody from
accidentally breaking things.
- add a thorough set of tests covering truncations at various key
spots (e.g., for a "tree $oid" line, in the middle of the word
"tree", right after it, after the space, in the middle of the $oid,
and right at the end of the line. Most of these are fine already (it
is only truncating right at the end of the line that is currently
broken). And some of them are not even possible with the current
code (we parse "tree " as a unit, so truncating before the space is
equivalent). But I aimed here to consider the code a black box and
look for any truncations that would be a problem for a left-to-right
parser.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The fsck code has been slowly moving away from requiring an object
struct in commits like 103fb6d43b (fsck: accept an oid instead of a
"struct tag" for fsck_tag(), 2019-10-18), c5b4269b57 (fsck: accept an
oid instead of a "struct commit" for fsck_commit(), 2019-10-18), etc.
However, the only external interface that fsck.c provides is
fsck_object(), which requires an object struct, then promptly discards
everything except its oid and type. Let's factor out the post-discard
part of that function as fsck_buffer(), leaving fsck_object() as a thin
wrapper around it. That will provide more flexibility for callers which
may not have a struct.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Recently, a vulnerability was reported that can lead to an out-of-bounds
write when reading an unreasonably large gitattributes file. The root
cause of this error are multiple integer overflows in different parts of
the code when there are either too many lines, when paths are too long,
when attribute names are too long, or when there are too many attributes
declared for a pattern.
As all of these are related to size, it seems reasonable to restrict the
size of the gitattributes file via git-fsck(1). This allows us to both
stop distributing known-vulnerable objects via common hosting platforms
that have fsck enabled, and users to protect themselves by enabling the
`fetch.fsckObjects` config.
There are basically two checks:
1. We verify that size of the gitattributes file is smaller than
100MB.
2. We verify that the maximum line length does not exceed 2048
bytes.
With the preceding commits, both of these conditions would cause us to
either ignore the complete gitattributes file or blob in the first case,
or the specific line in the second case. Now with these consistency
checks added, we also grow the ability to stop distributing such files
in the first place when `receive.fsckObjects` is enabled.
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Move the checks for gitattributes so that they can be extended more
readily.
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
In `fsck_finish()` we check all blobs for consistency that we have found
during the tree walk, but that haven't yet been checked. This is only
required for gitmodules right now, but will also be required for a new
check for gitattributes.
Pull out a function `fsck_blobs()` that allows the caller to check a set
of blobs for consistency.
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
In general, we don't need to validate blob contents as they are opaque
blobs about whose content Git doesn't need to care about. There are some
exceptions though when blobs are linked into trees so that they would be
interpreted by Git. We only have a single such check right now though,
which is the one for gitmodules that has been added in the context of
CVE-2018-11235.
Now we have found another vulnerability with gitattributes that can lead
to out-of-bounds writes and reads. So let's refactor `fsck_blob()` so
that it is more extensible and can check different types of blobs.
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
We use the normal tree_desc code to iterate over trees in fsck, meaning
we only see the canonicalized modes it returns. And hence we'd never see
anything unexpected, since it will coerce literally any garbage into one
of our normal and accepted modes.
We can use the new RAW_MODES flag to see the real modes, and then use
the existing code to actually analyze them. The existing code is written
as allow-known-good, so there's not much point in testing a variety of
breakages. The one tested here should be S_IFREG but with nonsense
permissions.
Do note that the error-reporting here isn't great. We don't mention the
specific bad mode, but just that the tree has one or more broken modes.
But when you go to look at it with "git ls-tree", we'll report the
canonicalized mode! This isn't ideal, but given that this should come up
rarely, and that any number of other tree corruptions might force you
into looking at the binary bytes via "cat-file", it's not the end of the
world. And it's something we can improve on top later if we choose.
Reported-by: Xavier Morel <xavier.morel@masklinn.net>
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When using init_tree_desc() and tree_entry() to iterate over a tree, we
always canonicalize the modes coming out of the tree. This is a good
thing to prevent bugs or oddities in normal code paths, but it's
counter-productive for tools like fsck that want to see the exact
contents.
We can address this by adding an option to avoid the extra
canonicalization. A few notes on the implementation:
- I've attached the new option to the tree_desc struct itself. The
actual code change is in decode_tree_entry(), which is in turn
called by the public update_tree_entry(), tree_entry(), and
init_tree_desc() functions, plus their "gently" counterparts.
By letting it ride along in the struct, we can avoid changing the
signature of those functions, which are called many times. Plus it's
conceptually simpler: you really want a particular iteration of a
tree to be "raw" or not, rather than individual calls.
- We still have to set the new option somewhere. The struct is
initialized by init_tree_desc(). I added the new flags field only to
the "gently" version. That avoids disturbing the much more numerous
non-gentle callers, and it makes sense that anybody being careful
about looking at raw modes would also be careful about bogus trees
(i.e., the caller will be something like fsck in the first place).
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Add a path_match_flags() function and have the two sets of
starts_with_dot_{,dot_}slash() functions added in
63e95beb08 (submodule: port resolve_relative_url from shell to C,
2016-04-15) and a2b26ffb1a (fsck: convert gitmodules url to URL
passed to curl, 2020-04-18) be thin wrappers for it.
As the latter of those notes the fsck version was copied from the
initial builtin/submodule--helper.c version.
Since the code added in a2b26ffb1a was doing really doing the same as
win32_is_dir_sep() added in 1cadad6f65 (git clone <url>
C:\cygwin\home\USER\repo' is working (again), 2018-12-15) let's move
the latter to git-compat-util.h is a is_xplatform_dir_sep(). We can
then call either it or the platform-specific is_dir_sep() from this
new function.
Let's likewise change code in various other places that was hardcoding
checks for "'/' || '\\'" with the new is_xplatform_dir_sep(). As can
be seen in those callers some of them still concern themselves with
':' (Mac OS classic?), but let's leave the question of whether that
should be consolidated for some other time.
As we expect to make wider use of the "native" case in the future,
define and use two starts_with_dot_{,dot_}slash_native() convenience
wrappers. This makes the diff in builtin/submodule--helper.c much
smaller.
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Derrick Stolee <derrickstolee@github.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
In the commits merged in via 204333b015 (Merge branch
'jk/open-dotgitx-with-nofollow', 2021-03-22), we stopped following
symbolic links for .gitattributes, .gitignore, and .mailmap files.
