diff options
Diffstat (limited to 'fs/udf/super.c')
-rw-r--r-- | fs/udf/super.c | 109 |
1 files changed, 76 insertions, 33 deletions
diff --git a/fs/udf/super.c b/fs/udf/super.c index 839a2bad7f4..3306b9f69be 100644 --- a/fs/udf/super.c +++ b/fs/udf/super.c @@ -76,6 +76,9 @@ #define UDF_DEFAULT_BLOCKSIZE 2048 +#define VSD_FIRST_SECTOR_OFFSET 32768 +#define VSD_MAX_SECTOR_OFFSET 0x800000 + enum { UDF_MAX_LINKS = 0xffff }; /* These are the "meat" - everything else is stuffing */ @@ -94,13 +97,25 @@ static unsigned int udf_count_free(struct super_block *); static int udf_statfs(struct dentry *, struct kstatfs *); static int udf_show_options(struct seq_file *, struct dentry *); -struct logicalVolIntegrityDescImpUse *udf_sb_lvidiu(struct udf_sb_info *sbi) +struct logicalVolIntegrityDescImpUse *udf_sb_lvidiu(struct super_block *sb) { - struct logicalVolIntegrityDesc *lvid = - (struct logicalVolIntegrityDesc *)sbi->s_lvid_bh->b_data; - __u32 number_of_partitions = le32_to_cpu(lvid->numOfPartitions); - __u32 offset = number_of_partitions * 2 * - sizeof(uint32_t)/sizeof(uint8_t); + struct logicalVolIntegrityDesc *lvid; + unsigned int partnum; + unsigned int offset; + + if (!UDF_SB(sb)->s_lvid_bh) + return NULL; + lvid = (struct logicalVolIntegrityDesc *)UDF_SB(sb)->s_lvid_bh->b_data; + partnum = le32_to_cpu(lvid->numOfPartitions); + if ((sb->s_blocksize - sizeof(struct logicalVolIntegrityDescImpUse) - + offsetof(struct logicalVolIntegrityDesc, impUse)) / + (2 * sizeof(uint32_t)) < partnum) { + udf_err(sb, "Logical volume integrity descriptor corrupted " + "(numOfPartitions = %u)!\n", partnum); + return NULL; + } + /* The offset is to skip freeSpaceTable and sizeTable arrays */ + offset = partnum * 2 * sizeof(uint32_t); return (struct logicalVolIntegrityDescImpUse *)&(lvid->impUse[offset]); } @@ -629,9 +644,10 @@ static int udf_remount_fs(struct super_block *sb, int *flags, char *options) struct udf_options uopt; struct udf_sb_info *sbi = UDF_SB(sb); int error = 0; + struct logicalVolIntegrityDescImpUse *lvidiu = udf_sb_lvidiu(sb); - if (sbi->s_lvid_bh) { - int write_rev = le16_to_cpu(udf_sb_lvidiu(sbi)->minUDFWriteRev); + if (lvidiu) { + int write_rev = le16_to_cpu(lvidiu->minUDFWriteRev); if (write_rev > UDF_MAX_WRITE_VERSION && !(*flags & MS_RDONLY)) return -EACCES; } @@ -672,7 +688,7 @@ out_unlock: static loff_t udf_check_vsd(struct super_block *sb) { struct volStructDesc *vsd = NULL; - loff_t sector = 32768; + loff_t sector = VSD_FIRST_SECTOR_OFFSET; int sectorsize; struct buffer_head *bh = NULL; int nsr02 = 0; @@ -690,8 +706,18 @@ static loff_t udf_check_vsd(struct super_block *sb) udf_debug("Starting at sector %u (%ld byte sectors)\n", (unsigned int)(sector >> sb->s_blocksize_bits), sb->s_blocksize); - /* Process the sequence (if applicable) */ - for (; !nsr02 && !nsr03; sector += sectorsize) { + /* Process the sequence (if applicable). The hard limit on the sector + * offset is arbitrary, hopefully large enough so that all valid UDF + * filesystems will be recognised. There is no mention of an upper + * bound to the size of the volume recognition area in the standard. + * The limit will prevent the code to read all the sectors of a + * specially crafted image (like a bluray disc full of CD001 sectors), + * potentially causing minutes or even hours of uninterruptible I/O + * activity. This actually happened with uninitialised SSD partitions + * (all 0xFF) before the check for the limit and all valid IDs were + * added */ + for (; !nsr02 && !nsr03 && sector < VSD_MAX_SECTOR_OFFSET; + sector += sectorsize) { /* Read a block */ bh = udf_tread(sb, sector >> sb->s_blocksize_bits); if (!bh) @@ -701,10 +727,7 @@ static loff_t udf_check_vsd(struct super_block *sb) vsd = (struct volStructDesc *)(bh->b_data + (sector & (sb->s_blocksize - 1))); - if (vsd->stdIdent[0] == 0) { - brelse(bh); - break; - } else