[PATCH 1/2] parse_commit_buffer: don't parse invalid commits
Signed-off-by: Martin Koegler <mkoegler@auto.tuwien.ac.at>
---
commit.c | 35 ++++++++++++++++++++++++-----------
1 files changed, 24 insertions(+), 11 deletions(-)
diff --git a/commit.c b/commit.c
index f074811..5b52daa 100644
--- a/commit.c
+++ b/commit.c
@@ -48,22 +48,34 @@ struct commit *lookup_commit(const unsigned char *sha1)
return check_commit(obj, sha1, 0);
}
-static unsigned long parse_commit_date(const char *buf)
+static int parse_commit_date(const char *buf, const char *tail, unsigned long *date)
{
- unsigned long date;
+ const char *dateptr;
+ if (buf + 6 >= tail)
+ return 0;
if (memcmp(buf, "author", 6))
return 0;
- while (*buf++ != '\n')
+ while (buf < tail && *buf++ != '\n')
/* nada */;
+ if (buf + 9 >= tail)
+ return 0;
if (memcmp(buf, "committer", 9))
return 0;
- while (*buf++ != '>')
+ while (buf < tail && *buf++ != '>')
/* nada */;
- date = strtoul(buf, NULL, 10);
- if (date == ULONG_MAX)
- date = 0;
- return date;
+ if (buf >= tail)
+ return 0;
+ dateptr = buf;
+ while (buf < tail && *buf++ != '\n')
+ /* nada */;
+ if (buf >= tail)
+ return 0;
+ /* dateptr < buf && buf[-1] == '\n', so strtoul will stop at buf-1 */
+ *date = strtoul(dateptr, NULL, 10);
+ if (*date == ULONG_MAX)
+ *date = 0;
+ return 1;
}
static struct commit_graft **commit_graft;
@@ -236,9 +248,9 @@ int parse_commit_buffer(struct commit *item, void *buffer, unsigned long size)
return 0;
item->object.parsed = 1;
tail += size;
- if (tail <= bufptr + 5 || memcmp(bufptr, "tree ", 5))
+ if (tail <= bufptr + 46 || memcmp(bufptr, "tree ", 5) || bufptr[45] != '\n')
return error("bogus commit object %s", sha1_to_hex(item->object.sha1));
- if (tail <= bufptr + 45 || get_sha1_hex(bufptr + 5, parent) < 0)
+ if (get_sha1_hex(bufptr + 5, parent) < 0)
return error("bad tree pointer in commit %s",
sha1_to_hex(item->object.sha1));
item->tree = lookup_tree(parent);
@@ -275,7 +287,8 @@ int parse_commit_buffer(struct commit *item, void *buffer, unsigned long size)
n_refs++;
}
}
- item->date = parse_commit_date(bufptr);
+ if (!parse_commit_date(bufptr, tail, &item->date))
+ return error("bogus commit date in object %s", sha1_to_hex(item->object.sha1));
if (track_object_refs) {
unsigned i = 0;
--
1.4.4.4