These changes are the raw update to linux-4.4.6-rt14. Kernel sources

are taken from kernel.org, and rt patch from the rt wiki download page.

During the rebasing, the following patch collided:

Force tick interrupt and get rid of softirq magic(I70131fb85).

Collisions have been removed because its logic was found on the
source already.

Change-Id: I7f57a4081d9deaa0d9ccfc41a6c8daccdee3b769
Signed-off-by: José Pekkarinen <jose.pekkarinen@nokia.com>

8 files changed, 165 insertions, 76 deletions

diff --git a/kernel/fs/udf/dir.c b/kernel/fs/udf/dir.c
index 541a12b57..541d9c650 100644
--- a/kernel/fs/udf/dir.c
+++ b/kernel/fs/udf/dir.c
@@ -168,7 +168,7 @@ static int udf_readdir(struct file *file, struct dir_context *ctx)
 		}
 
 		flen = udf_get_filename(sb, nameptr, lfi, fname, UDF_NAME_LEN);
-		if (!flen)
+		if (flen < 0)
 			continue;
 
 		tloc = lelb_to_cpu(cfi.icb.extLocation);
diff --git a/kernel/fs/udf/file.c b/kernel/fs/udf/file.c
index 7a95b8fed..bddf3d071 100644
--- a/kernel/fs/udf/file.c
+++ b/kernel/fs/udf/file.c
@@ -152,8 +152,6 @@ out:
 	mutex_unlock(&inode->i_mutex);
 
 	if (retval > 0) {
-		ssize_t err;
-
 		mark_inode_dirty(inode);
 		err = generic_write_sync(file, iocb->ki_pos - retval, retval);
 		if (err < 0)
diff --git a/kernel/fs/udf/inode.c b/kernel/fs/udf/inode.c
index 6afac3d56..566df9b5a 100644
--- a/kernel/fs/udf/inode.c
+++ b/kernel/fs/udf/inode.c
@@ -1652,17 +1652,9 @@ static int udf_update_inode(struct inode *inode, int do_sync)
 		       iinfo->i_ext.i_data, inode->i_sb->s_blocksize -
 					sizeof(struct unallocSpaceEntry));
 		use->descTag.tagIdent = cpu_to_le16(TAG_IDENT_USE);
-		use->descTag.tagLocation =
-				cpu_to_le32(iinfo->i_location.logicalBlockNum);
-		crclen = sizeof(struct unallocSpaceEntry) +
-				iinfo->i_lenAlloc - sizeof(struct tag);
-		use->descTag.descCRCLength = cpu_to_le16(crclen);
-		use->descTag.descCRC = cpu_to_le16(crc_itu_t(0, (char *)use +
-							   sizeof(struct tag),
-							   crclen));
-		use->descTag.tagChecksum = udf_tag_checksum(&use->descTag);
+		crclen = sizeof(struct unallocSpaceEntry);
 
-		goto out;
+		goto finish;
 	}
 
 	if (UDF_QUERY_FLAG(inode->i_sb, UDF_FLAG_UID_FORGET))
@@ -1782,6 +1774,8 @@ static int udf_update_inode(struct inode *inode, int do_sync)
 		efe->descTag.tagIdent = cpu_to_le16(TAG_IDENT_EFE);
 		crclen = sizeof(struct extendedFileEntry);
 	}
+
+finish:
 	if (iinfo->i_strat4096) {
 		fe->icbTag.strategyType = cpu_to_le16(4096);
 		fe->icbTag.strategyParameter = cpu_to_le16(1);
@@ -1791,7 +1785,9 @@ static int udf_update_inode(struct inode *inode, int do_sync)
 		fe->icbTag.numEntries = cpu_to_le16(1);
 	}
 