if (!strncmp(vsd->stdIdent, VSD_STD_ID_CD001, + if (!strncmp(vsd->stdIdent, VSD_STD_ID_CD001, VSD_STD_ID_LEN)) { switch (vsd->structType) { case 0: @@ -740,6 +763,17 @@ static loff_t udf_check_vsd(struct super_block *sb) else if (!strncmp(vsd->stdIdent, VSD_STD_ID_NSR03, VSD_STD_ID_LEN)) nsr03 = sector; + else if (!strncmp(vsd->stdIdent, VSD_STD_ID_BOOT2, + VSD_STD_ID_LEN)) + ; /* nothing */ + else if (!strncmp(vsd->stdIdent, VSD_STD_ID_CDW02, + VSD_STD_ID_LEN)) + ; /* nothing */ + else { + /* invalid id : end of volume recognition area */ + brelse(bh); + break; + } brelse(bh); } @@ -747,7 +781,8 @@ static loff_t udf_check_vsd(struct super_block *sb) return nsr03; else if (nsr02) return nsr02; - else if (sector - (sbi->s_session << sb->s_blocksize_bits) == 32768) + else if (!bh && sector - (sbi->s_session << sb->s_blocksize_bits) == + VSD_FIRST_SECTOR_OFFSET) return -1; else return 0; @@ -1257,6 +1292,9 @@ static int udf_load_partdesc(struct super_block *sb, sector_t block) * PHYSICAL partitions are already set up */ type1_idx = i; +#ifdef UDFFS_DEBUG + map = NULL; /* supress 'maybe used uninitialized' warning */ +#endif for (i = 0; i < sbi->s_partitions; i++) { map = &sbi->s_partmaps[i]; @@ -1878,7 +1916,9 @@ static int udf_load_vrs(struct super_block *sb, struct udf_options *uopt, return 0; } if (nsr_off == -1) - udf_debug("Failed to read byte 32768. Assuming open disc. Skipping validity check\n"); + udf_debug("Failed to read sector at offset %d. " + "Assuming open disc. Skipping validity " + "check\n", VSD_FIRST_SECTOR_OFFSET); if (!sbi->s_last_block) sbi->s_last_block = udf_get_last_block(sb); } else { @@ -1905,11 +1945,12 @@ static void udf_open_lvid(struct super_block *sb) if (!bh) return; - - mutex_lock(&sbi->s_alloc_mutex); lvid = (struct logicalVolIntegrityDesc *)bh->b_data; - lvidiu = udf_sb_lvidiu(sbi); + lvidiu = udf_sb_lvidiu(sb); + if (!lvidiu) + return; + mutex_lock(&sbi->s_alloc_mutex); lvidiu->impIdent.identSuffix[0] = UDF_OS_CLASS_UNIX; lvidiu->impIdent.identSuffix[1] = UDF_OS_ID_LINUX; udf_time_to_disk_stamp(&lvid->recordingDateAndTime, @@ -1937,10 +1978,12 @@ static void udf_close_lvid(struct super_block *sb) if (!bh) return; + lvid = (struct logicalVolIntegrityDesc *)bh->b_data; + lvidiu = udf_sb_lvidiu(sb); + if (!lvidiu) + return; mutex_lock(&sbi->s_alloc_mutex); - lvid = (struct logicalVolIntegrityDesc *)bh->b_data; - lvidiu = udf_sb_lvidiu(sbi); lvidiu->impIdent.identSuffix[0] = UDF_OS_CLASS_UNIX; lvidiu->impIdent.identSuffix[1] = UDF_OS_ID_LINUX; udf_time_to_disk_stamp(&lvid->recordingDateAndTime, CURRENT_TIME); @@ -2093,15 +2136,19 @@ static int udf_fill_super(struct super_block *sb, void *options, int silent) if (sbi->s_lvid_bh) { struct logicalVolIntegrityDescImpUse *lvidiu = - udf_sb_lvidiu(sbi); - uint16_t minUDFReadRev = le16_to_cpu(lvidiu->minUDFReadRev); - uint16_t minUDFWriteRev = le16_to_cpu(lvidiu->minUDFWriteRev); - /* uint16_t maxUDFWriteRev = - le16_to_cpu(lvidiu->maxUDFWriteRev); */ + udf_sb_lvidiu(sb); + uint16_t minUDFReadRev; + uint16_t minUDFWriteRev; + if (!lvidiu) { + ret = -EINVAL; + goto error_out; + } + minUDFReadRev = le16_to_cpu(lvidiu->minUDFReadRev); + minUDFWriteRev = le16_to_cpu(lvidiu->minUDFWriteRev); if (minUDFReadRev > UDF_MAX_READ_VERSION) { udf_err(sb, "minUDFReadRev=%x (max is %x)\n", - le16_to_cpu(lvidiu->minUDFReadRev), + minUDFReadRev, UDF_MAX_READ_VERSION); ret = -EINVAL; goto error_out; @@ -2265,11 +2312,7 @@ static int udf_statfs(struct dentry *dentry, struct kstatfs *buf) struct logicalVolIntegrityDescImpUse *lvidiu; u64 id = huge_encode_dev(sb->s_bdev->bd_dev); - if (sbi->s_lvid_bh != NULL) - lvidiu = udf_sb_lvidiu(sbi); - else - lvidiu = NULL; - + lvidiu = udf_sb_lvidiu(sb); buf->f_type = UDF_SUPER_MAGIC; buf->f_bsize = sb->s_blocksize; buf->f_blocks = sbi->s_partmaps[sbi->s_partition].s_partition_len; |