mirror of
https://mirrors.bfsu.edu.cn/git/linux.git
synced 2024-11-16 08:44:21 +08:00
410dd3cf4c
We did not check relocated directory in any way when processing Rock Ridge 'CL' tag. Thus a corrupted isofs image can possibly have a CL entry pointing to another CL entry leading to possibly unbounded recursion in kernel code and thus stack overflow or deadlocks (if there is a loop created from CL entries). Fix the problem by not allowing CL entry to point to a directory entry with CL entry (such use makes no good sense anyway) and by checking whether CL entry doesn't point to itself. CC: stable@vger.kernel.org Reported-by: Chris Evans <cevans@google.com> Signed-off-by: Jan Kara <jack@suse.cz>
199 lines
6.3 KiB
C
199 lines
6.3 KiB
C
#include <linux/fs.h>
|
|
#include <linux/buffer_head.h>
|
|
#include <linux/exportfs.h>
|
|
#include <linux/iso_fs.h>
|
|
#include <asm/unaligned.h>
|
|
|
|
enum isofs_file_format {
|
|
isofs_file_normal = 0,
|
|
isofs_file_sparse = 1,
|
|
isofs_file_compressed = 2,
|
|
};
|
|
|
|
/*
|
|
* iso fs inode data in memory
|
|
*/
|
|
struct iso_inode_info {
|
|
unsigned long i_iget5_block;
|
|
unsigned long i_iget5_offset;
|
|
unsigned int i_first_extent;
|
|
unsigned char i_file_format;
|
|
unsigned char i_format_parm[3];
|
|
unsigned long i_next_section_block;
|
|
unsigned long i_next_section_offset;
|
|
off_t i_section_size;
|
|
struct inode vfs_inode;
|
|
};
|
|
|
|
/*
|
|
* iso9660 super-block data in memory
|
|
*/
|
|
struct isofs_sb_info {
|
|
unsigned long s_ninodes;
|
|
unsigned long s_nzones;
|
|
unsigned long s_firstdatazone;
|
|
unsigned long s_log_zone_size;
|
|
unsigned long s_max_size;
|
|
|
|
int s_rock_offset; /* offset of SUSP fields within SU area */
|
|
unsigned char s_joliet_level;
|
|
unsigned char s_mapping;
|
|
unsigned int s_high_sierra:1;
|
|
unsigned int s_rock:2;
|
|
unsigned int s_utf8:1;
|
|
unsigned int s_cruft:1; /* Broken disks with high byte of length
|
|
* containing junk */
|
|
unsigned int s_nocompress:1;
|
|
unsigned int s_hide:1;
|
|
unsigned int s_showassoc:1;
|
|
unsigned int s_overriderockperm:1;
|
|
unsigned int s_uid_set:1;
|
|
unsigned int s_gid_set:1;
|
|
|
|
umode_t s_fmode;
|
|
umode_t s_dmode;
|
|
kgid_t s_gid;
|
|
kuid_t s_uid;
|
|
struct nls_table *s_nls_iocharset; /* Native language support table */
|
|
};
|
|
|
|
#define ISOFS_INVALID_MODE ((umode_t) -1)
|
|
|
|
static inline struct isofs_sb_info *ISOFS_SB(struct super_block *sb)
|
|
{
|
|
return sb->s_fs_info;
|
|
}
|
|
|
|
static inline struct iso_inode_info *ISOFS_I(struct inode *inode)
|
|
{
|
|
return container_of(inode, struct iso_inode_info, vfs_inode);
|
|
}
|
|
|
|
static inline int isonum_711(char *p)
|
|
{
|
|
return *(u8 *)p;
|
|
}
|
|
static inline int isonum_712(char *p)
|
|
{
|
|
return *(s8 *)p;
|
|
}
|
|
static inline unsigned int isonum_721(char *p)
|
|
{
|
|
return get_unaligned_le16(p);
|
|
}
|
|
static inline unsigned int isonum_722(char *p)
|
|
{
|
|
return get_unaligned_be16(p);
|
|
}
|
|
static inline unsigned int isonum_723(char *p)
|
|
{
|
|
/* Ignore bigendian datum due to broken mastering programs */
|
|
return get_unaligned_le16(p);
|
|
}
|
|
static inline unsigned int isonum_731(char *p)
|
|
{
|
|
return get_unaligned_le32(p);
|
|
}
|
|
static inline unsigned int isonum_732(char *p)
|
|
{
|
|
return get_unaligned_be32(p);
|
|
}
|
|
static inline unsigned int isonum_733(char *p)
|
|
{
|
|
/* Ignore bigendian datum due to broken mastering programs */
|
|
return get_unaligned_le32(p);
|
|
}
|
|
extern int iso_date(char *, int);
|
|
|
|
struct inode; /* To make gcc happy */
|
|
|
|
extern int parse_rock_ridge_inode(struct iso_directory_record *, struct inode *, int relocated);
|
|
extern int get_rock_ridge_filename(struct iso_directory_record *, char *, struct inode *);
|
|
extern int isofs_name_translate(struct iso_directory_record *, char *, struct inode *);