-	if (S_ISDIR(inode->i_mode))
+	if (iinfo->i_use)
+		fe->icbTag.fileType = ICBTAG_FILE_TYPE_USE;
+	else if (S_ISDIR(inode->i_mode))
 		fe->icbTag.fileType = ICBTAG_FILE_TYPE_DIRECTORY;
 	else if (S_ISREG(inode->i_mode))
 		fe->icbTag.fileType = ICBTAG_FILE_TYPE_REGULAR;
@@ -1828,7 +1824,6 @@ static int udf_update_inode(struct inode *inode, int do_sync)
 						  crclen));
 	fe->descTag.tagChecksum = udf_tag_checksum(&fe->descTag);
 
-out:
 	set_buffer_uptodate(bh);
 	unlock_buffer(bh);
 
@@ -2052,14 +2047,29 @@ void udf_write_aext(struct inode *inode, struct extent_position *epos,
 		epos->offset += adsize;
 }
 
+/*
+ * Only 1 indirect extent in a row really makes sense but allow upto 16 in case
+ * someone does some weird stuff.
+ */
+#define UDF_MAX_INDIR_EXTS 16
+
 int8_t udf_next_aext(struct inode *inode, struct extent_position *epos,
 		     struct kernel_lb_addr *eloc, uint32_t *elen, int inc)
 {
 	int8_t etype;
+	unsigned int indirections = 0;
 
 	while ((etype = udf_current_aext(inode, epos, eloc, elen, inc)) ==
 	       (EXT_NEXT_EXTENT_ALLOCDECS >> 30)) {
 		int block;
+
+		if (++indirections > UDF_MAX_INDIR_EXTS) {
+			udf_err(inode->i_sb,
+				"too many indirect extents in inode %lu\n",
+				inode->i_ino);
+			return -1;
+		}
+
 		epos->block = *eloc;
 		epos->offset = sizeof(struct allocExtDesc);
 		brelse(epos->bh);
diff --git a/kernel/fs/udf/namei.c b/kernel/fs/udf/namei.c
index 5c03f0dfb..c97b5a8d1 100644
--- a/kernel/fs/udf/namei.c
+++ b/kernel/fs/udf/namei.c
@@ -138,6 +138,25 @@ int udf_write_fi(struct inode *inode, struct fileIdentDesc *cfi,
 	return 0;
 }
 
+/**
+ * udf_find_entry - find entry in given directory.
+ *
+ * @dir:	directory inode to search in
+ * @child:	qstr of the name
+ * @fibh:	buffer head / inode with file identifier descriptor we found
+ * @cfi:	found file identifier descriptor with given name
+ *
+ * This function searches in the directory @dir for a file name @child. When
+ * found, @fibh points to the buffer head(s) (bh is NULL for in ICB
+ * directories) containing the file identifier descriptor (FID). In that case
+ * the function returns pointer to the FID in the buffer or inode - but note
+ * that FID may be split among two buffers (blocks) so accessing it via that
+ * pointer isn't easily possible. This pointer can be used only as an iterator
+ * for other directory manipulation functions. For inspection of the FID @cfi
+ * can be used - the found FID is copied there.
+ *
+ * Returns pointer to FID, NULL when nothing found, or error code.
+ */
 static struct fileIdentDesc *udf_find_entry(struct inode *dir,
 					    const struct qstr *child,
 					    struct udf_fileident_bh *fibh,
@@ -167,8 +186,11 @@ static struct fileIdentDesc *udf_find_entry(struct inode *dir,
 	fibh->soffset = fibh->eoffset = f_pos & (sb->s_blocksize - 1);
 	if (dinfo->i_alloc_type != ICBTAG_FLAG_AD_IN_ICB) {
 		if (inode_bmap(dir, f_pos >> sb->s_blocksize_bits, &epos,
-		    &eloc, &elen, &offset) != (EXT_RECORDED_ALLOCATED >> 30))
+		    &eloc, &elen, &offset) != (EXT_RECORDED_ALLOCATED >> 30)) {
+			fi = ERR_PTR(-EIO);
 			goto out_err;
+		}
+
 		block = udf_get_lb_pblock(sb, &eloc, offset);
 		if ((++offset << sb->s_blocksize_bits) < elen) {
 			if (dinfo->i_alloc_type == ICBTAG_FLAG_AD_SHORT)
@@ -179,19 +201,25 @@ static struct fileIdentDesc *udf_find_entry(struct inode *dir,
 			offset = 0;
 
