[JFFS2] Fix node allocation leak
Thomas Gleixner [Fri, 15 Jul 2005 06:14:44 +0000 (08:14 +0200)]
In the rare case of failing to write the cleanmarker
the allocated node was not freed.

Pointed out by Forrest Zhao
Initial cleanup by Joern Engel

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

fs/jffs2/erase.c

index 6a4c0a3..787d84a 100644 (file)
@@ -7,7 +7,7 @@
  *
  * For licensing information, see the file 'LICENCE' in this directory.
  *
- * $Id: erase.c,v 1.76 2005/05/03 15:11:40 dedekind Exp $
+ * $Id: erase.c,v 1.80 2005/07/14 19:46:24 joern Exp $
  *
  */
 
@@ -300,100 +300,86 @@ static void jffs2_free_all_node_refs(struct jffs2_sb_info *c, struct jffs2_erase
        jeb->last_node = NULL;
 }
 
-static void jffs2_mark_erased_block(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb)
+static int jffs2_block_check_erase(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb, uint32_t *bad_offset)
 {
-       struct jffs2_raw_node_ref *marker_ref = NULL;
-       unsigned char *ebuf;
+       void *ebuf;
+       uint32_t ofs;
        size_t retlen;
-       int ret;
-       uint32_t bad_offset;
-
-       if ((!jffs2_cleanmarker_oob(c)) && (c->cleanmarker_size > 0)) {
-               marker_ref = jffs2_alloc_raw_node_ref();
-               if (!marker_ref) {
-                       printk(KERN_WARNING "Failed to allocate raw node ref for clean marker\n");
-                       /* Stick it back on the list from whence it came and come back later */
-                       jffs2_erase_pending_trigger(c);
-                       spin_lock(&c->erase_completion_lock);
-                       list_add(&jeb->list, &c->erase_complete_list);
-                       spin_unlock(&c->erase_completion_lock);
-                       return;
-               }
-       }
+       int ret = -EIO;
+       
        ebuf = kmalloc(PAGE_SIZE, GFP_KERNEL);
        if (!ebuf) {
-               printk(KERN_WARNING "Failed to allocate page buffer for verifying erase at 0x%08x. Assuming it worked\n", jeb->offset);
-       } else {
-               uint32_t ofs = jeb->offset;
+               printk(KERN_WARNING "Failed to allocate page buffer for verifying erase at 0x%08x. Refiling\n", jeb->offset);
+               return -EAGAIN;
+       }
 
-               D1(printk(KERN_DEBUG "Verifying erase at 0x%08x\n", jeb->offset));
-               while(ofs < jeb->offset + c->sector_size) {
-                       uint32_t readlen = min((uint32_t)PAGE_SIZE, jeb->offset + c->sector_size - ofs);
-                       int i;
+       D1(printk(KERN_DEBUG "Verifying erase at 0x%08x\n", jeb->offset));
 
-                       bad_offset = ofs;
+       for (ofs = jeb->offset; ofs < jeb->offset + c->sector_size; ) {
+               uint32_t readlen = min((uint32_t)PAGE_SIZE, jeb->offset + c->sector_size - ofs);
+               int i;
 
-                       ret = c->mtd->read(c->mtd, ofs, readlen, &retlen, ebuf);
+               *bad_offset = ofs;
 
-                       if (ret) {
-                               printk(KERN_WARNING "Read of newly-erased block at 0x%08x failed: %d. Putting on bad_list\n", ofs, ret);
-                               goto bad;
-                       }
-                       if (retlen != readlen) {
-                               printk(KERN_WARNING "Short read from newly-erased block at 0x%08x. Wanted %d, got %zd\n", ofs, readlen, retlen);
-                               goto bad;
-                       }
-                       for (i=0; i<readlen; i += sizeof(unsigned long)) {
-                               /* It's OK. We know it's properly aligned */
-                               unsigned long datum = *(unsigned long *)(&ebuf[i]);
-                               if (datum + 1) {
-                                       bad_offset += i;
-                                       printk(KERN_WARNING "Newly-erased block contained word 0x%lx at offset 0x%08x\n", datum, bad_offset);
-                               bad: 
-                                       if ((!jffs2_cleanmarker_oob(c)) && (c->cleanmarker_size > 0))
-                                               jffs2_free_raw_node_ref(marker_ref);
-                                       kfree(ebuf);
-                               bad2:
-                                       spin_lock(&c->erase_completion_lock);
-                                       /* Stick it on a list (any list) so
-                                          erase_failed can take it right off
-                                          again.  Silly, but shouldn't happen
-                                          often. */
-                                       list_add(&jeb->list, &c->erasing_list);
-                                       spin_unlock(&c->erase_completion_lock);
-                                       jffs2_erase_failed(c, jeb, bad_offset);
-                                       return;
-                               }
+               ret = jffs2_flash_read(c, ofs, readlen, &retlen, ebuf);
+               if (ret) {
+                       printk(KERN_WARNING "Read of newly-erased block at 0x%08x failed: %d. Putting on bad_list\n", ofs, ret);
+                       goto fail;
+               }
+               if (retlen != readlen) {
+                       printk(KERN_WARNING "Short read from newly-erased block at 0x%08x. Wanted %d, got %zd\n", ofs, readlen, retlen);
+                       goto fail;
+               }
+               for (i=0; i<readlen; i += sizeof(unsigned long)) {
+                       /* It's OK. We know it's properly aligned */
+                       unsigned long *datum = ebuf + i;
+                       if (*datum + 1) {
+                               *bad_offset += i;
+                               printk(KERN_WARNING "Newly-erased block contained word 0x%lx at offset 0x%08x\n", *datum, *bad_offset);
+                               goto fail;
                        }
-                       ofs += readlen;
-                       cond_resched();
                }
-               kfree(ebuf);
+               ofs += readlen;
+               cond_resched();
        }
+       ret = 0;
+fail:
+       kfree(ebuf);
+       return ret;
+}
 
