[Bug 2095518] [NEW] dracut-install does not install compressed wildcard blobs

[Launchpad Bug Tracker]

You have been subscribed to a public bug by You-Sheng Yang (vicamo):

[SRU Justificaiton]

[ Impact ]

Linux kernel modules may declare firmware blobs to be installed along
with the module itself to ensure driver functions, and the paths may
contains wildcards to be expanded by other tools.

```
$ find /lib/modules/$(uname -r) -name \*.ko.zst -exec bash -c "m=\$(basename "{}"); m=\${m%%.*}; modinfo \$m|grep '^firmware:.*\*'" \;
firmware: brcm/brcmbt4388*.ptb
firmware: brcm/brcmbt4388*.bin
firmware: brcm/brcmbt4387*.ptb
firmware: brcm/brcmbt4387*.bin
firmware: brcm/brcmbt4378*.ptb
firmware: brcm/brcmbt4378*.bin
firmware: brcm/brcmbt4377*.ptb
firmware: brcm/brcmbt4377*.bin
firmware: intel/ish/ish_*.bin
firmware: ath11k/WCN6855/hw2.1/*
firmware: ath11k/WCN6855/hw2.0/*
firmware: ath11k/QCN9074/hw1.0/*
firmware: ath11k/QCA6390/hw2.0/*
firmware: brcm/brcmfmac*-sdio.*.bin
firmware: brcm/brcmfmac*-sdio.*.txt
firmware: brcm/brcmfmac*-pcie.*.txcap_blob
firmware: brcm/brcmfmac*-pcie.*.clm_blob
firmware: brcm/brcmfmac*-pcie.*.bin
firmware: brcm/brcmfmac*-pcie.*.txt
firmware: brcm/brcmfmac*-pcie.txt
```

dracut is the tool that helps building initramfs at this moment, and
it's implementation for resolving compressed firmware blobs (and
therefore a different filename suffix) doesn't really handle it
(wildcard in the middle) correctly. This causes wildcard firmwares, even
needed by the system, may not be packed into initramfs as expected.

Usually this is not a big deal, and we have been switching to xz/zst for
a while. However, in Intel ISH driver, it declares:

```
firmware:       intel/ish/ish_*.bin
firmware:       intel/ish/ish_lnlm.bin
```

It tries to resolve the best match of a vendor/model specific
configuration by DMI info, and since the ones matched with that wildcard
filename will never be installed into initramfs, leaving only the
generic blob available and always available at driver loading, it will
use the generic firmware unconditionally and break sensor functions for
a few platforms.

The fix tries to rewrite the resolution in dracut a bit, so that it will
match and copy compressed blobs as well.

[ Test Plan ]

1. touch `/lib/firmware/intel/ish/ish_foo.bin.zst`
2. `update-initramefs -v -u -k $(uname -r)`, and check if above file was added.

[ Where problems could occur ]

 * This fix will then add brcm, ish firmware blobs into initramfs if
necessary for the running platform as they should have been. Would
slightly increase initramfs size if affected.

[ Other Info ]

* First found for dracut >= 060, used by Ubuntu Noble, and extent to
Jammy/Oracular/Plucky as well.

* Upstream bug and pull request in review: https://github.com/dracut-
ng/dracut-ng/issues/1150

========== original bug report ==========

[Describe the bug]

Take kernel module intel-ish-ipc for example, it has two firmware
declarations:

```
$ modinfo intel-ish-ipc | grep ^firmware
firmware: intel/ish/ish_*.bin
firmware: intel/ish/ish_lnlm.bin
```

And with additional custom ISH firmware installed from [bug
2094768](https://bugs.launchpad.net/bugs/2094768), update-initramefs
gives:

```
$ update-initramefs -v -u -k $(uname -r)
...
dracut-install: Missing firmware intel/ish/ish_*.bin for kernel module intel_ish_ipc
dracut-install: mkdir '/var/tmp/mkinitramfs_9uk7FI/lib/firmware/intel/ish'
dracut-install: cp '/lib/firmware/intel/ish/ish_lnlm_39ceeaf8_58.7724.2.bin.zst' '/var/tmp/mkinitramfs_9uk7FI/lib/firmware/intel/ish/ish_lnlm_39ceeaf8_58.7724.2.bin.zst'
dracut-install: ln -s 'ish_lnlm_39ceeaf8_58.7724.2.bin.zst' '/var/tmp/mkinitramfs_9uk7FI/lib/firmware/intel/ish/ish_lnlm.bin.zst'
...
```

In source code for `/usr/lib/dracut/dracut-install`, that is, source
package dracut, file `src/install/dracut-install.c`, function
`install_firmware`, it tries to invoke `glob()` with full path expanded
from "intel/ish/ish_*.bin", but while all the binaries were compressed,
this matches no file and none of the custom ISH firmware blobs will be
installed.

[Distribution used]

Ubuntu

[Dracut version]

This was first found in Ubuntu/Noble, which has 060, but from the git
history and the differences, this should be reproducible with all
versions of dracut.

[Init system]

Systemd.

[To Reproduce]

1. touch `/lib/firmware/intel/ish/ish_foo.bin.zst`
2. `update-initramefs -v -u -k $(uname -r)`, and check if above file was added.

[Expected behavior]

Any file under `/lib/firmware/intel/ish` matches `intel/ish/ish_*.bin`,
compressed (.zst, .xz) or uncompressed (.bin), should be added into the
newly created initramefs.

[Additional context]

Upstream bug: https://github.com/dracut-ng/dracut-ng/issues/1150

** Affects: dracut (Ubuntu)
     Importance: High
     Assignee: You-Sheng Yang (vicamo)
         Status: In Progress

** Affects: dracut (Ubuntu Jammy)
     Importance: High
     Assignee: You-Sheng Yang (vicamo)
         Status: Triaged

** Affects: dracut (Ubuntu Noble)
     Importance: High
     Assignee: You-Sheng Yang (vicamo)
         Status: In Progress

** Affects: dracut (Ubuntu Oracular)
     Importance: High
     Assignee: You-Sheng Yang (vicamo)
         Status: In Progress

** Affects: dracut (Ubuntu Plucky)
     Importance: High
     Assignee: You-Sheng Yang (vicamo)
         Status: In Progress

-- 
dracut-install does not install compressed wildcard blobs
https://bugs.launchpad.net/bugs/2095518
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