tdb2: cleanup oob handling.
authorRusty Russell <rusty@rustcorp.com.au>
Wed, 31 Aug 2011 01:13:12 +0000 (10:43 +0930)
committerRusty Russell <rusty@rustcorp.com.au>
Wed, 31 Aug 2011 01:13:12 +0000 (10:43 +0930)
The tdb_oob() function can fail due to errors, as well as because the length
asked for is greater than the size of the file.  Clean that up:

(1) If probe is true, only fail if there's an error, not if the length is
    too great.
(2) Exit tdb_open() if it tdb_oob() probe fails; this helps cut down
    test time for failtest.
(3) Don't set probe to true in tdb_direct() fail; a minor issue, but it means
    we log failure.

ccan/tdb2/io.c
ccan/tdb2/open.c
ccan/tdb2/transaction.c

index 8c5f45f30827c9e722227e3787797288713e056e..4166cd4c67caf0475684fc03a0e9de86e714500e 100644 (file)
@@ -70,7 +70,9 @@ void tdb_mmap(struct tdb_context *tdb)
 /* check for an out of bounds access - if it is out of bounds then
    see if the database has been expanded by someone else and expand
    if necessary
-   note that "len" is the minimum length needed for the db
+   note that "len" is the minimum length needed for the db.
+
+   If probe is true, len being too large isn't a failure.
 */
 static enum TDB_ERROR tdb_oob(struct tdb_context *tdb, tdb_off_t len,
                              bool probe)
@@ -84,15 +86,16 @@ static enum TDB_ERROR tdb_oob(struct tdb_context *tdb, tdb_off_t len,
               || tdb_has_expansion_lock(tdb));
 
        if (len <= tdb->file->map_size)
-               return 0;
+               return TDB_SUCCESS;
        if (tdb->flags & TDB_INTERNAL) {
-               if (!probe) {
-                       tdb_logerr(tdb, TDB_ERR_IO, TDB_LOG_ERROR,
-                                "tdb_oob len %lld beyond internal"
-                                " malloc size %lld",
-                                (long long)len,
-                                (long long)tdb->file->map_size);
-               }
+               if (probe)
+                       return TDB_SUCCESS;
+
+               tdb_logerr(tdb, TDB_ERR_IO, TDB_LOG_ERROR,
+                          "tdb_oob len %lld beyond internal"
+                          " malloc size %lld",
+                          (long long)len,
+                          (long long)tdb->file->map_size);
                return TDB_ERR_IO;
        }
 
@@ -111,11 +114,12 @@ static enum TDB_ERROR tdb_oob(struct tdb_context *tdb, tdb_off_t len,
        tdb_unlock_expand(tdb, F_RDLCK);
 
        if (st.st_size < (size_t)len) {
-               if (!probe) {
-                       tdb_logerr(tdb, TDB_ERR_IO, TDB_LOG_ERROR,
-                                  "tdb_oob len %zu beyond eof at %zu",
-                                  (size_t)len, st.st_size);
-               }
+               if (probe)
+                       return TDB_SUCCESS;
+
+               tdb_logerr(tdb, TDB_ERR_IO, TDB_LOG_ERROR,
+                          "tdb_oob len %zu beyond eof at %zu",
+                          (size_t)len, st.st_size);
                return TDB_ERR_IO;
        }
 
@@ -242,7 +246,7 @@ static enum TDB_ERROR tdb_write(struct tdb_context *tdb, tdb_off_t off,
                                  "Write to read-only database");
        }
 
-       ecode = tdb->methods->oob(tdb, off + len, 0);
+       ecode = tdb->methods->oob(tdb, off + len, false);
        if (ecode != TDB_SUCCESS) {
                return ecode;
        }
@@ -272,7 +276,7 @@ static enum TDB_ERROR tdb_read(struct tdb_context *tdb, tdb_off_t off,
 {
        enum TDB_ERROR ecode;
 
-       ecode = tdb->methods->oob(tdb, off + len, 0);
+       ecode = tdb->methods->oob(tdb, off + len, false);
        if (ecode != TDB_SUCCESS) {
                return ecode;
        }
@@ -563,7 +567,7 @@ static void *tdb_direct(struct tdb_context *tdb, tdb_off_t off, size_t len,
        if (unlikely(!tdb->file->map_ptr))
                return NULL;
 
-       ecode = tdb_oob(tdb, off + len, true);
+       ecode = tdb_oob(tdb, off + len, false);
        if (unlikely(ecode != TDB_SUCCESS))
                return TDB_ERR_PTR(ecode);
        return (char *)tdb->file->map_ptr + off;
index daa83a334c44a39db4dad37c77e0090fee858769..fec3ef1596a562c90c6c40588265b0e05c93ed20 100644 (file)
@@ -561,7 +561,9 @@ struct tdb_context *tdb_open(const char *name, int tdb_flags,
        tdb_unlock_open(tdb, openlock);
 
        /* This make sure we have current map_size and mmap. */
-       tdb->methods->oob(tdb, tdb->file->map_size + 1, true);
+       ecode = tdb->methods->oob(tdb, tdb->file->map_size + 1, true);
+       if (unlikely(ecode != TDB_SUCCESS))
+               goto fail;
 
        /* Now it's fully formed, recover if necessary. */
        berr = tdb_needs_recovery(tdb);
index b13223bc2e18c7f82b6fdf4615adc69ca14bbffb..eda65c520842240e871ed3439378432f102a4d9c 100644 (file)
@@ -348,15 +348,14 @@ static void transaction_write_existing(struct tdb_context *tdb, tdb_off_t off,
 static enum TDB_ERROR transaction_oob(struct tdb_context *tdb, tdb_off_t len,
                                      bool probe)
 {
-       if (len <= tdb->file->map_size) {
+       if (len <= tdb->file->map_size || probe) {
                return TDB_SUCCESS;
        }
-       if (!probe) {
-               tdb_logerr(tdb, TDB_ERR_IO, TDB_LOG_ERROR,
-                          "tdb_oob len %lld beyond transaction size %lld",
-                          (long long)len,
-                          (long long)tdb->file->map_size);
-       }
+
+       tdb_logerr(tdb, TDB_ERR_IO, TDB_LOG_ERROR,
+                  "tdb_oob len %lld beyond transaction size %lld",
+                  (long long)len,
+                  (long long)tdb->file->map_size);
        return TDB_ERR_IO;
 }