 		fibh->sbh = fibh->ebh = udf_tread(sb, block);
-		if (!fibh->sbh)
+		if (!fibh->sbh) {
+			fi = ERR_PTR(-EIO);
 			goto out_err;
+		}
 	}
 
 	fname = kmalloc(UDF_NAME_LEN, GFP_NOFS);
-	if (!fname)
+	if (!fname) {
+		fi = ERR_PTR(-ENOMEM);
 		goto out_err;
+	}
 
 	while (f_pos < size) {
 		fi = udf_fileident_read(dir, &f_pos, fibh, cfi, &epos, &eloc,
 					&elen, &offset);
-		if (!fi)
+		if (!fi) {
+			fi = ERR_PTR(-EIO);
 			goto out_err;
+		}
 
 		liu = le16_to_cpu(cfi->lengthOfImpUse);
 		lfi = cfi->lengthFileIdent;
@@ -234,12 +262,17 @@ static struct fileIdentDesc *udf_find_entry(struct inode *dir,
 			continue;
 
 		flen = udf_get_filename(sb, nameptr, lfi, fname, UDF_NAME_LEN);
-		if (flen && udf_match(flen, fname, child->len, child->name))
+		if (flen < 0) {
+			fi = ERR_PTR(flen);
+			goto out_err;
+		}
+
+		if (udf_match(flen, fname, child->len, child->name))
 			goto out_ok;
 	}
 
-out_err:
 	fi = NULL;
+out_err:
 	if (fibh->sbh != fibh->ebh)
 		brelse(fibh->ebh);
 	brelse(fibh->sbh);
@@ -256,6 +289,7 @@ static struct dentry *udf_lookup(struct inode *dir, struct dentry *dentry,
 	struct inode *inode = NULL;
 	struct fileIdentDesc cfi;
 	struct udf_fileident_bh fibh;
+	struct fileIdentDesc *fi;
 
 	if (dentry->d_name.len > UDF_NAME_LEN - 2)
 		return ERR_PTR(-ENAMETOOLONG);
@@ -275,7 +309,11 @@ static struct dentry *udf_lookup(struct inode *dir, struct dentry *dentry,
 	} else
 #endif /* UDF_RECOVERY */
 
-	if (udf_find_entry(dir, &dentry->d_name, &fibh, &cfi)) {
+	fi = udf_find_entry(dir, &dentry->d_name, &fibh, &cfi);
+	if (IS_ERR(fi))
+		return ERR_CAST(fi);
+
+	if (fi) {
 		struct kernel_lb_addr loc;
 
 		if (fibh.sbh != fibh.ebh)
@@ -774,8 +812,11 @@ static int udf_rmdir(struct inode *dir, struct dentry *dentry)
 
 	retval = -ENOENT;
 	fi = udf_find_entry(dir, &dentry->d_name, &fibh, &cfi);
-	if (!fi)
+	if (IS_ERR_OR_NULL(fi)) {
+		if (fi)
+			retval = PTR_ERR(fi);
 		goto out;
+	}
 
 	retval = -EIO;
 	tloc = lelb_to_cpu(cfi.icb.extLocation);
@@ -817,8 +858,12 @@ static int udf_unlink(struct inode *dir, struct dentry *dentry)
 
 	retval = -ENOENT;
 	fi = udf_find_entry(dir, &dentry->d_name, &fibh, &cfi);
-	if (!fi)
+
+	if (IS_ERR_OR_NULL(fi)) {
+		if (fi)
+			retval = PTR_ERR(fi);
 		goto out;
+	}
 
 	retval = -EIO;
 	tloc = lelb_to_cpu(cfi.icb.extLocation);
@@ -1049,24 +1094,30 @@ static int udf_rename(struct inode *old_dir, struct dentry *old_dentry,
 	struct udf_inode_info *old_iinfo = UDF_I(old_inode);
 