Let's teach fsck to warn that these symlinks are not going to do
anything. Note that this is just a warning, and won't block the objects
via transfer.fsckObjects, since there are reported to be cases of this
in the wild (and even once fixed, they will continue to exist in the
commit history of those projects, but are not particularly dangerous).
Note that we won't add these to the existing gitmodules block in the
fsck code. The logic for gitmodules is a bit more complicated, as we
also check the content of non-symlink instances we find. But for these
new files, there is no content check; we're just looking at the name and
mode of the tree entry (and we can avoid even the complicated name
checks in the common case that the mode doesn't indicate a symlink).
We can reuse the test helper function we defined for .gitmodules, though
(it needs some slight adjustments for the fsck error code, and because
we don't block these symlinks via verify_path()).
Note that I didn't explicitly test the transfer.fsckObjects case here
(nor does the existing .gitmodules test that it blocks a push). The
translation of fsck severities to outcomes is covered in general in
t5504.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Many calls to report() in fsck_tree() are kept on a single line and are
quite long. Most were pretty big to begin with, but have gotten even
longer over the years as we've added more parameters. Let's accept the
churn of wrapping them in order to conform to our usual line limits.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Commit b2f2039c2b (fsck: accept an oid instead of a "struct tree" for
fsck_tree(), 2019-10-18) introduced a new "oid" parameter to
fsck_tree(), and we pass it to the report() function when we find
problems. However, that is shadowed within the tree-walking loop by the
existing "oid" variable which we use to store the oid of each tree
entry. As a result, we may report the wrong oid for some problems we
detect within the loop (the entry oid, instead of the tree oid).
Our tests didn't catch this because they checked only that we found the
expected fsck problem, not that it was attached to the correct object.
Let's rename both variables in the function to avoid confusion. This
makes the diff a little noisy (e.g., all of the report() calls outside
the loop were already correct but need to be touched), but makes sure we
catch all cases and will avoid similar confusion in the future.
And we can update the test to be a bit more specific and catch this
problem.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Refactor the check added in 5476e1efde (fetch-pack: print and use
dangling .gitmodules, 2021-02-22) to make use of us now passing the
"msg_id" to the user defined "error_func". We can now compare against
the FSCK_MSG_GITMODULES_MISSING instead of parsing the generated
message.
Let's also replace register_found_gitmodules() with directly
manipulating the "gitmodules_found" member. A recent commit moved it
into "fsck_options" so we could do this here.
I'm sticking this callback in fsck.c. Perhaps in the future we'd like
to accumulate such callbacks into another file (maybe fsck-cb.c,
similar to parse-options-cb.c?), but while we've got just the one
let's just put it into fsck.c.
A better alternative in this case would be some library some more
obvious library shared by fetch-pack.c ad builtin/index-pack.c, but
there isn't such a thing.
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Move the gitmodules_{found,done} static variables added in
159e7b080b (fsck: detect gitmodules files, 2018-05-02) into the
fsck_options struct. It makes sense to keep all the context in the
same place.
This requires changing the recently added register_found_gitmodules()
function added in 5476e1efde (fetch-pack: print and use dangling
.gitmodules, 2021-02-22) to take fsck_options. That function will be
removed in a subsequent commit, but as it'll require the new
gitmodules_found attribute of "fsck_options" we need this intermediate
step first.
An earlier version of this patch removed the small amount of
duplication we now have between FSCK_OPTIONS_{DEFAULT,STRICT} with a
FSCK_OPTIONS_COMMON macro. I don't think such de-duplication is worth
it for this amount of copy/pasting.
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Change code I added in acf9de4c94 (mktag: use fsck instead of custom
verify_tag(), 2021-01-05) to make use of a new API function that takes
the fsck_msg_{id,type} types, instead of arbitrary strings that
we'll (hopefully) parse into those types.
At the time that the fsck_set_msg_type() API was introduced in
0282f4dced (fsck: offer a function to demote fsck errors to warnings,
2015-06-22) it was only intended to be used to parse user-supplied
data.
For things that are purely internal to the C code it makes sense to
have the compiler check these arguments, and to skip the sanity
checking of the data in fsck_set_msg_type() which is redundant to
checks we get from the compiler.
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Change the fsck_error callback to also pass along the
fsck_msg_id. Before this change the only way to get the message id was
to parse it back out of the "message".
Let's pass it down explicitly for the benefit of callers that might
want to use it, as discussed in [1].
Passing the msg_type is now redundant, as you can always get it back
from the msg_id, but I'm not changing that convention. It's really
common to need the msg_type, and the report() function itself (which
calls "fsck_error") needs to call fsck_msg_type() to discover
it. Let's not needlessly re-do that work in the user callback.
1. https://lore.kernel.org/git/87blcja2ha.fsf@evledraar.gmail.com/
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Move the FOREACH_FSCK_MSG_ID macro and the fsck_msg_id enum it helps
define from fsck.c to fsck.h. This is in preparation for having
non-static functions take the fsck_msg_id as an argument.
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Rename the FOREACH_MSG_ID macro to FOREACH_FSCK_MSG_ID in preparation
for moving it over to fsck.h. It's good convention to name macros
in *.h files in such a way as to clearly not clash with any other
names in other files.
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
In f417eed8cd (fsck: provide a function to parse fsck message IDs,
2015-06-22) the "STR" macro was introduced, but that short macro name
was not undefined after use as was done earlier in the same series for
the MSG_ID macro in c99ba492f1 (fsck: introduce identifiers for fsck
messages, 2015-06-22).
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
There's no reason to defer the calling of parse_msg_type() until after
we've checked if the "id < 0". This is not a hot codepath, and
parse_msg_type() itself may die on invalid input.
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Move the FSCK_{FATAL,INFO,ERROR,WARN,IGNORE} defines into a new
fsck_msg_type enum.
These defines were originally introduced in:
- ba002f3b28 (builtin-fsck: move common object checking code to
fsck.c, 2008-02-25)
- f50c440730 (fsck: disallow demoting grave fsck errors to warnings,
2015-06-22)
- efaba7cc77 (fsck: optionally ignore specific fsck issues
completely, 2015-06-22)
- f27d05b170 (fsck: allow upgrading fsck warnings to errors,
2015-06-22)
The reason these were defined in two different places is because we
use FSCK_{IGNORE,INFO,FATAL} only in fsck.c, but FSCK_{ERROR,WARN} are
used by external callbacks.
Untangling that would take some more work, since we expose the new
"enum fsck_msg_type" to both. Similar to "enum object_type" it's not
worth structuring the API in such a way that only those who need
FSCK_{ERROR,WARN} pass around a different type.
