FAT: get_fatent: Fix FAT boundary check

startblock must be taken into account in order not to read past the
end of the FAT.

Signed-off-by: Benoît Thébaudeau <benoit.thebaudeau@advansee.com>
Cc: Wolfgang Denk <wd@denx.de>

diff --git a/fs/fat/fat.c b/fs/fat/fat.c
index 9f83572..87a1623 100644 (file)
--- a/fs/fat/fat.c
+++ b/fs/fat/fat.c
@@ -207,8 +207,8 @@ static __u32 get_fatent(fsdata *mydata, __u32 entry)
                __u32 fatlength = mydata->fatlength;
                __u32 startblock = bufnum * FATBUFBLOCKS;
 
-               if (getsize > fatlength)
-                       getsize = fatlength;
+               if (startblock + getsize > fatlength)
+                       getsize = fatlength - startblock;
 
                fatlength *= mydata->sect_size; /* We want it in bytes now */
                startblock += mydata->fat_sect; /* Offset from start of disk */