diff options
Diffstat (limited to 'mm')
| -rw-r--r-- | mm/Makefile | 3 | ||||
| -rw-r--r-- | mm/frame_vector.c | 9 | ||||
| -rw-r--r-- | mm/gup.c | 64 | ||||
| -rw-r--r-- | mm/kasan/kasan.c | 22 | ||||
| -rw-r--r-- | mm/memory.c | 16 | ||||
| -rw-r--r-- | mm/mempolicy.c | 2 | ||||
| -rw-r--r-- | mm/nommu.c | 38 | ||||
| -rw-r--r-- | mm/page_alloc.c | 5 | ||||
| -rw-r--r-- | mm/percpu.c | 38 | ||||
| -rw-r--r-- | mm/process_vm_access.c | 7 | ||||
| -rw-r--r-- | mm/util.c | 8 |
11 files changed, 117 insertions, 95 deletions
diff --git a/mm/Makefile b/mm/Makefile index 2ca1faf3fa09..295bd7a9f76b 100644 --- a/mm/Makefile +++ b/mm/Makefile @@ -21,9 +21,6 @@ KCOV_INSTRUMENT_memcontrol.o := n KCOV_INSTRUMENT_mmzone.o := n KCOV_INSTRUMENT_vmstat.o := n -# Since __builtin_frame_address does work as used, disable the warning. -CFLAGS_usercopy.o += $(call cc-disable-warning, frame-address) - mmu-y := nommu.o mmu-$(CONFIG_MMU) := gup.o highmem.o memory.o mincore.o \ mlock.o mmap.o mprotect.o mremap.o msync.o rmap.o \ diff --git a/mm/frame_vector.c b/mm/frame_vector.c index 381bb07ed14f..db77dcb38afd 100644 --- a/mm/frame_vector.c +++ b/mm/frame_vector.c @@ -11,10 +11,7 @@ * get_vaddr_frames() - map virtual addresses to pfns * @start: starting user address * @nr_frames: number of pages / pfns from start to map - * @write: whether pages will be written to by the caller - * @force: whether to force write access even if user mapping is - * readonly. See description of the same argument of - get_user_pages(). + * @gup_flags: flags modifying lookup behaviour * @vec: structure which receives pages / pfns of the addresses mapped. * It should have space for at least nr_frames entries. * @@ -34,7 +31,7 @@ * This function takes care of grabbing mmap_sem as necessary. */ int get_vaddr_frames(unsigned long start, unsigned int nr_frames, - bool write, bool force, struct frame_vector *vec) + unsigned int gup_flags, struct frame_vector *vec) { struct mm_struct *mm = current->mm; struct vm_area_struct *vma; @@ -59,7 +56,7 @@ int get_vaddr_frames(unsigned long start, unsigned int nr_frames, vec->got_ref = true; vec->is_pfns = false; ret = get_user_pages_locked(start, nr_frames, - write, force, (struct page **)(vec->ptrs), &locked); + gup_flags, (struct page **)(vec->ptrs), &locked); goto out; } @@ -60,6 +60,16 @@ static int follow_pfn_pte(struct vm_area_struct *vma, unsigned long address, return -EEXIST; } +/* + * FOLL_FORCE can write to even unwritable pte's, but only + * after we've gone through a COW cycle and they are dirty. + */ +static inline bool can_follow_write_pte(pte_t pte, unsigned int flags) +{ + return pte_write(pte) || + ((flags & FOLL_FORCE) && (flags & FOLL_COW) && pte_dirty(pte)); +} + static struct page *follow_page_pte(struct vm_area_struct *vma, unsigned long address, pmd_t *pmd, unsigned int flags) { @@ -95,7 +105,7 @@ retry: } if ((flags & FOLL_NUMA) && pte_protnone(pte)) goto no_page; - if ((flags & FOLL_WRITE) && !pte_write(pte)) { + if ((flags & FOLL_WRITE) && !can_follow_write_pte(pte, flags)) { pte_unmap_unlock(ptep, ptl); return NULL; } @@ -412,7 +422,7 @@ static int faultin_page(struct task_struct *tsk, struct vm_area_struct *vma, * reCOWed by userspace write). */ if ((ret & VM_FAULT_WRITE) && !