diff options
| -rw-r--r-- | dir.c | 35 |
1 files changed, 25 insertions, 10 deletions
@@ -427,7 +427,8 @@ checksize(struct bootblock *boot, u_char *p, */ struct cluster_chain_descriptor *fat,tofind; struct fatcache *cache; - int32_t physicalSize; + u_int64_t physicalSize; + const u_int64_t max_physical_size = 0x100000000; if (dir->head == CLUST_FREE) physicalSize = 0; @@ -440,12 +441,29 @@ checksize(struct bootblock *boot, u_char *p, pwarn("Can't find the cluster chain with head(%u) \n",dir->head); return FSERROR; } - physicalSize = fat->length * boot->ClusterSize; + physicalSize = ((u_int64_t)fat->length) * ((u_int64_t)boot->ClusterSize); } - if (physicalSize < dir->size) { + /* + *The file size means how much useful data the file contains + *FAT use 4 bytes to describe the file size, so the max file size is (4GBytes - 1). + *The physical size means how much space the file use in disk. The max physical + *size is 4GBytes. + * + *For example, we create a new file in WINDOWS,which size is 100Bytes, but i + *use 4KB in disk. Here 100B is file size ,and 4KB is physical size. + * + *Physical size = (file size + boot->ClusterSize - 1) & (boot->ClusterSize - 1) + */ + if (physicalSize > max_physical_size) { + fsck_err("file %s physical size exceed 4 GBytes. %llu\n", + fullpath(dir), physicalSize); + return FSERROR; + } + + if (physicalSize < (u_int64_t)dir->size) { pwarn("size of %s is %u, should at most be %u\n", fullpath(dir), dir->size, physicalSize); - fsck_debug("physicalSize:%d ,dir->size = %d ,dir->head:0x%x\n",physicalSize,dir->size,dir->head); + fsck_debug("physicalSize:%llu ,dir->size = %d ,dir->head:0x%x\n",physicalSize,dir->size,dir->head); if (ask(1, "Truncate")) { dir->size = physicalSize; p[28] = (u_char)physicalSize; @@ -455,10 +473,10 @@ checksize(struct bootblock *boot, u_char *p, return FSDIRMOD; } else return FSERROR; - } else if (physicalSize - dir->size >= boot->ClusterSize) { + } else if (physicalSize - (u_int64_t)dir->size >= (u_int64_t)boot->ClusterSize) { pwarn("%s has too many clusters allocated\n", fullpath(dir)); - fsck_debug("physicalSize:%d ,dir->size = %d ,dir->head:0x%x\n",physicalSize,dir->size,dir->head); + fsck_debug("physicalSize:%llu ,dir->size = %d ,dir->head:0x%x\n",physicalSize,dir->size,dir->head); if (ask(1, "Drop superfluous clusters")) { cl_t cl; u_int32_t sz = 0; @@ -470,12 +488,9 @@ checksize(struct bootblock *boot, u_char *p, if(cl == CLUST_EOF) break; } - //cache = Find_nextclus(fat,cl,&cl); if(!cache && !cl) return FSERROR; - //TODO: i don't no why exec clearchain here.when cl != fat.head,clear do nothing - //clearchain(boot, fat,cl); - //if trunc it ,when next fsck ,the rest will locate in LOST.DIR + Trunc(boot,fat,cl); fsck_debug("after truncate ,fat->length = %d \n",fat->length); return FSFATMOD; |