gfs2_block_map calls gfs2_meta_inode_buffer with &mp.mp_bh
as an argument. mp.mp_bh are filled with zero at the beginning
If gfs2_meta_inode_buffer returns non-zero value, gfs2_block_map
calls release_metapath to free buffers chained to mp.mp_bh.
release_metapath checks each slot of mp.mp_bh[i] and
free(with brelse) unless the slot is filled with NULL.
&mp.mp_bh passed to gfs2_meta_inode_buffer is filled at
gfs2_meta_read. gfs2_meta_read is filled a buffer allocated with
gfs2_getbuf even if EIO occurs. When EIO occurs, the allocated buffer
is brelse'ed though the pointer(wrong poiner) points the brelse'ed is
passed back to caller via an argument bhp.
gfs2_meta_indirect_buffer, the caller also pass the wrong pointer
to its caller with EIO. Finally gfs2_block_map gets both EIO and
&mp.mp_bh filled with the wrong pointer. release_metapath
calls brelse again on the wrong pointer.
Signed-off-by: Masatake YAMATO <firstname.lastname@example.org>
Signed-off-by: Steven Whitehouse <email@example.com>