diff options
author | Linus Torvalds <torvalds@linux-foundation.org> | 2016-03-20 19:08:56 -0700 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2016-03-20 19:08:56 -0700 |
commit | 643ad15d47410d37d43daf3ef1c8ac52c281efa5 (patch) | |
tree | a864860cfe04c994c03d7946e12b3351e38a168b /mm | |
parent | 24b5e20f11a75866bbffc46c30a22fa50612a769 (diff) | |
parent | 0d47638f80a02b15869f1fe1fc09e5bf996750fd (diff) | |
download | linux-643ad15d47410d37d43daf3ef1c8ac52c281efa5.tar.bz2 |
Merge branch 'mm-pkeys-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 protection key support from Ingo Molnar:
"This tree adds support for a new memory protection hardware feature
that is available in upcoming Intel CPUs: 'protection keys' (pkeys).
There's a background article at LWN.net:
https://lwn.net/Articles/643797/
The gist is that protection keys allow the encoding of
user-controllable permission masks in the pte. So instead of having a
fixed protection mask in the pte (which needs a system call to change
and works on a per page basis), the user can map a (handful of)
protection mask variants and can change the masks runtime relatively
cheaply, without having to change every single page in the affected
virtual memory range.
This allows the dynamic switching of the protection bits of large
amounts of virtual memory, via user-space instructions. It also
allows more precise control of MMU permission bits: for example the
executable bit is separate from the read bit (see more about that
below).
This tree adds the MM infrastructure and low level x86 glue needed for
that, plus it adds a high level API to make use of protection keys -
if a user-space application calls:
mmap(..., PROT_EXEC);
or
mprotect(ptr, sz, PROT_EXEC);
(note PROT_EXEC-only, without PROT_READ/WRITE), the kernel will notice
this special case, and will set a special protection key on this
memory range. It also sets the appropriate bits in the Protection
Keys User Rights (PKRU) register so that the memory becomes unreadable
and unwritable.
So using protection keys the kernel is able to implement 'true'
PROT_EXEC on x86 CPUs: without protection keys PROT_EXEC implies
PROT_READ as well. Unreadable executable mappings have security
advantages: they cannot be read via information leaks to figure out
ASLR details, nor can they be scanned for ROP gadgets - and they
cannot be used by exploits for data purposes either.
We know about no user-space code that relies on pure PROT_EXEC
mappings today, but binary loaders could start making use of this new
feature to map binaries and libraries in a more secure fashion.
There is other pending pkeys work that offers more high level system
call APIs to manage protection keys - but those are not part of this
pull request.
Right now there's a Kconfig that controls this feature
(CONFIG_X86_INTEL_MEMORY_PROTECTION_KEYS) that is default enabled
(like most x86 CPU feature enablement code that has no runtime
overhead), but it's not user-configurable at the moment. If there's
any serious problem with this then we can make it configurable and/or
flip the default"
* 'mm-pkeys-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (38 commits)
x86/mm/pkeys: Fix mismerge of protection keys CPUID bits
mm/pkeys: Fix siginfo ABI breakage caused by new u64 field
x86/mm/pkeys: Fix access_error() denial of writes to write-only VMA
mm/core, x86/mm/pkeys: Add execute-only protection keys support
x86/mm/pkeys: Create an x86 arch_calc_vm_prot_bits() for VMA flags
x86/mm/pkeys: Allow kernel to modify user pkey rights register
x86/fpu: Allow setting of XSAVE state
x86/mm: Factor out LDT init from context init
mm/core, x86/mm/pkeys: Add arch_validate_pkey()
mm/core, arch, powerpc: Pass a protection key in to calc_vm_flag_bits()
x86/mm/pkeys: Actually enable Memory Protection Keys in the CPU
x86/mm/pkeys: Add Kconfig prompt to existing config option
x86/mm/pkeys: Dump pkey from VMA in /proc/pid/smaps
x86/mm/pkeys: Dump PKRU with other kernel registers
mm/core, x86/mm/pkeys: Differentiate instruction fetches
x86/mm/pkeys: Optimize fault handling in access_error()
mm/core: Do not enforce PKEY permissions on remote mm access
um, pkeys: Add UML arch_*_access_permitted() methods
mm/gup, x86/mm/pkeys: Check VMAs and PTEs for protection keys
x86/mm/gup: Simplify get_user_pages() PTE bit handling
...
