#include "isofs.h"
#include "rock.h"
-/* These functions are designed to read the system areas of a directory record
+/*
+ * These functions are designed to read the system areas of a directory record
* and extract relevant information. There are different functions provided
* depending upon what information we need at the time. One function fills
* out an inode structure, a second one extracts a filename, a third one
* returns a symbolic link name, and a fourth one returns the extent number
- * for the file. */
+ * for the file.
+ */
#define SIG(A,B) ((A) | ((B) << 8)) /* isonum_721() */
+struct rock_state {
+ void *buffer;
+ unsigned char *chr;
+ int len;
+ int cont_size;
+ int cont_extent;
+ int cont_offset;
+ struct inode *inode;
+};
+
/*
* This is a way of ensuring that we have something in the system
- * use fields that is compatible with Rock Ridge. Return zero on success.
+ * use fields that is compatible with Rock Ridge. Return zero on success.
*/
static int check_sp(struct rock_ridge *rr, struct inode *inode)
return 0;
}
-#define CHECK_CE \
- {cont_extent = isonum_733(rr->u.CE.extent); \
- cont_offset = isonum_733(rr->u.CE.offset); \
- cont_size = isonum_733(rr->u.CE.size);}
-
-#define SETUP_ROCK_RIDGE(DE,CHR,LEN) \
- {LEN= sizeof(struct iso_directory_record) + DE->name_len[0]; \
- if(LEN & 1) LEN++; \
- CHR = ((unsigned char *) DE) + LEN; \
- LEN = *((unsigned char *) DE) - LEN; \
- if (LEN<0) LEN=0; \
- if (ISOFS_SB(inode->i_sb)->s_rock_offset!=-1) \
- { \
- LEN-=ISOFS_SB(inode->i_sb)->s_rock_offset; \
- CHR+=ISOFS_SB(inode->i_sb)->s_rock_offset; \
- if (LEN<0) LEN=0; \
- } \
+static void setup_rock_ridge(struct iso_directory_record *de,
+ struct inode *inode, struct rock_state *rs)
+{
+ rs->len = sizeof(struct iso_directory_record) + de->name_len[0];
+ if (rs->len & 1)
+ (rs->len)++;
+ rs->chr = (unsigned char *)de + rs->len;
+ rs->len = *((unsigned char *)de) - rs->len;
+ if (rs->len < 0)
+ rs->len = 0;
+
+ if (ISOFS_SB(inode->i_sb)->s_rock_offset != -1) {
+ rs->len -= ISOFS_SB(inode->i_sb)->s_rock_offset;
+ rs->chr += ISOFS_SB(inode->i_sb)->s_rock_offset;
+ if (rs->len < 0)
+ rs->len = 0;
+ }
+}
+
+static void init_rock_state(struct rock_state *rs, struct inode *inode)
+{
+ memset(rs, 0, sizeof(*rs));
+ rs->inode = inode;
+}
+
+/*
+ * Returns 0 if the caller should continue scanning, 1 if the scan must end
+ * and -ve on error.
+ */
+static int rock_continue(struct rock_state *rs)
+{
+ int ret = 1;
+ int blocksize = 1 << rs->inode->i_blkbits;
+ const int min_de_size = offsetof(struct rock_ridge, u);
+
+ kfree(rs->buffer);
+ rs->buffer = NULL;
+
+ if ((unsigned)rs->cont_offset > blocksize - min_de_size ||
+ (unsigned)rs->cont_size > blocksize ||
+ (unsigned)(rs->cont_offset + rs->cont_size) > blocksize) {
+ printk(KERN_NOTICE "rock: corrupted directory entry. "
+ "extent=%d, offset=%d, size=%d\n",
+ rs->cont_extent, rs->cont_offset, rs->cont_size);
+ ret = -EIO;
+ goto out;
+ }
+
+ if (rs->cont_extent) {
+ struct buffer_head *bh;
+
+ rs->buffer = kmalloc(rs->cont_size, GFP_KERNEL);
+ if (!rs->buffer) {
+ ret = -ENOMEM;
+ goto out;
+ }
+ ret = -EIO;
+ bh = sb_bread(rs->inode->i_sb, rs->cont_extent);
+ if (bh) {
+ memcpy(rs->buffer, bh->b_data + rs->cont_offset,
+ rs->cont_size);
+ put_bh(bh);
+ rs->chr = rs->buffer;
+ rs->len = rs->cont_size;
+ rs->cont_extent = 0;
+ rs->cont_size = 0;
+ rs->cont_offset = 0;
+ return 0;
+ }
+ printk("Unable to read rock-ridge attributes\n");
+ }
+out:
+ kfree(rs->buffer);
+ rs->buffer = NULL;
+ return ret;
+}
+
+/*
+ * We think there's a record of type `sig' at rs->chr. Parse the signature
+ * and make sure that there's really room for a record of that type.
