git/connect.c, branch v2.32.2

hash: provide per-algorithm null OIDs

2021-04-27T07:31:39Z

Up until recently, object IDs did not have an algorithm member, only a hash. Consequently, it was possible to share one null (all-zeros) object ID among all hash algorithms. Now that we're going to be handling objects from multiple hash algorithms, it's important to make sure that all object IDs have a correct algorithm field. Introduce a per-algorithm null OID, and add it to struct hash_algo. Introduce a wrapper function as well, and use it everywhere we used to use the null_oid constant. Signed-off-by: brian m. carlson Signed-off-by: Junio C Hamano

Merge branch 'jt/clone-unborn-head'

2021-02-18T01:21:40Z

"git clone" tries to locally check out the branch pointed at by HEAD of the remote repository after it is done, but the protocol did not convey the information necessary to do so when copying an empty repository. The protocol v2 learned how to do so. * jt/clone-unborn-head: clone: respect remote unborn HEAD connect, transport: encapsulate arg in struct ls-refs: report unborn targets of symrefs

clone: respect remote unborn HEAD

2021-02-05T21:49:55Z

Teach Git to use the "unborn" feature introduced in a previous patch as follows: Git will always send the "unborn" argument if it is supported by the server. During "git clone", if cloning an empty repository, Git will use the new information to determine the local branch to create. In all other cases, Git will ignore it. Signed-off-by: Jonathan Tan Signed-off-by: Junio C Hamano

connect, transport: encapsulate arg in struct

2021-02-05T21:49:54Z

In a future patch we plan to return the name of an unborn current branch from deep in the callchain to a caller via a new pointer parameter that points at a variable in the caller when the caller calls get_remote_refs() and transport_get_remote_refs(). In preparation for that, encapsulate the existing ref_prefixes parameter into a struct. The aforementioned unborn current branch will go into this new struct in the future patch. Signed-off-by: Jonathan Tan Signed-off-by: Junio C Hamano

Merge branch 'jk/forbid-lf-in-git-url'

2021-01-25T22:19:17Z

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

git_connect_git(): forbid newlines in host and path

2021-01-07T22:25:44Z

When we connect to a git:// server, we send an initial request that looks something like: 002dgit-upload-pack repo.git\0host=example.com If the repo path contains a newline, then it's included literally, and we get: 002egit-upload-pack repo .git\0host=example.com This works fine if you really do have a newline in your repository name; the server side uses the pktline framing to parse the string, not newlines. However, there are many _other_ protocols in the wild that do parse on newlines, such as HTTP. So a carefully constructed git:// URL can actually turn into a valid HTTP request. For example: git://localhost:1234/%0d%0a%0d%0aGET%20/%20HTTP/1.1 %0d%0aHost:localhost%0d%0a%0d%0a becomes: 0050git-upload-pack / GET / HTTP/1.1 Host:localhost host=localhost:1234 on the wire. Again, this isn't a problem for a real Git server, but it does mean that feeding a malicious URL to Git (e.g., through a submodule) can cause it to make unexpected cross-protocol requests. Since repository names with newlines are presumably quite rare (and indeed, we already disallow them in git-over-http), let's just disallow them over this protocol. Hostnames could likewise inject a newline, but this is unlikely a problem in practice; we'd try resolving the hostname with a newline in it, which wouldn't work. Still, it doesn't hurt to err on the side of caution there, since we would not expect them to work in the first place. The ssh and local code paths are unaffected by this patch. In both cases we're trying to run upload-pack via a shell, and will quote the newline so that it makes it intact. An attacker can point an ssh url at an arbitrary port, of course, but unless there's an actual ssh server there, we'd never get as far as sending our shell command anyway. We _could_ similarly restrict newlines in those protocols out of caution, but there seems little benefit to doing so. The new test here is run alongside the git-daemon tests, which cover the same protocol, but it shouldn't actually contact the daemon at all. In theory we could make the test more robust by setting up an actual repository with a newline in it (so that our clone would succeed if our new check didn't kick in). But a repo directory with newline in it is likely not portable across all filesystems. Likewise, we could check git-daemon's log that it was not contacted at all, but we do not currently record the log (and anyway, it would make the test racy with the daemon's log write). We'll just check the client-side stderr to make sure we hit the expected code path. Reported-by: Harold Kim Signed-off-by: Jeff King Signed-off-by: Junio C Hamano

Merge branch 'jk/leakfix'

2020-08-27T21:04:49Z

Code clean-up. * jk/leakfix: submodule--helper: fix leak of core.worktree value config: fix leak in git_config_get_expiry_in_days() config: drop git_config_get_string_const() config: fix leaks from git_config_get_string_const() checkout: fix leak of non-existent branch names submodule--helper: use strbuf_release() to free strbufs clear_pattern_list(): clear embedded hashmaps

config: fix leaks from git_config_get_string_const()

2020-08-14T17:52:04Z

There are two functions to get a single config string: - git_config_get_string() - git_config_get_string_const() One might naively think that the first one allocates a new string and the second one just points us to the internal configset storage. But in fact they both allocate a new copy; the second one exists only to avoid having to cast when using it with a const global which we never intend to free. The documentation for the function explains that clearly, but it seems I'm not alone in being surprised by this. Of 17 calls to the function, 13 of them leak the resulting value. We could obviously fix these by adding the appropriate free(). But it would be simpler still if we actually had a non-allocating way to get the string. There's git_config_get_value() but that doesn't quite do what we want. If the config key is present but is a boolean with no value (e.g., "[foo]bar" in the file), then we'll get NULL (whereas the string versions will print an error and die). So let's introduce a new variant, git_config_get_string_tmp(), that behaves as these callers expect. We need a new name because we have new semantics but the same function signature (so even if we converted the four remaining callers, topics in flight might be surprised). The "tmp" is because this value should only be held onto for a short time. In practice it's rare for us to clear and refresh the configset, invalidating the pointer, but hopefully the "tmp" makes callers think about the lifetime. In each of the converted cases here the value only needs to last within the local function or its immediate caller. Signed-off-by: Jeff King Signed-off-by: Junio C Hamano

strvec: rename struct fields

2020-07-31T02:18:06Z

The "argc" and "argv" names made sense when the struct was argv_array, but now they're just confusing. Let's rename them to "nr" (which we use for counts elsewhere) and "v" (which is rather terse, but reads well when combined with typical variable names like "args.v"). Note that we have to update all of the callers immediately. Playing tricks with the preprocessor is hard here, because we wouldn't want to rewrite unrelated tokens. Signed-off-by: Jeff King Signed-off-by: Junio C Hamano

strvec: fix indentation in renamed calls

2020-07-28T22:02:18Z

Code which split an argv_array call across multiple lines, like: argv_array_pushl(&args, "one argument", "another argument", "and more", NULL); was recently mechanically renamed to use strvec, which results in mis-matched indentation like: strvec_pushl(&args, "one argument", "another argument", "and more", NULL); Let's fix these up to align the arguments with the opening paren. I did this manually by sifting through the results of: git jump grep 'strvec_.*,$' and liberally applying my editor's auto-format. Most of the changes are of the form shown above, though I also normalized a few that had originally used a single-tab indentation (rather than our usual style of aligning with the open paren). I also rewrapped a couple of obvious cases (e.g., where previously too-long lines became short enough to fit on one), but I wasn't aggressive about it. In cases broken to three or more lines, the grouping of arguments is sometimes meaningful, and it wasn't worth my time or reviewer time to ponder each case individually. Signed-off-by: Jeff King Signed-off-by: Junio C Hamano