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Refactor "if options->msg_type" and other code added in
0282f4dced (fsck: offer a function to demote fsck errors to warnings,
2015-06-22) to reduce the scope of the "int msg_type" variable.
This is in preparation for changing its type in a subsequent commit,
only using it in the "!options->msg_type" scope makes that change
This also brings the code in line with the fsck_set_msg_type()
function (also added in 0282f4dced), which does a similar check for
"!options->msg_type". Another minor benefit is getting rid of the
style violation of not having braces for the body of the "if".
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Rename the remaining variables of type fsck_msg_id from "id" to
"msg_id". This change is relatively small, and is worth the churn for
a later change where we have different id's in the "report" function.
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Remove the append_msg_id() function in favor of calling
prepare_msg_ids(). We already have code to compute the camel-cased
msg_id strings in msg_id_info, let's use it.
When the append_msg_id() function was added in 71ab8fa840 (fsck:
report the ID of the error/warning, 2015-06-22) the prepare_msg_ids()
function didn't exist. When prepare_msg_ids() was added in
a46baac61e (fsck: factor out msg_id_info[] lazy initialization code,
2018-05-26) this code wasn't moved over to lazy initialization.
This changes the behavior of the code to initialize all the messages
instead of just camel-casing the one we need on the fly. Since the
common case is that we're printing just one message this is mostly
redundant work.
But that's OK in this case, reporting this fsck issue to the user
isn't performance-sensitive. If we were somehow doing so in a tight
loop (in a hopelessly broken repository?) this would help, since we'd
save ourselves from re-doing this work for identical messages, we
could just grab the prepared string from msg_id_info after the first
invocation.
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Rename variables in a function added in 0282f4dced (fsck: offer a
function to demote fsck errors to warnings, 2015-06-22).
It was needlessly confusing that it took a "msg_type" argument, but
then later declared another "msg_type" of a different type.
Let's rename that to "severity", and rename "id" to "msg_id" and
"msg_id" to "msg_id_str" etc. This will make a follow-up change
smaller.
While I'm at it properly indent the fsck_set_msg_type() argument list.
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Refactor code I recently changed in 1f3299fda9 (fsck: make
fsck_config() re-usable, 2021-01-05) so that I could use fsck's config
callback in mktag in 1f3299fda9 (fsck: make fsck_config() re-usable,
2021-01-05).
I don't know what I was thinking in structuring the code this way, but
it clearly makes no sense to have an fsck_config_internal() at all
just so it can get a fsck_options when git_config() already supports
passing along some void* data.
Let's just make use of that instead, which gets us rid of the two
wrapper functions, and brings fsck's common config callback in line
with other such reusable config callbacks.
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The approach to "fsck" the incoming objects in "index-pack" is
attractive for performance reasons (we have them already in core,
inflated and ready to be inspected), but fundamentally cannot be
applied fully when we receive more than one pack stream, as a tree
object in one pack may refer to a blob object in another pack as
".gitmodules", when we want to inspect blobs that are used as
".gitmodules" file, for example. Teach "index-pack" to emit
objects that must be inspected later and check them in the calling
"fetch-pack" process.
* jt/transfer-fsck-across-packs:
fetch-pack: print and use dangling .gitmodules
fetch-pack: with packfile URIs, use index-pack arg
http-fetch: allow custom index-pack args
http: allow custom index-pack args
Teach index-pack to print dangling .gitmodules links after its "keep" or
"pack" line instead of declaring an error, and teach fetch-pack to check
such lines printed.
This allows the tree side of the .gitmodules link to be in one packfile
and the blob side to be in another without failing the fsck check,
because it is now fetch-pack which checks such objects after all
packfiles have been downloaded and indexed (and not index-pack on an
individual packfile, as it is before this commit).
Signed-off-by: Jonathan Tan <jonathantanmy@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Fix "git fsck --name-objects" which apparently has not been used by
anybody who is motivated enough to report breakage.
* js/fsck-name-objects-fix:
fsck --name-objects: be more careful parsing generation numbers
t1450: robustify `remove_object()`
In 7b35efd734 (fsck_walk(): optionally name objects on the go,
2016-07-17), the `fsck` machinery learned to optionally name the
objects, so that it is easier to see what part of the repository is in a
bad shape, say, when objects are missing.
To save on complexity, this machinery uses a parser to determine the
name of a parent given a commit's name: any `~<n>` suffix is parsed and
the parent's name is formed from the prefix together with `~<n+1>`.
However, this parser has a bug: if it finds a suffix `<n>` that is _not_
`~<n>`, it will mistake the empty string for the prefix and `<n>` for
the generation number. In other words, it will generate a name of the
form `~<bogus-number>`.
Let's fix this.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Newline characters in the host and path part of git:// URL are
now forbidden.
* jk/forbid-lf-in-git-url:
fsck: reject .gitmodules git:// urls with newlines
git_connect_git(): forbid newlines in host and path
Newline characters in the host and path part of git:// URL are
now forbidden.
* jk/forbid-lf-in-git-url:
fsck: reject .gitmodules git:// urls with newlines
git_connect_git(): forbid newlines in host and path
The previous commit taught the clone/fetch client side to reject a
git:// URL with a newline in it. Let's also catch these when fscking a
.gitmodules file, which will give an earlier warning.
Note that it would be simpler to just complain about newline in _any_
URL, but an earlier tightening for http/ftp made sure we kept allowing
newlines for unknown protocols (and this is covered in the tests). So
we'll stick to that precedent.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Change mktag's acceptance rules to accept an empty body without an
empty line after the header again. This fixes an ancient unintended
dregression in "mktag".
When "mktag" was introduced in ec4465adb3 (Add "tag" objects that can
be used to sign other objects., 2005-04-25) the input checks were much
looser. When it was documented it 6cfec03680 (mktag: minimally update
the description., 2007-06-10) it was clearly intended for this \n to
be optional:
The message, when [it] exists, is separated by a blank line from
the header.
But then in e0aaf781f6 (mktag.c: improve verification of tagger field
and tests, 2008-03-27) this was made an error, seemingly by
accident. It was just a result of the general header checks, and all
the tests after that patch have a trailing empty line (but did not
before).
Let's allow this again, and tweak the test semantics changed in
e0aaf781f6 to remove the redundant empty line. New tests added in
previous commits of mine already added an explicit test for allowing
the empty line between header and body.
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Move the fsck_config() function from builtin/fsck.c to fsck.[ch]. This
allows for re-using it in other tools that expose fsck logic and want
to support its configuration variables.
