diff options
Diffstat (limited to 'tools/testing/vma')
| -rw-r--r-- | tools/testing/vma/.gitignore | 7 | ||||
| -rw-r--r-- | tools/testing/vma/Makefile | 18 | ||||
| -rw-r--r-- | tools/testing/vma/linux/atomic.h | 17 | ||||
| -rw-r--r-- | tools/testing/vma/linux/mmzone.h | 38 | ||||
| -rw-r--r-- | tools/testing/vma/vma.c | 1715 | ||||
| -rw-r--r-- | tools/testing/vma/vma_internal.h | 1487 |
6 files changed, 3282 insertions, 0 deletions
diff --git a/tools/testing/vma/.gitignore b/tools/testing/vma/.gitignore new file mode 100644 index 000000000000..b003258eba79 --- /dev/null +++ b/tools/testing/vma/.gitignore @@ -0,0 +1,7 @@ +# SPDX-License-Identifier: GPL-2.0-only +generated/bit-length.h +generated/map-shift.h +generated/autoconf.h +idr.c +radix-tree.c +vma diff --git a/tools/testing/vma/Makefile b/tools/testing/vma/Makefile new file mode 100644 index 000000000000..66f3831a668f --- /dev/null +++ b/tools/testing/vma/Makefile @@ -0,0 +1,18 @@ +# SPDX-License-Identifier: GPL-2.0-or-later + +.PHONY: default clean + +default: vma + +include ../shared/shared.mk + +OFILES = $(SHARED_OFILES) vma.o maple-shim.o +TARGETS = vma + +vma.o: vma.c vma_internal.h ../../../mm/vma.c ../../../mm/vma_init.c ../../../mm/vma_exec.c ../../../mm/vma.h + +vma: $(OFILES) + $(CC) $(CFLAGS) -o $@ $(OFILES) $(LDLIBS) + +clean: + $(RM) $(TARGETS) *.o radix-tree.c idr.c generated/map-shift.h generated/bit-length.h generated/autoconf.h diff --git a/tools/testing/vma/linux/atomic.h b/tools/testing/vma/linux/atomic.h new file mode 100644 index 000000000000..788c597c4fde --- /dev/null +++ b/tools/testing/vma/linux/atomic.h @@ -0,0 +1,17 @@ +/* SPDX-License-Identifier: GPL-2.0-or-later */ + +#ifndef _LINUX_ATOMIC_H +#define _LINUX_ATOMIC_H + +#define atomic_t int32_t +#define atomic_inc(x) uatomic_inc(x) +#define atomic_read(x) uatomic_read(x) +#define atomic_set(x, y) uatomic_set(x, y) +#define U8_MAX UCHAR_MAX + +#ifndef atomic_cmpxchg_relaxed +#define atomic_cmpxchg_relaxed uatomic_cmpxchg +#define atomic_cmpxchg_release uatomic_cmpxchg +#endif /* atomic_cmpxchg_relaxed */ + +#endif /* _LINUX_ATOMIC_H */ diff --git a/tools/testing/vma/linux/mmzone.h b/tools/testing/vma/linux/mmzone.h new file mode 100644 index 000000000000..33cd1517f7a3 --- /dev/null +++ b/tools/testing/vma/linux/mmzone.h @@ -0,0 +1,38 @@ +/* SPDX-License-Identifier: GPL-2.0-or-later */ + +#ifndef _LINUX_MMZONE_H +#define _LINUX_MMZONE_H + +#include <linux/atomic.h> + +struct pglist_data *first_online_pgdat(void); +struct pglist_data *next_online_pgdat(struct pglist_data *pgdat); + +#define for_each_online_pgdat(pgdat) \ + for (pgdat = first_online_pgdat(); \ + pgdat; \ + pgdat = next_online_pgdat(pgdat)) + +enum zone_type { + __MAX_NR_ZONES +}; + +#define MAX_NR_ZONES __MAX_NR_ZONES +#define MAX_PAGE_ORDER 10 +#define MAX_ORDER_NR_PAGES (1 << MAX_PAGE_ORDER) + +#define pageblock_order MAX_PAGE_ORDER +#define pageblock_nr_pages BIT(pageblock_order) +#define pageblock_align(pfn) ALIGN((pfn), pageblock_nr_pages) +#define pageblock_start_pfn(pfn) ALIGN_DOWN((pfn), pageblock_nr_pages) + +struct zone { + atomic_long_t managed_pages; +}; + +typedef struct pglist_data { + struct zone node_zones[MAX_NR_ZONES]; + +} pg_data_t; + +#endif /* _LINUX_MMZONE_H */ diff --git a/tools/testing/vma/vma.c b/tools/testing/vma/vma.c new file mode 100644 index 000000000000..2be7597a2ac2 --- /dev/null +++ b/tools/testing/vma/vma.c @@ -0,0 +1,1715 @@ +// SPDX-License-Identifier: GPL-2.0-or-later + +#include <stdbool.h> +#include <stdio.h> +#include <stdlib.h> + +#include "generated/bit-length.h" + +#include "maple-shared.h" +#include "vma_internal.h" + +/* Include so header guard set. */ +#include "../../../mm/vma.h" + +static bool fail_prealloc; + +/* Then override vma_iter_prealloc() so we can choose to fail it. */ +#define vma_iter_prealloc(vmi, vma) \ + (fail_prealloc ? -ENOMEM : mas_preallocate(&(vmi)->mas, (vma), GFP_KERNEL)) + +#define CONFIG_DEFAULT_MMAP_MIN_ADDR 65536 + +unsigned long mmap_min_addr = CONFIG_DEFAULT_MMAP_MIN_ADDR; +unsigned long dac_mmap_min_addr = CONFIG_DEFAULT_MMAP_MIN_ADDR; +unsigned long stack_guard_gap = 256UL<<PAGE_SHIFT; + +/* + * Directly import the VMA implementation here. Our vma_internal.h wrapper + * provides userland-equivalent functionality for everything vma.c uses. + */ +#include "../../../mm/vma_init.c" +#include "../../../mm/vma_exec.c" +#include "../../../mm/vma.c" + +const struct vm_operations_struct vma_dummy_vm_ops; +static struct anon_vma dummy_anon_vma; + +#define ASSERT_TRUE(_expr) \ + do { \ + if (!(_expr)) { \ + fprintf(stderr, \ + "Assert FAILED at %s:%d:%s(): %s is FALSE.\n", \ + __FILE__, __LINE__, __FUNCTION__, #_expr); \ + return false; \ + } \ + } while (0) +#define ASSERT_FALSE(_expr) ASSERT_TRUE(!(_expr)) +#define ASSERT_EQ(_val1, _val2) ASSERT_TRUE((_val1) == (_val2)) +#define ASSERT_NE(_val1, _val2) ASSERT_TRUE((_val1) != (_val2)) + +static struct task_struct __current; + +struct task_struct *get_current(void) +{ + return &__current; +} + +unsigned long rlimit(unsigned int limit) +{ + return (unsigned long)-1; +} + +/* Helper function to simply allocate a VMA. */ +static struct vm_area_struct *alloc_vma(struct mm_struct *mm, + unsigned long start, + unsigned long end, + pgoff_t pgoff, + vm_flags_t flags) +{ + struct vm_area_struct *ret = vm_area_alloc(mm); + + if (ret == NULL) + return NULL; + + ret->vm_start = start; + ret->vm_end = end; + ret->vm_pgoff = pgoff; + ret->__vm_flags = flags; + vma_assert_detached(ret); + + return ret; +} + +/* Helper function to allocate a VMA and link it to the tree. */ +static int attach_vma(struct mm_struct *mm, struct vm_area_struct *vma) +{ + int res; + + res = vma_link(mm, vma); + if (!res) + vma_assert_attached(vma); + return res; +} + +static void detach_free_vma(struct vm_area_struct *vma) +{ + vma_mark_detached(vma); + vm_area_free(vma); +} + +/* Helper function to allocate a VMA and link it to the tree. */ +static struct vm_area_struct *alloc_and_link_vma(struct mm_struct *mm, + unsigned long start, + unsigned long end, + pgoff_t pgoff, + vm_flags_t flags) +{ + struct vm_area_struct *vma = alloc_vma(mm, start, end, pgoff, flags); + + if (vma == NULL) + return NULL; + + if (attach_vma(mm, vma)) { + detach_free_vma(vma); + return NULL; + } + + /* + * Reset this counter which we use to track whether writes have + * begun. Linking to the tree will have caused this to be incremented, + * which means we will get a false positive otherwise. + */ + vma->vm_lock_seq = UINT_MAX; + + return vma; +} + +/* Helper function which provides a wrapper around a merge new VMA operation. */ +static struct vm_area_struct *merge_new(struct vma_merge_struct *vmg) +{ + struct vm_area_struct *vma; + /* + * For convenience, get prev and next VMAs. Which the new VMA operation + * requires. + */ + vmg->next = vma_next(vmg->vmi); + vmg->prev = vma_prev(vmg->vmi); + vma_iter_next_range(vmg->vmi); + + vma = vma_merge_new_range(vmg); + if (vma) + vma_assert_attached(vma); + + return vma; +} + +/* + * Helper function which provides a wrapper around a merge existing VMA + * operation. + */ +static