-       bad_offset = jeb->offset;
+static void jffs2_mark_erased_block(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb)
+{
+       struct jffs2_raw_node_ref *marker_ref = NULL;
+       size_t retlen;
+       int ret;
+       uint32_t bad_offset;
+
+       switch (jffs2_block_check_erase(c, jeb, &bad_offset)) {
+       case -EAGAIN:   goto refile;
+       case -EIO:      goto filebad;
+       }
 
        /* Write the erase complete marker */   
        D1(printk(KERN_DEBUG "Writing erased marker to block at 0x%08x\n", jeb->offset));
-       if (jffs2_cleanmarker_oob(c)) {
+       bad_offset = jeb->offset;
 
-               if (jffs2_write_nand_cleanmarker(c, jeb))
-                       goto bad2;
-                       
-               jeb->first_node = jeb->last_node = NULL;
+       /* Cleanmarker in oob area or no cleanmarker at all ? */
+       if (jffs2_cleanmarker_oob(c) || c->cleanmarker_size == 0) {
 
-               jeb->free_size = c->sector_size;
-               jeb->used_size = 0;
-               jeb->dirty_size = 0;
-               jeb->wasted_size = 0;
-       } else if (c->cleanmarker_size == 0) {
-               jeb->first_node = jeb->last_node = NULL;
+               if (jffs2_cleanmarker_oob(c)) {
+                       if (jffs2_write_nand_cleanmarker(c, jeb))
+                               goto filebad;
+               }
 
+               jeb->first_node = jeb->last_node = NULL;
                jeb->free_size = c->sector_size;
                jeb->used_size = 0;
                jeb->dirty_size = 0;
                jeb->wasted_size = 0;
+
        } else {
+
                struct kvec vecs[1];
                struct jffs2_unknown_node marker = {
                        .magic =        cpu_to_je16(JFFS2_MAGIC_BITMASK),
@@ -401,21 +387,28 @@ static void jffs2_mark_erased_block(struct jffs2_sb_info *c, struct jffs2_eraseb
                        .totlen =       cpu_to_je32(c->cleanmarker_size)
                };
 
+               marker_ref = jffs2_alloc_raw_node_ref();
+               if (!marker_ref) {
+                       printk(KERN_WARNING "Failed to allocate raw node ref for clean marker. Refiling\n");
+                       goto refile;
+               }
+
                marker.hdr_crc = cpu_to_je32(crc32(0, &marker, sizeof(struct jffs2_unknown_node)-4));
 
                vecs[0].iov_base = (unsigned char *) &marker;
                vecs[0].iov_len = sizeof(marker);
                ret = jffs2_flash_direct_writev(c, vecs, 1, jeb->offset, &retlen);
                
-               if (ret) {
-                       printk(KERN_WARNING "Write clean marker to block at 0x%08x failed: %d\n",
-                              jeb->offset, ret);
-                       goto bad2;
-               }
-               if (retlen != sizeof(marker)) {
-                       printk(KERN_WARNING "Short write to newly-erased block at 0x%08x: Wanted %zd, got %zd\n",
-                              jeb->offset, sizeof(marker), retlen);
-                       goto bad2;
+               if (ret || retlen != sizeof(marker)) {
+                       if (ret)
+                               printk(KERN_WARNING "Write clean marker to block at 0x%08x failed: %d\n",
+                                      jeb->offset, ret);
+                       else
+                               printk(KERN_WARNING "Short write to newly-erased block at 0x%08x: Wanted %zd, got %zd\n",
+                                      jeb->offset, sizeof(marker), retlen);
+
+                       jffs2_free_raw_node_ref(marker_ref);
+                       goto filebad;
                }
 
                marker_ref->next_in_ino = NULL;
@@ -444,5 +437,22 @@ static void jffs2_mark_erased_block(struct jffs2_sb_info *c, struct jffs2_eraseb
        c->nr_free_blocks++;
        spin_unlock(&c->erase_completion_lock);
        wake_up(&c->erase_wait);
-}
+       return;
+
+filebad:
+       spin_lock(&c->erase_completion_lock);
+       /* Stick it on a list (any list) so erase_failed can take it
+          right off again.  Silly, but shouldn't happen often. */
+       list_add(&jeb->list, &c->erasing_list);
+       spin_unlock(&c->erase_completion_lock);
+       jffs2_erase_failed(c, jeb, bad_offset);
+       return;
 
+refile:
+       /* Stick it back on the list from whence it came and come back later */
+       jffs2_erase_pending_trigger(c);
+       spin_lock(&c->erase_completion_lock);
+       list_add(&jeb->list, &c->erase_complete_list);
+       spin_unlock(&c->erase_completion_lock);
+       return;
+}