Verify that number of partition maps isn't insanely high which can lead
to large allocation in udf_sb_alloc_partition_maps(). All partition maps
have to fit in the LVD which is in a single block.
Reported-by: syzbot+478f2c1a6f0f447a46bb@xxxxxxxxxxxxxxxxxxxxxxxxx
Signed-off-by: Jan Kara <jack@xxxxxxx>
---
fs/udf/super.c | 13 +++++++++++--
1 file changed, 11 insertions(+), 2 deletions(-)
I plan to merge this patch through my tree.
diff --git a/fs/udf/super.c b/fs/udf/super.c
index 1c8a736b3309..b2f168b0a0d1 100644
--- a/fs/udf/super.c
+++ b/fs/udf/super.c
@@ -1440,7 +1440,7 @@ static int udf_load_logicalvol(struct super_block *sb, sector_t block,
struct genericPartitionMap *gpm;
uint16_t ident;
struct buffer_head *bh;
- unsigned int table_len;
+ unsigned int table_len, part_map_count;
int ret;
bh = udf_read_tagged(sb, block, block, &ident);
@@ -1461,7 +1461,16 @@ static int udf_load_logicalvol(struct super_block *sb, sector_t block,
"logical volume");
if (ret)
goto out_bh;
- ret = udf_sb_alloc_partition_maps(sb, le32_to_cpu(lvd->numPartitionMaps));
+
+ part_map_count = le32_to_cpu(lvd->numPartitionMaps);
+ if (part_map_count > table_len / sizeof(struct genericPartitionMap1)) {
+ udf_err(sb, "error loading logical volume descriptor: "
+ "Too many partition maps (%u > %u)\n", part_map_count,
+ table_len / (unsigned)sizeof(struct genericPartitionMap1));
+ ret = -EIO;
+ goto out_bh;
+ }
+ ret = udf_sb_alloc_partition_maps(sb, part_map_count);
if (ret)
goto out_bh;
--
2.43.0