struct vm_area_struct *merge_existing(struct vma_merge_struct *vmg) +{ + struct vm_area_struct *vma; + + vma = vma_merge_existing_range(vmg); + if (vma) + vma_assert_attached(vma); + return vma; +} + +/* + * Helper function which provides a wrapper around the expansion of an existing + * VMA. + */ +static int expand_existing(struct vma_merge_struct *vmg) +{ + return vma_expand(vmg); +} + +/* + * Helper function to reset merge state the associated VMA iterator to a + * specified new range. + */ +static void vmg_set_range(struct vma_merge_struct *vmg, unsigned long start, + unsigned long end, pgoff_t pgoff, vm_flags_t flags) +{ + vma_iter_set(vmg->vmi, start); + + vmg->prev = NULL; + vmg->middle = NULL; + vmg->next = NULL; + vmg->target = NULL; + + vmg->start = start; + vmg->end = end; + vmg->pgoff = pgoff; + vmg->flags = flags; + + vmg->just_expand = false; + vmg->__remove_middle = false; + vmg->__remove_next = false; + vmg->__adjust_middle_start = false; + vmg->__adjust_next_start = false; +} + +/* Helper function to set both the VMG range and its anon_vma. */ +static void vmg_set_range_anon_vma(struct vma_merge_struct *vmg, unsigned long start, + unsigned long end, pgoff_t pgoff, vm_flags_t flags, + struct anon_vma *anon_vma) +{ + vmg_set_range(vmg, start, end, pgoff, flags); + vmg->anon_vma = anon_vma; +} + +/* + * Helper function to try to merge a new VMA. + * + * Update vmg and the iterator for it and try to merge, otherwise allocate a new + * VMA, link it to the maple tree and return it. + */ +static struct vm_area_struct *try_merge_new_vma(struct mm_struct *mm, + struct vma_merge_struct *vmg, + unsigned long start, unsigned long end, + pgoff_t pgoff, vm_flags_t flags, + bool *was_merged) +{ + struct vm_area_struct *merged; + + vmg_set_range(vmg, start, end, pgoff, flags); + + merged = merge_new(vmg); + if (merged) { + *was_merged = true; + ASSERT_EQ(vmg->state, VMA_MERGE_SUCCESS); + return merged; + } + + *was_merged = false; + + ASSERT_EQ(vmg->state, VMA_MERGE_NOMERGE); + + return alloc_and_link_vma(mm, start, end, pgoff, flags); +} + +/* + * Helper function to reset the dummy anon_vma to indicate it has not been + * duplicated. + */ +static void reset_dummy_anon_vma(void) +{ + dummy_anon_vma.was_cloned = false; + dummy_anon_vma.was_unlinked = false; +} + +/* + * Helper function to remove all VMAs and destroy the maple tree associated with + * a virtual address space. Returns a count of VMAs in the tree. + */ +static int cleanup_mm(struct mm_struct *mm, struct vma_iterator *vmi) +{ + struct vm_area_struct *vma; + int count = 0; + + fail_prealloc = false; + reset_dummy_anon_vma(); + + vma_iter_set(vmi, 0); + for_each_vma(*vmi, vma) { + detach_free_vma(vma); + count++; + } + + mtree_destroy(&mm->mm_mt); + mm->map_count = 0; + return count; +} + +/* Helper function to determine if VMA has had vma_start_write() performed. */ +static bool vma_write_started(struct vm_area_struct *vma) +{ + int seq = vma->vm_lock_seq; + + /* We reset after each check. */ + vma->vm_lock_seq = UINT_MAX; + + /* The vma_start_write() stub simply increments this value. */ + return seq > -1; +} + +/* Helper function providing a dummy vm_ops->close() method.