unpack-objects: add --max-input-size=<size> option

When receiving a pack-file, it can be useful to abort the
`git unpack-objects`, if the pack-file is too big.

Signed-off-by: Christian Couder <chriscool@tuxfamily.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

diff --git a/Documentation/git-unpack-objects.txt b/Documentation/git-unpack-objects.txt
index 3e887d16109c48f4f906d8a7c5c0c860bbd6123d..b3de50d7106819f4dee92b3508c7713d170832ce 100644 (file)
--- a/Documentation/git-unpack-objects.txt
+++ b/Documentation/git-unpack-objects.txt
@@ -44,6 +44,9 @@ OPTIONS
 --strict::
        Don't write objects with broken content or links.
 
+--max-input-size=<size>::
+       Die, if the pack is larger than <size>.
+
 GIT
 ---
 Part of the linkgit:git[1] suite

diff --git a/builtin/unpack-objects.c b/builtin/unpack-objects.c
index 172470bf241e4da731c5741567555d7e01691c74..4532aa083154ae7e9be07014d3761821fa6c4ddc 100644 (file)
--- a/builtin/unpack-objects.c
+++ b/builtin/unpack-objects.c
@@ -19,6 +19,7 @@ static const char unpack_usage[] = "git unpack-objects [-n] [-q] [-r] [--strict]
 static unsigned char buffer[4096];
 static unsigned int offset, len;
 static off_t consumed_bytes;
+static off_t max_input_size;
 static git_SHA_CTX ctx;
 static struct fsck_options fsck_options = FSCK_OPTIONS_STRICT;
 
@@ -87,6 +88,8 @@ static void use(int bytes)
        if (signed_add_overflows(consumed_bytes, bytes))
                die("pack too large for current definition of off_t");
        consumed_bytes += bytes;
+       if (max_input_size && consumed_bytes > max_input_size)
+               die(_("pack exceeds maximum allowed size"));
 }
 
 static void *get_data(unsigned long size)
@@ -550,6 +553,10 @@ int cmd_unpack_objects(int argc, const char **argv, const char *prefix)
                                len = sizeof(*hdr);
                                continue;
                        }
+                       if (skip_prefix(arg, "--max-input-size=", &arg)) {
+                               max_input_size = strtoumax(arg, NULL, 10);
+                               continue;
+                       }
                        usage(unpack_usage);
                }