udf: improve error management in udf_CS0toUTF8()

udf_CS0toUTF8() now returns -EINVAL on error.
udf_load_pvoldesc() and udf_get_filename() do the same.

Suggested-by: Jan Kara <jack@suse.cz>
Signed-off-by: Fabian Frederick <fabf@skynet.be>
Signed-off-by: Jan Kara <jack@suse.cz>

2 files changed, 18 insertions, 12 deletions

diff --git a/fs/udf/super.c b/fs/udf/super.c
index 6299f341967b..c6a8f5f79443 100644
--- a/fs/udf/super.c
+++ b/fs/udf/super.c
@@ -927,17 +927,22 @@ 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))
-                if (udf_CS0toUTF8(outstr, instr))
-                        udf_debug("volSetIdent[] = '%s'\n", outstr->u_name);
+                ret = udf_CS0toUTF8(outstr, instr);
+                if (ret < 0)
+                        goto out_bh;
+
+                udf_debug("volSetIdent[] = '%s'\n", outstr->u_name);
 
         ret = 0;
 out_bh:
diff --git a/fs/udf/unicode.c b/fs/udf/unicode.c
index 41c3bef1d226..35cc9477b066 100644
--- a/fs/udf/unicode.c
+++ b/fs/udf/unicode.c
@@ -89,7 +89,7 @@ static void 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
@@ -112,7 +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;
@@ -350,7 +350,8 @@ int udf_get_filename(struct super_block *sb, uint8_t *sname, int slen,
 
         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;