The branch, master has been updated
via b37b452... tdb: fix recovery reuse after crash
via 6269cdc... tdb: give a name to the invalid recovery area constant
(0)
from f299fe5... s4:provision Just 'do the right thing' with empty
smb.conf files
http://gitweb.samba.org/?p=samba.git;a=shortlog;h=master
- Log -----------------------------------------------------------------
commit b37b452cb8c1f56b37b04abe7bffdede371ca361
Author: Rusty Russell <ru...@rustcorp.com.au>
Date: Thu Feb 4 23:59:54 2010 +1030
tdb: fix recovery reuse after crash
If a process (or the machine) dies after just after writing the
recovery head (pointing at the end of file), the recovery record will filled
with 0x42. This will not invoke a recovery on open, since rec.magic
!= TDB_RECOVERY_MAGIC.
Unfortunately, the first transaction commit will happily reuse that
area: tdb_recovery_allocate() doesn't check the magic. The recovery
record has length 0x42424242, and it writes that back into the
now-valid-looking transaction header) for the next comer (which
happens to be tdb_wipe_all in my tests).
Signed-off-by: Rusty Russell <ru...@rustcorp.com.au>
commit 6269cdcd1538e2e3cead9e0f3c156b0363d607a0
Author: Rusty Russell <ru...@rustcorp.com.au>
Date: Fri Feb 5 00:00:24 2010 +1030
tdb: give a name to the invalid recovery area constant (0)
Signed-off-by: Rusty Russell <ru...@rustcorp.com.au>
-----------------------------------------------------------------------
Summary of changes:
lib/tdb/common/check.c | 2 +-
lib/tdb/common/tdb_private.h | 1 +
lib/tdb/common/transaction.c | 20 +++++++++++++-------
3 files changed, 15 insertions(+), 8 deletions(-)
Changeset truncated at 500 lines:
diff --git a/lib/tdb/common/check.c b/lib/tdb/common/check.c
index f0a15f8..6bbfd7d 100644
--- a/lib/tdb/common/check.c
+++ b/lib/tdb/common/check.c
@@ -370,7 +370,7 @@ int tdb_check(struct tdb_context *tdb,
goto free;
break;
case TDB_RECOVERY_MAGIC:
- case 0: /* Used for invalid (or in-progress) recovery area. */
+ case TDB_RECOVERY_INVALID_MAGIC:
if (recovery_start != off) {
TDB_LOG((tdb, TDB_DEBUG_ERROR,
"Unexpected recovery record at offset
%d\n",
diff --git a/lib/tdb/common/tdb_private.h b/lib/tdb/common/tdb_private.h
index be9be72..0e74b10 100644
--- a/lib/tdb/common/tdb_private.h
+++ b/lib/tdb/common/tdb_private.h
@@ -49,6 +49,7 @@ typedef uint32_t tdb_off_t;
#define TDB_FREE_MAGIC (~TDB_MAGIC)
#define TDB_DEAD_MAGIC (0xFEE1DEAD)
#define TDB_RECOVERY_MAGIC (0xf53bc0e7U)
+#define TDB_RECOVERY_INVALID_MAGIC (0x0)
#define TDB_ALIGNMENT 4
#define DEFAULT_HASH_SIZE 131
#define FREELIST_TOP (sizeof(struct tdb_header))
diff --git a/lib/tdb/common/transaction.c b/lib/tdb/common/transaction.c
index b8988ea..67104ef 100644
--- a/lib/tdb/common/transaction.c
+++ b/lib/tdb/common/transaction.c
@@ -596,10 +596,10 @@ int _tdb_transaction_cancel(struct tdb_context *tdb)
if (tdb->transaction->magic_offset) {
const struct tdb_methods *methods =
tdb->transaction->io_methods;
- uint32_t zero = 0;
+ uint32_t invalid = TDB_RECOVERY_INVALID_MAGIC;
/* remove the recovery marker */
- if (methods->tdb_write(tdb, tdb->transaction->magic_offset,
&zero, 4) == -1 ||
+ if (methods->tdb_write(tdb, tdb->transaction->magic_offset,
&invalid, 4) == -1 ||
transaction_sync(tdb, tdb->transaction->magic_offset, 4) == -1)
{
TDB_LOG((tdb, TDB_DEBUG_FATAL, "tdb_transaction_cancel:
failed to remove recovery magic\n"));
ret = -1;
@@ -695,10 +695,16 @@ static int tdb_recovery_allocate(struct tdb_context *tdb,
rec.rec_len = 0;
- if (recovery_head != 0 &&
- methods->tdb_read(tdb, recovery_head, &rec, sizeof(rec), DOCONV())
== -1) {
- TDB_LOG((tdb, TDB_DEBUG_FATAL, "tdb_recovery_allocate: failed
to read recovery record\n"));
- return -1;
+ if (recovery_head != 0) {
+ if (methods->tdb_read(tdb, recovery_head, &rec, sizeof(rec),
DOCONV()) == -1) {
+ TDB_LOG((tdb, TDB_DEBUG_FATAL, "tdb_recovery_allocate:
failed to read recovery record\n"));
+ return -1;
+ }
+ /* ignore invalid recovery regions: can happen in crash */
+ if (rec.magic != TDB_RECOVERY_MAGIC &&
+ rec.magic != TDB_RECOVERY_INVALID_MAGIC) {
+ recovery_head = 0;
+ }
}
*recovery_size = tdb_recovery_size(tdb);
@@ -793,7 +799,7 @@ static int transaction_setup_recovery(struct tdb_context
*tdb,
rec = (struct tdb_record *)data;
memset(rec, 0, sizeof(*rec));
- rec->magic = 0;
+ rec->magic = TDB_RECOVERY_INVALID_MAGIC;
rec->data_len = recovery_size;
rec->rec_len = recovery_max_size;
rec->key_len = old_map_size;
--
Samba Shared Repository