A logical continuation of this change would be to use a common
function for all of {fetch,receive}.fsck.* and fsck.*. See
5d477a334a (fsck (receive-pack): allow demoting errors to warnings,
2015-06-22) and my own 1362df0d41 (fetch: implement fetch.fsck.*,
2018-07-27) for the relevant code.
However, those routines want to not parse the fsck.skipList into OIDs,
but rather pass them along with the --strict option to another
process. It would be possible to refactor that whole thing so we
support e.g. a "fetch." prefix, then just keep track of the skiplist
as a filename instead of parsing it, and learn to spew that all out
from our internal structures into something we can append to the
--strict option.
But instead I'm planning to re-use this in "mktag", which'll just
re-use these "fsck.*" variables as-is.
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Change the validation logic in "mktag" to use fsck's fsck_tag()
instead of its own custom parser. Curiously the logic for both dates
back to the same commit[1]. Let's unify them so we're not maintaining
two sets functions to verify that a tag is OK.
The behavior of fsck_tag() and the old "mktag" code being removed here
is different in few aspects.
I think it makes sense to remove some of those checks, namely:
A. fsck only cares that the timezone matches [-+][0-9]{4}. The mktag
code disallowed values larger than 1400.
Yes there's currently no timezone with a greater offset[2], but
since we allow any number of non-offical timezones (e.g. +1234)
passing this through seems fine. Git also won't break in the
future if e.g. French Polynesia decides it needs to outdo the Line
Islands when it comes to timezone extravagance.
B. fsck allows missing author names such as "tagger <email>", mktag
wouldn't, but would allow e.g. "tagger [2 spaces] <email>" (but
not "tagger [1 space] <email>"). Now we allow all of these.
C. Like B, but "mktag" disallowed spaces in the <email> part, fsck
allows it.
In some ways fsck_tag() is stricter than "mktag" was, namely:
D. fsck disallows zero-padded dates, but mktag didn't care. So
e.g. the timestamp "0000000000 +0000" produces an error now. A
test in "t1006-cat-file.sh" relied on this, it's been changed to
use "hash-object" (without fsck) instead.
There was one check I deemed worth keeping by porting it over to
fsck_tag():
E. "mktag" did not allow any custom headers, and by extension (as an
empty commit is allowed) also forbade an extra stray trailing
newline after the headers it knew about.
Add a new check in the "ignore" category to fsck and use it. This
somewhat abuses the facility added in efaba7cc77 (fsck:
optionally ignore specific fsck issues completely, 2015-06-22).
This is somewhat of hack, but probably the least invasive change
we can make here. The fsck command will shuffle these categories
around, e.g. under --strict the "info" becomes a "warn" and "warn"
becomes "error". Existing users of fsck's (and others,
e.g. index-pack) --strict option rely on this.
So we need to put something into a category that'll be ignored by
all existing users of the API. Pretending that
fsck.extraHeaderEntry=error ("ignore" by default) was set serves
to do this for us.
1. ec4465adb3 (Add "tag" objects that can be used to sign other
objects., 2005-04-25)
2. https://en.wikipedia.org/wiki/List_of_UTC_time_offsets
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The check in "git fsck" to ensure that the tree objects are sorted
still had corner cases it missed unsorted entries.
* rs/fsck-duplicate-names-in-trees:
fsck: detect more in-tree d/f conflicts
t1450: demonstrate undetected in-tree d/f conflict
t1450: increase test coverage of in-tree d/f detection
fsck: fix a typo in a comment
If the conflict candidate file name from the top of the stack is not a
prefix of the current candiate directory then we can discard it as no
matching directory can come up later. But we are not done checking the
candidate directory -- the stack might still hold a matching file name,
so stay in the loop and check the next candidate file name.
Signed-off-by: René Scharfe <l.s.r@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
"git fsck" ensures that the paths recorded in tree objects are
sorted and without duplicates, but it failed to notice a case where
a blob is followed by entries that sort before a tree with the same
name. This has been corrected.
* rs/fsck-duplicate-names-in-trees:
fsck: report non-consecutive duplicate names in trees
Tree entries are sorted in path order, meaning that directory names get
a slash ('/') appended implicitly. Git fsck checks if trees contains
consecutive duplicates, but due to that ordering there can be
non-consecutive duplicates as well if one of them is a directory and the
other one isn't. Such a tree cannot be fully checked out.
Find these duplicates by recording candidate file names on a stack and
check candidate directory names against that stack to find matches.
Suggested-by: Brandon Williams <bwilliamseng@gmail.com>
Original-test-by: Brandon Williams <bwilliamseng@gmail.com>
Signed-off-by: René Scharfe <l.s.r@web.de>
Reviewed-by: Luke Diamand <luke@diamand.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The config API made mixed uses of int and size_t types to represent
length of various pieces of text it parsed, which has been updated
to use the correct type (i.e. size_t) throughout.
* jk/config-use-size-t:
config: reject parsing of files over INT_MAX
config: use size_t to store parsed variable baselen
git_config_parse_key(): return baselen as size_t
config: drop useless length variable in write_pair()
parse_config_key(): return subsection len as size_t
remote: drop auto-strlen behavior of make_branch() and make_rewrite()
Git's URL parser interprets
https:///example.com/repo.git
to have no host and a path of "example.com/repo.git". Curl, on the
other hand, internally redirects it to https://example.com/repo.git. As
a result, until "credential: parse URL without host as empty host, not
unset", tricking a user into fetching from such a URL would cause Git to
send credentials for another host to example.com.
Teach fsck to block and detect .gitmodules files using such a URL to
prevent sharing them with Git versions that are not yet protected.
A relative URL in a .gitmodules file could also be used to trigger this.
The relative URL resolver used for .gitmodules does not normalize
sequences of slashes and can follow ".." components out of the path part
and to the host part of a URL, meaning that such a relative URL can be
used to traverse from a https://foo.example.com/innocent superproject to
a https:///attacker.example.com/exploit submodule. Fortunately,
redundant extra slashes in .gitmodules are rare, so we can catch this by
detecting one after a leading sequence of "./" and "../" components.
Helped-by: Jeff King <peff@peff.net>
Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Reviewed-by: Jeff King <peff@peff.net>
libcurl permits making requests without a URL scheme specified. In
this case, it guesses the URL from the hostname, so I can run
git ls-remote http::ftp.example.com/path/to/repo
and it would make an FTP request.
Any user intentionally using such a URL is likely to have made a typo.
