hfsplus: fix overflow in hfsplus_read_wrapper
For partitions larger than 2TB or at such an offset the hfs wrapper code
in hfsplus might overflow the range representable in a 32-bit
data type. Make sure we use a sector_t for the arithmetics leading to it.
I'm not sure this code can be readed at all as hfs itself never supported
such large volumes.
Signed-off-by: Christoph Hellwig <hch@tuxera.com>
diff --git a/fs/hfsplus/wrapper.c b/fs/hfsplus/wrapper.c
index 4ac88ff..4b86468 100644
--- a/fs/hfsplus/wrapper.c
+++ b/fs/hfsplus/wrapper.c
@@ -172,8 +172,9 @@
if (!hfsplus_read_mdb(sbi->s_vhdr, &wd))
goto out_free_backup_vhdr;
wd.ablk_size >>= HFSPLUS_SECTOR_SHIFT;
- part_start += wd.ablk_start + wd.embed_start * wd.ablk_size;
- part_size = wd.embed_count * wd.ablk_size;
+ part_start += (sector_t)wd.ablk_start +
+ (sector_t)wd.embed_start * wd.ablk_size;
+ part_size = (sector_t)wd.embed_count * wd.ablk_size;
goto reread;
default:
/*