fsck: split ".gitmodules too large" error from parse failure

Since ed8b10f631 (fsck: check .gitmodules content,
2018-05-02), we'll report a gitmodulesParse error for two
conditions:

  - a .gitmodules entry is not syntactically valid

  - a .gitmodules entry is larger than core.bigFileThreshold

with the intent that we can detect malicious files and
protect downstream clients. E.g., from the issue in
0383bbb901 (submodule-config: verify submodule names as
paths, 2018-04-30).

But these conditions are actually quite different with
respect to that bug:

 - a syntactically invalid file cannot trigger the problem,
   as the victim would barf before hitting the problematic
   code

 - a too-big .gitmodules _can_ trigger the problem. Even
   though it is obviously silly to have a 500MB .gitmodules
   file, the submodule code will happily parse it if you
   have enough memory.

So it may be reasonable to configure their severity
separately. Let's add a new class for the "too large" case
to allow that.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

diff --git a/fsck.c b/fsck.c
index 87b0e228bd091e53fc1ad201948877d324b3b881..4129935d86b64270b595c3c9d62c6096cb1e666f 100644 (file)
--- a/fsck.c
+++ b/fsck.c
@@ -63,6 +63,7 @@ static struct oidset gitmodules_done = OIDSET_INIT;
        FUNC(GITMODULES_MISSING, ERROR) \
        FUNC(GITMODULES_BLOB, ERROR) \
        FUNC(GITMODULES_PARSE, ERROR) \
+       FUNC(GITMODULES_LARGE, ERROR) \
        FUNC(GITMODULES_NAME, ERROR) \
        FUNC(GITMODULES_SYMLINK, ERROR) \
        /* warnings */ \
@@ -1005,7 +1006,7 @@ static int fsck_blob(struct blob *blob, const char *buf,
                 * that an error.
                 */
                return report(options, &blob->object,
-                             FSCK_MSG_GITMODULES_PARSE,
+                             FSCK_MSG_GITMODULES_LARGE,
                              ".gitmodules too large to parse");
        }