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-rw-r--r--arch/powerpc/include/asm/mmu_context.h3
-rw-r--r--arch/s390/include/asm/mmu_context.h3
-rw-r--r--arch/unicore32/include/asm/mmu_context.h3
-rw-r--r--arch/x86/include/asm/mmu_context.h5
-rw-r--r--drivers/iommu/amd_iommu_v2.c1
-rw-r--r--include/asm-generic/mm_hooks.h3
-rw-r--r--include/linux/mm.h1
-rw-r--r--mm/gup.c15
-rw-r--r--mm/ksm.c10
-rw-r--r--mm/memory.c3
10 files changed, 33 insertions, 14 deletions
diff --git a/arch/powerpc/include/asm/mmu_context.h b/arch/powerpc/include/asm/mmu_context.h
index a0f1838c8e78..df9bf3ed025b 100644
--- a/arch/powerpc/include/asm/mmu_context.h
+++ b/arch/powerpc/include/asm/mmu_context.h
@@ -148,7 +148,8 @@ static inline void arch_bprm_mm_init(struct mm_struct *mm,
{
}
-static inline bool arch_vma_access_permitted(struct vm_area_struct *vma, bool write)
+static inline bool arch_vma_access_permitted(struct vm_area_struct *vma,
+ bool write, bool foreign)
{
/* by default, allow everything */
return true;
diff --git a/arch/s390/include/asm/mmu_context.h b/arch/s390/include/asm/mmu_context.h
index 2627b338382c..8906600922ce 100644
--- a/arch/s390/include/asm/mmu_context.h
+++ b/arch/s390/include/asm/mmu_context.h
@@ -130,7 +130,8 @@ static inline void arch_bprm_mm_init(struct mm_struct *mm,
{
}
-static inline bool arch_vma_access_permitted(struct vm_area_struct *vma, bool write)
+static inline bool arch_vma_access_permitted(struct vm_area_struct *vma,
+ bool write, bool foreign)
{
/* by default, allow everything */
return true;
diff --git a/arch/unicore32/include/asm/mmu_context.h b/arch/unicore32/include/asm/mmu_context.h
index 3133f947ade2..e35632ef23c7 100644
--- a/arch/unicore32/include/asm/mmu_context.h
+++ b/arch/unicore32/include/asm/mmu_context.h
@@ -97,7 +97,8 @@ static inline void arch_bprm_mm_init(struct mm_struct *mm,
{
}
-static inline bool arch_vma_access_permitted(struct vm_area_struct *vma, bool write)
+static inline bool arch_vma_access_permitted(struct vm_area_struct *vma,
+ bool write, bool foreign)
{
/* by default, allow everything */
return true;
diff --git a/arch/x86/include/asm/mmu_context.h b/arch/x86/include/asm/mmu_context.h
index 19036cdbed8f..b4d939a17e60 100644
--- a/arch/x86/include/asm/mmu_context.h
+++ b/arch/x86/include/asm/mmu_context.h
@@ -322,10 +322,11 @@ static inline bool vma_is_foreign(struct vm_area_struct *vma)
return false;
}
-static inline bool arch_vma_access_permitted(struct vm_area_struct *vma, bool write)
+static inline bool arch_vma_access_permitted(struct vm_area_struct *vma,
+ bool write, bool foreign)
{
/* allow access if the VMA is not one from this process */
- if (vma_is_foreign(vma))
+ if (foreign || vma_is_foreign(vma))
return true;
return __pkru_allows_pkey(vma_pkey(vma), write);
}
diff --git a/drivers/iommu/amd_iommu_v2.c b/drivers/iommu/amd_iommu_v2.c
index c865737326e1..56999d2fac07 100644
--- a/drivers/iommu/amd_iommu_v2.c
+++ b/drivers/iommu/amd_iommu_v2.c
@@ -526,6 +526,7 @@ static void do_fault(struct work_struct *work)
flags |= FAULT_FLAG_USER;
if (fault->flags & PPR_FAULT_WRITE)
flags |= FAULT_FLAG_WRITE;
+ flags |= FAULT_FLAG_REMOTE;
down_read(&mm->mmap_sem);
vma = find_extend_vma(mm, address);
diff --git a/include/asm-generic/mm_hooks.h b/include/asm-generic/mm_hooks.h
index c1fc5af3c384..d5c9633bd955 100644
--- a/include/asm-generic/mm_hooks.h
+++ b/include/asm-generic/mm_hooks.h
@@ -26,7 +26,8 @@ static inline void arch_bprm_mm_init(struct mm_struct *mm,
{
}
-static inline bool arch_vma_access_permitted(struct vm_area_struct *vma, bool write)
+static inline bool arch_vma_access_permitted(struct vm_area_struct *vma,
+ bool write, bool foreign)
{
/* by default, allow everything */
return true;
diff --git a/include/linux/mm.h b/include/linux/mm.h
index 3056369bab1d..2aaa0f0d67ea 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -251,6 +251,7 @@ extern pgprot_t protection_map[16];