 	ofi = udf_find_entry(old_dir, &old_dentry->d_name, &ofibh, &ocfi);
-	if (ofi) {
-		if (ofibh.sbh != ofibh.ebh)
-			brelse(ofibh.ebh);
-		brelse(ofibh.sbh);
+	if (IS_ERR(ofi)) {
+		retval = PTR_ERR(ofi);
+		goto end_rename;
 	}
+
+	if (ofibh.sbh != ofibh.ebh)
+		brelse(ofibh.ebh);
+
+	brelse(ofibh.sbh);
 	tloc = lelb_to_cpu(ocfi.icb.extLocation);
 	if (!ofi || udf_get_lb_pblock(old_dir->i_sb, &tloc, 0)
 	    != old_inode->i_ino)
 		goto end_rename;
 
 	nfi = udf_find_entry(new_dir, &new_dentry->d_name, &nfibh, &ncfi);
-	if (nfi) {
-		if (!new_inode) {
-			if (nfibh.sbh != nfibh.ebh)
-				brelse(nfibh.ebh);
-			brelse(nfibh.sbh);
-			nfi = NULL;
-		}
+	if (IS_ERR(nfi)) {
+		retval = PTR_ERR(nfi);
+		goto end_rename;
+	}
+	if (nfi && !new_inode) {
+		if (nfibh.sbh != nfibh.ebh)
+			brelse(nfibh.ebh);
+		brelse(nfibh.sbh);
+		nfi = NULL;
 	}
 	if (S_ISDIR(old_inode->i_mode)) {
 		int offset = udf_ext0_offset(old_inode);
@@ -1221,7 +1272,7 @@ static struct dentry *udf_nfs_get_inode(struct super_block *sb, u32 block,
 static struct dentry *udf_fh_to_dentry(struct super_block *sb,
 				       struct fid *fid, int fh_len, int fh_type)
 {
-	if ((fh_len != 3 && fh_len != 5) ||
+	if (fh_len < 3 ||
 	    (fh_type != FILEID_UDF_WITH_PARENT &&
 	     fh_type != FILEID_UDF_WITHOUT_PARENT))
 		return NULL;
@@ -1233,7 +1284,7 @@ static struct dentry *udf_fh_to_dentry(struct super_block *sb,
 static struct dentry *udf_fh_to_parent(struct super_block *sb,
 				       struct fid *fid, int fh_len, int fh_type)
 {
-	if (fh_len != 5 || fh_type != FILEID_UDF_WITH_PARENT)
+	if (fh_len < 5 || fh_type != FILEID_UDF_WITH_PARENT)
 		return NULL;
 
 	return udf_nfs_get_inode(sb, fid->udf.parent_block,
diff --git a/kernel/fs/udf/super.c b/kernel/fs/udf/super.c
index 6299f3419..81155b9b4 100644
--- a/kernel/fs/udf/super.c
+++ b/kernel/fs/udf/super.c
@@ -927,17 +927,23 @@ static int udf_load_pvoldesc(struct super_block *sb, sector_t block)
 #endif
 	}
 
-	if (!udf_build_ustr(instr, pvoldesc->volIdent, 32))
-		if (udf_CS0toUTF8(outstr, instr)) {
-			strncpy(UDF_SB(sb)->s_volume_ident, outstr->u_name,
-				outstr->u_len > 31 ? 31 : outstr->u_len);
-			udf_debug("volIdent[] = '%s'\n",
-				  UDF_SB(sb)->s_volume_ident);
-		}
+	if (!udf_build_ustr(instr, pvoldesc->volIdent, 32)) {
+		ret = udf_CS0toUTF8(outstr, instr);
+		if (ret < 0)
+			goto out_bh;
+
+		strncpy(UDF_SB(sb)->s_volume_ident, outstr->u_name,
+			outstr->u_len > 31 ? 31 : outstr->u_len);
+		udf_debug("volIdent[] = '%s'\n", UDF_SB(sb)->s_volume_ident);
+	}
+
+	if (!udf_build_ustr(instr, pvoldesc->volSetIdent, 128)) {
+		ret = udf_CS0toUTF8(outstr, instr);
+		if (ret < 0)
+			goto out_bh;
 
