scripts/pahole-flags.sh change return to exit 0

[David Thompson]

BugLink: https://bugs.launchpad.net/bugs/2035123

[Impact]

When building the Jammy linux-bluefield kernel tree on a system without pahole installed, the following warning is emitted:

./scripts/pahole-flags.sh: line 7: return: can only `return' from a function or sourced script

scripts/pahole-flags.sh attempts to return from an if statement that is not within a function, and generates a warning.

The fix is straightforward, changing return to an exit 0.

--- a/scripts/pahole-flags.sh
+++ b/scripts/pahole-flags.sh
@@ -4,7 +4,7 @@
 extra_paholeopt=

 if ! [ -x "$(command -v ${PAHOLE})" ]; then
- return
+ exit 0
 fi

[Testcase]

Clone the linux-bluefield kernel tree and build it on a arm64 system without
pahole installed.

A test kernel is available with the fix applied in:

https://launchpad.net/~mruffell/+archive/ubuntu/sf368560-test

Both linux-bluefield and ubuntu-jammy build correctly.

[Fix]

This was fixed by Linus Torvalds in the following merge commit:

commit fc02cb2b37fe2cbf1d3334b9f0f0eab9431766c4
Merge: bfc484fe6abb 84882cf72cd7
Author: Linus Torvalds <email address hidden>
Date: Tue Nov 2 06:20:58 2021 -0700
Subject: Merge tag 'net-next-for-5.16' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next
Link: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=fc02cb2b37fe2cbf1d3334b9f0f0eab9431766c4

Note, the original commit does not have the fix included:

commit 9741e07ece7c247dd65e1aa01e16b683f01c05a8
Author: Jiri Olsa <email address hidden>
Date: Fri Oct 29 14:57:29 2021 +0200
Subject: kbuild: Unify options for BTF generation for vmlinux and modules
Link: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=9741e07ece7c247dd65e1aa01e16b683f01c05a8

The Ubuntu kernel cherry-picked the original commit and did not pick up the
silent fix made in the merge commit. Submitting the silent fix as a SAUCE patch
with changelog describing the change.

Note: I know SAUCE patches are bad, but in this scenario, to revert the initial commit and re-apply the fixed version would require us to revert two additional dependency commits, making six patches to review, vs, a one line change in a SAUCE commit that has a real changelog entry.

[Where problems could occur]

The Ubuntu kernel is built with pahole enabled, and requires pahole to be installed as a build dependency. It is extremely unlikely that any users are disabling pahole at build time, apart from linux-bluefield engineers.

If a regression were to occur, engineers would see errors during build time about scripts/pahole-flags.sh not executing properly.

[Other info]

Linus remarked about the issue in the following lkml discussion:

https://lore.kernel<email address hidden>/
https://lore.kernel<email address hidden>/

This was silently Incorporated into the linux-stable commit:

commit 0baced0e0938f2895ceba54038eaf15ed91032e7 5.15.y
From: Jiri Olsa <email address hidden>
Date: Sun, 4 Sep 2022 15:19:00 +0200
Subject: kbuild: Unify options for BTF generation for vmlinux and modules
Link: https://github.com/gregkh/linux/commit/0baced0e0938f2895ceba54038eaf15ed91032e7

[dann frazier (dannf)]

It appears that Linus applied a fix for this directly in a merge commit:
  https://github.com/torvalds/linux/commits/fc02cb2b37fe2cbf1d3334b9f0f0eab9431766c4

When the change with this bug was backported to stable, the fix was squashed. But we appear to have cherry-picked the version from mainline instead of the one from stable which had the bug.

[Ubuntu Kernel Bot (ubuntu-kernel-bot)]

This bug is missing log files that will aid in diagnosing the problem. While running an Ubuntu kernel (not a mainline or third-party kernel) please enter the following command in a terminal window:

apport-collect 2035123

and then change the status of the bug to 'Confirmed'.

If, due to the nature of the issue you have encountered, you are unable to run this command, please add a comment stating that fact and change the bug status to 'Confirmed'.

This change has been made by an automated script, maintained by the Ubuntu Kernel Team.

[Matthew Ruffell (mruffell)]

Patches have been submitted to the kernel team mailing list:

https://lists.ubuntu.com/archives/kernel-team/2023-September/144570.html
https://lists.ubuntu.com/archives/kernel-team/2023-September/144571.html

[Ubuntu Kernel Bot (ubuntu-kernel-bot)]

This bug is awaiting verification that the linux-bluefield/5.15.0-1029.31 kernel in -proposed solves the problem. Please test the kernel and update this bug with the results. If the problem is solved, change the tag 'verification-needed-jammy-linux-bluefield' to 'verification-done-jammy-linux-bluefield'. If the problem still exists, change the tag 'verification-needed-jammy-linux-bluefield' to 'verification-failed-jammy-linux-bluefield'.

