ocfs2: Check heartbeat mode for kernel stacks only

Commit 2c442719e90a44a6982c033d69df4aae4b167cfa added some checks for proper
heartbeat mode when the o2cb stack is running.  Unfortunately, it didn't
take into account that a userpsace stack could be running. Fix this by only
doing the check if o2cb is in use. This patch allows userspace stacks to
mount the fs again.

Cc: stable@kernel.org
Signed-off-by: Mark Fasheh <mfasheh@suse.com>
Signed-off-by: Joel Becker <jlbec@evilplan.org>

1 files changed, 20 insertions, 8 deletions

diff --git a/fs/ocfs2/super.c b/fs/ocfs2/super.c
index 38f986d2447e..36c423fb0635 100644
--- a/fs/ocfs2/super.c
+++ b/fs/ocfs2/super.c
@@ -1316,7 +1316,7 @@ static int ocfs2_parse_options(struct super_block *sb,
                                struct mount_options *mopt,
                                int is_remount)
 {
-        int status;
+        int status, user_stack = 0;
         char *p;
         u32 tmp;
 
@@ -1459,6 +1459,15 @@ static int ocfs2_parse_options(struct super_block *sb,
                         memcpy(mopt->cluster_stack, args[0].from,
                                OCFS2_STACK_LABEL_LEN);
                         mopt->cluster_stack[OCFS2_STACK_LABEL_LEN] = '\0';
+                        /*
+                         * Open code the memcmp here as we don't have
+                         * an osb to pass to
+                         * ocfs2_userspace_stack().
+                         */
+                        if (memcmp(mopt->cluster_stack,
+                                   OCFS2_CLASSIC_CLUSTER_STACK,
+                                   OCFS2_STACK_LABEL_LEN))
+                                user_stack = 1;
                         break;
                 case Opt_inode64:
                         mopt->mount_opt |= OCFS2_MOUNT_INODE64;
@@ -1514,13 +1523,16 @@ static int ocfs2_parse_options(struct super_block *sb,
                 }
         }
 
-        /* Ensure only one heartbeat mode */
-        tmp = mopt->mount_opt & (OCFS2_MOUNT_HB_LOCAL | OCFS2_MOUNT_HB_GLOBAL |
-                                 OCFS2_MOUNT_HB_NONE);
-        if (hweight32(tmp) != 1) {
-                mlog(ML_ERROR, "Invalid heartbeat mount options\n");
-                status = 0;
-                goto bail;
+        if (user_stack == 0) {
+                /* Ensure only one heartbeat mode */
+                tmp = mopt->mount_opt & (OCFS2_MOUNT_HB_LOCAL |
+                                         OCFS2_MOUNT_HB_GLOBAL |
+                                         OCFS2_MOUNT_HB_NONE);
+                if (hweight32(tmp) != 1) {
+                        mlog(ML_ERROR, "Invalid heartbeat mount options\n");
+                        status = 0;
+                        goto bail;
+                }
         }
 
         status = 1;