ext4: Fix memory leak of journal buffer if block is updated multiple times
If the same block is updated multiple times in a row during a single
file system operation, gd_index is decremented to use the same journal
entry again. Avoid loosing the already allocated buffer.
Signed-off-by: Stefan Brüns <stefan.bruens@rwth-aachen.de>
diff --git a/fs/ext4/ext4_journal.c b/fs/ext4/ext4_journal.c
index cf14049..5a25be4 100644
--- a/fs/ext4/ext4_journal.c
+++ b/fs/ext4/ext4_journal.c
@@ -190,7 +190,11 @@
printf("Invalid input arguments %s\n", __func__);
return -EINVAL;
}
- dirty_block_ptr[gd_index]->buf = zalloc(fs->blksz);
+ if (dirty_block_ptr[gd_index]->buf)
+ assert(dirty_block_ptr[gd_index]->blknr == blknr);
+ else
+ dirty_block_ptr[gd_index]->buf = zalloc(fs->blksz);
+
if (!dirty_block_ptr[gd_index]->buf)
return -ENOMEM;
memcpy(dirty_block_ptr[gd_index]->buf, metadata_buffer, fs->blksz);