diff options
-rw-r--r-- | fs/isofs/rock.c | 237 |
1 files changed, 130 insertions, 107 deletions
diff --git a/fs/isofs/rock.c b/fs/isofs/rock.c index aafe356ec1b7..efefbcce4ce9 100644 --- a/fs/isofs/rock.c +++ b/fs/isofs/rock.c @@ -22,6 +22,16 @@ #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. @@ -38,82 +48,96 @@ static int check_sp(struct rock_ridge *rr, struct inode *inode) } static void setup_rock_ridge(struct iso_directory_record *de, - struct inode *inode, unsigned char **chr, int *len) + struct inode *inode, struct rock_state *rs) { - *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; + 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) { - *len -= ISOFS_SB(inode->i_sb)->s_rock_offset; - *chr += ISOFS_SB(inode->i_sb)->s_rock_offset; - if (*len < 0) - *len = 0; + 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; } } -#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"); \ - }} +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; + + kfree(rs->buffer); + rs->buffer = NULL; + 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; +} /* 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, inode, &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) + sig = isonum_721(rs.chr); + rs.chr += rr->len; + rs.len -= rr->len; + if (rs.len < 0) goto out; /* corrupted isofs */ switch (sig) { @@ -126,9 +150,9 @@ repeat: goto out; break; case SIG('C', 'E'): - cont_extent = isonum_733(rr->u.CE.extent); - cont_offset = isonum_733(rr->u.CE.offset); - cont_size = isonum_733(rr->u.CE.size); + 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) @@ -158,58 +182,55 @@ repeat: 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; } 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, inode, &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) + sig = isonum_721(rs.chr); + rs.chr += rr->len; + rs.len -= rr->len; + if (rs.len < 0) goto out; /* corrupted isofs */ switch (sig) { @@ -225,9 +246,9 @@ repeat: goto out; break; case SIG('C', 'E'): - cont_extent = isonum_733(rr->u.CE.extent); - cont_offset = isonum_733(rr->u.CE.offset); - cont_size = isonum_733(rr->u.CE.size); + 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; @@ -433,11 +454,14 @@ repeat: 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; } static char *get_symlink_chunk(char *rpnt, struct rock_ridge *rr, char *plimit) @@ -533,19 +557,16 @@ static int rock_ridge_symlink_readpage(struct file *file, struct page *page) char *rpnt = link; unsigned char *pnt; struct iso_directory_record *raw_de; - int cont_extent = 0; - int cont_offset = 0; - int cont_size = 0; - void *buffer = NULL; 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); @@ -566,17 +587,17 @@ static int rock_ridge_symlink_readpage(struct file *file, struct page *page) /* Now test for possible Rock Ridge extensions which will override some of these numbers in the inode structure. */ - setup_rock_ridge(raw_de, 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); + rs.chr += rr->len; + rs.len -= rr->len; + if (rs.len < 0) goto out; /* corrupted isofs */ switch (sig) { @@ -596,15 +617,18 @@ repeat: break; case SIG('C', 'E'): /* This tells is if there is a continuation record */ - cont_extent = isonum_733(rr->u.CE.extent); - cont_offset = isonum_733(rr->u.CE.offset); - cont_size = isonum_733(rr->u.CE.size); + 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; @@ -618,8 +642,7 @@ repeat: /* error exit from macro */ out: - if (buffer) - kfree(buffer); + kfree(rs.buffer); goto fail; out_noread: printk("unable to read i-node block"); |