diff options
| -rw-r--r-- | fs/fat/fat.c | 49 | ||||
| -rw-r--r-- | include/fat.h | 4 |
2 files changed, 41 insertions, 12 deletions
diff --git a/fs/fat/fat.c b/fs/fat/fat.c index 003666eae..744e96184 100644 --- a/fs/fat/fat.c +++ b/fs/fat/fat.c @@ -439,11 +439,19 @@ get_vfatname (fsdata *mydata, int curclust, __u8 *cluster, { dir_entry *realdent; dir_slot *slotptr = (dir_slot *)retdent; - __u8 *nextclust = cluster + mydata->clust_size * SECTOR_SIZE; + __u8 *buflimit = cluster + ((curclust == 0) ? + LINEAR_PREFETCH_SIZE : + (mydata->clust_size * SECTOR_SIZE) + ); __u8 counter = (slotptr->id & ~LAST_LONG_ENTRY_MASK) & 0xff; int idx = 0; - while ((__u8 *)slotptr < nextclust) { + if (counter > VFAT_MAXSEQ) { + debug("Error: VFAT name is too long\n"); + return -1; + } + + while ((__u8 *)slotptr < buflimit) { if (counter == 0) break; if (((slotptr->id & ~LAST_LONG_ENTRY_MASK) & 0xff) != counter) @@ -452,10 +460,11 @@ get_vfatname (fsdata *mydata, int curclust, __u8 *cluster, counter--; } - if ((__u8 *)slotptr >= nextclust) { + if ((__u8 *)slotptr >= buflimit) { dir_slot *slotptr2; - slotptr--; + if (curclust == 0) + return -1; curclust = get_fatent(mydata, curclust); if (CHECK_CLUST(curclust, mydata->fatsize)) { debug("curclust: 0x%x\n", curclust); @@ -470,14 +479,19 @@ get_vfatname (fsdata *mydata, int curclust, __u8 *cluster, } slotptr2 = (dir_slot *)get_vfatname_block; - while (slotptr2->id > 0x01) + while (counter > 0) { + if (((slotptr2->id & ~LAST_LONG_ENTRY_MASK) + & 0xff) != counter) + return -1; slotptr2++; + counter--; + } /* Save the real directory entry */ - realdent = (dir_entry *)slotptr2 + 1; - while ((__u8 *)slotptr2 >= get_vfatname_block) { - slot2str(slotptr2, l_name, &idx); + realdent = (dir_entry *)slotptr2; + while ((__u8 *)slotptr2 > get_vfatname_block) { slotptr2--; + slot2str(slotptr2, l_name, &idx); } } else { /* Save the real directory entry */ @@ -549,7 +563,7 @@ static dir_entry *get_dentfromdir (fsdata *mydata, int startsect, dentptr = (dir_entry *)get_dentfromdir_block; for (i = 0; i < DIRENTSPERCLUST; i++) { - char s_name[14], l_name[256]; + char s_name[14], l_name[VFAT_MAXLEN_BYTES]; l_name[0] = '\0'; if (dentptr->name[0] == DELETED_FLAG) { @@ -841,7 +855,11 @@ do_fat_read (const char *filename, void *buffer, unsigned long maxsize, debug("FAT read sect=%d, clust_size=%d, DIRENTSPERBLOCK=%d\n", cursect, mydata->clust_size, DIRENTSPERBLOCK); - if (disk_read(cursect, mydata->clust_size, do_fat_read_block) < 0) { + if (disk_read(cursect, + (mydata->fatsize == 32) ? + (mydata->clust_size) : + LINEAR_PREFETCH_SIZE, + do_fat_read_block) < 0) { debug("Error: reading rootdir block\n"); return -1; } @@ -849,9 +867,13 @@ do_fat_read (const char *filename, void *buffer, unsigned long maxsize, dentptr = (dir_entry *) do_fat_read_block; for (i = 0; i < DIRENTSPERBLOCK; i++) { - char s_name[14], l_name[256]; + char s_name[14], l_name[VFAT_MAXLEN_BYTES]; l_name[0] = '\0'; + if (dentptr->name[0] == DELETED_FLAG) { + dentptr++; + continue; + } if ((dentptr->attr & ATTR_VOLUME)) { #ifdef CONFIG_SUPPORT_VFAT if ((dentptr->attr & ATTR_VFAT) && @@ -859,7 +881,10 @@ do_fat_read (const char *filename, void *buffer, unsigned long maxsize, prevcksum = ((dir_slot *)dentptr)->alias_checksum; - get_vfatname(mydata, 0, + get_vfatname(mydata, + (mydata->fatsize == 32) ? + root_cluster : + 0, do_fat_read_block, dentptr, l_name); diff --git a/include/fat.h b/include/fat.h index de48afd73..afb2116e8 100644 --- a/include/fat.h +++ b/include/fat.h @@ -30,6 +30,10 @@ #include <asm/byteorder.h> #define CONFIG_SUPPORT_VFAT +/* Maximum Long File Name length supported here is 128 UTF-16 code units */ +#define VFAT_MAXLEN_BYTES 256 /* Maximum LFN buffer in bytes */ +#define VFAT_MAXSEQ 9 /* Up to 9 of 13 2-byte UTF-16 entries */ +#define LINEAR_PREFETCH_SIZE (SECTOR_SIZE*2) /* Prefetch buffer size */ #define SECTOR_SIZE FS_BLOCK_SIZE |