wodim --devices and other commands fail

Solution Verified - Updated -

Environment

  • Red Hat Enterprise Linux (RHEL) 7.4
  • wodim-1.1.11-23.el7_4

Issue

On RHEL 7, trying to scan devices using wodim --devices or wodim -scanbus fails with following error:

wodim: No such file or directory. 
Cannot open SCSI driver!
For possible targets try 'wodim --devices' or 'wodim -scanbus'.
For possible transport specifiers try 'wodim dev=help'.
For IDE/ATAPI devices configuration, see the file README.ATAPI.setup from
the wodim documentation.

We would expect output like:

wodim: Overview of accessible drives (2 found) :
-------------------------------------------------------------------------
 0  dev='/dev/sg0'  rwrw-- : 'QEMU' 'QEMU DVD-ROM'
 1  dev='/dev/sg1'  rwrw-- : 'QEMU' 'QEMU CD-ROM'
-------------------------------------------------------------------------

Resolution

Update to cdrkit-1.1.11-25.el7 shipped with Advisory RHBA-2018:3109 or newer.

Root Cause

Due to bug in libusal library wodim previously failed recognizing correct kernel version and subsequently could not open corresponding drivers.

Diagnostic Steps

Using strace, we can see that /dev/sg* devices are not scanned.
This is due to a broken test against kernel 2.6 done in libusal, causing kernel 3.10 to be recognized as a 2.x kernel (x >= 6).

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