ocfs2: Fix endian bug in o2dlm protocol negotiation.
struct dlm_query_join_packet is made up of four one-byte fields. They
are effectively in big-endian order already. However, little-endian
machines swap them before putting the packet on the wire (because
query_join's response is a status, and that status is treated as a u32
on the wire). Thus, a big-endian and little-endian machines will
treat this structure differently.
The solution is to have little-endian machines swap the structure when
converting from the structure to the u32 representation.
Signed-off-by: Joel Becker <joel.becker@oracle.com>
Signed-off-by: Mark Fasheh <mark.fasheh@oracle.com>
diff --git a/fs/ocfs2/dlm/dlmcommon.h b/fs/ocfs2/dlm/dlmcommon.h
index 9843ee1..1f93963 100644
--- a/fs/ocfs2/dlm/dlmcommon.h
+++ b/fs/ocfs2/dlm/dlmcommon.h
@@ -602,17 +602,19 @@
JOIN_PROTOCOL_MISMATCH,
};
+struct dlm_query_join_packet {
+ u8 code; /* Response code. dlm_minor and fs_minor
+ are only valid if this is JOIN_OK */
+ u8 dlm_minor; /* The minor version of the protocol the
+ dlm is speaking. */
+ u8 fs_minor; /* The minor version of the protocol the
+ filesystem is speaking. */
+ u8 reserved;
+};
+
union dlm_query_join_response {
u32 intval;
- struct {
- u8 code; /* Response code. dlm_minor and fs_minor
- are only valid if this is JOIN_OK */
- u8 dlm_minor; /* The minor version of the protocol the
- dlm is speaking. */
- u8 fs_minor; /* The minor version of the protocol the
- filesystem is speaking. */
- u8 reserved;
- } packet;
+ struct dlm_query_join_packet packet;
};
struct dlm_lock_request
