linux-kernel - [RFC KVM 01/27] kernel: Export memory-management symbols required for KVM address space isolation

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-Id: <1557758315-12667-2-git-send-email-alexandre.chartre@oracle.com>
Date:   Mon, 13 May 2019 16:38:09 +0200
From:   Alexandre Chartre <alexandre.chartre@...cle.com>
To:     pbonzini@...hat.com, rkrcmar@...hat.com, tglx@...utronix.de,
        mingo@...hat.com, bp@...en8.de, hpa@...or.com,
        dave.hansen@...ux.intel.com, luto@...nel.org, peterz@...radead.org,
        kvm@...r.kernel.org, x86@...nel.org, linux-mm@...ck.org,
        linux-kernel@...r.kernel.org
Cc:     konrad.wilk@...cle.com, jan.setjeeilers@...cle.com,
        liran.alon@...cle.com, jwadams@...gle.com,
        alexandre.chartre@...cle.com
Subject: [RFC KVM 01/27] kernel: Export memory-management symbols required for KVM address space isolation

From: Liran Alon <liran.alon@...cle.com>

Export symbols needed to create, manage, populate and switch
a mm from a kernel module (kvm in this case).

This is a hacky way for now to start.
This should be changed to some suitable memory-management API.

Signed-off-by: Liran Alon <liran.alon@...cle.com>
Signed-off-by: Alexandre Chartre <alexandre.chartre@...cle.com>
---
 arch/x86/kernel/ldt.c |    1 +
 arch/x86/mm/tlb.c     |    3 ++-
 mm/memory.c           |    5 +++++
 3 files changed, 8 insertions(+), 1 deletions(-)

diff --git a/arch/x86/kernel/ldt.c b/arch/x86/kernel/ldt.c
index b2463fc..19a86e0 100644
--- a/arch/x86/kernel/ldt.c
+++ b/arch/x86/kernel/ldt.c
@@ -401,6 +401,7 @@ void destroy_context_ldt(struct mm_struct *mm)
 	free_ldt_struct(mm->context.ldt);
 	mm->context.ldt = NULL;
 }
+EXPORT_SYMBOL_GPL(destroy_context_ldt);
 
 void ldt_arch_exit_mmap(struct mm_struct *mm)
 {
diff --git a/arch/x86/mm/tlb.c b/arch/x86/mm/tlb.c
index 7f61431..a4db7f5 100644
--- a/arch/x86/mm/tlb.c
+++ b/arch/x86/mm/tlb.c
@@ -70,7 +70,7 @@ static void clear_asid_other(void)
 }
 
 atomic64_t last_mm_ctx_id = ATOMIC64_INIT(1);
-
+EXPORT_SYMBOL_GPL(last_mm_ctx_id);
 
 static void choose_new_asid(struct mm_struct *next, u64 next_tlb_gen,
 			    u16 *new_asid, bool *need_flush)
@@ -159,6 +159,7 @@ void switch_mm(struct mm_struct *prev, struct mm_struct *next,
 	switch_mm_irqs_off(prev, next, tsk);
 	local_irq_restore(flags);
 }
+EXPORT_SYMBOL_GPL(switch_mm);
 
 static void sync_current_stack_to_mm(struct mm_struct *mm)
 {
diff --git a/mm/memory.c b/mm/memory.c
index 36aac68..ede9335 100644
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -434,6 +434,7 @@ int __pte_alloc(struct mm_struct *mm, pmd_t *pmd)
 		pte_free(mm, new);
 	return 0;
 }
+EXPORT_SYMBOL_GPL(__pte_alloc);
 
 int __pte_alloc_kernel(pmd_t *pmd)
 {
@@ -453,6 +454,7 @@ int __pte_alloc_kernel(pmd_t *pmd)
 		pte_free_kernel(&init_mm, new);
 	return 0;
 }
+EXPORT_SYMBOL_GPL(__pte_alloc_kernel);
 
 static inline void init_rss_vec(int *rss)
 {
@@ -4007,6 +4009,7 @@ int __p4d_alloc(struct mm_struct *mm, pgd_t *pgd, unsigned long address)
 	spin_unlock(&mm->page_table_lock);
 	return 0;
 }
+EXPORT_SYMBOL_GPL(__p4d_alloc);
 #endif /* __PAGETABLE_P4D_FOLDED */
 
 #ifndef __PAGETABLE_PUD_FOLDED
@@ -4039,6 +4042,7 @@ int __pud_alloc(struct mm_struct *mm, p4d_t *p4d, unsigned long address)
 	spin_unlock(&mm->page_table_lock);
 	return 0;
 }
+EXPORT_SYMBOL_GPL(__pud_alloc);
 #endif /* __PAGETABLE_PUD_FOLDED */
 
 #ifndef __PAGETABLE_PMD_FOLDED
@@ -4072,6 +4076,7 @@ int __pmd_alloc(struct mm_struct *mm, pud_t *pud, unsigned long address)
 	spin_unlock(ptl);
 	return 0;
 }
+EXPORT_SYMBOL_GPL(__pmd_alloc);
 #endif /* __PAGETABLE_PMD_FOLDED */
 
 static int __follow_pte_pmd(struct mm_struct *mm, unsigned long address,
-- 
1.7.1