1 files changed, 33 insertions, 18 deletions

diff --git a/fs/udf/super.c b/fs/udf/super.c
index e3d684ea3203..ffd8038ff728 100644
--- a/fs/udf/super.c
+++ b/fs/udf/super.c
@@ -1474,6 +1474,17 @@ static int udf_load_logicalvol(struct super_block *sb, sector_t block,
         if (lvd->integritySeqExt.extLength)
                 udf_load_logicalvolint(sb, leea_to_cpu(lvd->integritySeqExt));
         ret = 0;
+
+        if (!sbi->s_lvid_bh) {
+                /* We can't generate unique IDs without a valid LVID */
+                if (sb_rdonly(sb)) {
+                        UDF_SET_FLAG(sb, UDF_FLAG_RW_INCOMPAT);
+                } else {
+                        udf_warn(sb, "Damaged or missing LVID, forcing "
+                                     "readonly mount\n");
+                        ret = -EACCES;
+                }
+        }
 out_bh:
         brelse(bh);
         return ret;
@@ -1943,13 +1954,24 @@ static int udf_load_vrs(struct super_block *sb, struct udf_options *uopt,
         return 0;
 }
 
+static void udf_finalize_lvid(struct logicalVolIntegrityDesc *lvid)
+{
+        struct timespec64 ts;
+
+        ktime_get_real_ts64(&ts);
+        udf_time_to_disk_stamp(&lvid->recordingDateAndTime, ts);
+        lvid->descTag.descCRC = cpu_to_le16(
+                crc_itu_t(0, (char *)lvid + sizeof(struct tag),
+                        le16_to_cpu(lvid->descTag.descCRCLength)));
+        lvid->descTag.tagChecksum = udf_tag_checksum(&lvid->descTag);
+}
+
 static void udf_open_lvid(struct super_block *sb)
 {
         struct udf_sb_info *sbi = UDF_SB(sb);
         struct buffer_head *bh = sbi->s_lvid_bh;
         struct logicalVolIntegrityDesc *lvid;
         struct logicalVolIntegrityDescImpUse *lvidiu;
-        struct timespec64 ts;
 
         if (!bh)
                 return;
@@ -1961,18 +1983,12 @@ static void udf_open_lvid(struct super_block *sb)
         mutex_lock(&sbi->s_alloc_mutex);
         lvidiu->impIdent.identSuffix[0] = UDF_OS_CLASS_UNIX;
         lvidiu->impIdent.identSuffix[1] = UDF_OS_ID_LINUX;
-        ktime_get_real_ts64(&ts);
-        udf_time_to_disk_stamp(&lvid->recordingDateAndTime, ts);
         if (le32_to_cpu(lvid->integrityType) == LVID_INTEGRITY_TYPE_CLOSE)
                 lvid->integrityType = cpu_to_le32(LVID_INTEGRITY_TYPE_OPEN);
         else
                 UDF_SET_FLAG(sb, UDF_FLAG_INCONSISTENT);
 
-        lvid->descTag.descCRC = cpu_to_le16(
-                crc_itu_t(0, (char *)lvid + sizeof(struct tag),
-                        le16_to_cpu(lvid->descTag.descCRCLength)));
-
-        lvid->descTag.tagChecksum = udf_tag_checksum(&lvid->descTag);
+        udf_finalize_lvid(lvid);
         mark_buffer_dirty(bh);
         sbi->s_lvid_dirty = 0;
         mutex_unlock(&sbi->s_alloc_mutex);
@@ -1986,7 +2002,6 @@ static void udf_close_lvid(struct super_block *sb)
         struct buffer_head *bh = sbi->s_lvid_bh;
         struct logicalVolIntegrityDesc *lvid;
         struct logicalVolIntegrityDescImpUse *lvidiu;
-        struct timespec64 ts;
 
         if (!bh)
                 return;
@@ -1998,8 +2013,6 @@ static void udf_close_lvid(struct super_block *sb)
         mutex_lock(&sbi->s_alloc_mutex);
         lvidiu->impIdent.identSuffix[0] = UDF_OS_CLASS_UNIX;
         lvidiu->impIdent.identSuffix[1] = UDF_OS_ID_LINUX;
-        ktime_get_real_ts64(&ts);
-        udf_time_to_disk_stamp(&lvid->recordingDateAndTime, ts);
         if (UDF_MAX_WRITE_VERSION > le16_to_cpu(lvidiu->maxUDFWriteRev))
                 lvidiu->maxUDFWriteRev = cpu_to_le16(UDF_MAX_WRITE_VERSION);
         if (sbi->s_udfrev > le16_to_cpu(lvidiu->minUDFReadRev))
@@ -2009,17 +2022,13 @@ static void udf_close_lvid(struct super_block *sb)
         if (!UDF_QUERY_FLAG(sb, UDF_FLAG_INCONSISTENT))
                 lvid->integrityType = cpu_to_le32(LVID_INTEGRITY_TYPE_CLOSE);
 
-        lvid->descTag.descCRC = cpu_to_le16(
-                        crc_itu_t(0, (char *)lvid + sizeof(struct tag),
-                                le16_to_cpu(lvid->descTag.descCRCLength)));
-
-        lvid->descTag.tagChecksum = udf_tag_checksum(&lvid->descTag);
         /*
          * We set buffer uptodate unconditionally here to avoid spurious
          * warnings from mark_buffer_dirty() when previous EIO has marked
          * the buffer as !uptodate
          */
         set_buffer_uptodate(bh);
+        udf_finalize_lvid(lvid);
         mark_buffer_dirty(bh);
         sbi->s_lvid_dirty = 0;
         mutex_unlock(&sbi->s_alloc_mutex);
@@ -2048,8 +2057,8 @@ u64 lvid_get_unique_id(struct super_block *sb)
         if (!(++uniqueID & 0xFFFFFFFF))
                 uniqueID += 16;
         lvhd->uniqueID = cpu_to_le64(uniqueID);
+        udf_updated_lvid(sb);
         mutex_unlock(&sbi->s_alloc_mutex);
-        mark_buffer_dirty(bh);
 
         return ret;
 }
@@ -2320,11 +2329,17 @@ static int udf_sync_fs(struct super_block *sb, int wait)
 
         mutex_lock(&sbi->s_alloc_mutex);
         if (sbi->s_lvid_dirty) {
+                struct buffer_head *bh = sbi->s_lvid_bh;
+                struct logicalVolIntegrityDesc *lvid;
+
+                lvid = (struct logicalVolIntegrityDesc *)bh->b_data;
+                udf_finalize_lvid(lvid);
+
                 /*
                  * Blockdevice will be synced later so we don't have to submit
                  * the buffer for IO
                  */
-                mark_buffer_dirty(sbi->s_lvid_bh);
+                mark_buffer_dirty(bh);
                 sbi->s_lvid_dirty = 0;
         }
         mutex_unlock(&sbi->s_alloc_mutex);