diff options
| -rw-r--r-- | lib/ChangeLog | 9 | ||||
| -rw-r--r-- | lib/log.c | 29 | ||||
| -rw-r--r-- | lib/log.h | 6 |
3 files changed, 34 insertions, 10 deletions
diff --git a/lib/ChangeLog b/lib/ChangeLog index 613a6fcb..da0fa8ca 100644 --- a/lib/ChangeLog +++ b/lib/ChangeLog @@ -1,5 +1,14 @@ 2008-02-28 Paul Jakma <paul.jakma@sun.com> + * log.c: (mes_lookup) Sowmini Varadhan diagnosed a problem where + this function can cause a NULL dereference, on lookups for unknown + indices, or messages with NULL strings. Can occur, e.g., debug + logging code when processing received messages. Fixed to accept a + pointer to a default string to be used if there is no match. + * log.h: LOOKUP adjusted to match + +2008-02-28 Paul Jakma <paul.jakma@sun.com> + * linklist.c: This implementation expects that the data pointer not be null, e.g. listgetdata() asserts this. The list add methods don't apply the same sanity check. @@ -752,14 +752,24 @@ lookup (struct message *mes, int key) } /* Older/faster version of message lookup function, but requires caller to pass - in the array size (instead of relying on a 0 key to terminate the search). */ + * in the array size (instead of relying on a 0 key to terminate the search). + * + * The return value is the message string if found, or the 'none' pointer + * provided otherwise. + */ const char * -mes_lookup (struct message *meslist, int max, int index) +mes_lookup (struct message *meslist, int max, int index, const char *none) { + int pos = index - meslist[0].key; + /* first check for best case: index is in range and matches the key - value in that slot */ - if ((index >= 0) && (index < max) && (meslist[index].key == index)) - return meslist[index].str; + * value in that slot. + * NB: key numbering might be offset from 0. E.g. protocol constants + * often start at 1. + */ + if ((pos >= 0) && (pos < max) + && (meslist[pos].key == index)) + return meslist[pos].str; /* fall back to linear search */ { @@ -769,14 +779,17 @@ mes_lookup (struct message *meslist, int max, int index) { if (meslist->key == index) { + const char *str = (meslist->str ? meslist->str : none); + zlog_debug ("message index %d [%s] found in position %d (max is %d)", - index, meslist->str, i, max); - return meslist->str; + index, str, i, max); + return str; } } } zlog_err("message index %d not found (max is %d)", index, max); - return NULL; + assert (none); + return none; } /* Wrapper around strerror to handle case where it returns NULL. */ @@ -142,10 +142,12 @@ extern int zlog_reset_file (struct zlog *zl); extern int zlog_rotate (struct zlog *); /* For hackey massage lookup and check */ -#define LOOKUP(x, y) mes_lookup(x, x ## _max, y) +#define LOOKUP(x, y) mes_lookup(x, x ## _max, y, "(no item found)") extern const char *lookup (struct message *, int); -extern const char *mes_lookup (struct message *meslist, int max, int index); +extern const char *mes_lookup (struct message *meslist, + int max, int index, + const char *no_item); extern const char *zlog_priority[]; extern const char *zlog_proto_names[]; |