The branch, master has been updated
via a752bbd... s3:registry: eliminate race condition in
creating/scanning sorted subkeys
from 09f3ed1... s3:make "net conf addshare" atomic by wrapping all
writes in one transaction
http://gitweb.samba.org/?p=samba.git;a=shortlog;h=master
- Log -----------------------------------------------------------------
commit a752bbd10d661ebc93b8d51bd583eb62eb00ad18
Author: Michael Adam <[email protected]>
Date: Mon Feb 8 11:01:47 2010 +0100
s3:registry: eliminate race condition in creating/scanning sorted subkeys
Called, from key_exists, scan_sorted_subkeys re-creates the sorted
subkeys record of the given key and then searches through it.
The race is that between creation and parsing of the sorted subkey
record, another process that stores some other subkey of the same
parent key will delete the sorted subkey record, resulting in an
WERR_BADFILE of an operation that should actually succeed.
This patch fixes the issue by wrapping the creation and parsing
into a transaction.
Michael
-----------------------------------------------------------------------
Summary of changes:
source3/registry/reg_backend_db.c | 17 +++++++++++++++++
1 files changed, 17 insertions(+), 0 deletions(-)
Changeset truncated at 500 lines:
diff --git a/source3/registry/reg_backend_db.c
b/source3/registry/reg_backend_db.c
index 43963db..fe15b4e 100644
--- a/source3/registry/reg_backend_db.c
+++ b/source3/registry/reg_backend_db.c
@@ -1368,14 +1368,31 @@ static bool scan_parent_subkeys(struct db_context *db,
const char *parent,
if (state.scanned) {
result = state.found;
} else {
+ res = db->transaction_start(db);
+ if (res != 0) {
+ DEBUG(0, ("error starting transacion\n"));
+ goto fail;
+ }
+
if (!create_sorted_subkeys(path, key)) {
+ res = db->transaction_cancel(db);
+ if (res != 0) {
+ smb_panic("Failed to cancel transaction.");
+ }
goto fail;
}
+
res = db->parse_record(db, string_term_tdb_data(key),
parent_subkey_scanner, &state);
if ((res == 0) && (state.scanned)) {
result = state.found;
}
+
+ res = db->transaction_commit(db);
+ if (res != 0) {
+ DEBUG(0, ("error committing transaction\n"));
+ result = false;
+ }
}
fail:
--
Samba Shared Repository