Unfortunately, credential_from_url is not able to determine the host and
protocol in order to determine appropriate credentials to send, and
until "credential: refuse to operate when missing host or protocol",
this resulted in another host's credentials being leaked to the named
host.
Teach credential_from_url_gently to consider such a URL to be invalid
so that fsck can detect and block gitmodules files with such URLs,
allowing server operators to avoid serving them to downstream users
running older versions of Git.
This also means that when such URLs are passed on the command line, Git
will print a clearer error so affected users can switch to the simpler
URL that explicitly specifies the host and protocol they intend.
One subtlety: .gitmodules files can contain relative URLs, representing
a URL relative to the URL they were cloned from. The relative URL
resolver used for .gitmodules can follow ".." components out of the path
part and past the host part of a URL, meaning that such a relative URL
can be used to traverse from a https://foo.example.com/innocent
superproject to a https::attacker.example.com/exploit submodule.
Fortunately a leading ':' in the first path component after a series of
leading './' and '../' components is unlikely to show up in other
contexts, so we can catch this by detecting that pattern.
Reported-by: Jeff King <peff@peff.net>
Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Reviewed-by: Jeff King <peff@peff.net>
In 07259e74ec (fsck: detect gitmodules URLs with embedded newlines,
2020-03-11), git fsck learned to check whether URLs in .gitmodules could
be understood by the credential machinery when they are handled by
git-remote-curl.
However, the check is overbroad: it checks all URLs instead of only
URLs that would be passed to git-remote-curl. In principle a git:// or
file:/// URL does not need to follow the same conventions as an http://
URL; in particular, git:// and file:// protocols are not succeptible to
issues in the credential API because they do not support attaching
credentials.
In the HTTP case, the URL in .gitmodules does not always match the URL
that would be passed to git-remote-curl and the credential machinery:
Git's URL syntax allows specifying a remote helper followed by a "::"
delimiter and a URL to be passed to it, so that
git ls-remote http::https://example.com/repo.git
invokes git-remote-http with https://example.com/repo.git as its URL
argument. With today's checks, that distinction does not make a
difference, but for a check we are about to introduce (for empty URL
schemes) it will matter.
.gitmodules files also support relative URLs. To ensure coverage for the
https based embedded-newline attack, urldecode and check them directly
for embedded newlines.
Helped-by: Jeff King <peff@peff.net>
Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Reviewed-by: Jeff King <peff@peff.net>
We return the length to a subset of a string using an "int *"
out-parameter. This is fine most of the time, as we'd expect config keys
to be relatively short, but it could behave oddly if we had a gigantic
config key. A more appropriate type is size_t.
Let's switch over, which lets our callers use size_t as appropriate
(they are bound by our type because they must pass the out-parameter as
a pointer). This is mostly just a cleanup to make it clear this code
handles long strings correctly. In practice, our config parser already
chokes on long key names (because of a similar int/size_t mixup!).
When doing an int/size_t conversion, we have to be careful that nobody
was trying to assign a negative value to the variable. I manually
confirmed that for each case here. They tend to just feed the result to
xmemdupz() or similar; in a few cases I adjusted the parameter types for
helper functions to make sure the size_t is preserved.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The credential protocol can't handle values with newlines. We already
detect and block any such URLs from being used with credential helpers,
but let's also add an fsck check to detect and block gitmodules files
with such URLs. That will let us notice the problem earlier when
transfer.fsckObjects is turned on. And in particular it will prevent bad
objects from spreading, which may protect downstream users running older
versions of Git.
We'll file this under the existing gitmodulesUrl flag, which covers URLs
with option injection. There's really no need to distinguish the exact
flaw in the URL in this context. Likewise, I've expanded the description
of t7416 to cover all types of bogus URLs.
* maint-2.22: (43 commits)
Git 2.22.2
Git 2.21.1
mingw: sh arguments need quoting in more circumstances
mingw: fix quoting of empty arguments for `sh`
mingw: use MSYS2 quoting even when spawning shell scripts
mingw: detect when MSYS2's sh is to be spawned more robustly
t7415: drop v2.20.x-specific work-around
Git 2.20.2
t7415: adjust test for dubiously-nested submodule gitdirs for v2.20.x
Git 2.19.3
Git 2.18.2
Git 2.17.3
Git 2.16.6
test-drop-caches: use `has_dos_drive_prefix()`
Git 2.15.4
Git 2.14.6
mingw: handle `subst`-ed "DOS drives"
mingw: refuse to access paths with trailing spaces or periods
mingw: refuse to access paths with illegal characters
unpack-trees: let merged_entry() pass through do_add_entry()'s errors
...
* maint-2.21: (42 commits)
Git 2.21.1
mingw: sh arguments need quoting in more circumstances
mingw: fix quoting of empty arguments for `sh`
mingw: use MSYS2 quoting even when spawning shell scripts
mingw: detect when MSYS2's sh is to be spawned more robustly
t7415: drop v2.20.x-specific work-around
Git 2.20.2
t7415: adjust test for dubiously-nested submodule gitdirs for v2.20.x
Git 2.19.3
Git 2.18.2
Git 2.17.3
Git 2.16.6
test-drop-caches: use `has_dos_drive_prefix()`
Git 2.15.4
Git 2.14.6
mingw: handle `subst`-ed "DOS drives"
mingw: refuse to access paths with trailing spaces or periods
mingw: refuse to access paths with illegal characters
unpack-trees: let merged_entry() pass through do_add_entry()'s errors
quote-stress-test: offer to test quoting arguments for MSYS2 sh
...
* maint-2.20: (36 commits)
Git 2.20.2
t7415: adjust test for dubiously-nested submodule gitdirs for v2.20.x
Git 2.19.3
Git 2.18.2
Git 2.17.3
Git 2.16.6
test-drop-caches: use `has_dos_drive_prefix()`
Git 2.15.4
Git 2.14.6
mingw: handle `subst`-ed "DOS drives"
mingw: refuse to access paths with trailing spaces or periods
mingw: refuse to access paths with illegal characters
unpack-trees: let merged_entry() pass through do_add_entry()'s errors
quote-stress-test: offer to test quoting arguments for MSYS2 sh
t6130/t9350: prepare for stringent Win32 path validation
quote-stress-test: allow skipping some trials
quote-stress-test: accept arguments to test via the command-line
tests: add a helper to stress test argument quoting
mingw: fix quoting of arguments
Disallow dubiously-nested submodule git directories
...
