From: Laura Abbott Date: Wed, 16 Aug 2017 16:14:57 -0700 Message-Id: <20170816231458.2299-2-labbott@redhat.com> In-Reply-To: <20170816231458.2299-1-labbott@redhat.com> References: <20170816231458.2299-1-labbott@redhat.com> Subject: [kernel-hardening] [PATCHv3 1/2] init: Move stack canary initialization after setup_arch To: Kees Cook Cc: Laura Abbott , kernel-hardening@lists.openwall.com, linux-kernel@vger.kernel.org, linux-mm@kvack.org, Andrew Morton , Daniel Micay , Laura Abbott List-ID: From: Laura Abbott Stack canary intialization involves getting a random number. Getting this random number may involve accessing caches or other architectural specific features which are not available until after the architecture is setup. Move the stack canary initialization later to accomodate this. Acked-by: Kees Cook Signed-off-by: Laura Abbott Signed-off-by: Laura Abbott --- v3: Ack from Kees --- init/main.c | 11 +++++------ 1 file changed, 5 insertions(+), 6 deletions(-) diff --git a/init/main.c b/init/main.c index 052481fbe363..21d599eaad06 100644 --- a/init/main.c +++ b/init/main.c @@ -515,12 +515,6 @@ asmlinkage __visible void __init start_kernel(void) smp_setup_processor_id(); debug_objects_early_init(); - /* - * Set up the initial canary ASAP: - */ - add_latent_entropy(); - boot_init_stack_canary(); - cgroup_init_early(); local_irq_disable(); @@ -534,6 +528,11 @@ asmlinkage __visible void __init start_kernel(void) page_address_init(); pr_notice("%s", linux_banner); setup_arch(&command_line); + /* + * Set up the the initial canary and entropy after arch + */ + add_latent_entropy(); + boot_init_stack_canary(); mm_init_cpumask(&init_mm); setup_command_line(command_line); setup_nr_cpu_ids(); -- 2.13.0