-	if (!udf_build_ustr(instr, pvoldesc->volSetIdent, 128))
-		if (udf_CS0toUTF8(outstr, instr))
-			udf_debug("volSetIdent[] = '%s'\n", outstr->u_name);
+		udf_debug("volSetIdent[] = '%s'\n", outstr->u_name);
+	}
 
 	ret = 0;
 out_bh:
@@ -2064,6 +2070,7 @@ static int udf_fill_super(struct super_block *sb, void *options, int silent)
 	struct udf_options uopt;
 	struct kernel_lb_addr rootdir, fileset;
 	struct udf_sb_info *sbi;
+	bool lvid_open = false;
 
 	uopt.flags = (1 << UDF_FLAG_USE_AD_IN_ICB) | (1 << UDF_FLAG_STRICT);
 	uopt.uid = INVALID_UID;
@@ -2210,8 +2217,10 @@ static int udf_fill_super(struct super_block *sb, void *options, int silent)
 			 le16_to_cpu(ts.year), ts.month, ts.day,
 			 ts.hour, ts.minute, le16_to_cpu(ts.typeAndTimezone));
 	}
-	if (!(sb->s_flags & MS_RDONLY))
+	if (!(sb->s_flags & MS_RDONLY)) {
 		udf_open_lvid(sb);
+		lvid_open = true;
+	}
 
 	/* Assign the root inode */
 	/* assign inodes by physical block number */
@@ -2242,7 +2251,7 @@ parse_options_failure:
 	if (UDF_QUERY_FLAG(sb, UDF_FLAG_NLS_MAP))
 		unload_nls(sbi->s_nls_map);
 #endif
-	if (!(sb->s_flags & MS_RDONLY))
+	if (lvid_open)
 		udf_close_lvid(sb);
 	brelse(sbi->s_lvid_bh);
 	udf_sb_free_partitions(sb);
diff --git a/kernel/fs/udf/symlink.c b/kernel/fs/udf/symlink.c
index 8dfbc4025..862535b3b 100644
--- a/kernel/fs/udf/symlink.c
+++ b/kernel/fs/udf/symlink.c
@@ -82,6 +82,9 @@ static int udf_pc_to_char(struct super_block *sb, unsigned char *from,
 			comp_len = udf_get_filename(sb, pc->componentIdent,
 						    pc->lengthComponentIdent,
 						    p, tolen);
+			if (comp_len < 0)
+				return comp_len;
+
 			p += comp_len;
 			tolen -= comp_len;
 			if (tolen == 0)
diff --git a/kernel/fs/udf/udf_i.h b/kernel/fs/udf/udf_i.h
index b5cd8ed2a..b1b9a63d8 100644
--- a/kernel/fs/udf/udf_i.h
+++ b/kernel/fs/udf/udf_i.h
@@ -56,7 +56,7 @@ struct udf_inode_info {
 
 static inline struct udf_inode_info *UDF_I(struct inode *inode)
 {
-	return list_entry(inode, struct udf_inode_info, vfs_inode);
+	return container_of(inode, struct udf_inode_info, vfs_inode);
 }
 
 #endif /* _UDF_I_H) */
diff --git a/kernel/fs/udf/unicode.c b/kernel/fs/udf/unicode.c
index b84fee372..e788a05aa 100644
--- a/kernel/fs/udf/unicode.c
+++ b/kernel/fs/udf/unicode.c
@@ -68,21 +68,16 @@ int udf_build_ustr(struct ustr *dest, dstring *ptr, int size)
 /*
  * udf_build_ustr_exact
  */
-static int udf_build_ustr_exact(struct ustr *dest, dstring *ptr, int exactsize)
+static void udf_build_ustr_exact(struct ustr *dest, dstring *ptr, int exactsize)
 {
-	if ((!dest) || (!ptr) || (!exactsize))
-		return -1;
-
 	memset(dest, 0, sizeof(struct ustr));
 	dest->u_cmpID = ptr[0];
 	dest->u_len = exactsize - 1;
 	memcpy(dest->u_name, ptr + 1, exactsize - 1);
-
-	return 0;
 }
 