If verification is not done by 5 working days from today, this fix will be dropped from the source code, and this bug will be closed.

See https://wiki.ubuntu.com/Testing/EnableProposed for documentation how to enable and use -proposed. Thank you!

[Matthew Ruffell (mruffell)]

Performing verification for Jammy. David Thompson has tested the Ubuntu-bluefield-5.15.0-1029.31 git tag on a arm64 system, and built a kernel successfully, with no more pahole warnings occurring.

Marking verified for linux-bluefield.

[Ubuntu Kernel Bot (ubuntu-kernel-bot)]

This bug is awaiting verification that the linux/5.15.0-90.100 kernel in -proposed solves the problem. Please test the kernel and update this bug with the results. If the problem is solved, change the tag 'verification-needed-jammy-linux' to 'verification-done-jammy-linux'. If the problem still exists, change the tag 'verification-needed-jammy-linux' to 'verification-failed-jammy-linux'.

If verification is not done by 5 working days from today, this fix will be dropped from the source code, and this bug will be closed.

See https://wiki.ubuntu.com/Testing/EnableProposed for documentation how to enable and use -proposed. Thank you!

[Matthew Ruffell (mruffell)]

Performing verification for Jammy. I checked out the Ubuntu-5.15.0-90.100 git tag from the source repository on an arm64 system, and made sure that pahole was removed. I completed a build and looked at the build log, and there were no more pahole warnings.

Marking verified for jammy.

[Ubuntu Kernel Bot (ubuntu-kernel-bot)]

This bug is awaiting verification that the linux-gcp-tcpx/5.15.0-1003.3 kernel in -proposed solves the problem. Please test the kernel and update this bug with the results. If the problem is solved, change the tag 'verification-needed-focal-linux-gcp-tcpx' to 'verification-done-focal-linux-gcp-tcpx'. If the problem still exists, change the tag 'verification-needed-focal-linux-gcp-tcpx' to 'verification-failed-focal-linux-gcp-tcpx'.

If verification is not done by 5 working days from today, this fix will be dropped from the source code, and this bug will be closed.

See https://wiki.ubuntu.com/Testing/EnableProposed for documentation how to enable and use -proposed. Thank you!

[Ubuntu Kernel Bot (ubuntu-kernel-bot)]

This bug is awaiting verification that the linux-azure-fips/5.15.0-1053.61+fips1 kernel in -proposed solves the problem. Please test the kernel and update this bug with the results. If the problem is solved, change the tag 'verification-needed-jammy-linux-azure-fips' to 'verification-done-jammy-linux-azure-fips'. If the problem still exists, change the tag 'verification-needed-jammy-linux-azure-fips' to 'verification-failed-jammy-linux-azure-fips'.

If verification is not done by 5 working days from today, this fix will be dropped from the source code, and this bug will be closed.

See https://wiki.ubuntu.com/Testing/EnableProposed for documentation how to enable and use -proposed. Thank you!

[Launchpad Janitor (janitor)]

This bug was fixed in the package linux - 5.15.0-91.101

---------------
linux (5.15.0-91.101) jammy; urgency=medium

  * jammy/linux: 5.15.0-91.101 -proposed tracker (LP: #2043452)

  * USB bus error after upgrading to proposed kernel on lunar and jammy
    (LP: #2043197)
    - USB: core: Fix oversight in SuperSpeed initialization

linux (5.15.0-90.100) jammy; urgency=medium

  * jammy/linux: 5.15.0-90.100 -proposed tracker (LP: #2041603)

  * CVE-2023-25775
    - RDMA/irdma: Remove irdma_uk_mw_bind()
    - RDMA/irdma: Remove irdma_sc_send_lsmm_nostag()
    - RDMA/irdma: Remove irdma_cqp_up_map_cmd()
    - RDMA/irdma: Remove irdma_get_hw_addr()
    - RDMA/irdma: Make irdma_uk_cq_init() return a void
    - RDMA/irdma: optimize rx path by removing unnecessary copy
    - RDMA/irdma: Remove enum irdma_status_code
    - RDMA/irdma: Remove excess error variables
    - RDMA/irdma: Prevent zero-length STAG registration

  * CVE-2023-39189
    - netfilter: nfnetlink_osf: avoid OOB read

  * SMC stats: Wrong bucket calculation for payload of exactly 4096 bytes
    (LP: #2039575)
    - net/smc: Fix pos miscalculation in statistics