Diffstat (limited to 'mm')
-rw-r--r-- | mm/Kconfig | 5 | ||||
-rw-r--r-- | mm/frame_vector.c | 2 | ||||
-rw-r--r-- | mm/gup.c | 127 | ||||
-rw-r--r-- | mm/ksm.c | 12 | ||||
-rw-r--r-- | mm/memory.c | 8 | ||||
-rw-r--r-- | mm/mempolicy.c | 6 | ||||
-rw-r--r-- | mm/mmap.c | 10 | ||||
-rw-r--r-- | mm/mprotect.c | 8 | ||||
-rw-r--r-- | mm/nommu.c | 66 | ||||
-rw-r--r-- | mm/process_vm_access.c | 11 | ||||
-rw-r--r-- | mm/util.c | 4 |
11 files changed, 200 insertions, 59 deletions
diff --git a/mm/Kconfig b/mm/Kconfig index 05efa6a5199e..989f8f3d77e0 100644 --- a/mm/Kconfig +++ b/mm/Kconfig @@ -667,3 +667,8 @@ config ZONE_DEVICE config FRAME_VECTOR bool + +config ARCH_USES_HIGH_VMA_FLAGS + bool +config ARCH_HAS_PKEYS + bool diff --git a/mm/frame_vector.c b/mm/frame_vector.c index 7cf2b7163222..381bb07ed14f 100644 --- a/mm/frame_vector.c +++ b/mm/frame_vector.c @@ -58,7 +58,7 @@ int get_vaddr_frames(unsigned long start, unsigned int nr_frames, if (!(vma->vm_flags & (VM_IO | VM_PFNMAP))) { vec->got_ref = true; vec->is_pfns = false; - ret = get_user_pages_locked(current, mm, start, nr_frames, + ret = get_user_pages_locked(start, nr_frames, write, force, (struct page **)(vec->ptrs), &locked); goto out; } @@ -1,3 +1,4 @@ +#define __DISABLE_GUP_DEPRECATED 1 #include <linux/kernel.h> #include <linux/errno.h> #include <linux/err.h> @@ -14,6 +15,7 @@ #include <linux/rwsem.h> #include <linux/hugetlb.h> +#include <asm/mmu_context.h> #include <asm/pgtable.h> #include <asm/tlbflush.h> @@ -363,6 +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) @@ -413,11 +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; @@ -443,6 +449,12 @@ static int check_vma_flags(struct vm_area_struct *vma, unsigned long gup_flags) if (!(vm_flags & VM_MAYREAD)) return -EFAULT; } + /* + * gups are always data accesses, not instruction + * fetches, so execute=false here + */ + if (!arch_vma_access_permitted(vma, write, false, foreign)) + return -EFAULT; return 0; } @@ -609,6 +621,28 @@ next_page: } 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 foreign = !!(fault_flags & FAULT_FLAG_REMOTE); + vm_flags_t vm_flags = write ? VM_WRITE : VM_READ; + + if (!(vm_flags & vma->vm_flags)) + return false; + + /* + * The architecture might have a hardware protection + * mechanism other than read/write that can deny access. + * + * gup always represents data access, not instruction + * fetches, so execute=false here: + */ + if (!arch_vma_access_permitted(vma, write, false, foreign)) + return false; + + return true; +} + /* * fixup_user_fault() - manually resolve a user page fault * @tsk: the task_struct to use for page fault accounting, or @@ -644,7 +678,6 @@ int fixup_user_fault(struct task_struct *tsk, struct mm_struct *mm, bool *unlocked) { struct vm_area_struct *vma; - vm_flags_t vm_flags; int ret, major = 0; if (unlocked) @@ -655,8 +688,7 @@ retry: if (!vma || address < vma->vm_start) return -EFAULT; - vm_flags = (fault_flags & FAULT_FLAG_WRITE) ? VM_WRITE : VM_READ; - if (!(vm_flags & vma->vm_flags)) + if (!vma_permits_fault(vma, fault_flags)) return -EFAULT; ret = handle_mm_fault(mm, vma, address, fault_flags); @@ -807,15 +839,15 @@ static __always_inline long __get_user_pages_locked(struct task_struct *tsk, * if (locked) * up_read(&mm->mmap_sem); */ -long get_user_pages_locked(struct task_struct *tsk, struct mm_struct *mm, - unsigned long start, unsigned long nr_pages, +long get_user_pages_locked6(unsigned long start, unsigned long nr_pages, int write, int force, struct page **pages, int *locked) { - return __get_user_pages_locked(tsk, mm, start, nr_pages, write, force, - pages, NULL, locked, true, FOLL_TOUCH); + return __get_user_pages_locked(current, current->mm, start, nr_pages, + write, force, pages, NULL, locked, true, + FOLL_TOUCH); } -EXPORT_SYMBOL(get_user_pages_locked); +EXPORT_SYMBOL(get_user_pages_locked6); /* * Same as get_user_pages_unlocked(...., FOLL_TOUCH) but it allows to @@ -860,17 +892,16 @@ EXPORT_SYMBOL(__get_user_pages_unlocked); * or if "force" shall be set to 1 (get_user_pages_fast misses the * "force" parameter). */ -long get_user_pages_unlocked(struct task_struct *tsk, struct mm_struct *mm, - unsigned long start, unsigned long nr_pages, +long get_user_pages_unlocked5(unsigned long start, unsigned long nr_pages, int write, int force, struct page **pages) { - return __get_user_pages_unlocked(tsk, mm, start, nr_pages, write, - force, pages, FOLL_TOUCH); + return __get_user_pages_unlocked(current, current->mm, start, nr_pages, + write, force, pages, FOLL_TOUCH); } -EXPORT_SYMBOL(get_user_pages_unlocked); +EXPORT_SYMBOL(get_user_pages_unlocked5); /* - * get_user_pages() - pin user pages in memory + * get_user_pages_remote() - pin user pages in memory * @tsk: the task_struct to use for page fault accounting, or * NULL if faults are not to be recorded. * @mm: mm_struct of target mm @@ -924,14 +955,32 @@ EXPORT_SYMBOL(get_user_pages_unlocked); * should use get_user_pages because it cannot pass * FAULT_FLAG_ALLOW_RETRY to handle_mm_fault. */ -long get_user_pages(struct task_struct *tsk, struct mm_struct *mm, - unsigned long start, unsigned long nr_pages, int write, - int force, struct page **pages, struct vm_area_struct **vmas) +long get_user_pages_remote(struct task_struct *tsk, struct mm_struct *mm, + unsigned long start, unsigned long nr_pages, + int write, int force, struct page **pages, + struct vm_area_struct **vmas) { return __get_user_pages_locked(tsk, mm, start, nr_pages, write, force, - pages, vmas, NULL, false, FOLL_TOUCH); + pages, vmas, NULL, false, + FOLL_TOUCH | FOLL_REMOTE); +} +EXPORT_SYMBOL(get_user_pages_remote); + +/* + * This is the same as get_user_pages_remote(), just with a + * less-flexible calling convention where we assume that the task + * and mm being operated on are the current task's. We also + * obviously don't pass FOLL_REMOTE in here. + */ +long get_user_pages6(unsigned long start, unsigned long nr_pages, + int write, int force, struct page **pages, + struct vm_area_struct **vmas) +{ + return __get_user_pages_locked(current, current->mm, start, nr_pages, + write, force, pages, vmas, NULL, false, + FOLL_TOUCH); } -EXPORT_SYMBOL(get_user_pages); +EXPORT_SYMBOL(get_user_pages6); /** * populate_vma_page_range() - populate a range of pages in the vma. @@ -1144,6 +1193,9 @@ static int gup_pte_range(pmd_t pmd, unsigned long addr, unsigned long end, pte_protnone(pte) || (write && !pte_write(pte))) goto pte_unmap; + if (!arch_pte_access_permitted(pte, write)) + goto pte_unmap; + VM_BUG_ON(!pfn_valid(pte_pfn(pte))); page = pte_page(pte); head = compound_head(page); @@ -1467,3 +1519,38 @@ int get_user_pages_fast(unsigned long start, int nr_pages, int write, } #endif /* CONFIG_HAVE_GENERIC_RCU_GUP */ + +long get_user_pages8(struct task_struct *tsk, struct mm_struct *mm, + unsigned long start, unsigned long nr_pages, + int write, int force, struct page **pages, + struct vm_area_struct **vmas) +{ + WARN_ONCE(tsk != current, "get_user_pages() called on remote task"); + WARN_ONCE(mm != current->mm, "get_user_pages() called on remote mm"); + + return