[ 138/184] fat: Fix stat->f_namelen

From: Willy Tarreau
Date: Tue Jun 04 2013 - 18:56:41 EST


2.6.32-longterm review patch. If anyone has any objections, please let me know.

------------------

From: Kevin Dankwardt <k@xxxxxxxxxxxxxx>

commit eeb5b4ae81f4a750355fa0c15f4fea22fdf83be1 upstream.

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@xxxxxxxxxxxxxx>
Signed-off-by: OGAWA Hirofumi <hirofumi@xxxxxxxxxxxxxxxxxx>
Signed-off-by: Willy Tarreau <w@xxxxxx>
---
fs/fat/inode.c | 2 +-
fs/fat/namei_vfat.c | 6 +++---
include/linux/msdos_fs.h | 3 ++-
3 files changed, 6 insertions(+), 5 deletions(-)

diff --git a/fs/fat/inode.c b/fs/fat/inode.c
index 76b7961..c187e92 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 72646e2..67b3df1 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 ce38f1c..34066e6 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 */
--
1.7.12.2.21.g234cd45.dirty



--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/