dlm: dlm_process_incoming_buffer() fixes
* check that length is large enough to cover the non-variable part of message or
rcom resp. (after checking that it's large enough to cover the header, of
course).
* kill more pointless casts
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: David Teigland <teigland@redhat.com>
diff --git a/fs/dlm/dlm_internal.h b/fs/dlm/dlm_internal.h
index ec61bba..65499ce 100644
--- a/fs/dlm/dlm_internal.h
+++ b/fs/dlm/dlm_internal.h
@@ -403,6 +403,12 @@
char rc_buf[0];
};
+union dlm_packet {
+ struct dlm_header header; /* common to other two */
+ struct dlm_message message;
+ struct dlm_rcom rcom;
+};
+
struct rcom_config {
uint32_t rf_lvblen;
uint32_t rf_lsflags;
diff --git a/fs/dlm/lock.c b/fs/dlm/lock.c
index d9f07a4..2a28048 100644
--- a/fs/dlm/lock.c
+++ b/fs/dlm/lock.c
@@ -3822,21 +3822,20 @@
standard locking activity) or an RCOM (recovery message sent as part of
lockspace recovery). */
-void dlm_receive_buffer(struct dlm_header *hd, int nodeid)
+void dlm_receive_buffer(union dlm_packet *p, int nodeid)
{
- struct dlm_message *ms = (struct dlm_message *) hd;
- struct dlm_rcom *rc = (struct dlm_rcom *) hd;
+ struct dlm_header *hd = &p->header;
struct dlm_ls *ls;
int type = 0;
switch (hd->h_cmd) {
case DLM_MSG:
- dlm_message_in(ms);
- type = ms->m_type;
+ dlm_message_in(&p->message);
+ type = p->message.m_type;
break;
case DLM_RCOM:
- dlm_rcom_in(rc);
- type = rc->rc_type;
+ dlm_rcom_in(&p->rcom);
+ type = p->rcom.rc_type;
break;
default:
log_print("invalid h_cmd %d from %u", hd->h_cmd, nodeid);
@@ -3856,7 +3855,7 @@
hd->h_lockspace, nodeid, hd->h_cmd, type);
if (hd->h_cmd == DLM_RCOM && type == DLM_RCOM_STATUS)
- dlm_send_ls_not_ready(nodeid, rc);
+ dlm_send_ls_not_ready(nodeid, &p->rcom);
return;
}
@@ -3865,9 +3864,9 @@
down_read(&ls->ls_recv_active);
if (hd->h_cmd == DLM_MSG)
- dlm_receive_message(ls, ms, nodeid);
+ dlm_receive_message(ls, &p->message, nodeid);
else
- dlm_receive_rcom(ls, rc, nodeid);
+ dlm_receive_rcom(ls, &p->rcom, nodeid);
up_read(&ls->ls_recv_active);
dlm_put_lockspace(ls);
diff --git a/fs/dlm/lock.h b/fs/dlm/lock.h
index 27b6ed3..05d9c82 100644
--- a/fs/dlm/lock.h
+++ b/fs/dlm/lock.h
@@ -17,7 +17,7 @@
void dlm_dump_rsb(struct dlm_rsb *r);
void dlm_print_lkb(struct dlm_lkb *lkb);
void dlm_receive_message_saved(struct dlm_ls *ls, struct dlm_message *ms);
-void dlm_receive_buffer(struct dlm_header *hd, int nodeid);
+void dlm_receive_buffer(union dlm_packet *p, int nodeid);
int dlm_modes_compat(int mode1, int mode2);
void dlm_put_rsb(struct dlm_rsb *r);
void dlm_hold_rsb(struct dlm_rsb *r);
diff --git a/fs/dlm/midcomms.c b/fs/dlm/midcomms.c
index e69926e..07ac709 100644
--- a/fs/dlm/midcomms.c
+++ b/fs/dlm/midcomms.c
@@ -61,9 +61,9 @@
union {
unsigned char __buf[DLM_INBUF_LEN];
/* this is to force proper alignment on some arches */
- struct dlm_header dlm;
+ union dlm_packet p;
} __tmp;
- struct dlm_header *msg = &__tmp.dlm;
+ union dlm_packet *p = &__tmp.p;
int ret = 0;
int err = 0;
uint16_t msglen;
@@ -75,15 +75,22 @@
message may wrap around the end of the buffer back to the
start, so we need to use a temp buffer and copy_from_cb. */
- copy_from_cb(msg, base, offset, sizeof(struct dlm_header),
+ copy_from_cb(p, base, offset, sizeof(struct dlm_header),
limit);
- msglen = le16_to_cpu(msg->h_length);
- lockspace = msg->h_lockspace;
+ msglen = le16_to_cpu(p->header.h_length);
+ lockspace = p->header.h_lockspace;
err = -EINVAL;
if (msglen < sizeof(struct dlm_header))
break;
+ if (p->header.h_cmd == DLM_MSG) {
+ if (msglen < sizeof(struct dlm_message))
+ break;
+ } else {
+ if (msglen < sizeof(struct dlm_rcom))
+ break;
+ }
err = -E2BIG;
if (msglen > dlm_config.ci_buffer_size) {
log_print("message size %d from %d too big, buf len %d",
@@ -104,26 +111,26 @@
in the buffer on the stack (which should work for most
ordinary messages). */
- if (msglen > DLM_INBUF_LEN && msg == &__tmp.dlm) {
- msg = kmalloc(dlm_config.ci_buffer_size, GFP_KERNEL);
- if (msg == NULL)
+ if (msglen > sizeof(__tmp) && p == &__tmp.p) {
+ p = kmalloc(dlm_config.ci_buffer_size, GFP_KERNEL);
+ if (p == NULL)
return ret;
}
- copy_from_cb(msg, base, offset, msglen, limit);
+ copy_from_cb(p, base, offset, msglen, limit);
- BUG_ON(lockspace != msg->h_lockspace);
+ BUG_ON(lockspace != p->header.h_lockspace);
ret += msglen;
offset += msglen;
offset &= (limit - 1);
len -= msglen;
- dlm_receive_buffer(msg, nodeid);
+ dlm_receive_buffer(p, nodeid);
}
- if (msg != &__tmp.dlm)
- kfree(msg);
+ if (p != &__tmp.p)
+ kfree(p);
return err ? err : ret;
}