The IMA_MEASURE_PCR_IDX option is currently not visible in the kconfig frontend, so it always uses its default, 10. This means that the 'range 8 14' is dead code, and users are unable to specify the pcr index value.
In a previous discussion, Mimi explained that users should be able to use this config option to specify the pcr index. [1] Let's add a prompt for users to specify the pcr index, when EXPERT is enabled. This dead range was found by kconfirm, a static analysis tool for Kconfig. Link: https://lore.kernel.org/all/[email protected]/T/#mc4efa2491b4937eb7c9e532c29ffba516a70e662 [1] Signed-off-by: Julian Braha <[email protected]> --- Changes since v1: - updated help text to recommend using the default of 10 v1: https://lore.kernel.org/all/[email protected]/ --- security/integrity/ima/Kconfig | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/security/integrity/ima/Kconfig b/security/integrity/ima/Kconfig index b3a9f86809b0..72654cf797cd 100644 --- a/security/integrity/ima/Kconfig +++ b/security/integrity/ima/Kconfig @@ -46,12 +46,16 @@ config IMA_KEXEC config IMA_MEASURE_PCR_IDX int + prompt "PCR Index for Aggregate" if EXPERT range 8 14 default 10 help IMA_MEASURE_PCR_IDX determines the TPM PCR register index that IMA uses to maintain the integrity aggregate of the - measurement list. If unsure, use the default 10. + measurement list. Most attestation tooling expects PCR 10. + + The default is almost always what you want. Only change this + if you know what you are doing. config IMA_LSM_RULES bool -- 2.55.0