get_user_pages6(start, nr_pages, write, force, pages, vmas); +} +EXPORT_SYMBOL(get_user_pages8); + +long get_user_pages_locked8(struct task_struct *tsk, struct mm_struct *mm, + unsigned long start, unsigned long nr_pages, + int write, int force, struct page **pages, int *locked) +{ + WARN_ONCE(tsk != current, "get_user_pages_locked() called on remote task"); + WARN_ONCE(mm != current->mm, "get_user_pages_locked() called on remote mm"); + + return get_user_pages_locked6(start, nr_pages, write, force, pages, locked); +} +EXPORT_SYMBOL(get_user_pages_locked8); + +long get_user_pages_unlocked7(struct task_struct *tsk, struct mm_struct *mm, + unsigned long start, unsigned long nr_pages, + int write, int force, struct page **pages) +{ + WARN_ONCE(tsk != current, "get_user_pages_unlocked() called on remote task"); + WARN_ONCE(mm != current->mm, "get_user_pages_unlocked() called on remote mm"); + + return get_user_pages_unlocked5(start, nr_pages, write, force, pages); +} +EXPORT_SYMBOL(get_user_pages_unlocked7); + @@ -352,13 +352,17 @@ static inline bool ksm_test_exit(struct mm_struct *mm) /* * We use break_ksm to break COW on a ksm page: it's a stripped down * - * if (get_user_pages(current, mm, addr, 1, 1, 1, &page, NULL) == 1) + * if (get_user_pages(addr, 1, 1, 1, &page, NULL) == 1) * put_page(page); * * but taking great care only to touch a ksm page, in a VM_MERGEABLE vma, * 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 ac6bc15c19be..81dca0083fcd 100644 --- a/mm/memory.c +++ b/mm/memory.c @@ -65,6 +65,7 @@ #include <linux/userfaultfd_k.h> #include <asm/io.h> +#include <asm/mmu_context.h> #include <asm/pgalloc.h> #include <asm/uaccess.h> #include <asm/tlb.h> @@ -3375,6 +3376,11 @@ 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, + flags & FAULT_FLAG_INSTRUCTION, + flags & FAULT_FLAG_REMOTE)) + return VM_FAULT_SIGSEGV; + if (unlikely(is_vm_hugetlb_page(vma))) return hugetlb_fault(mm, vma, address, flags); @@ -3691,7 +3697,7 @@ static int __access_remote_vm(struct task_struct *tsk, struct mm_struct *mm, void *maddr; struct page *page = NULL; - ret = get_user_pages(tsk, mm, addr, 1, + ret = get_user_pages_remote(tsk, mm, addr, 1, write, 1, &page, &vma); if (ret <= 0) { #ifndef CONFIG_HAVE_IOREMAP_PROT diff --git a/mm/mempolicy.c b/mm/mempolicy.c index b25de27b83d0..36cc01bc950a 100644 --- a/mm/mempolicy.c +++ b/mm/mempolicy.c @@ -846,12 +846,12 @@ static void get_policy_nodemask(struct mempolicy *p, nodemask_t *nodes) } } -static int lookup_node(struct mm_struct *mm, unsigned long addr) +static int lookup_node(unsigned long addr) { struct page *p; int err; - err = get_user_pages(current, mm, addr & PAGE_MASK, 1, 0, 0, &p, NULL); + err = get_user_pages(addr & PAGE_MASK, 1, 0, 0, &p, NULL); if (err >= 0) { err = page_to_nid(p); put_page(p); @@ -906,7 +906,7 @@ static long do_get_mempolicy(int *policy, nodemask_t *nmask, if (flags & MPOL_F_NODE) { if (flags & MPOL_F_ADDR) { - err = lookup_node(mm, addr); + err = lookup_node(addr); if (err < 0) goto out; *policy = err; diff --git a/mm/mmap.c b/mm/mmap.c index e06345aafa03..bd2e1a533bc1 100644 --- a/mm/mmap.c +++ b/mm/mmap.c @@ -42,6 +42,7 @@ #include <linux/printk.h> #include <linux/userfaultfd_k.h> #include <linux/moduleparam.h> +#include <linux/pkeys.h> #include <asm/uaccess.h> #include <asm/cacheflush.h> @@ -1145,6 +1146,7 @@ unsigned long do_mmap(struct file *file, unsigned long addr, unsigned long pgoff, unsigned long *populate) { struct mm_struct *mm = current->mm; + int pkey = 0; *populate = 0; @@ -1184,11 +1186,17 @@ unsigned long do_mmap(struct file *file, unsigned long addr, if (offset_in_page(addr)) return addr; + if (prot == PROT_EXEC) { + pkey = execute_only_pkey(mm); + if (pkey < 0) + pkey = 0; + } + /* Do simple checking here so the lower-level routines won't have * to. we assume access permissions have been handled by the open * of the memory object, so we don't do any here. */ - vm_flags |= calc_vm_prot_bits(prot) | calc_vm_flag_bits(flags) | + vm_flags |= calc_vm_prot_bits(prot, pkey) | calc_vm_flag_bits(flags) | mm->def_flags | VM_MAYREAD | VM_MAYWRITE | VM_MAYEXEC; if (flags & MAP_LOCKED) diff --git a/mm/mprotect.c b/mm/mprotect.c index f7cb3d4d9c2e..fa37c4cd973a 100644 --- a/mm/mprotect.c +++ b/mm/mprotect.c @@ -24,6 +24,7 @@ #include <linux/migrate.h> #include <linux/perf_event.h> #include <linux/ksm.h> +#include <linux/pkeys.h> #include <asm/uaccess.h> #include <asm/pgtable.h> #include <asm/cacheflush.h> @@ -354,7 +355,7 @@ fail: SYSCALL_DEFINE3(mprotect, unsigned long, start, size_t, len, unsigned long, prot) { - unsigned long vm_flags, nstart, end, tmp, reqprot; + unsigned long nstart, end, tmp, reqprot; struct vm_area_struct *vma, *prev; int error = -EINVAL; const int grows = prot & (PROT_GROWSDOWN|PROT_GROWSUP); @@ -380,8 +381,6 @@ SYSCALL_DEFINE3(mprotect, unsigned long, start, size_t, len, if ((prot & PROT_READ) && (current->personality & READ_IMPLIES_EXEC)) prot |= PROT_EXEC; - vm_flags = calc_vm_prot_bits(prot); - down_write(¤t->mm->mmap_sem); vma = find_vma(current->mm, start); @@ -411,10 +410,11 @@ SYSCALL_DEFINE3(mprotect, unsigned long, start, size_t, len, for (nstart = start ; ; ) { unsigned long newflags; + int pkey = arch_override_mprotect_pkey(vma, prot, -1); /* Here we know that vma->vm_start <= nstart < vma->vm_end. */ - newflags = vm_flags; + newflags = calc_vm_prot_bits(prot, pkey); newflags |= (vma->vm_flags & ~(VM_READ | VM_WRITE | VM_EXEC)); /* newflags >> 4 shift VM_MAY% in place of VM_% */ diff --git a/mm/nommu.c b/mm/nommu.c index 6402f2715d48..de8b6b6580c1 100644 --- a/mm/nommu.c +++ b/mm/nommu.c @@ -15,6 +15,8 @@ #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt +#define __DISABLE_GUP_DEPRECATED + #include <linux/export.h> #include <linux/mm.h> #include <linux/vmacache.h> @@ -159,8 +161,7 @@ finish_or_fault: * slab page or a secondary page from a compound page * - don't permit access to VMAs that don't support it, such as I/O mappings */ -long get_user_pages(struct task_struct *tsk, struct mm_struct *mm, - unsigned long start, unsigned long nr_pages, +long get_user_pages6(unsigned long start, unsigned long nr_pages, int write, int force, struct page **pages, struct vm_area_struct **vmas) { @@ -171,20 +172,18 @@ long get_user_pages(struct task_struct *tsk, struct mm_struct *mm, if (force) flags |= FOLL_FORCE; - return __get_user_pages(tsk, mm, start, nr_pages, flags, pages, vmas, - NULL); + return __get_user_pages(current, current->mm, start, nr_pages, flags, + pages, vmas, NULL); } -EXPORT_SYMBOL(get_user_pages); +EXPORT_SYMBOL(get_user_pages6); -long get_user_pages_locked(struct task_struct *tsk, struct mm_struct *mm, - unsigned long start, unsigned long nr_pages, - int write, int force, struct page **pages, - int *locked) +long get_user_pages_locked6(unsigned long start, unsigned long nr_pages, + int write, int force, struct page **pages, + int *locked) { - return get_user_pages(tsk, mm, start, nr_pages, write, force, - pages, NULL); + return get_user_pages6(start, nr_pages, write, force, pages, NULL); } -EXPORT_SYMBOL(get_user_pages_locked); +EXPORT_SYMBOL(get_user_pages_locked6); long __get_user_pages_unlocked(struct task_struct *tsk, struct mm_struct *mm, unsigned long start, unsigned long nr_pages, @@ -193,21 +192,20 @@ long __get_user_pages_unlocked(struct task_struct *tsk, struct mm_struct *mm, { long ret; down_read(&mm->mmap_sem); - ret = get_user_pages(tsk, mm, start, nr_pages, write, force, - pages, NULL); + ret = __get_user_pages(tsk, mm, start, nr_pages, gup_flags, pages, + NULL, NULL); up_read(&mm->mmap_sem); return ret; } EXPORT_SYMBOL(__get_user_pages_unlocked); -long get_user_pages_unlocked(struct task_struct *tsk, struct mm_struct *mm, - unsigned long start, unsigned long nr_pages, +long get_user_pages_unlocked5(unsigned long start, unsigned long nr_pages, int write, int force, struct page **pages) { - return __get_user_pages_unlocked(tsk, mm, start, nr_pages, write, - force, pages, 0); + return __get_user_pages_unlocked(current, current->mm, start, nr_pages, + write, force, pages, 0); } -EXPORT_SYMBOL(get_user_pages_unlocked); +EXPORT_SYMBOL(get_user_pages_unlocked5); /** * follow_pfn - look up PFN at a user virtual address @@ -1061,7 +1059,7 @@ static unsigned long determine_vm_flags(struct file *file, { unsigned long vm_flags; - vm_flags = calc_vm_prot_bits(prot) | calc_vm_flag_bits(flags); + vm_flags = calc_vm_prot_bits(prot, 0) | calc_vm_flag_bits(flags); /* vm_flags |= mm->def_flags; */ if (!(capabilities & NOMMU_MAP_DIRECT)) { @@ -1991,3 +1989,31 @@ static int __meminit init_admin_reserve(void) return 0; } subsys_initcall(init_admin_reserve); + +long get_user_pages8(struct task_struct *tsk, struct mm_struct *mm, + unsigned long start, unsigned long nr_pages, + int write, int force, struct page **pages, + struct vm_area_struct **vmas) +{ + return get_user_pages6(start, nr_pages, write, force, pages, vmas); +} +EXPORT_SYMBOL(get_user_pages8); + +long get_user_pages_locked8(struct task_struct *tsk, struct mm_struct *mm, + unsigned long start, unsigned long nr_pages, + int write, int force, struct page **pages, + int *locked) +{ + return get_user_pages_locked6(start, nr_pages, write, + force, pages, locked); +} +EXPORT_SYMBOL(get_user_pages_locked8); + +long get_user_pages_unlocked7(struct task_struct *tsk, struct mm_struct *mm, + unsigned long start, unsigned long nr_pages, + int write, int force, struct page **pages) +{ + return get_user_pages_unlocked5(start, nr_pages, write, force, pages); +} +EXPORT_SYMBOL(get_user_pages_unlocked7); + diff --git a/mm/process_vm_access.c b/mm/process_vm_access.c index 5d453e58ddbf..07514d41ebcc 100644 --- a/mm/process_vm_access.c +++ b/mm/process_vm_access.c @@ -98,9 +98,14 @@ static int process_vm_rw_single_vec(unsigned long addr, int pages = min(nr_pages, max_pages_per_loop); size_t bytes; - /* Get the pages we're interested in */ - pages = get_user_pages_unlocked(task, mm, pa, pages, - vm_write, 0, process_pages); + /* + * Get the pages we're interested in. We must + * add FOLL_REMOTE because task/mm might not + * current/current->mm + */ + pages = __get_user_pages_unlocked(task, mm, pa, pages, + vm_write, 0, process_pages, + FOLL_REMOTE); if (pages <= 0) return -EFAULT; diff --git a/mm/util.c b/mm/util.c index 47a57e557614..6cc81e7b8705 100644 --- a/mm/util.c +++ b/mm/util.c @@ -283,9 +283,7 @@ EXPORT_SYMBOL_GPL(__get_user_pages_fast); int __weak get_user_pages_fast(unsigned long start, int nr_pages, int write, struct page **pages) { - struct mm_struct *mm = current->mm; - return get_user_pages_unlocked(current, mm, start, nr_pages, - write, 0, pages); + return get_user_pages_unlocked(start, nr_pages, write, 0, pages); } EXPORT_SYMBOL_GPL(get_user_pages_fast); |