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Diffstat (limited to 'fs/udf/super.c')
-rw-r--r--fs/udf/super.c109
1 files changed, 76 insertions, 33 deletions
diff --git a/fs/udf/super.c b/fs/udf/super.c
index 839a2bad7f45..3306b9f69bed 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;
generated by cgit v1.2.3 (git 2.39.0) at 2024-12-03 13:48:42 +0300