  * CVE-2023-45871
    - igb: set max size RX buffer when store bad packet is enabled

  * CVE-2023-39193
    - netfilter: xt_sctp: validate the flag_info count

  * CVE-2023-39192
    - netfilter: xt_u32: validate user space input

  * CVE-2023-31085
    - ubi: Refuse attaching if mtd's erasesize is 0

  * CVE-2023-5717
    - perf: Disallow mis-matched inherited group reads

  * CVE-2023-5178
    - nvmet-tcp: Fix a possible UAF in queue intialization setup

  * CVE-2023-5158
    - vringh: don't use vringh_kiov_advance() in vringh_iov_xfer()

  * [SRU][J/L/M] UBUNTU: [Packaging] Make WWAN driver a loadable module
    (LP: #2033406)
    - [Packaging] Make WWAN driver loadable modules

  * HP ProBook 450 G8 Notebook fail to wifi test (LP: #2037513)
    - iwlwifi: mvm: Don't fail if PPAG isn't supported
    - wifi: iwlwifi: fw: skip PPAG for JF

  * usbip: error: failed to open /usr/share/hwdata//usb.ids (LP: #2039439)
    - [Packaging] Make linux-tools-common depend on hwdata

  * scripts/pahole-flags.sh change return to exit 0 (LP: #2035123)
    - SAUCE: scripts/pahole-flags.sh change return to exit 0

  * Unable to use nvme drive to install Ubuntu 23.10 (LP: #2040157)
    - misc: rtsx: Fix some platforms can not boot and move the l1ss judgment to
      probe

  * Jammy update: v5.15.131 upstream stable release (LP: #2039610)
    - erofs: ensure that the post-EOF tails are all zeroed
    - ksmbd: fix wrong DataOffset validation of create context
    - ksmbd: replace one-element array with flex-array member in struct
      smb2_ea_info
    - ARM: pxa: remove use of symbol_get()
    - mmc: au1xmmc: force non-modular build and remove symbol_get usage
    - net: enetc: use EXPORT_SYMBOL_GPL for enetc_phc_index
    - rtc: ds1685: use EXPORT_SYMBOL_GPL for ds1685_rtc_poweroff
    - modules: only allow symbol_get of EXPORT_SYMBOL_GPL modules
    - USB: serial: option: add Quectel EM05G variant (0x030e)
    - USB: serial: option: add FOXCONN T99W368/T99W373 product
    - ALSA: usb-audio: Fix init call orders for UAC1
    - usb: dwc3:...

[Ubuntu Kernel Bot (ubuntu-kernel-bot)]

This bug is awaiting verification that the linux-gkeop/5.15.0-1034.40 kernel in -proposed solves the problem. Please test the kernel and update this bug with the results. If the problem is solved, change the tag 'verification-needed-jammy-linux-gkeop' to 'verification-done-jammy-linux-gkeop'. If the problem still exists, change the tag 'verification-needed-jammy-linux-gkeop' to 'verification-failed-jammy-linux-gkeop'.

If verification is not done by 5 working days from today, this fix will be dropped from the source code, and this bug will be closed.

See https://wiki.ubuntu.com/Testing/EnableProposed for documentation how to enable and use -proposed. Thank you!

[Ubuntu Kernel Bot (ubuntu-kernel-bot)]

This bug is awaiting verification that the linux-intel-iotg/5.15.0-1046.52 kernel in -proposed solves the problem. Please test the kernel and update this bug with the results. If the problem is solved, change the tag 'verification-needed-jammy-linux-intel-iotg' to 'verification-done-jammy-linux-intel-iotg'. If the problem still exists, change the tag 'verification-needed-jammy-linux-intel-iotg' to 'verification-failed-jammy-linux-intel-iotg'.

If verification is not done by 5 working days from today, this fix will be dropped from the source code, and this bug will be closed.

See https://wiki.ubuntu.com/Testing/EnableProposed for documentation how to enable and use -proposed. Thank you!

[Ubuntu Kernel Bot (ubuntu-kernel-bot)]

This bug is awaiting verification that the linux-lowlatency/5.15.0-91.101 kernel in -proposed solves the problem. Please test the kernel and update this bug with the results. If the problem is solved, change the tag 'verification-needed-jammy-linux-lowlatency' to 'verification-done-jammy-linux-lowlatency'. If the problem still exists, change the tag 'verification-needed-jammy-linux-lowlatency' to 'verification-failed-jammy-linux-lowlatency'.

If verification is not done by 5 working days from today, this fix will be dropped from the source code, and this bug will be closed.

See https://wiki.ubuntu.com/Testing/EnableProposed for documentation how to enable and use -proposed. Thank you!

