[LU-19907] Escaping bug in `dkms.conf` prevents `ko2iblnd` module from being installed when using external OFED

• Type: Bug
• Resolution: Unresolved
• Priority: Medium
• Affects Version/s: Lustre 2.17.0
• Environment: Debian 13 (trixie), kernel 6.12.73+deb13-amd64, DOCA-OFED 25.10.OFED.25.10.1.7.1.1
• Severity: 3
• Assignee: WC Triage
• Reporter: Kilian Cavalotti

Description

In debian/dkms.conf.in, the following line attempts to extract the --with-o2ib= path from $OPTS by splitting on spaces:

o2ib=$(echo ${OPTS} | tr ' ' '\\n' | grep -- '--with-o2ib=' | cut -c 13-)

But the '
n' argument to tr here is a literal backslash followed by n, not a newline character. As a result, tr replaces spaces with }} instead of newlines, causing {{grep to return the entire $OPTS string as a single token. The subsequent cut c 13 then strips only the first 12 characters of that blob, leaving a garbage value in o2ib instead of the intended path.

Because [[ d $o2ib ]] then fails, ext_mofed remains no even when -with-o2ib=/usr/src/ofa_kernel/default is explicitly set, and ko2iblnd is never added to BUILT_MODULE_NAME. The module is compiled correctly but not installed by DKMS.

Steps to reproduce:

1. Build lustre-client-modules-dkms with --with-o2ib=/usr/src/ofa_kernel/default
2. Install the resulting .deb
3. Observe that ko2iblnd.ko is absent from /lib/modules/$(uname -r)/updates/kernel/net/lustre/

An easy way to illustrate the problem is to run bash -x /var/lib/dkms/lustre-client-modules/<ver>/source/dkms.conf 2>&1 | grep ' o2ib=' to see the mangled value:

• current state:

$ bash -x /var/lib/dkms/lustre-client-modules/2.17.0/source/dkms.conf 2>&1 | grep ' o2ib='
+ o2ib='rver\--disable-quilt\--with-o2ib=/usr/src/ofa_kernel/default\--disable-dependency-tracking\--disable-doc\--disable-utils\--disable-iokit\--disable-tests\--enable-quota\--with-kmp-moddir=updates\--enable-gss'

• after having replaced 
  n with
  n :

$ bash -x /var/lib/dkms/lustre-client-modules/2.17.0/source/dkms.conf 2>&1 | grep ' o2ib='
+ o2ib=/usr/src/ofa_kernel/default