The branch, v3-3-test has been updated
via c9df9c68da21610d9c32a57e24f45d36ebe432c5 (commit)
from 7434898b10a5c5780bd015b7bdca3eaa7a2b5475 (commit)
http://gitweb.samba.org/?p=samba.git;a=shortlog;h=v3-3-test
- Log -----------------------------------------------------------------
commit c9df9c68da21610d9c32a57e24f45d36ebe432c5
Author: Volker Lendecke <[email protected]>
Date: Sun May 24 18:57:13 2009 +0200
Fix a race condition in winbind leading to a panic
In winbind, we do multiple events in one select round. This needs fixing,
but
as long as we're still using it, for efficiency reasons we need to do that.
What can happen is the following: We have outgoing data pending for a
client,
thus
state->fd_event.flags == EVENT_FD_WRITE
Now a new client comes in, we go through the list of clients to find an idle
one. The detection for idle clients in remove_idle_client does not take the
pending data into account. We close the socket that has pending outgoing
data,
the accept(2) one syscall later gives us the same socket.
In new_connection(), we do a setup_async_read, setting up a read fde. The
select from before however had found the socket (that we had already
closed!!)
to be writable. In rw_callback we only want to see a readable flag, and we
panic in the SMB_ASSERT(flags == EVENT_FD_READ).
Found using
bin/smbtorture //127.0.0.1/tmp -U% -N 500 -o 2 local-wbclient
Volker
(commit 68c5c6df in master)
-----------------------------------------------------------------------
Summary of changes:
source/winbindd/winbindd.c | 1 +
1 files changed, 1 insertions(+), 0 deletions(-)
Changeset truncated at 500 lines:
diff --git a/source/winbindd/winbindd.c b/source/winbindd/winbindd.c
index f333e37..9005e67 100644
--- a/source/winbindd/winbindd.c
+++ b/source/winbindd/winbindd.c
@@ -778,6 +778,7 @@ static bool remove_idle_client(void)
for (state = winbindd_client_list(); state; state = state->next) {
if (state->response.result != WINBINDD_PENDING &&
+ state->fd_event.flags == EVENT_FD_READ &&
!state->getpwent_state && !state->getgrent_state) {
nidle++;
if (!last_access || state->last_access < last_access) {
--
Samba Shared Repository
