fat: Fix stat->f_namelen

I found that the length of a file name when created cannot exceed 255
characters, yet, pathconf(), via statfs(), returns the maximum as 260.

Signed-off-by: Kevin Dankwardt <k@kcomputing.com>
Signed-off-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>

3 files changed, 6 insertions, 5 deletions

diff --git a/fs/fat/inode.c b/fs/fat/inode.c
index 14da530b05ca..d0a504c8feef 100644
--- a/fs/fat/inode.c
+++ b/fs/fat/inode.c
@@ -558,7 +558,7 @@ static int fat_statfs(struct dentry *dentry, struct kstatfs *buf)
         buf->f_bavail = sbi->free_clusters;
         buf->f_fsid.val[0] = (u32)id;
         buf->f_fsid.val[1] = (u32)(id >> 32);
-        buf->f_namelen = sbi->options.isvfat ? 260 : 12;
+        buf->f_namelen = sbi->options.isvfat ? FAT_LFN_LEN : 12;
 
         return 0;
 }
diff --git a/fs/fat/namei_vfat.c b/fs/fat/namei_vfat.c
index 411c192a05fa..c1ef50154868 100644
--- a/fs/fat/namei_vfat.c
+++ b/fs/fat/namei_vfat.c
@@ -502,14 +502,14 @@ xlate_to_uni(const unsigned char *name, int len, unsigned char *outname,
                 *outlen = utf8s_to_utf16s(name, len, (wchar_t *)outname);
                 if (*outlen < 0)
                         return *outlen;
-                else if (*outlen > 255)
+                else if (*outlen > FAT_LFN_LEN)
                         return -ENAMETOOLONG;
 
                 op = &outname[*outlen * sizeof(wchar_t)];
         } else {
                 if (nls) {
                         for (i = 0, ip = name, op = outname, *outlen = 0;
-                             i < len && *outlen <= 255;
+                             i < len && *outlen <= FAT_LFN_LEN;
                              *outlen += 1)
                         {
                                 if (escape && (*ip == ':')) {
@@ -549,7 +549,7 @@ xlate_to_uni(const unsigned char *name, int len, unsigned char *outname,
                                 return -ENAMETOOLONG;
                 } else {
                         for (i = 0, ip = name, op = outname, *outlen = 0;
-                             i < len && *outlen <= 255;
+                             i < len && *outlen <= FAT_LFN_LEN;
                              i++, *outlen += 1)
                         {
                                 *op++ = *ip++;
diff --git a/include/linux/msdos_fs.h b/include/linux/msdos_fs.h
index ce38f1caa5e1..34066e65fdeb 100644
--- a/include/linux/msdos_fs.h
+++ b/include/linux/msdos_fs.h
@@ -15,6 +15,7 @@
 #define MSDOS_DPB_BITS  4               /* log2(MSDOS_DPB) */
 #define MSDOS_DPS       (SECTOR_SIZE / sizeof(struct msdos_dir_entry))
 #define MSDOS_DPS_BITS  4               /* log2(MSDOS_DPS) */
+#define MSDOS_LONGNAME  256             /* maximum name length */
 #define CF_LE_W(v)      le16_to_cpu(v)
 #define CF_LE_L(v)      le32_to_cpu(v)
 #define CT_LE_W(v)      cpu_to_le16(v)
@@ -47,8 +48,8 @@
 #define DELETED_FLAG    0xe5    /* marks file as deleted when in name[0] */
 #define IS_FREE(n)      (!*(n) || *(n) == DELETED_FLAG)
 
+#define FAT_LFN_LEN     255     /* maximum long name length */
 #define MSDOS_NAME      11      /* maximum name length */
-#define MSDOS_LONGNAME  256     /* maximum name length */
 #define MSDOS_SLOTS     21      /* max # of slots for short and long names */
 #define MSDOS_DOT       ".          "   /* ".", padded to MSDOS_NAME chars */
 #define MSDOS_DOTDOT    "..         "   /* "..", padded to MSDOS_NAME chars */