#define FAULT_FLAG_KILLABLE 0x10 /* The fault task is in SIGKILL killable region */
#define FAULT_FLAG_TRIED 0x20 /* Second try */
#define FAULT_FLAG_USER 0x40 /* The fault originated in userspace */
+#define FAULT_FLAG_REMOTE 0x80 /* faulting for non current tsk/mm */
/*
* vm_fault is filled by the the pagefault handler and passed to the vma's
diff --git a/mm/gup.c b/mm/gup.c
index e0f5f3574d16..d276760163b3 100644
--- a/mm/gup.c
+++ b/mm/gup.c
@@ -365,6 +365,8 @@ static int faultin_page(struct task_struct *tsk, struct vm_area_struct *vma,
return -ENOENT;
if (*flags & FOLL_WRITE)
fault_flags |= FAULT_FLAG_WRITE;
+ if (*flags & FOLL_REMOTE)
+ fault_flags |= FAULT_FLAG_REMOTE;
if (nonblocking)
fault_flags |= FAULT_FLAG_ALLOW_RETRY;
if (*flags & FOLL_NOWAIT)
@@ -415,11 +417,13 @@ static int faultin_page(struct task_struct *tsk, struct vm_area_struct *vma,
static int check_vma_flags(struct vm_area_struct *vma, unsigned long gup_flags)
{
vm_flags_t vm_flags = vma->vm_flags;
+ int write = (gup_flags & FOLL_WRITE);
+ int foreign = (gup_flags & FOLL_REMOTE);
if (vm_flags & (VM_IO | VM_PFNMAP))
return -EFAULT;
- if (gup_flags & FOLL_WRITE) {
+ if (write) {
if (!(vm_flags & VM_WRITE)) {
if (!(gup_flags & FOLL_FORCE))
return -EFAULT;
@@ -445,7 +449,7 @@ static int check_vma_flags(struct vm_area_struct *vma, unsigned long gup_flags)
if (!(vm_flags & VM_MAYREAD))
return -EFAULT;
}
- if (!arch_vma_access_permitted(vma, (gup_flags & FOLL_WRITE)))
+ if (!arch_vma_access_permitted(vma, write, foreign))
return -EFAULT;
return 0;
}
@@ -615,7 +619,8 @@ EXPORT_SYMBOL(__get_user_pages);
bool vma_permits_fault(struct vm_area_struct *vma, unsigned int fault_flags)
{
- bool write = !!(fault_flags & FAULT_FLAG_WRITE);
+ bool write = !!(fault_flags & FAULT_FLAG_WRITE);
+ bool foreign = !!(fault_flags & FAULT_FLAG_REMOTE);
vm_flags_t vm_flags = write ? VM_WRITE : VM_READ;
if (!(vm_flags & vma->vm_flags))
@@ -623,9 +628,9 @@ bool vma_permits_fault(struct vm_area_struct *vma, unsigned int fault_flags)
/*
* The architecture might have a hardware protection
- * mechanism other than read/write that can deny access
+ * mechanism other than read/write that can deny access.
*/
- if (!arch_vma_access_permitted(vma, write))
+ if (!arch_vma_access_permitted(vma, write, foreign))
return false;
return true;
diff --git a/mm/ksm.c b/mm/ksm.c
index c2013f638d11..b99e828172f6 100644
--- a/mm/ksm.c
+++ b/mm/ksm.c
@@ -359,6 +359,10 @@ static inline bool ksm_test_exit(struct mm_struct *mm)
* in case the application has unmapped and remapped mm,addr meanwhile.
* Could a ksm page appear anywhere else? Actually yes, in a VM_PFNMAP
* mmap of /dev/mem or /dev/kmem, where we would not want to touch it.
+ *
+ * FAULT_FLAG/FOLL_REMOTE are because we do this outside the context
+ * of the process that owns 'vma'. We also do not want to enforce
+ * protection keys here anyway.
*/
static int break_ksm(struct vm_area_struct *vma, unsigned long addr)
{
@@ -367,12 +371,14 @@ static int break_ksm(struct vm_area_struct *vma, unsigned long addr)
do {
cond_resched();
- page = follow_page(vma, addr, FOLL_GET | FOLL_MIGRATION);
+ page = follow_page(vma, addr,
+ FOLL_GET | FOLL_MIGRATION | FOLL_REMOTE);
if (IS_ERR_OR_NULL(page))
break;
if (PageKsm(page))
ret = handle_mm_fault(vma->vm_mm, vma, addr,
- FAULT_FLAG_WRITE);
+ FAULT_FLAG_WRITE |
+ FAULT_FLAG_REMOTE);
else
ret = VM_FAULT_WRITE;
put_page(page);
diff --git a/mm/memory.c b/mm/memory.c
index d7e84fe6504d..76c44e5dffa2 100644
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -3379,7 +3379,8 @@ static int __handle_mm_fault(struct mm_struct *mm, struct vm_area_struct *vma,
pmd_t *pmd;
pte_t *pte;
- if (!arch_vma_access_permitted(vma, flags & FAULT_FLAG_WRITE))
+ if (!arch_vma_access_permitted(vma, flags & FAULT_FLAG_WRITE,
+ flags & FAULT_FLAG_REMOTE))
return VM_FAULT_SIGSEGV;
if (unlikely(is_vm_hugetlb_page(vma)))
generated by cgit v1.2.3 (git 2.25.1) at 2024-12-04 06:54:28 +0000