Merge to Fedora kernel-2.6.18-1.2239_FC5 patched with stable patch-2.6.18.2-vs2.0...

[linux-2.6.git] / fs / buffer.c

diff --git a/fs/buffer.c b/fs/buffer.c
index 9f27576..a61beb1 100644 (file)
--- a/fs/buffer.c
+++ b/fs/buffer.c
@@ -1181,8 +1181,21 @@ grow_buffers(struct block_device *bdev, sector_t block, int size)
        } while ((size << sizebits) < PAGE_SIZE);
 
        index = block >> sizebits;
-       block = index << sizebits;
 
+       /*
+        * Check for a block which wants to lie outside our maximum possible
+        * pagecache index.  (this comparison is done using sector_t types).
+        */
+       if (unlikely(index != block >> sizebits)) {
+               char b[BDEVNAME_SIZE];
+
+               printk(KERN_ERR "%s: requested out-of-range block %llu for "
+                       "device %s\n",
+                       __FUNCTION__, (unsigned long long)block,
+                       bdevname(bdev, b));
+               return -EIO;
+       }
+       block = index << sizebits;
        /* Create a page with the proper size buffers.. */
        page = grow_dev_page(bdev, block, index, size);
        if (!page)
@@ -1209,12 +1222,16 @@ __getblk_slow(struct block_device *bdev, sector_t block, int size)
 
        for (;;) {
                struct buffer_head * bh;
+               int ret;
 
                bh = __find_get_block(bdev, block, size);
                if (bh)
                        return bh;
 
-               if (!grow_buffers(bdev, block, size))
+               ret = grow_buffers(bdev, block, size);
+               if (ret < 0)
+                       return NULL;
+               if (ret == 0)
                        free_more_memory();
        }
 }