This patch fixes several issues where sector offsets can overflow due to being limited to 16-bits. There are many cases which can cause an overflow, including large FAT32 partitions and partitions that start at a sufficiently large offset on the storage device.
Numerous issues were observed and fixed when a 64GB FAT32 filesystem was accessed due to truncation.
Signed-off-by: Aaron Williams aaron.williams@caviumnetworks.com --- include/fat.h | 10 +++++----- 1 files changed, 5 insertions(+), 5 deletions(-)
diff --git a/include/fat.h b/include/fat.h index 4c92442..7215628 100644 --- a/include/fat.h +++ b/include/fat.h @@ -178,12 +178,12 @@ typedef struct dir_slot { typedef struct { __u8 *fatbuf; /* Current FAT buffer */ int fatsize; /* Size of FAT in bits */ - __u16 fatlength; /* Length of FAT in sectors */ - __u16 fat_sect; /* Starting sector of the FAT */ - __u16 rootdir_sect; /* Start sector of root directory */ - __u16 sect_size; /* Size of sectors in bytes */ + __u32 fat_sect; /* Starting sector of the FAT */ + __u32 rootdir_sect; /* Start sector of root directory */ + __u32 fatlength; /* Length of FAT in sectors */ __u16 clust_size; /* Size of clusters in sectors */ - short data_begin; /* The sector of the first cluster, can be negative */ + __u16 sect_size; /* Size of sectors in bytes */ + int data_begin; /* The sector of the first cluster, can be negative */ int fatbufnum; /* Used by get_fatent, init to -1 */ } fsdata;