From 8ce4e5c2c02cb7e8adddf7b651d3050d81ce4c1d Mon Sep 17 00:00:00 2001 From: michael Date: Sun, 2 Mar 2008 23:33:46 +0100 Subject: [PATCH] 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 --- fs/fat/fat.c | 8 ++++---- include/fat.h | 3 ++- 2 files changed, 6 insertions(+), 5 deletions(-) diff --git a/fs/fat/fat.c b/fs/fat/fat.c index c1e57412d7..49c78ed79a 100644 --- a/fs/fat/fat.c +++ b/fs/fat/fat.c @@ -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; diff --git a/include/fat.h b/include/fat.h index 92638d535e..f993ccab1c 100644 --- a/include/fat.h +++ b/include/fat.h @@ -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 */ -- 2.39.5