1 files changed, 17 insertions, 9 deletions

diff --git a/fs/jbd/journal.c b/fs/jbd/journal.c
index 737f7246a4b5..f96f85092d1c 100644
--- a/fs/jbd/journal.c
+++ b/fs/jbd/journal.c
@@ -287,6 +287,7 @@ int journal_write_metadata_buffer(transaction_t *transaction,
         struct page *new_page;
         unsigned int new_offset;
         struct buffer_head *bh_in = jh2bh(jh_in);
+        journal_t *journal = transaction->t_journal;
 
         /*
          * The buffer really shouldn't be locked: only the current committing
@@ -300,6 +301,11 @@ int journal_write_metadata_buffer(transaction_t *transaction,
         J_ASSERT_BH(bh_in, buffer_jbddirty(bh_in));
 
         new_bh = alloc_buffer_head(GFP_NOFS|__GFP_NOFAIL);
+        /* keep subsequent assertions sane */
+        new_bh->b_state = 0;
+        init_buffer(new_bh, NULL, NULL);
+        atomic_set(&new_bh->b_count, 1);
+        new_jh = journal_add_journal_head(new_bh);      /* This sleeps */
 
         /*
          * If a new transaction has already done a buffer copy-out, then
@@ -361,14 +367,6 @@ repeat:
                 kunmap_atomic(mapped_data, KM_USER0);
         }
 
-        /* keep subsequent assertions sane */
-        new_bh->b_state = 0;
-        init_buffer(new_bh, NULL, NULL);
-        atomic_set(&new_bh->b_count, 1);
-        jbd_unlock_bh_state(bh_in);
-
-        new_jh = journal_add_journal_head(new_bh);      /* This sleeps */
-
         set_bh_page(new_bh, new_page, new_offset);
         new_jh->b_transaction = NULL;
         new_bh->b_size = jh2bh(jh_in)->b_size;
@@ -385,7 +383,11 @@ repeat:
          * copying is moved to the transaction's shadow queue.
          */
         JBUFFER_TRACE(jh_in, "file as BJ_Shadow");
-        journal_file_buffer(jh_in, transaction, BJ_Shadow);
+        spin_lock(&journal->j_list_lock);
+        __journal_file_buffer(jh_in, transaction, BJ_Shadow);
+        spin_unlock(&journal->j_list_lock);
+        jbd_unlock_bh_state(bh_in);
+
         JBUFFER_TRACE(new_jh, "file as BJ_IO");
         journal_file_buffer(new_jh, transaction, BJ_IO);
 
@@ -848,6 +850,12 @@ static int journal_reset(journal_t *journal)
 
         first = be32_to_cpu(sb->s_first);
         last = be32_to_cpu(sb->s_maxlen);
+        if (first + JFS_MIN_JOURNAL_BLOCKS > last + 1) {
+                printk(KERN_ERR "JBD: Journal too short (blocks %lu-%lu).\n",
+                       first, last);
+                journal_fail_superblock(journal);
+                return -EINVAL;
+        }
 
         journal->j_first = first;
         journal->j_last = last;