* maint-2.19: (34 commits)
Git 2.19.3
Git 2.18.2
Git 2.17.3
Git 2.16.6
test-drop-caches: use `has_dos_drive_prefix()`
Git 2.15.4
Git 2.14.6
mingw: handle `subst`-ed "DOS drives"
mingw: refuse to access paths with trailing spaces or periods
mingw: refuse to access paths with illegal characters
unpack-trees: let merged_entry() pass through do_add_entry()'s errors
quote-stress-test: offer to test quoting arguments for MSYS2 sh
t6130/t9350: prepare for stringent Win32 path validation
quote-stress-test: allow skipping some trials
quote-stress-test: accept arguments to test via the command-line
tests: add a helper to stress test argument quoting
mingw: fix quoting of arguments
Disallow dubiously-nested submodule git directories
protect_ntfs: turn on NTFS protection by default
path: also guard `.gitmodules` against NTFS Alternate Data Streams
...
* maint-2.18: (33 commits)
Git 2.18.2
Git 2.17.3
Git 2.16.6
test-drop-caches: use `has_dos_drive_prefix()`
Git 2.15.4
Git 2.14.6
mingw: handle `subst`-ed "DOS drives"
mingw: refuse to access paths with trailing spaces or periods
mingw: refuse to access paths with illegal characters
unpack-trees: let merged_entry() pass through do_add_entry()'s errors
quote-stress-test: offer to test quoting arguments for MSYS2 sh
t6130/t9350: prepare for stringent Win32 path validation
quote-stress-test: allow skipping some trials
quote-stress-test: accept arguments to test via the command-line
tests: add a helper to stress test argument quoting
mingw: fix quoting of arguments
Disallow dubiously-nested submodule git directories
protect_ntfs: turn on NTFS protection by default
path: also guard `.gitmodules` against NTFS Alternate Data Streams
is_ntfs_dotgit(): speed it up
...
* maint-2.17: (32 commits)
Git 2.17.3
Git 2.16.6
test-drop-caches: use `has_dos_drive_prefix()`
Git 2.15.4
Git 2.14.6
mingw: handle `subst`-ed "DOS drives"
mingw: refuse to access paths with trailing spaces or periods
mingw: refuse to access paths with illegal characters
unpack-trees: let merged_entry() pass through do_add_entry()'s errors
quote-stress-test: offer to test quoting arguments for MSYS2 sh
t6130/t9350: prepare for stringent Win32 path validation
quote-stress-test: allow skipping some trials
quote-stress-test: accept arguments to test via the command-line
tests: add a helper to stress test argument quoting
mingw: fix quoting of arguments
Disallow dubiously-nested submodule git directories
protect_ntfs: turn on NTFS protection by default
path: also guard `.gitmodules` against NTFS Alternate Data Streams
is_ntfs_dotgit(): speed it up
mingw: disallow backslash characters in tree objects' file names
...
This allows hosting providers to detect whether they are being used
to attack users using malicious 'update = !command' settings in
.gitmodules.
Since ac1fbbda20 (submodule: do not copy unknown update mode from
.gitmodules, 2013-12-02), in normal cases such settings have been
treated as 'update = none', so forbidding them should not produce any
collateral damage to legitimate uses. A quick search does not reveal
any repositories making use of this construct, either.
Reported-by: Joern Schneeweisz <jschneeweisz@gitlab.com>
Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
* maint-2.16: (31 commits)
Git 2.16.6
test-drop-caches: use `has_dos_drive_prefix()`
Git 2.15.4
Git 2.14.6
mingw: handle `subst`-ed "DOS drives"
mingw: refuse to access paths with trailing spaces or periods
mingw: refuse to access paths with illegal characters
unpack-trees: let merged_entry() pass through do_add_entry()'s errors
quote-stress-test: offer to test quoting arguments for MSYS2 sh
t6130/t9350: prepare for stringent Win32 path validation
quote-stress-test: allow skipping some trials
quote-stress-test: accept arguments to test via the command-line
tests: add a helper to stress test argument quoting
mingw: fix quoting of arguments
Disallow dubiously-nested submodule git directories
protect_ntfs: turn on NTFS protection by default
path: also guard `.gitmodules` against NTFS Alternate Data Streams
is_ntfs_dotgit(): speed it up
mingw: disallow backslash characters in tree objects' file names
path: safeguard `.git` against NTFS Alternate Streams Accesses
...
* maint-2.14: (28 commits)
Git 2.14.6
mingw: handle `subst`-ed "DOS drives"
mingw: refuse to access paths with trailing spaces or periods
mingw: refuse to access paths with illegal characters
unpack-trees: let merged_entry() pass through do_add_entry()'s errors
quote-stress-test: offer to test quoting arguments for MSYS2 sh
t6130/t9350: prepare for stringent Win32 path validation
quote-stress-test: allow skipping some trials
quote-stress-test: accept arguments to test via the command-line
tests: add a helper to stress test argument quoting
mingw: fix quoting of arguments
Disallow dubiously-nested submodule git directories
protect_ntfs: turn on NTFS protection by default
path: also guard `.gitmodules` against NTFS Alternate Data Streams
is_ntfs_dotgit(): speed it up
mingw: disallow backslash characters in tree objects' file names
path: safeguard `.git` against NTFS Alternate Streams Accesses
clone --recurse-submodules: prevent name squatting on Windows
is_ntfs_dotgit(): only verify the leading segment
test-path-utils: offer to run a protectNTFS/protectHFS benchmark
...
The config setting `core.protectNTFS` is specifically designed to work
not only on Windows, but anywhere, to allow for repositories hosted on,
say, Linux servers to be protected against NTFS-specific attack vectors.
As a consequence, `is_ntfs_dotgit()` manually splits backslash-separated
paths (but does not do the same for paths separated by forward slashes),
under the assumption that the backslash might not be a valid directory
separator on the _current_ Operating System.
However, the two callers, `verify_path()` and `fsck_tree()`, are
supposed to feed only individual path segments to the `is_ntfs_dotgit()`
function.
This causes a lot of duplicate scanning (and very inefficient scanning,
too, as the inner loop of `is_ntfs_dotgit()` was optimized for
readability rather than for speed.
Let's simplify the design of `is_ntfs_dotgit()` by putting the burden of
splitting the paths by backslashes as directory separators on the
callers of said function.
Consequently, the `verify_path()` function, which already splits the
path by directory separators, now treats backslashes as directory
separators _explicitly_ when `core.protectNTFS` is turned on, even on
platforms where the backslash is _not_ a directory separator.
