From 628d06a48f57c36abdc2a024930212e654a501b7 Mon Sep 17 00:00:00 2001 From: Sami Tolvanen Date: Mon, 27 Apr 2020 09:00:08 -0700 Subject: scs: Add page accounting for shadow call stack allocations This change adds accounting for the memory allocated for shadow stacks. Signed-off-by: Sami Tolvanen Reviewed-by: Kees Cook Acked-by: Will Deacon Signed-off-by: Will Deacon --- kernel/scs.c | 15 +++++++++++++++ 1 file changed, 15 insertions(+) (limited to 'kernel/scs.c') diff --git a/kernel/scs.c b/kernel/scs.c index 38f8f31c9451..6d2f983ac54e 100644 --- a/kernel/scs.c +++ b/kernel/scs.c @@ -6,8 +6,10 @@ */ #include +#include #include #include +#include #include static struct kmem_cache *scs_cache; @@ -40,6 +42,17 @@ void __init scs_init(void) scs_cache = kmem_cache_create("scs_cache", SCS_SIZE, 0, 0, NULL); } +static struct page *__scs_page(struct task_struct *tsk) +{ + return virt_to_page(task_scs(tsk)); +} + +static void scs_account(struct task_struct *tsk, int account) +{ + mod_zone_page_state(page_zone(__scs_page(tsk)), NR_KERNEL_SCS_KB, + account * (SCS_SIZE / 1024)); +} + int scs_prepare(struct task_struct *tsk, int node) { void *s = scs_alloc(node); @@ -49,6 +62,7 @@ int scs_prepare(struct task_struct *tsk, int node) task_scs(tsk) = s; task_scs_offset(tsk) = 0; + scs_account(tsk, 1); return 0; } @@ -61,5 +75,6 @@ void scs_release(struct task_struct *tsk) return; WARN(scs_corrupted(tsk), "corrupted shadow stack detected when freeing task\n"); + scs_account(tsk, -1); scs_free(s); } -- cgit v1.2.3