From c10e83f598d08046dd1ebc8360d4bb12d802d51b Mon Sep 17 00:00:00 2001
From: Thomas Gleixner <tglx@linutronix.de>
Date: Thu, 14 Dec 2017 12:27:29 +0100
Subject: [PATCH] arch, mm: Allow arch_dup_mmap() to fail
In order to sanitize the LDT initialization on x86 arch_dup_mmap() must be
allowed to fail. Fix up all instances.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Andy Lutomirsky <luto@kernel.org>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Borislav Petkov <bpetkov@suse.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: David Laight <David.Laight@aculab.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Eduardo Valentin <eduval@amazon.com>
Cc: Greg KH <gregkh@linuxfoundation.org>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Will Deacon <will.deacon@arm.com>
Cc: aliguori@amazon.com
Cc: dan.j.williams@intel.com
Cc: hughd@google.com
Cc: keescook@google.com
Cc: kirill.shutemov@linux.intel.com
Cc: linux-mm@kvack.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
---
arch/powerpc/include/asm/mmu_context.h | 5 +++--
arch/um/include/asm/mmu_context.h | 3 ++-
arch/unicore32/include/asm/mmu_context.h | 5 +++--
arch/x86/include/asm/mmu_context.h | 4 ++--
include/asm-generic/mm_hooks.h | 5 +++--
kernel/fork.c | 3 +--
6 files changed, 14 insertions(+), 11 deletions(-)
diff --git a/arch/powerpc/include/asm/mmu_context.h b/arch/powerpc/include/asm/mmu_context.h
index 492d8140a395..44fdf4786638 100644
--- a/arch/powerpc/include/asm/mmu_context.h
+++ b/arch/powerpc/include/asm/mmu_context.h
@@ -114,9 +114,10 @@ static inline void enter_lazy_tlb(struct mm_struct *mm,
#endif
}
-static inline void arch_dup_mmap(struct mm_struct *oldmm,
- struct mm_struct *mm)
+static inline int arch_dup_mmap(struct mm_struct *oldmm,
+ struct mm_struct *mm)
{
+ return 0;
}
static inline void arch_exit_mmap(struct mm_struct *mm)
diff --git a/arch/um/include/asm/mmu_context.h b/arch/um/include/asm/mmu_context.h
index b668e351fd6c..fca34b2177e2 100644
--- a/arch/um/include/asm/mmu_context.h
+++ b/arch/um/include/asm/mmu_context.h
@@ -15,9 +15,10 @@ extern void uml_setup_stubs(struct mm_struct *mm);
/*
* Needed since we do not use the asm-generic/mm_hooks.h:
*/
-static inline void arch_dup_mmap(struct mm_struct *oldmm, struct mm_struct *mm)
+static inline int arch_dup_mmap(struct mm_struct *oldmm, struct mm_struct *mm)
{
uml_setup_stubs(mm);
+ return 0;
}
extern void arch_exit_mmap(struct mm_struct *mm);
static inline void arch_unmap(struct mm_struct *mm,
diff --git a/arch/unicore32/include/asm/mmu_context.h b/arch/unicore32/include/asm/mmu_context.h
index 59b06b48f27d..5c205a9cb5a6 100644
--- a/arch/unicore32/include/asm/mmu_context.h
+++ b/arch/unicore32/include/asm/mmu_context.h
@@ -81,9 +81,10 @@ do { \
} \
} while (0)
-static inline void arch_dup_mmap(struct mm_struct *oldmm,
- struct mm_struct *mm)
+static inline int arch_dup_mmap(struct mm_struct *oldmm,
+ struct mm_struct *mm)
{
+ return 0;
}
static inline void arch_unmap(struct mm_struct *mm,
diff --git a/arch/x86/include/asm/mmu_context.h b/arch/x86/include/asm/mmu_context.h
index 6d16d15d09a0..c76162439c8a 100644
--- a/arch/x86/include/asm/mmu_context.h
+++ b/arch/x86/include/asm/mmu_context.h
@@ -176,10 +176,10 @@ do { \
} while (0)
#endif
-static inline void arch_dup_mmap(struct mm_struct *oldmm,
- struct mm_struct *mm)
+static inline int arch_dup_mmap(struct mm_struct *oldmm, struct mm_struct *mm)
{
paravirt_arch_dup_mmap(oldmm, mm);
+ return 0;
}
static inline void arch_exit_mmap(struct mm_struct *mm)
diff --git a/include/asm-generic/mm_hooks.h b/include/asm-generic/mm_hooks.h
index ea189d88a3cc..8ac4e68a12f0 100644
--- a/include/asm-generic/mm_hooks.h
+++ b/include/asm-generic/mm_hooks.h
@@ -7,9 +7,10 @@
#ifndef _ASM_GENERIC_MM_HOOKS_H
#define _ASM_GENERIC_MM_HOOKS_H
-static inline void arch_dup_mmap(struct mm_struct *oldmm,
- struct mm_struct *mm)
+static inline int arch_dup_mmap(struct mm_struct *oldmm,
+ struct mm_struct *mm)
{
+ return 0;
}
static inline void arch_exit_mmap(struct mm_struct *mm)
diff --git a/kernel/fork.c b/kernel/fork.c
index 07cc743698d3..500ce64517d9 100644
--- a/kernel/fork.c
+++ b/kernel/fork.c
@@ -721,8 +721,7 @@ static __latent_entropy int dup_mmap(struct mm_struct *mm,
goto out;
}
/* a new mm has just been created */
- arch_dup_mmap(oldmm, mm);
- retval = 0;
+ retval = arch_dup_mmap(oldmm, mm);
out:
up_write(&mm->mmap_sem);
flush_tlb_mm(oldmm);
--
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