Note that we have to repeat some code in `verify_path()`: if the
backslash is not a directory separator on the current Operating System,
we want to allow file names like `\`, but we _do_ want to disallow paths
that are clearly intended to cause harm when the repository is cloned on
Windows.
The `fsck_tree()` function (the other caller of `is_ntfs_dotgit()`) now
needs to look for backslashes in tree entries' names specifically when
`core.protectNTFS` is turned on. While it would be tempting to
completely disallow backslashes in that case (much like `fsck` reports
names containing forward slashes as "full paths"), this would be
overzealous: when `core.protectNTFS` is turned on in a non-Windows
setup, backslashes are perfectly valid characters in file names while we
_still_ want to disallow tree entries that are clearly designed to
exploit NTFS-specific behavior.
This simplification will make subsequent changes easier to implement,
such as turning `core.protectNTFS` on by default (not only on Windows)
or protecting against attack vectors involving NTFS Alternate Data
Streams.
Incidentally, this change allows for catching malicious repositories
that contain tree entries of the form `dir\.gitmodules` already on the
server side rather than only on the client side (and previously only on
Windows): in contrast to `is_ntfs_dotgit()`, the
`is_ntfs_dotgitmodules()` function already expects the caller to split
the paths by directory separators.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
We don't actually look at the tree struct in fsck_tree() beyond its oid
and type (which is obviously OBJ_TREE). Just taking an oid gives our
callers more flexibility to avoid creating a struct, and makes it clear
that we are fscking just what is in the buffer, not any pre-parsed bits
from the struct.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
We don't actually look at the commit struct in fsck_commit() beyond its
oid and type (which is obviously OBJ_COMMIT). Just taking an oid gives
our callers more flexibility to avoid creating or parsing a struct, and
makes it clear that we are fscking just what is in the buffer, not any
pre-parsed bits from the struct.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
We don't actually look at the tag struct in fsck_tag() beyond its oid
and type (which is obviously OBJ_TAG). Just taking an oid gives our
callers more flexibility to avoid creating or parsing a struct, and
makes it clear that we are fscking just what is in the buffer, not any
pre-parsed bits from the struct.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
In fsck_commit() and fsck_tag(), we have local "oid" variables used for
parsing parent and tagged-object oids. Let's give these more specific
names in preparation for the functions taking an "oid" parameter for the
object we're checking.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
We only need the oid and type to pass on to report(). Let's accept the
broken-out parameters to give our callers more flexibility.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The only thing we do with the struct is pass its oid and type to
report(). We can just take those explicitly, which gives our callers
more flexibility.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Since fsck_blob() no longer requires us to have a "struct blob", we
don't need to create one. Which also means we don't need to worry about
handling the case that lookup_blob() returns NULL (we'll still catch
wrongly-identified blobs when we read the actual object contents and
type from disk).
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
We don't actually need any information from the object struct except its
oid (and the type, of course, but that's implicitly OBJ_BLOB). This
gives our callers more flexibility to drop the object structs, too.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The report() function really only cares about the oid and type of the
object, not the full object struct. Let's convert it to take those two
items separately, which gives our callers more flexibility.
This makes some already-long lines even longer. I've mostly left them,
as our eventual goal is to shrink these down as we continue refactoring
(e.g., "&item->object" becomes "&item->object.oid, item->object.type",
but will eventually shrink down to "oid, type").
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The skiplist is inherently an oidset, so we don't need a full object
struct. Let's take just the oid to give our callers more flexibility.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
None of the callbacks actually care about having a "struct object";
they're happy with just the oid and type information. So let's give
ourselves more flexibility to avoid having a "struct object" by just
passing the broken-down fields.
Note that the callback already takes a "type" field for the fsck message
type. We'll rename that to "msg_type" (and use "object_type" for the
object type) to make the distinction explicit.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
We don't actually care about having object structs; we only need to look
up decorations by oid. Let's accept this more limited form, which will
give our callers more flexibility.
Note that the decoration API we rely on uses object structs itself (even
though it only looks at their oids). We can solve this by switching to
a kh_oid_map (we could also use the hashmap oidmap, but it's more
awkward for the simple case of just storing a void pointer).
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This isolates the implementation detail of using the decoration code to
our put/get functions.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Commit 90cf590f53 (fsck: optionally show more helpful info for broken
links, 2016-07-17) added a system for decorating objects with names. The
code is split across builtin/fsck.c (which gives the initial names) and
fsck.c (which adds to the names as it traverses the object graph). This
leads to some duplication, where both sites have near-identical
describe_object() functions (the difference being that the one in
builtin/fsck.c uses a circular array of buffers to allow multiple calls
in a single printf).
Let's provide a unified object_name API for fsck. That lets us drop the
duplication, as well as making the interface boundaries more clear
(which will let us refactor the implementation more in a future patch).
We'll leave describe_object() in builtin/fsck.c as a thin wrapper around
the new API, as it relies on a static global to make its many callers a
bit shorter.
We'll also convert the bare add_decoration() calls in builtin/fsck.c to
put_object_name(). This fixes two minor bugs:
1. We leak many small strings. add_decoration() has a last-one-wins
approach: it updates the decoration to the new string and returns
the old one. But we ignore the return value, leaking the old
string. This is quite common to trigger, since we look at reflogs:
the tip of any ref will be described both by looking at the actual
ref, as well as the latest reflog entry. So we'd always end up
leaking one of those strings.
2. The last-one-wins approach gives us lousy names. For instance, we
first look at all of the refs, and then all of the reflogs. So
rather than seeing "refs/heads/master", we're likely to overwrite
it with "HEAD@{12345678}". We're generally better off using the
first name we find.
And indeed, the test in t1450 expects this ugly HEAD@{} name. After
this patch, we've switched to using fsck_put_object_name()'s
first-one-wins semantics, and we output the more human-friendly
"refs/tags/julius" (and the test is updated accordingly).
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The fsck_object() function takes in a buffer, but also a "struct
object". The rules for using these vary between types:
- for a commit, we'll use the provided buffer; if it's NULL, we'll
fall back to get_commit_buffer(), which loads from either an
in-memory cache or from disk. If the latter fails, we'd die(), which
is non-ideal for fsck.
- for a tag, a NULL buffer will fall back to loading the object from
disk (and failure would lead to an fsck error)
- for a tree, we _never_ look at the provided buffer, and always use
tree->buffer
- for a blob, we usually don't look at the buffer at all, unless it
has been marked as a .gitmodule file. In that case we check the
buffer given to us, or assume a NULL buffer is a very large blob
(and complain about it)
This is much more complex than it needs to be. It turns out that nobody
ever feeds a NULL buffer that isn't a blob:
- git-fsck calls fsck_object() only from fsck_obj(). That in turn is
called by one of:
- fsck_obj_buffer(), which is a callback to verify_pack(), which
unpacks everything except large blobs into a buffer (see
pack-check.c, lines 131-141).
