[1/1] fix(rootfs): create dev fd links under rootless

Message ID 20260819114328.759528-1-felix.moessbauer@siemens.com
State New
Headers show
Series [1/1] fix(rootfs): create dev fd links under rootless | expand

Commit Message

Felix Moessbauer Aug. 19, 2026, 11:43 a.m. UTC
The /dev/std{in,out.err} and /dev/fd entries are links into proc. While
these are not explicitly required by any Debian policy, mmdebstrap
creates them and they are used when installing systemd units under dracut.

We only observed warnings regarding the missing entries, but no issues
so far. Nonetheless, we now create them on-the-fly to behave similar to
mmdebstrap.

Fixes: 4fedb1ae ("add support for fully rootless builds")
Signed-off-by: Felix Moessbauer <felix.moessbauer@siemens.com>
---
 meta/classes-global/base.bbclass | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

Patch

diff --git a/meta/classes-global/base.bbclass b/meta/classes-global/base.bbclass
index f074eee6..e2fc77dc 100644
--- a/meta/classes-global/base.bbclass
+++ b/meta/classes-global/base.bbclass
@@ -401,6 +401,10 @@  def insert_isar_mounts(d, rootfs, mounts):
         lines.append('mount -o bind /dev/random {}/dev/random'.format(rootfs))
         lines.append('mount -o bind /dev/urandom {}/dev/urandom'.format(rootfs))
         lines.append('mount -t proc none {}/proc'.format(rootfs))
+        lines.append('ln -sfn /proc/self/fd {}/dev/fd'.format(rootfs))
+        lines.append('ln -sfn /proc/self/fd/0 {}/dev/stdin'.format(rootfs))
+        lines.append('ln -sfn /proc/self/fd/1 {}/dev/stdout'.format(rootfs))
+        lines.append('ln -sfn /proc/self/fd/2 {}/dev/stderr'.format(rootfs))
         # we do not unshare the network namespace, so we cannot create a sysfs, hence bind-mount
         lines.append('mount -o rbind /sys {}/sys'.format(rootfs))
 
@@ -417,7 +421,8 @@  def insert_isar_umounts(d, rootfs, mounts):
     remove the mountpoints.
     """
     lines = []
-    to_unlink = ['/dev/null', '/dev/random', '/dev/urandom', '/dev/ptmx']
+    to_unlink = ['/dev/null', '/dev/random', '/dev/urandom', '/dev/ptmx',
+                 '/dev/stdin', '/dev/stdout', '/dev/stderr', '/dev/fd']
     to_rmdir = ['/dev/pts', '/dev/shm']
     if d.getVar('ISAR_CHROOT_MODE') == 'unshare':
         lines.append('rm -f ' + ' '.join(['{}/{}'.format(rootfs, f) for f in to_unlink]))