+ */
+static int rock_check_overflow(struct rock_state *rs, int sig)
+{
+ int len;
+
+ switch (sig) {
+ case SIG('S', 'P'):
+ len = sizeof(struct SU_SP_s);
+ break;
+ case SIG('C', 'E'):
+ len = sizeof(struct SU_CE_s);
+ break;
+ case SIG('E', 'R'):
+ len = sizeof(struct SU_ER_s);
+ break;
+ case SIG('R', 'R'):
+ len = sizeof(struct RR_RR_s);
+ break;
+ case SIG('P', 'X'):
+ len = sizeof(struct RR_PX_s);
+ break;
+ case SIG('P', 'N'):
+ len = sizeof(struct RR_PN_s);
+ break;
+ case SIG('S', 'L'):
+ len = sizeof(struct RR_SL_s);
+ break;
+ case SIG('N', 'M'):
+ len = sizeof(struct RR_NM_s);
+ break;
+ case SIG('C', 'L'):
+ len = sizeof(struct RR_CL_s);
+ break;
+ case SIG('P', 'L'):
+ len = sizeof(struct RR_PL_s);
+ break;
+ case SIG('T', 'F'):
+ len = sizeof(struct RR_TF_s);
+ break;
+ case SIG('Z', 'F'):
+ len = sizeof(struct RR_ZF_s);
+ break;
+ default:
+ len = 0;
+ break;
+ }
+ len += offsetof(struct rock_ridge, u);
+ if (len > rs->len) {
+ printk(KERN_NOTICE "rock: directory entry would overflow "
+ "storage\n");
+ printk(KERN_NOTICE "rock: sig=0x%02x, size=%d, remaining=%d\n",
+ sig, len, rs->len);
+ return -EIO;
+ }
+ return 0;
}
-#define MAYBE_CONTINUE(LABEL,DEV) \
- {if (buffer) { kfree(buffer); buffer = NULL; } \
- if (cont_extent){ \
- int block, offset, offset1; \
- struct buffer_head * pbh; \
- buffer = kmalloc(cont_size,GFP_KERNEL); \
- if (!buffer) goto out; \
- block = cont_extent; \
- offset = cont_offset; \
- offset1 = 0; \
- pbh = sb_bread(DEV->i_sb, block); \
- if(pbh){ \
- if (offset > pbh->b_size || offset + cont_size > pbh->b_size){ \
- brelse(pbh); \
- goto out; \
- } \
- memcpy(buffer + offset1, pbh->b_data + offset, cont_size - offset1); \
- brelse(pbh); \
- chr = (unsigned char *) buffer; \
- len = cont_size; \
- cont_extent = 0; \
- cont_size = 0; \
- cont_offset = 0; \
- goto LABEL; \
- } \
- printk("Unable to read rock-ridge attributes\n"); \
- }}
-
-/* return length of name field; 0: not found, -1: to be ignored */
+/*
+ * return length of name field; 0: not found, -1: to be ignored
+ */
int get_rock_ridge_filename(struct iso_directory_record *de,
char *retname, struct inode *inode)
{
- int len;
- unsigned char *chr;
- int cont_extent = 0;
- int cont_offset = 0;
- int cont_size = 0;
- void *buffer = NULL;
+ struct rock_state rs;
struct rock_ridge *rr;
int sig;
int retnamlen = 0;
int truncate = 0;
+ int ret = 0;
if (!ISOFS_SB(inode->i_sb)->s_rock)
return 0;
*retname = 0;
- SETUP_ROCK_RIDGE(de, chr, len);
+ init_rock_state(&rs, inode);
+ setup_rock_ridge(de, inode, &rs);
repeat:
- while (len > 2) { /* There may be one byte for padding somewhere */
- rr = (struct rock_ridge *)chr;
+ while (rs.len > 2) { /* There may be one byte for padding somewhere */
+ rr = (struct rock_ridge *)rs.chr;
if (rr->len < 3)
goto out; /* Something got screwed up here */
- sig = isonum_721(chr);
- chr += rr->len;
- len -= rr->len;
- if (len < 0)
- goto out; /* corrupted isofs */
+ sig = isonum_721(rs.chr);
+ if (rock_check_overflow(&rs, sig))
+ goto eio;
+ rs.chr += rr->len;
+ rs.len -= rr->len;
