[PATCH v3 5/7] udf: Adjust UDF_NAME_LEN to better reflect actual restrictions

[Andrew Gabbasov]

Actual name length restriction is 254 bytes, this is used in 'ustr'
structure, and this is what fits into UDF File Ident structures.
And in most cases the constant is used as UDF_NAME_LEN-2.
So, it's better to just modify the constant to make it closer
to reality.

Also, in some cases it's useful to have a separate constant for
the maximum length of file name field in CS0 encoding in UDF File
Ident structures.

Also, remove the unused UDF_PATH_LEN constant.

Signed-off-by: Andrew Gabbasov <andrew_gabbasov@xxxxxxxxxx>
---
 fs/udf/namei.c   | 10 +++++-----
 fs/udf/super.c   |  2 +-
 fs/udf/udfdecl.h |  6 +++---
 fs/udf/unicode.c |  6 +++---
 4 files changed, 12 insertions(+), 12 deletions(-)

diff --git a/fs/udf/namei.c b/fs/udf/namei.c
index 6192070..8527368 100644
--- a/fs/udf/namei.c
+++ b/fs/udf/namei.c
@@ -291,7 +291,7 @@ static struct dentry *udf_lookup(struct inode *dir, struct dentry *dentry,
 	struct udf_fileident_bh fibh;
 	struct fileIdentDesc *fi;
 
-	if (dentry->d_name.len > UDF_NAME_LEN - 2)
+	if (dentry->d_name.len > UDF_NAME_LEN)
 		return ERR_PTR(-ENAMETOOLONG);
 
 #ifdef UDF_RECOVERY
@@ -351,7 +351,7 @@ static struct fileIdentDesc *udf_add_entry(struct inode *dir,
 	struct udf_inode_info *dinfo;
 
 	fibh->sbh = fibh->ebh = NULL;
-	name = kmalloc(UDF_NAME_LEN, GFP_NOFS);
+	name = kmalloc(UDF_NAME_LEN_CS0, GFP_NOFS);
 	if (!name) {
 		*err = -ENOMEM;
 		goto out_err;
@@ -364,7 +364,7 @@ static struct fileIdentDesc *udf_add_entry(struct inode *dir,
 		}
 		namelen = udf_put_filename(sb, dentry->d_name.name,
 					   dentry->d_name.len,
-					   name, UDF_NAME_LEN);
+					   name, UDF_NAME_LEN_CS0);
 		if (!namelen) {
 			*err = -ENAMETOOLONG;
 			goto out_err;
@@ -915,7 +915,7 @@ static int udf_symlink(struct inode *dir, struct dentry *dentry,
 
 	iinfo = UDF_I(inode);
 	down_write(&iinfo->i_data_sem);
-	name = kmalloc(UDF_NAME_LEN, GFP_NOFS);
+	name = kmalloc(UDF_NAME_LEN_CS0, GFP_NOFS);
 	if (!name) {
 		err = -ENOMEM;
 		goto out_no_entry;
@@ -999,7 +999,7 @@ static int udf_symlink(struct inode *dir, struct dentry *dentry,
 		if (pc->componentType == 5) {
 			namelen = udf_put_filename(sb, compstart,
 						   symname - compstart,
-						   name, UDF_NAME_LEN);
+						   name, UDF_NAME_LEN_CS0);
 			if (!namelen)
 				goto out_no_entry;
 
diff --git a/fs/udf/super.c b/fs/udf/super.c
index 81155b9..a801721 100644
--- a/fs/udf/super.c
+++ b/fs/udf/super.c
@@ -2348,7 +2348,7 @@ static int udf_statfs(struct dentry *dentry, struct kstatfs *buf)
 					  le32_to_cpu(lvidiu->numDirs)) : 0)
 			+ buf->f_bfree;
 	buf->f_ffree = buf->f_bfree;
-	buf->f_namelen = UDF_NAME_LEN - 2;
+	buf->f_namelen = UDF_NAME_LEN;
 	buf->f_fsid.val[0] = (u32)id;
 	buf->f_fsid.val[1] = (u32)(id >> 32);
 
diff --git a/fs/udf/udfdecl.h b/fs/udf/udfdecl.h
index 35591e3..2a70a63 100644
--- a/fs/udf/udfdecl.h
+++ b/fs/udf/udfdecl.h
@@ -49,8 +49,8 @@ extern __printf(3, 4) void _udf_warn(struct super_block *sb,
 #define UDF_EXTENT_FLAG_MASK	0xC0000000
 
 #define UDF_NAME_PAD		4
-#define UDF_NAME_LEN		256
-#define UDF_PATH_LEN		1023
+#define UDF_NAME_LEN		254
+#define UDF_NAME_LEN_CS0	255
 
 static inline size_t udf_file_entry_alloc_offset(struct inode *inode)
 {
@@ -109,7 +109,7 @@ struct generic_desc {
 
 struct ustr {
 	uint8_t u_cmpID;
-	uint8_t u_name[UDF_NAME_LEN - 2];
+	uint8_t u_name[UDF_NAME_LEN];
 	uint8_t u_len;
 };
 
diff --git a/fs/udf/unicode.c b/fs/udf/unicode.c
index ed48040..d6c1827 100644
--- a/fs/udf/unicode.c
+++ b/fs/udf/unicode.c
@@ -33,7 +33,7 @@ static int udf_translate_to_linux(uint8_t *, int, uint8_t *, int, uint8_t *,
 
 static int udf_char_to_ustr(struct ustr *dest, const uint8_t *src, int strlen)
 {
-	if ((!dest) || (!src) || (!strlen) || (strlen > UDF_NAME_LEN - 2))
+	if ((!dest) || (!src) || (!strlen) || (strlen > UDF_NAME_LEN))
 		return 0;
 
 	memset(dest, 0, sizeof(struct ustr));
@@ -184,14 +184,14 @@ static int udf_name_from_CS0(struct ustr *utf_o,
 
 	ocu = ocu_i->u_name;
 	utf_o->u_len = 0;
-	for (i = 0; (i < ocu_len) && (utf_o->u_len <= (UDF_NAME_LEN - 3));) {
+	for (i = 0; (i < ocu_len) && (utf_o->u_len < UDF_NAME_LEN);) {
 		/* Expand OSTA compressed Unicode to Unicode */
 		uint32_t c = ocu[i++];
 		if (cmp_id == 16)
 			c = (c << 8) | ocu[i++];
 
 		len = conv_f(c, &utf_o->u_name[utf_o->u_len],
-			     UDF_NAME_LEN - 2 - utf_o->u_len);
+			     UDF_NAME_LEN - utf_o->u_len);
 		/* Valid character? */
 		if (len >= 0)
 			utf_o->u_len += len;
-- 
2.1.0