6 files changed, 24 insertions, 14 deletions

diff --git a/lib/ntdb/check.c b/lib/ntdb/check.c
index 723e7b11bf..be27003a51 100644
--- a/lib/ntdb/check.c
+++ b/lib/ntdb/check.c
@@ -505,10 +505,9 @@ static enum NTDB_ERROR check_free(struct ntdb_context *ntdb,
 
 	}
 
-	ecode = ntdb->io->oob(ntdb, off,
-			     frec_len(frec)
-			     + sizeof(struct ntdb_used_record),
-			     false);
+	ecode = ntdb_oob(ntdb, off,
+			 frec_len(frec) + sizeof(struct ntdb_used_record),
+			 false);
 	if (ecode != NTDB_SUCCESS) {
 		return ecode;
 	}
diff --git a/lib/ntdb/free.c b/lib/ntdb/free.c
index f51aa5bc33..3e31937382 100644
--- a/lib/ntdb/free.c
+++ b/lib/ntdb/free.c
@@ -932,7 +932,7 @@ static enum NTDB_ERROR ntdb_expand(struct ntdb_context *ntdb, ntdb_len_t size)
 
 	/* Someone else may have expanded the file, so retry. */
 	old_size = ntdb->file->map_size;
-	ntdb->io->oob(ntdb, ntdb->file->map_size, 1, true);
+	ntdb_oob(ntdb, ntdb->file->map_size, 1, true);
 	if (ntdb->file->map_size != old_size) {
 		ntdb_unlock_expand(ntdb, F_WRLCK);
 		return NTDB_SUCCESS;
diff --git a/lib/ntdb/io.c b/lib/ntdb/io.c
index b20141cc8f..138a405dda 100644
--- a/lib/ntdb/io.c
+++ b/lib/ntdb/io.c
@@ -92,8 +92,9 @@ enum NTDB_ERROR ntdb_mmap(struct ntdb_context *ntdb)
 
    If probe is true, len being too large isn't a failure.
 */
-static enum NTDB_ERROR ntdb_oob(struct ntdb_context *ntdb,
-			      ntdb_off_t off, ntdb_len_t len, bool probe)
+static enum NTDB_ERROR ntdb_normal_oob(struct ntdb_context *ntdb,
+				       ntdb_off_t off, ntdb_len_t len,
+				       bool probe)
 {
 	struct stat st;
 	enum NTDB_ERROR ecode;
@@ -112,8 +113,6 @@ static enum NTDB_ERROR ntdb_oob(struct ntdb_context *ntdb,
 				  (long long)off, (long long)len);
 	}
 
-	if (len + off <= ntdb->file->map_size)
-		return NTDB_SUCCESS;
 	if (ntdb->flags & NTDB_INTERNAL) {
 		if (probe)
 			return NTDB_SUCCESS;
@@ -271,7 +270,7 @@ static enum NTDB_ERROR ntdb_write(struct ntdb_context *ntdb, ntdb_off_t off,
 				  "Write to read-only database");
 	}
 
-	ecode = ntdb->io->oob(ntdb, off, len, false);
+	ecode = ntdb_oob(ntdb, off, len, false);
 	if (ecode != NTDB_SUCCESS) {
 		return ecode;
 	}
@@ -305,7 +304,7 @@ static enum NTDB_ERROR ntdb_read(struct ntdb_context *ntdb, ntdb_off_t off,
 {
 	enum NTDB_ERROR ecode;
 
-	ecode = ntdb->io->oob(ntdb, off, len, false);
+	ecode = ntdb_oob(ntdb, off, len, false);
 	if (ecode != NTDB_SUCCESS) {
 		return ecode;
 	}
@@ -639,7 +638,7 @@ void ntdb_inc_seqnum(struct ntdb_context *ntdb)
 static const struct ntdb_methods io_methods = {
 	ntdb_read,
 	ntdb_write,
-	ntdb_oob,
+	ntdb_normal_oob,
 	ntdb_expand_file,
 	ntdb_direct,
 };
diff --git a/lib/ntdb/open.c b/lib/ntdb/open.c
index dc473d2680..6aac46ab2f 100644
--- a/lib/ntdb/open.c
+++ b/lib/ntdb/open.c
@@ -718,7 +718,7 @@ _PUBLIC_ struct ntdb_context *ntdb_open(const char *name, int ntdb_flags,
 	ntdb_unlock_open(ntdb, openlock);
 
 	/* This makes sure we have current map_size and mmap. */
-	ecode = ntdb->io->oob(ntdb, ntdb->file->map_size, 1, true);
+	ecode = ntdb_oob(ntdb, ntdb->file->map_size, 1, true);
 	if (unlikely(ecode != NTDB_SUCCESS))
 		goto fail;
 
diff --git a/lib/ntdb/private.h b/lib/ntdb/private.h
index ee8eeb76af..f46b5ef906 100644
--- a/lib/ntdb/private.h
+++ b/lib/ntdb/private.h
@@ -630,6 +630,18 @@ enum NTDB_ERROR COLD PRINTF_FMT(4, 5)
 		    enum ntdb_log_level level,
 		    const char *fmt, ...);
 
+static inline enum NTDB_ERROR ntdb_oob(struct ntdb_context *ntdb,
+				       ntdb_off_t off, ntdb_len_t len,
+				       bool probe)
+{
+	if (likely(off + len >= off)
+	    && likely(off + len <= ntdb->file->map_size)
+	    && likely(!probe)) {
+		    return NTDB_SUCCESS;
+	}
+	return ntdb->io->oob(ntdb, off, len, probe);
+}
+
 #ifdef NTDB_TRACE
 void ntdb_trace(struct ntdb_context *ntdb, const char *op);
 void ntdb_trace_seqnum(struct ntdb_context *ntdb, uint32_t seqnum, const char *op);
diff --git a/lib/ntdb/transaction.c b/lib/ntdb/transaction.c
index 11dd7b4af5..a265252174 100644
--- a/lib/ntdb/transaction.c
+++ b/lib/ntdb/transaction.c
@@ -568,7 +568,7 @@ _PUBLIC_ enum NTDB_ERROR ntdb_transaction_start(struct ntdb_context *ntdb)
 
 	/* make sure we know about any file expansions already done by
 	   anyone else */
-	ntdb->io->oob(ntdb, ntdb->file->map_size, 1, true);
+	ntdb_oob(ntdb, ntdb->file->map_size, 1, true);
 	ntdb->transaction->old_map_size = ntdb->file->map_size;
 
 	/* finally hook the io methods, replacing them with