There is one signedness issue in tdb which prevents traverses of TDB records

over the 2G offset on systems which support 64 bit file offsets.  This fixes
that case.

On systems with 32 bit offsets, expansion and fcntl locking on these records
will fail anyway.  SAMBA already does '#define _FILE_OFFSET_BITS 64' in
config.h (on my 32-bit x86 Linux system at least) to get 64 bit file offsets.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>

1 files changed, 21 insertions, 9 deletions

diff --git a/lib/tdb/common/traverse.c b/lib/tdb/common/traverse.c
index 07b0c23858..8e5a63a5ec 100644
--- a/lib/tdb/common/traverse.c
+++ b/lib/tdb/common/traverse.c
@@ -27,8 +27,11 @@
 
 #include "tdb_private.h"
 
-/* Uses traverse lock: 0 = finish, -1 = error, other = record offset */
-static int tdb_next_lock(struct tdb_context *tdb, struct tdb_traverse_lock *tlock,
+#define TDB_NEXT_LOCK_ERR ((tdb_off_t)-1)
+
+/* Uses traverse lock: 0 = finish, TDB_NEXT_LOCK_ERR = error,
+   other = record offset */
+static tdb_off_t tdb_next_lock(struct tdb_context *tdb, struct tdb_traverse_lock *tlock,
 			 struct list_struct *rec)
 {
 	int want_next = (tlock->off != 0);
@@ -71,7 +74,7 @@ static int tdb_next_lock(struct tdb_context *tdb, struct tdb_traverse_lock *tloc
 		}
 
 		if (tdb_lock(tdb, tlock->hash, tlock->lock_rw) == -1)
-			return -1;
+			return TDB_NEXT_LOCK_ERR;
 
 		/* No previous record?  Start at top of chain. */
 		if (!tlock->off) {
@@ -99,6 +102,7 @@ static int tdb_next_lock(struct tdb_context *tdb, struct tdb_traverse_lock *tloc
 
 			/* Detect infinite loops. From "Shlomi Yaakobovich" <Shlomi@exanet.com>. */
 			if (tlock->off == rec->next) {
+				tdb->ecode = TDB_ERR_CORRUPT;
 				TDB_LOG((tdb, TDB_DEBUG_FATAL, "tdb_next_lock: loop detected.\n"));
 				goto fail;
 			}
@@ -127,7 +131,7 @@ static int tdb_next_lock(struct tdb_context *tdb, struct tdb_traverse_lock *tloc
 	tlock->off = 0;
 	if (tdb_unlock(tdb, tlock->hash, tlock->lock_rw) != 0)
 		TDB_LOG((tdb, TDB_DEBUG_FATAL, "tdb_next_lock: On error unlock failed!\n"));
-	return -1;
+	return TDB_NEXT_LOCK_ERR;
 }
 
 /* traverse the entire database - calling fn(tdb, key, data) on each element.
@@ -141,7 +145,8 @@ static int tdb_traverse_internal(struct tdb_context *tdb,
 {
 	TDB_DATA key, dbuf;
 	struct list_struct rec;
-	int ret, count = 0;
+	int ret = 0, count = 0;
+	tdb_off_t off;
 
 	/* This was in the initializaton, above, but the IRIX compiler
 	 * did not like it.  crh
@@ -152,7 +157,11 @@ static int tdb_traverse_internal(struct tdb_context *tdb,
 	tdb->travlocks.next = tl;
 
 	/* tdb_next_lock places locks on the record returned, and its chain */
-	while ((ret = tdb_next_lock(tdb, tl, &rec)) > 0) {
+	while ((off = tdb_next_lock(tdb, tl, &rec)) != 0) {
+		if (off == TDB_NEXT_LOCK_ERR) {
+			ret = -1;
+			goto out;
+		}
 		count++;
 		/* now read the full record */
 		key.dptr = tdb_alloc_read(tdb, tl->off + sizeof(rec), 
@@ -177,7 +186,6 @@ static int tdb_traverse_internal(struct tdb_context *tdb,
 		}
 		if (fn && fn(tdb, key, dbuf, private_data)) {
 			/* They want us to terminate traversal */
-			ret = count;
 			if (tdb_unlock_record(tdb, tl->off) != 0) {
 				TDB_LOG((tdb, TDB_DEBUG_FATAL, "tdb_traverse: unlock_record failed!\n"));;
 				ret = -1;
@@ -256,6 +264,7 @@ TDB_DATA tdb_firstkey(struct tdb_context *tdb)
 {
 	TDB_DATA key;
 	struct list_struct rec;
+	tdb_off_t off;
 
 	/* release any old lock */
 	if (tdb_unlock_record(tdb, tdb->travlocks.off) != 0)
@@ -264,7 +273,8 @@ TDB_DATA tdb_firstkey(struct tdb_context *tdb)
 	tdb->travlocks.lock_rw = F_RDLCK;
 
 	/* Grab first record: locks chain and returned record. */
-	if (tdb_next_lock(tdb, &tdb->travlocks, &rec) <= 0)
+ 	off = tdb_next_lock(tdb, &tdb->travlocks, &rec);
+ 	if (off == 0 || off == TDB_NEXT_LOCK_ERR)
 		return tdb_null;
 	/* now read the key */
 	key.dsize = rec.key_len;
@@ -283,6 +293,7 @@ TDB_DATA tdb_nextkey(struct tdb_context *tdb, TDB_DATA oldkey)
 	TDB_DATA key = tdb_null;
 	struct list_struct rec;
 	unsigned char *k = NULL;
+	tdb_off_t off;
 
 	/* Is locked key the old key?  If so, traverse will be reliable. */
 	if (tdb->travlocks.off) {
@@ -322,7 +333,8 @@ TDB_DATA tdb_nextkey(struct tdb_context *tdb, TDB_DATA oldkey)
 
 	/* Grab next record: locks chain and returned record,
 	   unlocks old record */
-	if (tdb_next_lock(tdb, &tdb->travlocks, &rec) > 0) {
+	off = tdb_next_lock(tdb, &tdb->travlocks, &rec);
+	if (off != TDB_NEXT_LOCK_ERR && off != 0) {
 		key.dsize = rec.key_len;
 		key.dptr = tdb_alloc_read(tdb, tdb->travlocks.off+sizeof(rec),
 					  key.dsize);