Add two parameter to specify how many times a kexec kernel can be loaded. These parameter allow hardening the system. While we are at it, fix a documentation issue and refactor some code. To: Jonathan Corbet <corbet@xxxxxxx> To: Eric Biederman <ebiederm@xxxxxxxxxxxx> Cc: linux-doc@xxxxxxxxxxxxxxx Cc: linux-kernel@xxxxxxxxxxxxxxx Cc: kexec@xxxxxxxxxxxxxxxxxxx Cc: Joel Fernandes (Google) <joel@xxxxxxxxxxxxxxxxx> Cc: Sergey Senozhatsky <senozhatsky@xxxxxxxxxxxx> Cc: Steven Rostedt <rostedt@xxxxxxxxxxx> Cc: Ross Zwisler <zwisler@xxxxxxxxxx> To: Philipp Rudo <prudo@xxxxxxxxxx> To: Guilherme G. Piccoli <gpiccoli@xxxxxxxxxx> Signed-off-by: Ricardo Ribalda <ribalda@xxxxxxxxxxxx> --- Changes in v5: - Remove maxlen from ctl_table. Thanks Steven! - Link to v4: https://lore.kernel.org/r/20221114-disable-kexec-reset-v4-0-ab809c8d988c@xxxxxxxxxxxx Changes in v4 (Thanks Steven!): - Uses sysctl instead or module_parameters - Pass image type instead of boolean to permitted - Fix typo on flag handling - Return -EINVAL for values that does not change the current value. - Link to v3: https://lore.kernel.org/r/20221114-disable-kexec-reset-v3-0-4ef4e929adf6@xxxxxxxxxxxx Changes in v3: - s/paramter/parameter/ Thanks Ghilherme! - s/permited/permitted/ Thanks Joel! - Link to v2: https://lore.kernel.org/r/20221114-disable-kexec-reset-v2-0-c498313c1bb5@xxxxxxxxxxxx Changes in v2: - Instead of kexec_reboot_disabled, add two new counters (Thanks Philipp!) - Link to v1: https://lore.kernel.org/r/20221114-disable-kexec-reset-v1-0-fb51d20cf871@xxxxxxxxxxxx --- Ricardo Ribalda (3): Documentation: sysctl: Correct kexec_load_disabled kexec: Factor out kexec_load_permitted kexec: Introduce sysctl parameters kexec_load_limit_* Documentation/admin-guide/sysctl/kernel.rst | 25 +++++++- include/linux/kexec.h | 3 +- kernel/kexec.c | 4 +- kernel/kexec_core.c | 94 ++++++++++++++++++++++++++++- kernel/kexec_file.c | 11 ++-- 5 files changed, 127 insertions(+), 10 deletions(-) --- base-commit: 479174d402bcf60789106eedc4def3957c060bad change-id: 20221114-disable-kexec-reset-19b7e117338f Best regards, -- Ricardo Ribalda <ribalda@xxxxxxxxxxxx>