(vma->vm_flags & VM_WRITE)) - *flags &= ~FOLL_WRITE; + *flags |= FOLL_COW; return 0; } @@ -729,7 +739,6 @@ static __always_inline 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, struct vm_area_struct **vmas, int *locked, bool notify_drop, @@ -747,10 +756,6 @@ static __always_inline long __get_user_pages_locked(struct task_struct *tsk, if (pages) flags |= FOLL_GET; - if (write) - flags |= FOLL_WRITE; - if (force) - flags |= FOLL_FORCE; pages_done = 0; lock_dropped = false; @@ -843,12 +848,12 @@ static __always_inline long __get_user_pages_locked(struct task_struct *tsk, * up_read(&mm->mmap_sem); */ long get_user_pages_locked(unsigned long start, unsigned long nr_pages, - int write, int force, struct page **pages, + unsigned int gup_flags, struct page **pages, int *locked) { return __get_user_pages_locked(current, current->mm, start, nr_pages, - write, force, pages, NULL, locked, true, - FOLL_TOUCH); + pages, NULL, locked, true, + gup_flags | FOLL_TOUCH); } EXPORT_SYMBOL(get_user_pages_locked); @@ -864,14 +869,14 @@ EXPORT_SYMBOL(get_user_pages_locked); */ __always_inline long __get_user_pages_unlocked(struct task_struct *tsk, struct mm_struct *mm, unsigned long start, unsigned long nr_pages, - int write, int force, struct page **pages, - unsigned int gup_flags) + struct page **pages, unsigned int gup_flags) { long ret; int locked = 1; + down_read(&mm->mmap_sem); - ret = __get_user_pages_locked(tsk, mm, start, nr_pages, write, force, - pages, NULL, &locked, false, gup_flags); + ret = __get_user_pages_locked(tsk, mm, start, nr_pages, pages, NULL, + &locked, false, gup_flags); if (locked) up_read(&mm->mmap_sem); return ret; @@ -896,10 +901,10 @@ EXPORT_SYMBOL(__get_user_pages_unlocked); * "force" parameter). */ long get_user_pages_unlocked(unsigned long start, unsigned long nr_pages, - int write, int force, struct page **pages) + struct page **pages, unsigned int gup_flags) { return __get_user_pages_unlocked(current, current->mm, start, nr_pages, - write, force, pages, FOLL_TOUCH); + pages, gup_flags | FOLL_TOUCH); } EXPORT_SYMBOL(get_user_pages_unlocked); @@ -910,9 +915,7 @@ EXPORT_SYMBOL(get_user_pages_unlocked); * @mm: mm_struct of target mm * @start: starting user address * @nr_pages: number of pages from start to pin - * @write: whether pages will be written to by the caller - * @force: whether to force access even when user mapping is currently - * protected (but never forces write access to shared mapping). + * @gup_flags: flags modifying lookup behaviour * @pages: array that receives pointers to the pages pinned. * Should be at least nr_pages long. Or NULL, if caller * only intends to ensure the pages are faulted in. @@ -941,9 +944,9 @@ EXPORT_SYMBOL(get_user_pages_unlocked); * or similar operation cannot guarantee anything stronger anyway because * locks can't be held over the syscall boundary. * - * If write=0, the page must not be written to. If the page is written to, - * set_page_dirty (or set_page_dirty_lock, as appropriate) must be called - * after the page is finished with, and before put_page is called. + * If gup_flags & FOLL_WRITE == 0, the page must not be written to. If the page + * is written to, set_page_dirty (or set_page_dirty_lock, as appropriate) must + * be called after the page is finished with, and before put_page is called. * * get_user_pages is typically used for fewer-copy IO