Fix checking fat32 cluster size.

This fixes the cluster size tests in the FAT32 file system.
The current implementation of VFAT support doesn't work if the
referred cluster has an offset > 16bit representation, causing
"fatload" and "fatls" commands etc. to fail.

Signed-off-by: michael trimarchi <trimarchi@gandalf.sssup.it>
This commit is contained in:
michael 2008-03-02 23:33:46 +01:00 committed by Wolfgang Denk
parent 661bad63a0
commit 8ce4e5c2c0
2 changed files with 6 additions and 5 deletions

View file

@ -352,7 +352,7 @@ get_contents(fsdata *mydata, dir_entry *dentptr, __u8 *buffer,
newclust = get_fatent(mydata, endclust);
if((newclust -1)!=endclust)
goto getit;
if (newclust <= 0x0001 || newclust >= 0xfff0) {
if (CHECK_CLUST(newclust, mydata->fatsize)) {
FAT_DPRINT("curclust: 0x%x\n", newclust);
FAT_DPRINT("Invalid FAT entry\n");
return gotsize;
@ -387,7 +387,7 @@ getit:
filesize -= actsize;
buffer += actsize;
curclust = get_fatent(mydata, endclust);
if (curclust <= 0x0001 || curclust >= 0xfff0) {
if (CHECK_CLUST(curclust, mydata->fatsize)) {
FAT_DPRINT("curclust: 0x%x\n", curclust);
FAT_ERROR("Invalid FAT entry\n");
return gotsize;
@ -459,7 +459,7 @@ get_vfatname(fsdata *mydata, int curclust, __u8 *cluster,
slotptr--;
curclust = get_fatent(mydata, curclust);
if (curclust <= 0x0001 || curclust >= 0xfff0) {
if (CHECK_CLUST(curclust, mydata->fatsize)) {
FAT_DPRINT("curclust: 0x%x\n", curclust);
FAT_ERROR("Invalid FAT entry\n");
return -1;
@ -652,7 +652,7 @@ static dir_entry *get_dentfromdir (fsdata * mydata, int startsect,
return retdent;
}
curclust = get_fatent (mydata, curclust);
if (curclust <= 0x0001 || curclust >= 0xfff0) {
if (CHECK_CLUST(curclust, mydata->fatsize)) {
FAT_DPRINT ("curclust: 0x%x\n", curclust);
FAT_ERROR ("Invalid FAT entry\n");
return NULL;

View file

@ -111,7 +111,8 @@
#define START(dent) (FAT2CPU16((dent)->start) \
+ (mydata->fatsize != 32 ? 0 : \
(FAT2CPU16((dent)->starthi) << 16)))
#define CHECK_CLUST(x, fatsize) ((x) <= 1 || \
(x) >= ((fatsize) != 32 ? 0xfff0 : 0xffffff0))
typedef struct boot_sector {
__u8 ignored[3]; /* Bootstrap code */