entry.c: fix possible buffer overflow in remove_subtree()

diff --git a/mailmap.c b/mailmap.c
index 4cc6e8128f73f74f260cdc66bcbbad56afe573c0..30614343213442806c5fbc28e904639d35c670cf 100644 (file)
--- a/mailmap.c
+++ b/mailmap.c
@@ -5,8 +5,10 @@
 #define DEBUG_MAILMAP 0
 #if DEBUG_MAILMAP
 #define debug_mm(...) fprintf(stderr, __VA_ARGS__)
+#define debug_str(X) ((X) ? (X) : "(none)")
 #else
 static inline void debug_mm(const char *format, ...) {}
+static inline const char *debug_str(const char *s) { return s; }
 #endif
 
 const char *git_mailmap_file;
@@ -29,7 +31,8 @@ struct mailmap_entry {
 static void free_mailmap_info(void *p, const char *s)
 {
        struct mailmap_info *mi = (struct mailmap_info *)p;
-       debug_mm("mailmap: -- complex: '%s' -> '%s' <%s>\n", s, mi->name, mi->email);
+       debug_mm("mailmap: -- complex: '%s' -> '%s' <%s>\n",
+                s, debug_str(mi->name), debug_str(mi->email));
        free(mi->name);
        free(mi->email);
 }
@@ -37,8 +40,11 @@ static void free_mailmap_info(void *p, const char *s)
 static void free_mailmap_entry(void *p, const char *s)
 {
        struct mailmap_entry *me = (struct mailmap_entry *)p;
-       debug_mm("mailmap: removing entries for <%s>, with %d sub-entries\n", s, me->namemap.nr);
-       debug_mm("mailmap: - simple: '%s' <%s>\n", me->name, me->email);
+       debug_mm("mailmap: removing entries for <%s>, with %d sub-entries\n",
+                s, me->namemap.nr);
+       debug_mm("mailmap: - simple: '%s' <%s>\n",
+                debug_str(me->name), debug_str(me->email));
+
        free(me->name);
        free(me->email);
 
@@ -47,7 +53,8 @@ static void free_mailmap_entry(void *p, const char *s)
 }
 
 static void add_mapping(struct string_list *map,
-                       char *new_name, char *new_email, char *old_name, char *old_email)
+                       char *new_name, char *new_email,
+                       char *old_name, char *old_email)
 {
        struct mailmap_entry *me;
        int index;
@@ -73,7 +80,8 @@ static void add_mapping(struct string_list *map,
        }
 
        if (old_name == NULL) {
-               debug_mm("mailmap: adding (simple) entry for %s at index %d\n", old_email, index);
+               debug_mm("mailmap: adding (simple) entry for %s at index %d\n",
+                        old_email, index);
                /* Replace current name and new email for simple entry */
                if (new_name) {
                        free(me->name);
@@ -85,7 +93,8 @@ static void add_mapping(struct string_list *map,
                }
        } else {
                struct mailmap_info *mi = xcalloc(1, sizeof(struct mailmap_info));
-               debug_mm("mailmap: adding (complex) entry for %s at index %d\n", old_email, index);
+               debug_mm("mailmap: adding (complex) entry for %s at index %d\n",
+                        old_email, index);
                if (new_name)
                        mi->name = xstrdup(new_name);
                if (new_email)
@@ -94,11 +103,12 @@ static void add_mapping(struct string_list *map,
        }
 
        debug_mm("mailmap:  '%s' <%s> -> '%s' <%s>\n",
-                old_name, old_email, new_name, new_email);
+                debug_str(old_name), old_email,
+                debug_str(new_name), debug_str(new_email));
 }
 
 static char *parse_name_and_email(char *buffer, char **name,
-               char **email, int allow_empty_email)
+                                 char **email, int allow_empty_email)
 {
        char *left, *right, *nstart, *nend;
        *name = *email = NULL;
@@ -183,20 +193,17 @@ static int read_mailmap_file(struct string_list *map, const char *filename,
        return 0;
 }
 
-static void read_mailmap_buf(struct string_list *map,
-                            const char *buf, unsigned long len,
-                            char **repo_abbrev)
+static void read_mailmap_string(struct string_list *map, char *buf,
+                               char **repo_abbrev)
 {
-       while (len) {
-               const char *end = strchrnul(buf, '\n');
-               unsigned long linelen = end - buf + 1;
-               char *line = xmemdupz(buf, linelen);
+       while (*buf) {
+               char *end = strchrnul(buf, '\n');
 
-               read_mailmap_line(map, line, repo_abbrev);
+               if (*end)
+                       *end++ = '\0';
 
-               free(line);
-               buf += linelen;
-               len -= linelen;
+               read_mailmap_line(map, buf, repo_abbrev);
+               buf = end;
        }
 }
 
@@ -220,7 +227,7 @@ static int read_mailmap_blob(struct string_list *map,
        if (type != OBJ_BLOB)
                return error("mailmap is not a blob: %s", name);
 
-       read_mailmap_buf(map, buf, size, repo_abbrev);
+       read_mailmap_string(map, buf, repo_abbrev);
 
        free(buf);
        return 0;
@@ -302,21 +309,25 @@ static struct string_list_item *lookup_prefix(struct string_list *map,
 }
 
 int map_user(struct string_list *map,
-                        const char **email, size_t *emaillen,
-                        const char **name, size_t *namelen)
+            const char **email, size_t *emaillen,
+            const char **name, size_t *namelen)
 {
        struct string_list_item *item;
        struct mailmap_entry *me;
 
        debug_mm("map_user: map '%.*s' <%.*s>\n",
-                (int)*namelen, *name, (int)*emaillen, *email);
+                (int)*namelen, debug_str(*name),
+                (int)*emaillen, debug_str(*email));
 
        item = lookup_prefix(map, *email, *emaillen);
        if (item != NULL) {
                me = (struct mailmap_entry *)item->util;
                if (me->namemap.nr) {
-                       /* The item has multiple items, so we'll look up on name too */
-                       /* If the name is not found, we choose the simple entry      */
+                       /*
+                        * The item has multiple items, so we'll look up on
+                        * name too. If the name is not found, we choose the
+                        * simple entry.
+                        */
                        struct string_list_item *subitem;
                        subitem = lookup_prefix(&me->namemap, *name, *namelen);
                        if (subitem)
@@ -337,8 +348,9 @@ int map_user(struct string_list *map,
                                *name = mi->name;
                                *namelen = strlen(*name);
                }
-               debug_mm("map_user:  to '%.*s' <%.*s>\n", (int)*namelen, *name,
-                                (int)*emaillen, *email);
+               debug_mm("map_user:  to '%.*s' <%.*s>\n",
+                        (int)*namelen, debug_str(*name),
+                        (int)*emaillen, debug_str(*email));
                return 1;
        }
        debug_mm("map_user:  --\n");