oss-security - CVE-2009-1883 kernel: missing capability check in z90crypt

Follow @Openwall on Twitter for new release announcements and other news

[<prev] [next>] [thread-next>] [day] [month] [year] [list]

Date: Tue, 15 Sep 2009 09:14:13 +0800
From: Eugene Teo <eugeneteo@...nel.sg>
To: oss-security@...ts.openwall.com
CC: "Steven M. Christey" <coley@...us.mitre.org>
Subject: CVE-2009-1883 kernel: missing capability check in z90crypt

There is a missing capability check in the z90crypt driver in the Linux 
kernel. This missing check could allow a local, unprivileged user to 
bypass intended capability restrictions. Thanks to Solar Designer for 
reporting this issue to us.

Note that this does not affect upstream anymore.

@@ -1887,20 +1887,21 @@ z90crypt_unlocked_ioctl(struct file *fil
      PRINTK("No longer issuing messages about depre"
             "cated ioctl Z90STAT_PCIXCCCOUNT.\n");
    }

    tempstat = get_status_PCIXCCcount();
    if (copy_to_user((int *)arg, &tempstat, sizeof(int)) != 0)
     ret = -EFAULT;
    break;

   case Z90QUIESCE:
    if (current->euid != 0) { <-- should check a capability
     PRINTK("QUIESCE fails: euid %d\n",
            current->euid);
     ret = -EACCES;
    } else {
     PRINTK("QUIESCE device from PID %d\n", PID());
     quiesce_z90crypt = 1;
    }
    break;

Thanks, Eugene

Please check out the Open Source Software Security Wiki, which is counterpart to this mailing list.

Confused about mailing lists and their use? Read about mailing lists on Wikipedia and check out these guidelines on proper formatting of your messages.