[Ubuntu Kernel Bot (ubuntu-kernel-bot)]

This bug is awaiting verification that the linux-gcp-5.15/5.15.0-1048.56~20.04.1 kernel in -proposed solves the problem. Please test the kernel and update this bug with the results. If the problem is solved, change the tag 'verification-needed-focal-linux-gcp-5.15' to 'verification-done-focal-linux-gcp-5.15'. If the problem still exists, change the tag 'verification-needed-focal-linux-gcp-5.15' to 'verification-failed-focal-linux-gcp-5.15'.

If verification is not done by 5 working days from today, this fix will be dropped from the source code, and this bug will be closed.

See https://wiki.ubuntu.com/Testing/EnableProposed for documentation how to enable and use -proposed. Thank you!

[Ubuntu Kernel Bot (ubuntu-kernel-bot)]

This bug is awaiting verification that the linux-nvidia-tegra/5.15.0-1020.20 kernel in -proposed solves the problem. Please test the kernel and update this bug with the results. If the problem is solved, change the tag 'verification-needed-jammy-linux-nvidia-tegra' to 'verification-done-jammy-linux-nvidia-tegra'. If the problem still exists, change the tag 'verification-needed-jammy-linux-nvidia-tegra' to 'verification-failed-jammy-linux-nvidia-tegra'.

If verification is not done by 5 working days from today, this fix will be dropped from the source code, and this bug will be closed.

See https://wiki.ubuntu.com/Testing/EnableProposed for documentation how to enable and use -proposed. Thank you!

[Ubuntu Kernel Bot (ubuntu-kernel-bot)]

This bug is awaiting verification that the linux-nvidia-tegra-igx/5.15.0-1007.7 kernel in -proposed solves the problem. Please test the kernel and update this bug with the results. If the problem is solved, change the tag 'verification-needed-jammy-linux-nvidia-tegra-igx' to 'verification-done-jammy-linux-nvidia-tegra-igx'. If the problem still exists, change the tag 'verification-needed-jammy-linux-nvidia-tegra-igx' to 'verification-failed-jammy-linux-nvidia-tegra-igx'.

If verification is not done by 5 working days from today, this fix will be dropped from the source code, and this bug will be closed.

See https://wiki.ubuntu.com/Testing/EnableProposed for documentation how to enable and use -proposed. Thank you!

[Ubuntu Kernel Bot (ubuntu-kernel-bot)]

This bug is awaiting verification that the linux-intel-iotg-5.15/5.15.0-1046.52~20.04.1 kernel in -proposed solves the problem. Please test the kernel and update this bug with the results. If the problem is solved, change the tag 'verification-needed-focal-linux-intel-iotg-5.15' to 'verification-done-focal-linux-intel-iotg-5.15'. If the problem still exists, change the tag 'verification-needed-focal-linux-intel-iotg-5.15' to 'verification-failed-focal-linux-intel-iotg-5.15'.

If verification is not done by 5 working days from today, this fix will be dropped from the source code, and this bug will be closed.

See https://wiki.ubuntu.com/Testing/EnableProposed for documentation how to enable and use -proposed. Thank you!

[Ubuntu Kernel Bot (ubuntu-kernel-bot)]

This bug is awaiting verification that the linux-nvidia-tegra-5.15/5.15.0-1020.20~20.04.1 kernel in -proposed solves the problem. Please test the kernel and update this bug with the results. If the problem is solved, change the tag 'verification-needed-focal-linux-nvidia-tegra-5.15' to 'verification-done-focal-linux-nvidia-tegra-5.15'. If the problem still exists, change the tag 'verification-needed-focal-linux-nvidia-tegra-5.15' to 'verification-failed-focal-linux-nvidia-tegra-5.15'.

If verification is not done by 5 working days from today, this fix will be dropped from the source code, and this bug will be closed.

See https://wiki.ubuntu.com/Testing/EnableProposed for documentation how to enable and use -proposed. Thank you!

[Ubuntu Kernel Bot (ubuntu-kernel-bot)]

This bug is awaiting verification that the linux-mtk/5.15.0-1030.34 kernel in -proposed solves the problem. Please test the kernel and update this bug with the results. If the problem is solved, change the tag 'verification-needed-jammy-linux-mtk' to 'verification-done-jammy-linux-mtk'. If the problem still exists, change the tag 'verification-needed-jammy-linux-mtk' to 'verification-failed-jammy-linux-mtk'.

If verification is not done by 5 working days from today, this fix will be dropped from the source code, and this bug will be closed.

See https://wiki.ubuntu.com/Testing/EnableProposed for documentation how to enable and use -proposed. Thank you!