Possible segfault introduced in commit.c

Hi all,

As you might already know, we analyze git regularly with Sentry (our
static analysis tool).  Today it picked up a new NULL pointer
dereference in commit.c:366:

    void commit_list_reverse(struct commit_list **list_p)
    {
        struct commit_list *prev = NULL, *curr = *list_p, *next;

        if (!list_p)
            return;
        /* function continues... */
    }

list_p is dereferenced on the first line, then tested for NULL on
the very next statement.  If it's possible that list_p is NULL, this
will be a segfault.  If it can't be NULL, then the check is
unnecessary (and probably misleading).

Introduced here:
https://github.com/gitster/git/commit/fbc08ea

Best,
Mike

-- 
Mike Mueller
Phone: (401) 405-1525
Email: mmueller@vigilantsw.com

http://www.vigilantsw.com/