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    <head>
      <base href="https://llvm.org/bugs/" />
    </head>
    <body><table border="1" cellspacing="0" cellpadding="8">
        <tr>
          <th>Bug ID</th>
          <td><a class="bz_bug_link 
          bz_status_NEW "
   title="NEW --- - False positive Use-after-free about partclone/srv/btrfs/volumes.c line 170"
   href="https://llvm.org/bugs/show_bug.cgi?id=31458">31458</a>
          </td>
        </tr>

        <tr>
          <th>Summary</th>
          <td>False positive Use-after-free about partclone/srv/btrfs/volumes.c line 170
          </td>
        </tr>

        <tr>
          <th>Product</th>
          <td>clang
          </td>
        </tr>

        <tr>
          <th>Version</th>
          <td>3.9
          </td>
        </tr>

        <tr>
          <th>Hardware</th>
          <td>PC
          </td>
        </tr>

        <tr>
          <th>OS</th>
          <td>Linux
          </td>
        </tr>

        <tr>
          <th>Status</th>
          <td>NEW
          </td>
        </tr>

        <tr>
          <th>Severity</th>
          <td>normal
          </td>
        </tr>

        <tr>
          <th>Priority</th>
          <td>P
          </td>
        </tr>

        <tr>
          <th>Component</th>
          <td>Static Analyzer
          </td>
        </tr>

        <tr>
          <th>Assignee</th>
          <td>kremenek@apple.com
          </td>
        </tr>

        <tr>
          <th>Reporter</th>
          <td>xiangzhai83@gmail.com
          </td>
        </tr>

        <tr>
          <th>CC</th>
          <td>llvm-bugs@lists.llvm.org
          </td>
        </tr>

        <tr>
          <th>Classification</th>
          <td>Unclassified
          </td>
        </tr></table>
      <p>
        <div>
        <pre>Hi clang developers,

After reviewed the code
<a href="https://github.com/Thomas-Tsai/partclone/blob/master/src/btrfs/volumes.c#L164">https://github.com/Thomas-Tsai/partclone/blob/master/src/btrfs/volumes.c#L164</a>

I argue that it is false positive Use-after-free for Clang Static Analyzer
<a href="https://pbs.twimg.com/media/C0WBcn6VEAAS1Rp.jpg">https://pbs.twimg.com/media/C0WBcn6VEAAS1Rp.jpg</a>

because device is reassgin!

    while (!list_empty(&fs_devices->devices)) {
--- reassign ----> device = list_entry(fs_devices->devices.next,
                    struct btrfs_device, dev_list);
        if (device->fd != -1) {
            fsync(device->fd);
            if (posix_fadvise(device->fd, 0, 0, POSIX_FADV_DONTNEED))
                fprintf(stderr, "Warning, could not drop caches\n");
            close(device->fd);
            device->fd = -1;
        }
        device->writeable = 0;
        list_del(&device->dev_list);
        /* free the memory */
        free(device->name);
        free(device->label);
        free(device);
    }

Regards,
Leslie Zhai</pre>
        </div>
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