From: Dmitriy Monakhov <dmonakhov@openvz.org>

sb_read may return NULL, let's explicitly check it.

Signed-off-by: Dmitriy Monakhov <dmonakhov@openvz.org>
Cc: Jan Kara <jack@ucw.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 fs/udf/super.c |    2 ++
 1 file changed, 2 insertions(+)

diff -puN fs/udf/super.c~udf-possible-null-pointer-dereference-while-load_partition fs/udf/super.c
--- a/fs/udf/super.c~udf-possible-null-pointer-dereference-while-load_partition
+++ a/fs/udf/super.c
@@ -1405,6 +1405,8 @@ udf_load_partition(struct super_block *s
 
 					pos = udf_block_map(UDF_SB_VAT(sb), 0);
 					bh = sb_bread(sb, pos);
+					if (!bh)
+						return 1;
 					UDF_SB_TYPEVIRT(sb,i).s_start_offset =
 						le16_to_cpu(((struct virtualAllocationTable20 *)bh->b_data + udf_ext0_offset(UDF_SB_VAT(sb)))->lengthHeader) +
 							udf_ext0_offset(UDF_SB_VAT(sb));
_