|
|
|
|
int get_joliet_filename(struct iso_directory_record *, unsigned char *, struct inode *);
|
|
int get_acorn_filename(struct iso_directory_record *, char *, struct inode *);
|
|
|
|
extern struct dentry *isofs_lookup(struct inode *, struct dentry *, unsigned int flags);
|
|
extern struct buffer_head *isofs_bread(struct inode *, sector_t);
|
|
extern int isofs_get_blocks(struct inode *, sector_t, struct buffer_head **, unsigned long);
|
|
|
|
struct inode *__isofs_iget(struct super_block *sb,
|
|
unsigned long block,
|
|
unsigned long offset,
|
|
int relocated);
|
|
|
|
static inline struct inode *isofs_iget(struct super_block *sb,
|
|
unsigned long block,
|
|
unsigned long offset)
|
|
{
|
|
return __isofs_iget(sb, block, offset, 0);
|
|
}
|
|
|
|
static inline struct inode *isofs_iget_reloc(struct super_block *sb,
|
|
unsigned long block,
|
|
unsigned long offset)
|
|
{
|
|
return __isofs_iget(sb, block, offset, 1);
|
|
}
|
|
|
|
/* Because the inode number is no longer relevant to finding the
|
|
* underlying meta-data for an inode, we are free to choose a more
|
|
* convenient 32-bit number as the inode number. The inode numbering
|
|
* scheme was recommended by Sergey Vlasov and Eric Lammerts. */
|
|
static inline unsigned long isofs_get_ino(unsigned long block,
|
|
unsigned long offset,
|
|
unsigned long bufbits)
|
|
{
|
|
return (block << (bufbits - 5)) | (offset >> 5);
|
|
}
|
|
|
|
/* Every directory can have many redundant directory entries scattered
|
|
* throughout the directory tree. First there is the directory entry
|
|
* with the name of the directory stored in the parent directory.
|
|
* Then, there is the "." directory entry stored in the directory
|
|
* itself. Finally, there are possibly many ".." directory entries
|
|
* stored in all the subdirectories.
|
|
*
|
|
* In order for the NFS get_parent() method to work and for the
|
|
* general consistency of the dcache, we need to make sure the
|
|
* "i_iget5_block" and "i_iget5_offset" all point to exactly one of
|
|
* the many redundant entries for each directory. We normalize the
|
|
* block and offset by always making them point to the "." directory.
|
|
*
|
|
* Notice that we do not use the entry for the directory with the name
|
|
* that is located in the parent directory. Even though choosing this
|
|
* first directory is more natural, it is much easier to find the "."
|
|
* entry in the NFS get_parent() method because it is implicitly
|
|
* encoded in the "extent + ext_attr_length" fields of _all_ the
|
|
* redundant entries for the directory. Thus, it can always be
|
|
* reached regardless of which directory entry you have in hand.
|
|
*
|
|
* This works because the "." entry is simply the first directory
|
|
* record when you start reading the file that holds all the directory
|
|
* records, and this file starts at "extent + ext_attr_length" blocks.
|
|
* Because the "." entry is always the first entry listed in the
|
|
* directories file, the normalized "offset" value is always 0.
|
|
*
|
|
* You should pass the directory entry in "de". On return, "block"
|
|
* and "offset" will hold normalized values. Only directories are
|
|
* affected making it safe to call even for non-directory file
|
|
* types. */
|
|
static inline void
|
|
isofs_normalize_block_and_offset(struct iso_directory_record* de,
|
|
unsigned long *block,
|
|
unsigned long *offset)
|
|
{
|
|
/* Only directories are normalized. */
|
|
if (de->flags[0] & 2) {
|
|
*offset = 0;
|
|
*block = (unsigned long)isonum_733(de->extent)
|
|
+ (unsigned long)isonum_711(de->ext_attr_length);
|
|
}
|
|
}
|
|
|
|
extern const struct inode_operations isofs_dir_inode_operations;
|
|
extern const struct file_operations isofs_dir_operations;
|
|
extern const struct address_space_operations isofs_symlink_aops;
|
|
extern const struct export_operations isofs_export_ops;
|