operations, to get a * handle on the memory by some means other than accesses via the user virtual @@ -960,12 +963,12 @@ EXPORT_SYMBOL(get_user_pages_unlocked); */ 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, + unsigned int gup_flags, 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 | FOLL_REMOTE); + return __get_user_pages_locked(tsk, mm, start, nr_pages, pages, vmas, + NULL, false, + gup_flags | FOLL_TOUCH | FOLL_REMOTE); } EXPORT_SYMBOL(get_user_pages_remote); @@ -976,12 +979,12 @@ EXPORT_SYMBOL(get_user_pages_remote); * obviously don't pass FOLL_REMOTE in here. */ long get_user_pages(unsigned long start, unsigned long nr_pages, - int write, int force, struct page **pages, + unsigned int gup_flags, 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); + pages, vmas, NULL, false, + gup_flags | FOLL_TOUCH); } EXPORT_SYMBOL(get_user_pages); @@ -1505,7 +1508,8 @@ int get_user_pages_fast(unsigned long start, int nr_pages, int write, start += nr << PAGE_SHIFT; pages += nr; - ret = get_user_pages_unlocked(start, nr_pages - nr, write, 0, pages); + ret = get_user_pages_unlocked(start, nr_pages - nr, pages, + write ? FOLL_WRITE : 0); /* Have to be a bit careful with return values */ if (nr > 0) { diff --git a/mm/kasan/kasan.c b/mm/kasan/kasan.c index 88af13c00d3c..70c009741aab 100644 --- a/mm/kasan/kasan.c +++ b/mm/kasan/kasan.c @@ -34,6 +34,7 @@ #include <linux/string.h> #include <linux/types.h> #include <linux/vmalloc.h> +#include <linux/bug.h> #include "kasan.h" #include "../slab.h" @@ -62,7 +63,7 @@ void kasan_unpoison_shadow(const void *address, size_t size) } } -static void __kasan_unpoison_stack(struct task_struct *task, void *sp) +static void __kasan_unpoison_stack(struct task_struct *task, const void *sp) { void *base = task_stack_page(task); size_t size = sp - base; @@ -77,9 +78,24 @@ void kasan_unpoison_task_stack(struct task_struct *task) } /* Unpoison the stack for the current task beyond a watermark sp value. */ -asmlinkage void kasan_unpoison_remaining_stack(void *sp) +asmlinkage void kasan_unpoison_task_stack_below(const void *watermark) { - __kasan_unpoison_stack(current, sp); + __kasan_unpoison_stack(current, watermark); +} + +/* + * Clear all poison for the region between the current SP and a provided + * watermark value, as is sometimes required prior to hand-crafted asm function + * returns in the middle of functions. + */ +void kasan_unpoison_stack_above_sp_to(const void *watermark) +{ + const void *sp = __builtin_frame_address(0); + size_t size = watermark - sp; + + if (WARN_ON(sp > watermark)) + return; + kasan_unpoison_shadow(sp, size); } /* diff --git a/mm/memory.c b/mm/memory.c index fc1987dfd8cc..e18c57bdc75c 100644 --- a/mm/memory.c +++ b/mm/memory.c @@ -3869,10 +3869,11 @@ EXPORT_SYMBOL_GPL(generic_access_phys); * given task for page fault accounting. */ static int __access_remote_vm(struct task_struct *tsk, struct mm_struct *mm, - unsigned long addr, void *buf, int len, int write) + unsigned long addr, void *buf, int len, unsigned int gup_flags) { struct vm_area_struct *vma; void *old_buf = buf; + int write = gup_flags & FOLL_WRITE; down_read(&mm->mmap_sem); /* ignore errors, just check how much was successfully transferred */ @@ -3882,7 +3883,7 @@ static int __access_remote_vm(struct task_struct *tsk, struct mm_struct *mm, struct page *page = NULL; ret = get_user_pages_remote(tsk, mm, addr, 1, - write, 1, &page, &vma); + gup_flags, &page, &vma); if (ret <= 0) { #ifndef CONFIG_HAVE_IOREMAP_PROT break; @@ -3934,14 +3935,14 @@ static int __access_remote_vm(struct task_struct *tsk, struct mm_struct *mm, * @addr: start address to access * @buf: source or destination buffer * @len: number of bytes to transfer - * @write: whether the access is a write + * @gup_flags: flags modifying lookup behaviour * * The caller must hold a reference on @mm. */ int access_remote_vm(struct mm_struct *mm, unsigned long addr, - void *buf, int len, int write) + void *buf, int len, unsigned int gup_flags) { - return __access_remote_vm(NULL, mm, addr, buf, len, write); + return __access_remote_vm(NULL, mm, addr, buf, len, gup_flags); } /* @@ -3950,7 +3951,7 @@ int access_remote_vm(struct mm_struct *mm, unsigned long addr, * Do not walk the page table directly, use get_user_pages */ int access_process_vm(struct task_struct *tsk, unsigned long addr, - void *buf, int len, int write) + void *buf, int len, unsigned int gup_flags) { struct mm_struct *mm; int ret; @@ -3959,7 +3960,8 @@ int access_process_vm(struct task_struct *tsk, unsigned long addr, if (!mm) return 0; - ret = __access_remote_vm(tsk, mm, addr, buf, len, write); + ret = __access_remote_vm(tsk, mm, addr, buf, len, gup_flags); + mmput(mm); return ret; diff --git a/mm/mempolicy.c b/mm/mempolicy.c index ad1c96ac313c..0b859af06b87 100644 --- a/mm/mempolicy.c +++ b/mm/mempolicy.c @@ -850,7 +850,7 @@ static int lookup_node(unsigned long addr) struct page *p; int err; - err = get_user_pages(addr & PAGE_MASK, 1, 0, 0, &p, NULL); + err = get_user_pages(addr & PAGE_MASK, 1, 0, &p, NULL); if (err >= 0) { err = page_to_nid(p); put_page(p); diff --git a/mm/nommu.c b/mm/nommu.c index 95daf81a4855..db5fd1795298 100644 --- a/mm/nommu.c +++ b/mm/nommu.c @@ -160,33 +160,25 @@ finish_or_fault: * - don't permit access to VMAs that don't support it, such as I/O mappings */ long get_user_pages(unsigned long start, unsigned long nr_pages, - int write, int force, struct page **pages, + unsigned int gup_flags, struct page **pages, struct vm_area_struct **vmas) { - int flags = 0; - - if (write) - flags |= FOLL_WRITE; - if (force) - flags |= FOLL_FORCE; - - return __get_user_pages(current, current->mm, start, nr_pages, flags, - pages, vmas, NULL); + return __get_user_pages(current, current->mm, start, nr_pages, + gup_flags, pages, vmas, NULL); } EXPORT_SYMBOL(get_user_pages); long get_user_pages_locked(unsigned long start, unsigned long nr_pages, - int write, int force, struct page **pages, + unsigned int gup_flags, struct page **pages, int *locked) { - return get_user_pages(start, nr_pages, write, force, pages, NULL); + return get_user_pages(start, nr_pages, gup_flags, pages, NULL); } EXPORT_SYMBOL(get_user_pages_locked); long __get_user_pages_unlocked(struct task_struct *tsk, struct mm_struct *mm, unsigned long start, unsigned long nr_pages, - int write, int force, struct page **pages, - unsigned int gup_flags) + struct page **pages, unsigned int gup_flags) { long ret; down_read(&mm->mmap_sem); @@ -198,10 +190,10 @@ long __get_user_pages_unlocked(struct task_struct *tsk, struct mm_struct *mm, EXPORT_SYMBOL(__get_user_pages_unlocked); long get_user_pages_unlocked(unsigned