return 0;
}
+/*
+ * Maximum length of linked list formed by ICB hierarchy. The chosen number is
+ * arbitrary - just that we hopefully don't limit any real use of rewritten
+ * inode on write-once media but avoid looping for too long on corrupted media.
+ */
+#define UDF_MAX_ICB_NESTING 1024
+
static void __udf_read_inode(struct inode *inode)
{
struct buffer_head *bh = NULL;
struct fileEntry *fe;
uint16_t ident;
struct udf_inode_info *iinfo = UDF_I(inode);
+ unsigned int indirections = 0;
+reread:
/*
* Set defaults, but the inode is still incomplete!
* Note: get_new_inode() sets the following on a new inode:
ibh = udf_read_ptagged(inode->i_sb, &iinfo->i_location, 1,
&ident);
if (ident == TAG_IDENT_IE && ibh) {
- struct buffer_head *nbh = NULL;
struct kernel_lb_addr loc;
struct indirectEntry *ie;
ie = (struct indirectEntry *)ibh->b_data;
loc = lelb_to_cpu(ie->indirectICB.extLocation);
- if (ie->indirectICB.extLength &&
- (nbh = udf_read_ptagged(inode->i_sb, &loc, 0,
- &ident))) {
- if (ident == TAG_IDENT_FE ||
- ident == TAG_IDENT_EFE) {
- memcpy(&iinfo->i_location,
- &loc,
- sizeof(struct kernel_lb_addr));
- brelse(bh);
- brelse(ibh);
- brelse(nbh);
- __udf_read_inode(inode);
+ if (ie->indirectICB.extLength) {
+ brelse(bh);
+ brelse(ibh);
+ memcpy(&iinfo->i_location, &loc,
+ sizeof(struct kernel_lb_addr));
+ if (++indirections > UDF_MAX_ICB_NESTING) {
+ udf_err(inode->i_sb,
+ "too many ICBs in ICB hierarchy"
+ " (max %d supported)\n",
+ UDF_MAX_ICB_NESTING);
+ make_bad_inode(inode);
return;
}
- brelse(nbh);
+ goto reread;
}
}
brelse(ibh);
struct udf_sb_info *sbi = UDF_SB(inode->i_sb);
struct udf_inode_info *iinfo = UDF_I(inode);
unsigned int link_count;
+ int bs = inode->i_sb->s_blocksize;
fe = (struct fileEntry *)bh->b_data;
efe = (struct extendedFileEntry *)bh->b_data;
if (fe->descTag.tagIdent == cpu_to_le16(TAG_IDENT_EFE)) {
iinfo->i_efe = 1;
iinfo->i_use = 0;
- if (udf_alloc_i_data(inode, inode->i_sb->s_blocksize -
+ if (udf_alloc_i_data(inode, bs -
sizeof(struct extendedFileEntry))) {
make_bad_inode(inode);
return;
}
memcpy(iinfo->i_ext.i_data,
bh->b_data + sizeof(struct extendedFileEntry),
- inode->i_sb->s_blocksize -
- sizeof(struct extendedFileEntry));
+ bs - sizeof(struct extendedFileEntry));
} else if (fe->descTag.tagIdent == cpu_to_le16(TAG_IDENT_FE)) {
iinfo->i_efe = 0;
iinfo->i_use = 0;
- if (udf_alloc_i_data(inode, inode->i_sb->s_blocksize -
- sizeof(struct fileEntry))) {
+ if (udf_alloc_i_data(inode, bs - sizeof(struct fileEntry))) {
make_bad_inode(inode);
return;
}
memcpy(iinfo->i_ext.i_data,
bh->b_data + sizeof(struct fileEntry),
- inode->i_sb->s_blocksize - sizeof(struct fileEntry));
+ bs - sizeof(struct fileEntry));
} else if (fe->descTag.tagIdent == cpu_to_le16(TAG_IDENT_USE)) {
iinfo->i_efe = 0;
iinfo->i_use = 1;
iinfo->i_lenAlloc = le32_to_cpu(
((struct unallocSpaceEntry *)bh->b_data)->
lengthAllocDescs);
- if (udf_alloc_i_data(inode, inode->i_sb->s_blocksize -
+ if (udf_alloc_i_data(inode, bs -
sizeof(struct unallocSpaceEntry))) {
make_bad_inode(inode);
return;
}
memcpy(iinfo->i_ext.i_data,
bh->b_data + sizeof(struct unallocSpaceEntry),
- inode->i_sb->s_blocksize -
- sizeof(struct unallocSpaceEntry));
+ bs - sizeof(struct unallocSpaceEntry));
return;
}
iinfo->i_lenEAttr;
}
+ /*
+ * Sanity check length of allocation descriptors and extended attrs to
+ * avoid integer overflows
+ */
+ if (iinfo->i_lenEAttr > bs || iinfo->i_lenAlloc > bs) {
+ make_bad_inode(inode);
+ return;
+ }
+ /* Now do exact checks */
+ if (udf_file_entry_alloc_offset(inode) + iinfo->i_lenAlloc > bs) {
+ make_bad_inode(inode);
+ return;
+ }
+ /* Sanity checks for files in ICB so that we don't get confused later */
+ if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_IN_ICB) {
+ /*
+ * For file in ICB data is stored in allocation descriptor
+ * so sizes should match
+ */
+ if (iinfo->i_lenAlloc != inode->i_size) {
+ make_bad_inode(inode);
+ return;
+ }
+ /* File in ICB has to fit in there... */
+ if (inode->i_size > bs - udf_file_entry_alloc_offset(inode)) {
+ make_bad_inode(inode);
+ return;
+ }
+ }
+
switch (fe->icbTag.fileType) {
case ICBTAG_FILE_TYPE_DIRECTORY:
inode->i_op = &udf_dir_inode_operations;
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);
git.openpandora.org / pandora-kernel.git / blobdiff