 /*
- * udf_ocu_to_utf8
+ * udf_CS0toUTF8
  *
  * PURPOSE
  *	Convert OSTA Compressed Unicode to the UTF-8 equivalent.
@@ -94,7 +89,7 @@ static int udf_build_ustr_exact(struct ustr *dest, dstring *ptr, int exactsize)
  * 				both of type "struct ustr *"
  *
  * POST-CONDITIONS
- *	<return>		Zero on success.
+ *	<return>		>= 0 on success.
  *
  * HISTORY
  *	November 12, 1997 - Andrew E. Mileski
@@ -117,7 +112,7 @@ int udf_CS0toUTF8(struct ustr *utf_o, const struct ustr *ocu_i)
 		memset(utf_o, 0, sizeof(struct ustr));
 		pr_err("unknown compression code (%d) stri=%s\n",
 		       cmp_id, ocu_i->u_name);
-		return 0;
+		return -EINVAL;
 	}
 
 	ocu = ocu_i->u_name;
@@ -133,11 +128,15 @@ int udf_CS0toUTF8(struct ustr *utf_o, const struct ustr *ocu_i)
 		if (c < 0x80U)
 			utf_o->u_name[utf_o->u_len++] = (uint8_t)c;
 		else if (c < 0x800U) {
+			if (utf_o->u_len > (UDF_NAME_LEN - 4))
+				break;
 			utf_o->u_name[utf_o->u_len++] =
 						(uint8_t)(0xc0 | (c >> 6));
 			utf_o->u_name[utf_o->u_len++] =
 						(uint8_t)(0x80 | (c & 0x3f));
 		} else {
+			if (utf_o->u_len > (UDF_NAME_LEN - 5))
+				break;
 			utf_o->u_name[utf_o->u_len++] =
 						(uint8_t)(0xe0 | (c >> 12));
 			utf_o->u_name[utf_o->u_len++] =
@@ -154,7 +153,7 @@ int udf_CS0toUTF8(struct ustr *utf_o, const struct ustr *ocu_i)
 
 /*
  *
- * udf_utf8_to_ocu
+ * udf_UTF8toCS0
  *
  * PURPOSE
  *	Convert UTF-8 to the OSTA Compressed Unicode equivalent.
@@ -178,17 +177,22 @@ int udf_CS0toUTF8(struct ustr *utf_o, const struct ustr *ocu_i)
 static int udf_UTF8toCS0(dstring *ocu, struct ustr *utf, int length)
 {
 	unsigned c, i, max_val, utf_char;
-	int utf_cnt, u_len;
+	int utf_cnt, u_len, u_ch;
 
 	memset(ocu, 0, sizeof(dstring) * length);
 	ocu[0] = 8;
 	max_val = 0xffU;
+	u_ch = 1;
 
 try_again:
 	u_len = 0U;
 	utf_char = 0U;
 	utf_cnt = 0U;
 	for (i = 0U; i < utf->u_len; i++) {
+		/* Name didn't fit? */
+		if (u_len + 1 + u_ch >= length)
+			return 0;
+
 		c = (uint8_t)utf->u_name[i];
 