long start, unsigned long nr_pages, - int write, int force, struct page **pages) + struct page **pages, unsigned int gup_flags) { return __get_user_pages_unlocked(current, current->mm, start, nr_pages, - write, force, pages, 0); + pages, gup_flags); } EXPORT_SYMBOL(get_user_pages_unlocked); @@ -1817,9 +1809,10 @@ void filemap_map_pages(struct fault_env *fe, EXPORT_SYMBOL(filemap_map_pages); static int __access_remote_vm(struct task_struct *tsk, struct mm_struct *mm, - unsigned long addr, void *buf, int len, int write) + unsigned long addr, void *buf, int len, unsigned int gup_flags) { struct vm_area_struct *vma; + int write = gup_flags & FOLL_WRITE; down_read(&mm->mmap_sem); @@ -1854,21 +1847,22 @@ static int __access_remote_vm(struct task_struct *tsk, struct mm_struct *mm, * @addr: start address to access * @buf: source or destination buffer * @len: number of bytes to transfer - * @write: whether the access is a write + * @gup_flags: flags modifying lookup behaviour * * The caller must hold a reference on @mm. */ int access_remote_vm(struct mm_struct *mm, unsigned long addr, - void *buf, int len, int write) + void *buf, int len, unsigned int gup_flags) { - return __access_remote_vm(NULL, mm, addr, buf, len, write); + return __access_remote_vm(NULL, mm, addr, buf, len, gup_flags); } /* * Access another process' address space. * - source/target buffer must be kernel space */ -int access_process_vm(struct task_struct *tsk, unsigned long addr, void *buf, int len, int write) +int access_process_vm(struct task_struct *tsk, unsigned long addr, void *buf, int len, + unsigned int gup_flags) { struct mm_struct *mm; @@ -1879,7 +1873,7 @@ int access_process_vm(struct task_struct *tsk, unsigned long addr, void *buf, in if (!mm) return 0; - len = __access_remote_vm(tsk, mm, addr, buf, len, write); + len = __access_remote_vm(tsk, mm, addr, buf, len, gup_flags); mmput(mm); return len; diff --git a/mm/page_alloc.c b/mm/page_alloc.c index ca423cc20b59..2b3bf6767d54 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -91,6 +91,11 @@ EXPORT_PER_CPU_SYMBOL(_numa_mem_); int _node_numa_mem_[MAX_NUMNODES]; #endif +#ifdef CONFIG_GCC_PLUGIN_LATENT_ENTROPY +volatile u64 latent_entropy __latent_entropy; +EXPORT_SYMBOL(latent_entropy); +#endif + /* * Array of node states. */ diff --git a/mm/percpu.c b/mm/percpu.c index 9903830aaebb..255714302394 100644 --- a/mm/percpu.c +++ b/mm/percpu.c @@ -1961,8 +1961,9 @@ int __init pcpu_embed_first_chunk(size_t reserved_size, size_t dyn_size, void *base = (void *)ULONG_MAX; void **areas = NULL; struct pcpu_alloc_info *ai; - size_t size_sum, areas_size, max_distance; - int group, i, rc; + size_t size_sum, areas_size; + unsigned long max_distance; + int group, i, highest_group, rc; ai = pcpu_build_alloc_info(reserved_size, dyn_size, atom_size, cpu_distance_fn); @@ -1978,7 +1979,8 @@ int __init pcpu_embed_first_chunk(size_t reserved_size, size_t dyn_size, goto out_free; } - /* allocate, copy and determine base address */ + /* allocate, copy and determine base address & max_distance */ + highest_group = 0; for (group = 0; group < ai->nr_groups; group++) { struct pcpu_group_info *gi = &ai->groups[group]; unsigned int cpu = NR_CPUS; @@ -1999,6 +2001,21 @@ int __init pcpu_embed_first_chunk(size_t reserved_size, size_t dyn_size, areas[group] = ptr; base = min(ptr, base); + if (ptr > areas[highest_group]) + highest_group = group; + } + max_distance = areas[highest_group] - base; + max_distance += ai->unit_size * ai->groups[highest_group].nr_units; + + /* warn if maximum distance is further than 75% of vmalloc space */ + if (max_distance > VMALLOC_TOTAL * 3 / 4) { + pr_warn("max_distance=0x%lx too large for vmalloc space 0x%lx\n", + max_distance, VMALLOC_TOTAL); +#ifdef CONFIG_NEED_PER_CPU_PAGE_FIRST_CHUNK + /* and fail if we have fallback */ + rc = -EINVAL; + goto out_free_areas; +#endif } /* @@ -2023,23 +2040,8 @@ int __init pcpu_embed_first_chunk(size_t reserved_size, size_t dyn_size, } /* base address is now known, determine group base offsets */ - max_distance = 0; for (group = 0; group < ai->nr_groups; group++) { ai->groups[group].base_offset = areas[group] - base; - max_distance = max_t(size_t, max_distance, - ai->groups[group].base_offset); - } - max_distance += ai->unit_size; - - /* warn if maximum distance is further than 75% of vmalloc space */ - if (max_distance > VMALLOC_TOTAL * 3 / 4) { - pr_warn("max_distance=0x%zx too large for vmalloc space 0x%lx\n", - max_distance, VMALLOC_TOTAL); -#ifdef CONFIG_NEED_PER_CPU_PAGE_FIRST_CHUNK - /* and fail if we have fallback */ - rc = -EINVAL; - goto out_free; -#endif } pr_info("Embedded %zu pages/cpu @%p s%zu r%zu d%zu u%zu\n", diff --git a/mm/process_vm_access.c b/mm/process_vm_access.c index 07514d41ebcc..be8dc8d1edb9 100644 --- a/mm/process_vm_access.c +++ b/mm/process_vm_access.c @@ -88,12 +88,16 @@ static int process_vm_rw_single_vec(unsigned long addr, ssize_t rc = 0; unsigned long max_pages_per_loop = PVM_MAX_KMALLOC_PAGES / sizeof(struct pages *); + unsigned int flags = FOLL_REMOTE; /* Work out address and page range required */ if (len == 0) return 0; nr_pages = (addr + len - 1) / PAGE_SIZE - addr / PAGE_SIZE + 1; + if (vm_write) + flags |= FOLL_WRITE; + while (!rc && nr_pages && iov_iter_count(iter)) { int pages = min(nr_pages, max_pages_per_loop); size_t bytes; @@ -104,8 +108,7 @@ static int process_vm_rw_single_vec(unsigned long addr, * current/current->mm */ pages = __get_user_pages_unlocked(task, mm, pa, pages, - vm_write, 0, process_pages, - FOLL_REMOTE); + process_pages, flags); if (pages <= 0) return -EFAULT; diff --git a/mm/util.c b/mm/util.c index 662cddf914af..952cbe7ad7b7 100644 --- a/mm/util.c +++ b/mm/util.c @@ -283,7 +283,8 @@ EXPORT_SYMBOL_GPL(__get_user_pages_fast); int __weak get_user_pages_fast(unsigned long start, int nr_pages, int write, struct page **pages) { - return get_user_pages_unlocked(start, nr_pages, write, 0, pages); + return get_user_pages_unlocked(start, nr_pages, pages, + write ? FOLL_WRITE : 0); } EXPORT_SYMBOL_GPL(get_user_pages_fast); @@ -623,7 +624,7 @@ int get_cmdline(struct task_struct *task, char *buffer, int buflen) if (len > buflen) len = buflen; - res = access_process_vm(task, arg_start, buffer, len, 0); + res = access_process_vm(task, arg_start, buffer, len, FOLL_FORCE); /* * If the nul at the end of args has been overwritten, then @@ -638,7 +639,8 @@ int get_cmdline(struct task_struct *task, char *buffer, int buflen) if (len > buflen - res) len = buflen - res; res += access_process_vm(task, env_start, - buffer+res, len, 0); + buffer+res, len, + FOLL_FORCE); res = strnlen(buffer, res); } } |