+ if (rs.len < 0)
+ goto eio; /* corrupted isofs */
switch (sig) {
case SIG('R', 'R'):
goto out;
break;
case SIG('C', 'E'):
- CHECK_CE;
+ rs.cont_extent = isonum_733(rr->u.CE.extent);
+ rs.cont_offset = isonum_733(rr->u.CE.offset);
+ rs.cont_size = isonum_733(rr->u.CE.size);
break;
case SIG('N', 'M'):
if (truncate)
retnamlen += rr->len - 5;
break;
case SIG('R', 'E'):
- if (buffer)
- kfree(buffer);
+ kfree(rs.buffer);
return -1;
default:
break;
}
}
- MAYBE_CONTINUE(repeat, inode);
- kfree(buffer);
- return retnamlen; /* If 0, this file did not have a NM field */
+ ret = rock_continue(&rs);
+ if (ret == 0)
+ goto repeat;
+ if (ret == 1)
+ return retnamlen; /* If 0, this file did not have a NM field */
out:
- if (buffer)
- kfree(buffer);
- return 0;
+ kfree(rs.buffer);
+ return ret;
+eio:
+ ret = -EIO;
+ goto out;
}
static int
parse_rock_ridge_inode_internal(struct iso_directory_record *de,
struct inode *inode, int regard_xa)
{
- int len;
- unsigned char *chr;
int symlink_len = 0;
int cnt, sig;
struct inode *reloc;
struct rock_ridge *rr;
int rootflag;
- int cont_extent = 0;
- int cont_offset = 0;
- int cont_size = 0;
- void *buffer = NULL;
+ struct rock_state rs;
+ int ret = 0;
if (!ISOFS_SB(inode->i_sb)->s_rock)
return 0;
- SETUP_ROCK_RIDGE(de, chr, len);
+ init_rock_state(&rs, inode);
+ setup_rock_ridge(de, inode, &rs);
if (regard_xa) {
- chr += 14;
- len -= 14;
- if (len < 0)
- len = 0;
+ rs.chr += 14;
+ rs.len -= 14;
+ if (rs.len < 0)
+ rs.len = 0;
}
repeat:
- while (len > 2) { /* There may be one byte for padding somewhere */
- rr = (struct rock_ridge *)chr;
+ while (rs.len > 2) { /* There may be one byte for padding somewhere */
+ rr = (struct rock_ridge *)rs.chr;
if (rr->len < 3)
goto out; /* Something got screwed up here */
- sig = isonum_721(chr);
- chr += rr->len;
- len -= rr->len;
- if (len < 0)
- goto out; /* corrupted isofs */
+ sig = isonum_721(rs.chr);
+ if (rock_check_overflow(&rs, sig))
+ goto eio;
+ rs.chr += rr->len;
+ rs.len -= rr->len;
+ if (rs.len < 0)
+ goto eio; /* corrupted isofs */
switch (sig) {
#ifndef CONFIG_ZISOFS /* No flag for SF or ZF */
goto out;
break;
case SIG('C', 'E'):
- CHECK_CE;
+ rs.cont_extent = isonum_733(rr->u.CE.extent);
+ rs.cont_offset = isonum_733(rr->u.CE.offset);
+ rs.cont_size = isonum_733(rr->u.CE.size);
break;
case SIG('E', 'R'):
ISOFS_SB(inode->i_sb)->s_rock = 1;
break;
}
}
- MAYBE_CONTINUE(repeat, inode);
+ ret = rock_continue(&rs);
+ if (ret == 0)
+ goto repeat;
+ if (ret == 1)
+ ret = 0;
out:
- if (buffer)
- kfree(buffer);
- return 0;
+ kfree(rs.buffer);
+ return ret;
+eio:
+ ret = -EIO;
+ goto out;
}
static char *get_symlink_chunk(char *rpnt, struct rock_ridge *rr, char *plimit)
int parse_rock_ridge_inode(struct iso_directory_record *de, struct inode *inode)
{
int result = parse_rock_ridge_inode_internal(de, inode, 0);
- /* if rockridge flag was reset and we didn't look for attributes
- * behind eventual XA attributes, have a look there */
+
+ /*
+ * if rockridge flag was reset and we didn't look for attributes
+ * behind eventual XA attributes, have a look there