- fsck_loose(), which hits a BUG() on non-blobs with a NULL buffer
(builtin/fsck.c, lines 639-640)
And in either case, we'll have just called parse_object_buffer()
anyway, which would segfault on a NULL buffer for commits or tags
(not for trees, but it would install a NULL tree->buffer which would
later cause a segfault)
- git-index-pack asserts that the buffer is non-NULL unless the object
is a blob (see builtin/index-pack.c, line 832)
- git-unpack-objects always writes a non-NULL buffer into its
obj_buffer hash, which is then fed to fsck_object(). (There is
actually a funny thing here where it does not store blob buffers at
all, nor does it call fsck on them; it does check any needed blobs
via fsck_finish() though).
Let's make the rules simpler, which reduces the amount of code and gives
us more flexibility in refactoring the fsck code. The new rules are:
- only blobs are allowed to pass a NULL buffer
- we always use the provided buffer, never pulling information from
the object struct
We don't have to adjust any callers, because they were already adhering
to these. Note that we do drop a few fsck identifiers for missing tags,
but that was all dead code (because nobody passed a NULL tag buffer).
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Way back in 92d4c85d24 (fsck-cache: fix SIGSEGV on bad tag object,
2005-05-03), we added an fsck check that the "tagged" field of a tag
struct isn't NULL. But that was mainly protecting the printing code for
"--tags", and that code wasn't moved along with the check as part of
ba002f3b28 (builtin-fsck: move common object checking code to fsck.c,
2008-02-25).
It could also serve to detect type mismatch problems (where a tag points
to object X as a commit, but really X is a blob), but it couldn't do so
reliably (we'd call lookup_commit(X), but it will only notice the
problem if we happen to have previously called lookup_blob(X) in the
same process). And as of a commit earlier in this series, we'd consider
that a parse error and complain about the object even before getting to
this point anyway.
So let's drop this "tag->tagged" check. It's not helping anything, and
getting rid of it makes the function conceptually cleaner, as it really
is just checking the buffer we feed it. In fact, we can get rid of our
one-line wrapper and just unify fsck_tag() and fsck_tag_buffer().
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
In 4516338243 (builtin-fsck: reports missing parent commits,
2008-02-25), we added code to check that fsck found the same number of
parents from parsing the commit itself as we see in the commit struct we
got from parse_commit_buffer(). Back then the rationale was that the
normal commit parser might skip some bad parents.
But earlier in this series, we started treating that reliably as a
parsing error, meaning that we'd complain about it before we even hit
the code in fsck.c.
Let's drop this code, which now makes fsck_commit_buffer() completely
independent of any parsed values in the commit struct (that's
conceptually cleaner, and also opens up more refactoring options).
Note that we can also drop the MISSING_PARENT and MISSING_GRAFT fsck
identifiers. This is no loss, as these would not trigger reliably
anyway. We'd hit them only when lookup_commit() failed, which occurs
only if we happen to have seen the object with another type already in
the same process. In most cases, we'd actually run into the problem
during the connectivity walk, not here.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
We check in fsck_commit_buffer() that commit->tree isn't NULL, which in
turn generally comes from a previous parse by parse_commit(). But this
isn't really accomplishing anything. The two things we might care about
are:
- was there a syntactically valid "tree <oid>" line in the object? But
we've just done our own parse in fsck_commit_buffer() to check this.
- does it point to a valid tree object? But checking the "tree"
pointer here doesn't actually accomplish that; it just shows that
lookup_tree() didn't return NULL, which only means that we haven't
yet seen that oid as a non-tree in this process.
A real connectivity check would exhaustively walk all graph links,
and we do that already in a separate function.
So this code isn't helping anything. And it makes the fsck code slightly
more confusing and rigid (e.g., it requires that any commit structs have
already been parsed). Let's drop it.
As a bit of history, the presence of this code looks like a leftover
from early fsck code (which did rely on parse_commit() to do most of the
parsing). The check comes from ff5ebe39b0 (Port fsck-cache to use
parsing functions, 2005-04-18), but we later added an explicit walk in
355885d531 (add generic, type aware object chain walker, 2008-02-25).
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
"git blame" learned to "ignore" commits in the history, whose
effects (as well as their presence) get ignored.
* br/blame-ignore:
t8014: remove unnecessary braces
blame: drop some unused function parameters
blame: add a test to cover blame_coalesce()
blame: use the fingerprint heuristic to match ignored lines
blame: add a fingerprint heuristic to match ignored lines
blame: optionally track line fingerprints during fill_blame_origin()
blame: add config options for the output of ignored or unblamable lines
blame: add the ability to ignore commits and their changes
blame: use a helper function in blame_chunk()
Move oidset_parse_file() to oidset.c
fsck: rename and touch up init_skiplist()
There are no callers left of lookup_unknown_object() that aren't just
passing us the "hash" member of a "struct object_id". Let's take the
whole struct, which gets us closer to removing all raw sha1 variables.
It also matches the existing conversions of lookup_blob(), etc.
The conversions of callers were done by hand, but they're all mechanical
one-liners.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
init_skiplist() took a file consisting of SHA-1s and comments and added
the objects to an oidset. This functionality is useful for other
commands and will be moved to oidset.c in a future commit.
In preparation for that move, this commit renames it to
oidset_parse_file() to reflect its more generic usage and cleans up a
few of the names.
Signed-off-by: Barret Rhoden <brho@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
struct diff_filespec defines mode to be an 'unsigned short'. Several
other places in the API which we'd like to interact with using a
diff_filespec used a plain unsigned (or unsigned int). This caused
problems when taking addresses, so switch to unsigned short.
Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When parsing a tree, we read the object ID directly out of the tree
buffer. This is normally fine, but such an object ID cannot be used with
oidcpy, which copies GIT_MAX_RAWSZ bytes, because if we are using SHA-1,
there may not be that many bytes to copy.
Instead, store the object ID in a separate struct member. Since we can
no longer efficiently compute the path length, store that information as
well in struct name_entry. Ensure we only copy the object ID into the
new buffer if the path length is nonzero, as some callers will pass us
an empty path with no object ID following it, and we will not want to
read past the end of the buffer.
Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
