Commit Graph

9 Commits

Author SHA1 Message Date
Vasily Gorbik
50f909db8f zipl/boot: Fix stage3 secure boot trailer placement
The stage3 linker script places .sb.trailer so that it must end at
COMMAND_LINE_EXTRA. The current script derives the start address from
SIZEOF(.sb.trailer) before the section is emitted:

  . = COMMAND_LINE_EXTRA - SIZEOF(.sb.trailer);

With binutils older than 2.39 before commit 648f6099d4dc ("-z relro
relaxation and ld script SIZEOF") this can result in .sb.trailer being
placed at COMMAND_LINE_EXTRA instead, moving the trailer into the
following area and breaking the expected layout.

The trailer has a fixed size, so use an explicit constant for the
placement calculation and keep the ASSERT to verify the final section
size. This makes the placement deterministic again.

Fixes: a1126352ec ("zipl/boot: Improve linker scripts")
Reviewed-by: Marc Hartmayer <marc@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Jan Höppner <hoeppner@linux.ibm.com>
2026-04-10 11:21:23 +02:00
Marc Hartmayer
a1126352ec zipl/boot: Improve linker scripts
Output all text input sections into one text section and map all input
sections .bss.* .text.*, .rodata.*, and .data.* as it's done by the
default linker script [1]. In addition, make the linker script easier to
read by replacing the magic value of 32 with 'SIZEOF(.sb.trailer)'.

[1] Check the output of 'ld --verbose'.

Reviewed-by: Mikhail Zaslonko <zaslonko@linux.ibm.com>
Reviewed-by: Stefan Haberland <sth@linux.ibm.com>
Signed-off-by: Marc Hartmayer <mhartmay@linux.ibm.com>
Signed-off-by: Jan Höppner <hoeppner@linux.ibm.com>
2025-11-07 14:34:48 +01:00
Frank Heimes
6fc450f696 (genprotimg|zipl)/boot: discard .note.package ELF section to save memory
The .note.package [1] section is not used by the zipl/genprotimg bootloaders,
therefore discard them via linker script.

This fix solves the error:
 /usr/bin/ld: Heap section doesn't conform to the described memory layout
 collect2: error: ld returned 1 exit status
 make[4]: *** [Makefile:77: stage3a.elf] Error 1
 make[4]: Leaving directory '/<>/genprotimg/boot'
 make[3]: *** [Makefile:20: all-recursive] Error 1
 make[3]: Leaving directory '/<>/genprotimg'
 make[2]: *** [Makefile:56: genprotimg] Error 2

[1] https://systemd.io/ELF_PACKAGE_METADATA/

Fixes: https://github.com/ibm-s390-linux/s390-tools/issues/174
Closes: https://github.com/ibm-s390-linux/s390-tools/pull/176
[seiden@linux.ibm.com: Add/edit fixes tags]
Signed-off-by: Marc Hartmayer <mhartmay@linux.ibm.com>
Signed-off-by: Frank Heimes <frank.heimes@canonical.com>
Reviewed-by: Steffen Eiden <seiden@linux.ibm.com>
Signed-off-by: Steffen Eiden <seiden@linux.ibm.com>
Signed-off-by: Jan Höppner <hoeppner@linux.ibm.com>
2024-09-13 19:14:16 +02:00
Marc Hartmayer
4bed503aa7 zipl/boot: disable build-id
Disable the build-id since it was never used. Adapt the linker scripts
accordingly.

Reviewed-by: Steffen Eiden <seiden@linux.ibm.com>
Reviewed-by: Stefan Haberland <sth@linux.ibm.com>
Signed-off-by: Marc Hartmayer <mhartmay@linux.ibm.com>
Signed-off-by: Jan Höppner <hoeppner@linux.ibm.com>
2023-02-13 22:18:49 +01:00
Marc Hartmayer
3d168fac14 zipl/boot: declare that no executable stack is required
Normally, `gcc` takes care of adding the `GNU_STACK` marking except for
assembly code. Therefore, let's add the marking manually. Discard the
`.note.GNU-stack` section in the linker script since it's just a
"message" from the compiler to the linker. This fixes the linker
warning:

ld: warning: entry.o: missing .note.GNU-stack section implies executable stack

Acked-by: Eduard Shishkin <edward6@linux.ibm.com>
Reviewed-by: Stefan Haberland <sth@linux.ibm.com>
Signed-off-by: Marc Hartmayer <mhartmay@linux.ibm.com>
Signed-off-by: Jan Höppner <hoeppner@linux.ibm.com>
2023-02-13 22:18:49 +01:00
Marc Hartmayer
746a703079 zipl/boot: discard .eh_frame and .interp input sections
The ELF section `.eh_frame` is used for frame unwinding during, for
example, exception handling and the section `.interp` is used by the
program interpreter. [1] Since no frame unwinding nor a program
interpreter is used for the bootloaders we can discard these input
section.

The content of the (exec|bin) files don't change after this change.

[1] https://refspecs.linuxfoundation.org/LSB_1.2.0/gLSB/specialsections.html

Reviewed-by: Stefan Haberland <sth@linux.ibm.com>
Signed-off-by: Marc Hartmayer <mhartmay@linux.ibm.com>
Signed-off-by: Jan Höppner <hoeppner@linux.ibm.com>
2023-02-13 22:18:49 +01:00
Peter Oberparleiter
5768d55a08 zipl/boot: add secure boot trailer
This patch enhances the zipl stage3 loader image adding a trailer as
required for secure boot by future firmware versions.

Note: with the change in this patch the padding via objcopy command line
options is replaced by padding via linker script directives with the
same effect.

Signed-off-by: Peter Oberparleiter <oberpar@linux.ibm.com>
Signed-off-by: Jan Höppner <hoeppner@linux.ibm.com>
2022-10-22 20:27:16 +02:00
Marc Hartmayer
2e6cf81c2a zipl/boot: stage3.lds.S: put notes section explicitly at the end
...otherwise `.note.gnu.build-id` will be put at 0x0 (location for s390x
lowcore) if the linker option `--build-id` is used (which is the default
if gcc is used for linking).

Signed-off-by: Marc Hartmayer <mhartmay@linux.ibm.com>
Reviewed-by: Steffen Eiden <seiden@linux.ibm.com>
Reviewed-by: Stefan Haberland <sth@linux.ibm.com>
Signed-off-by: Jan Höppner <hoeppner@linux.ibm.com>
2022-06-03 18:40:36 +02:00
Marc Hartmayer
19f747847f zipl/boot: use C pre-processor for linker script generation
Use C pre-processor for linker script generation and refactor some
constants. This allows the usage of the constants in our "linker
scripts" `*.lds.S` (actually, these are assembler files, so we can
make us of the C pre-processor and its capabilities).

While at it, enforce the described memory layout in the generated
linker script.

Reviewed-by: Stefan Haberland <sth@linux.ibm.com>
Reviewed-by: Philipp Rudo <prudo@linux.ibm.com>
Signed-off-by: Marc Hartmayer <mhartmay@linux.ibm.com>
Signed-off-by: Jan Höppner <hoeppner@linux.ibm.com>
2020-05-06 17:36:39 +02:00