+ */
if ((ISOFS_SB(inode->i_sb)->s_rock_offset == -1)
&& (ISOFS_SB(inode->i_sb)->s_rock == 2)) {
result = parse_rock_ridge_inode_internal(de, inode, 14);
return result;
}
-/* readpage() for symlinks: reads symlink contents into the page and either
- makes it uptodate and returns 0 or returns error (-EIO) */
-
+/*
+ * readpage() for symlinks: reads symlink contents into the page and either
+ * makes it uptodate and returns 0 or returns error (-EIO)
+ */
static int rock_ridge_symlink_readpage(struct file *file, struct page *page)
{
struct inode *inode = page->mapping->host;
struct buffer_head *bh;
char *rpnt = link;
unsigned char *pnt;
- struct iso_directory_record *raw_inode;
- int cont_extent = 0;
- int cont_offset = 0;
- int cont_size = 0;
- void *buffer = NULL;
+ struct iso_directory_record *raw_de;
unsigned long block, offset;
int sig;
- int len;
- unsigned char *chr;
struct rock_ridge *rr;
+ struct rock_state rs;
+ int ret;
if (!ISOFS_SB(inode->i_sb)->s_rock)
goto error;
+ init_rock_state(&rs, inode);
block = ei->i_iget5_block;
lock_kernel();
bh = sb_bread(inode->i_sb, block);
offset = ei->i_iget5_offset;
pnt = (unsigned char *)bh->b_data + offset;
- raw_inode = (struct iso_directory_record *)pnt;
+ raw_de = (struct iso_directory_record *)pnt;
/*
* If we go past the end of the buffer, there is some sort of error.
if (offset + *pnt > bufsize)
goto out_bad_span;
- /* Now test for possible Rock Ridge extensions which will override
- some of these numbers in the inode structure. */
+ /*
+ * Now test for possible Rock Ridge extensions which will override
+ * some of these numbers in the inode structure.
+ */
- SETUP_ROCK_RIDGE(raw_inode, chr, len);
+ setup_rock_ridge(raw_de, inode, &rs);
repeat:
- while (len > 2) { /* There may be one byte for padding somewhere */
- rr = (struct rock_ridge *)chr;
+ while (rs.len > 2) { /* There may be one byte for padding somewhere */
+ rr = (struct rock_ridge *)rs.chr;
if (rr->len < 3)
goto out; /* Something got screwed up here */
- sig = isonum_721(chr);
- chr += rr->len;
- len -= rr->len;
- if (len < 0)
+ sig = isonum_721(rs.chr);
+ if (rock_check_overflow(&rs, sig))
+ goto out;
+ rs.chr += rr->len;
+ rs.len -= rr->len;
+ if (rs.len < 0)
goto out; /* corrupted isofs */
switch (sig) {
break;
case SIG('C', 'E'):
/* This tells is if there is a continuation record */
- CHECK_CE;
+ rs.cont_extent = isonum_733(rr->u.CE.extent);
+ rs.cont_offset = isonum_733(rr->u.CE.offset);
+ rs.cont_size = isonum_733(rr->u.CE.size);
default:
break;
}
}
- MAYBE_CONTINUE(repeat, inode);
- kfree(buffer);
+ ret = rock_continue(&rs);
+ if (ret == 0)
+ goto repeat;
+ if (ret < 0)
+ goto fail;
if (rpnt == link)
goto fail;
/* error exit from macro */
out:
- if (buffer)
- kfree(buffer);
+ kfree(rs.buffer);
goto fail;
out_noread:
printk("unable to read i-node block");
return -EIO;
}
-struct address_space_operations isofs_symlink_aops = {
+const struct address_space_operations isofs_symlink_aops = {
.readpage = rock_ridge_symlink_readpage
};
git://ftp.safe.ca / safe / jmp / linux-2.6 / blobdiff