2008-02-07 06:19:53

by David Teigland

[permalink] [raw]
Subject: [PATCH 08/16] dlm: verify that places expecting rcom_lock have packet long enough

From: Al Viro <[email protected]>

Signed-off-by: Al Viro <[email protected]>
Signed-off-by: David Teigland <[email protected]>
---
fs/dlm/lock.c | 3 +++
fs/dlm/rcom.c | 12 +++++++++++-
2 files changed, 14 insertions(+), 1 deletions(-)

diff --git a/fs/dlm/lock.c b/fs/dlm/lock.c
index 75176b5..6c605fc 100644
--- a/fs/dlm/lock.c
+++ b/fs/dlm/lock.c
@@ -4266,6 +4266,7 @@ static struct dlm_lkb *search_remid(struct dlm_rsb *r, int nodeid,
return NULL;
}

+/* needs at least dlm_rcom + rcom_lock */
static int receive_rcom_lock_args(struct dlm_ls *ls, struct dlm_lkb *lkb,
struct dlm_rsb *r, struct dlm_rcom *rc)
{
@@ -4315,6 +4316,7 @@ static int receive_rcom_lock_args(struct dlm_ls *ls, struct dlm_lkb *lkb,
the given values and send back our lkid. We send back our lkid by sending
back the rcom_lock struct we got but with the remid field filled in. */

+/* needs at least dlm_rcom + rcom_lock */
int dlm_recover_master_copy(struct dlm_ls *ls, struct dlm_rcom *rc)
{
struct rcom_lock *rl = (struct rcom_lock *) rc->rc_buf;
@@ -4370,6 +4372,7 @@ int dlm_recover_master_copy(struct dlm_ls *ls, struct dlm_rcom *rc)
return error;
}

+/* needs at least dlm_rcom + rcom_lock */
int dlm_recover_process_copy(struct dlm_ls *ls, struct dlm_rcom *rc)
{
struct rcom_lock *rl = (struct rcom_lock *) rc->rc_buf;
diff --git a/fs/dlm/rcom.c b/fs/dlm/rcom.c
index a312f1d..ef9d0f9 100644
--- a/fs/dlm/rcom.c
+++ b/fs/dlm/rcom.c
@@ -357,6 +357,7 @@ int dlm_send_rcom_lock(struct dlm_rsb *r, struct dlm_lkb *lkb)
return error;
}

+/* needs at least dlm_rcom + rcom_lock */
static void receive_rcom_lock(struct dlm_ls *ls, struct dlm_rcom *rc_in)
{
struct dlm_rcom *rc;
@@ -448,6 +449,8 @@ static int is_old_reply(struct dlm_ls *ls, struct dlm_rcom *rc)

void dlm_receive_rcom(struct dlm_ls *ls, struct dlm_rcom *rc, int nodeid)
{
+ int lock_size = sizeof(struct dlm_rcom) + sizeof(struct rcom_lock);
+
if (dlm_recovery_stopped(ls) && (rc->rc_type != DLM_RCOM_STATUS)) {
log_debug(ls, "ignoring recovery message %x from %d",
rc->rc_type, nodeid);
@@ -471,6 +474,8 @@ void dlm_receive_rcom(struct dlm_ls *ls, struct dlm_rcom *rc, int nodeid)
break;

case DLM_RCOM_LOCK:
+ if (rc->rc_header.h_length < lock_size)
+ goto Eshort;
receive_rcom_lock(ls, rc);
break;

@@ -487,13 +492,18 @@ void dlm_receive_rcom(struct dlm_ls *ls, struct dlm_rcom *rc, int nodeid)
break;

case DLM_RCOM_LOCK_REPLY:
+ if (rc->rc_header.h_length < lock_size)
+ goto Eshort;
dlm_recover_process_copy(ls, rc);
break;

default:
log_error(ls, "receive_rcom bad type %d", rc->rc_type);
}
- out:
+out:
return;
+Eshort:
+ log_error(ls, "recovery message %x from %d is too short",
+ rc->rc_type, nodeid);
}

--
1.5.3.3