 		/* Complete a multi-byte UTF-8 character */
@@ -230,6 +234,7 @@ try_again:
 			if (max_val == 0xffU) {
 				max_val = 0xffffU;
 				ocu[0] = (uint8_t)0x10U;
+				u_ch = 2;
 				goto try_again;
 			}
 			goto error_out;
@@ -270,7 +275,7 @@ static int udf_CS0toNLS(struct nls_table *nls, struct ustr *utf_o,
 		memset(utf_o, 0, sizeof(struct ustr));
 		pr_err("unknown compression code (%d) stri=%s\n",
 		       cmp_id, ocu_i->u_name);
-		return 0;
+		return -EINVAL;
 	}
 
 	ocu = ocu_i->u_name;
@@ -282,7 +287,7 @@ static int udf_CS0toNLS(struct nls_table *nls, struct ustr *utf_o,
 			c = (c << 8) | ocu[i++];
 
 		len = nls->uni2char(c, &utf_o->u_name[utf_o->u_len],
-				    UDF_NAME_LEN - utf_o->u_len);
+				    UDF_NAME_LEN - 2 - utf_o->u_len);
 		/* Valid character? */
 		if (len >= 0)
 			utf_o->u_len += len;
@@ -300,15 +305,19 @@ static int udf_NLStoCS0(struct nls_table *nls, dstring *ocu, struct ustr *uni,
 	int len;
 	unsigned i, max_val;
 	uint16_t uni_char;
-	int u_len;
+	int u_len, u_ch;
 
 	memset(ocu, 0, sizeof(dstring) * length);
 	ocu[0] = 8;
 	max_val = 0xffU;
+	u_ch = 1;
 
 try_again:
 	u_len = 0U;
 	for (i = 0U; i < uni->u_len; i++) {
+		/* Name didn't fit? */
+		if (u_len + 1 + u_ch >= length)
+			return 0;
 		len = nls->char2uni(&uni->u_name[i], uni->u_len - i, &uni_char);
 		if (!len)
 			continue;
@@ -321,6 +330,7 @@ try_again:
 		if (uni_char > max_val) {
 			max_val = 0xffffU;
 			ocu[0] = (uint8_t)0x10U;
+			u_ch = 2;
 			goto try_again;
 		}
 
@@ -338,43 +348,51 @@ int udf_get_filename(struct super_block *sb, uint8_t *sname, int slen,
 		     uint8_t *dname, int dlen)
 {
 	struct ustr *filename, *unifilename;
-	int len = 0;
+	int ret;
+
+	if (!slen)
+		return -EIO;
 
 	filename = kmalloc(sizeof(struct ustr), GFP_NOFS);
 	if (!filename)
-		return 0;
+		return -ENOMEM;
 
 	unifilename = kmalloc(sizeof(struct ustr), GFP_NOFS);
-	if (!unifilename)
+	if (!unifilename) {
+		ret = -ENOMEM;
 		goto out1;
+	}
 
-	if (udf_build_ustr_exact(unifilename, sname, slen))
-		goto out2;
-
+	udf_build_ustr_exact(unifilename, sname, slen);
 	if (UDF_QUERY_FLAG(sb, UDF_FLAG_UTF8)) {
-		if (!udf_CS0toUTF8(filename, unifilename)) {
+		ret = udf_CS0toUTF8(filename, unifilename);
+		if (ret < 0) {
 			udf_debug("Failed in udf_get_filename: sname = %s\n",
 				  sname);
 			goto out2;
 		}
 	} else if (UDF_QUERY_FLAG(sb, UDF_FLAG_NLS_MAP)) {
-		if (!udf_CS0toNLS(UDF_SB(sb)->s_nls_map, filename,
-				  unifilename)) {
+		ret = udf_CS0toNLS(UDF_SB(sb)->s_nls_map, filename,
+				   unifilename);
+		if (ret < 0) {
 			udf_debug("Failed in udf_get_filename: sname = %s\n",
 				  sname);
 			goto out2;
 		}
 	} else
-		goto out2;
+		BUG();
 
-	len = udf_translate_to_linux(dname, dlen,
+	ret = udf_translate_to_linux(dname, dlen,
 				     filename->u_name, filename->u_len,
 				     unifilename->u_name, unifilename->u_len);
+	/* Zero length filename isn't valid... */
+	if (ret == 0)
+		ret = -EINVAL;
 out2:
 	kfree(unifilename);
 out1:
 	kfree(filename);
-	return len;
+	return ret;
 }
 
 int udf_put_filename(struct super_block *sb, const uint8_t *sname,