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");