*/ +static void dummy_close(struct vm_area_struct *) +{ +} + +static void __vma_set_dummy_anon_vma(struct vm_area_struct *vma, + struct anon_vma_chain *avc, + struct anon_vma *anon_vma) +{ + vma->anon_vma = anon_vma; + INIT_LIST_HEAD(&vma->anon_vma_chain); + list_add(&avc->same_vma, &vma->anon_vma_chain); + avc->anon_vma = vma->anon_vma; +} + +static void vma_set_dummy_anon_vma(struct vm_area_struct *vma, + struct anon_vma_chain *avc) +{ + __vma_set_dummy_anon_vma(vma, avc, &dummy_anon_vma); +} + +static bool test_simple_merge(void) +{ + struct vm_area_struct *vma; + unsigned long flags = VM_READ | VM_WRITE | VM_MAYREAD | VM_MAYWRITE; + struct mm_struct mm = {}; + struct vm_area_struct *vma_left = alloc_vma(&mm, 0, 0x1000, 0, flags); + struct vm_area_struct *vma_right = alloc_vma(&mm, 0x2000, 0x3000, 2, flags); + VMA_ITERATOR(vmi, &mm, 0x1000); + struct vma_merge_struct vmg = { + .mm = &mm, + .vmi = &vmi, + .start = 0x1000, + .end = 0x2000, + .flags = flags, + .pgoff = 1, + }; + + ASSERT_FALSE(attach_vma(&mm, vma_left)); + ASSERT_FALSE(attach_vma(&mm, vma_right)); + + vma = merge_new(&vmg); + ASSERT_NE(vma, NULL); + + ASSERT_EQ(vma->vm_start, 0); + ASSERT_EQ(vma->vm_end, 0x3000); + ASSERT_EQ(vma->vm_pgoff, 0); + ASSERT_EQ(vma->vm_flags, flags); + + detach_free_vma(vma); + mtree_destroy(&mm.mm_mt); + + return true; +} + +static bool test_simple_modify(void) +{ + struct vm_area_struct *vma; + unsigned long flags = VM_READ | VM_WRITE | VM_MAYREAD | VM_MAYWRITE; + struct mm_struct mm = {}; + struct vm_area_struct *init_vma = alloc_vma(&mm, 0, 0x3000, 0, flags); + VMA_ITERATOR(vmi, &mm, 0x1000); + + ASSERT_FALSE(attach_vma(&mm, init_vma)); + + /* + * The flags will not be changed, the vma_modify_flags() function + * performs the merge/split only. + */ + vma = vma_modify_flags(&vmi, init_vma, init_vma, + 0x1000, 0x2000, VM_READ | VM_MAYREAD); + ASSERT_NE(vma, NULL); + /* We modify the provided VMA, and on split allocate new VMAs. */ + ASSERT_EQ(vma, init_vma); + + ASSERT_EQ(vma->vm_start, 0x1000); + ASSERT_EQ(vma->vm_end, 0x2000); + ASSERT_EQ(vma->vm_pgoff, 1); + + /* + * Now walk through the three split VMAs and make sure they are as + * expected. + */ + + vma_iter_set(&vmi, 0); + vma = vma_iter_load(&vmi); + + ASSERT_EQ(vma->vm_start, 0); + ASSERT_EQ(vma->vm_end, 0x1000); + ASSERT_EQ(vma->vm_pgoff, 0); + + detach_free_vma(vma); + vma_iter_clear(&vmi); + + vma = vma_next(&vmi); + + ASSERT_EQ(vma->vm_start, 0x1000); + ASSERT_EQ(vma->vm_end, 0x2000); + ASSERT_EQ(vma->vm_pgoff, 1); + + detach_free_vma(vma); + vma_iter_clear(&vmi); + + vma = vma_next(&vmi); + + ASSERT_EQ(vma->vm_start, 0x2000); + ASSERT_EQ(vma->vm_end, 0x3000); + ASSERT_EQ(vma->vm_pgoff, 2); + + detach_free_vma(vma); + mtree_destroy(&mm.mm_mt); + + return true; +} + +static bool test_simple_expand(void) +{ + unsigned long flags = VM_READ | VM_WRITE | VM_MAYREAD | VM_MAYWRITE; + struct mm_struct mm = {}; + struct vm_area_struct *vma = alloc_vma(&mm, 0, 0x1000, 0, flags); + VMA_ITERATOR(vmi, &mm, 0); + struct vma_merge_struct vmg = { + .vmi = &vmi, + .middle = vma, + .start = 0, + .end = 0x3000, + .pgoff = 0, + }; + + ASSERT_FALSE(attach_vma(&mm, vma)); + + ASSERT_FALSE(expand_existing(&vmg)); + + ASSERT_EQ(vma->vm_start, 0); + ASSERT_EQ(vma->vm_end, 0x3000); + ASSERT_EQ(vma->vm_pgoff, 0); + + detach_free_vma(vma); + mtree_destroy(&mm.mm_mt); + + return true; +} + +static bool test_simple_shrink(void) +{ + unsigned long flags = VM_READ | VM_WRITE | VM_MAYREAD | VM_MAYWRITE; + struct mm_struct mm = {}; + struct vm_area_struct *vma = alloc_vma(&mm, 0, 0x3000, 0, flags); + VMA_ITERATOR(vmi, &mm, 0); + + ASSERT_FALSE(attach_vma(&mm, vma)); + + ASSERT_FALSE(vma_shrink(&vmi, vma, 0, 0x1000, 0)); + + ASSERT_EQ(vma->vm_start, 0); + ASSERT_EQ(vma->vm_end, 0x1000); + ASSERT_EQ(vma->vm_pgoff, 0); + + detach_free_vma(vma); + mtree_destroy(&mm.mm_mt); + + return true; +} + +static bool test_merge_new(void) +{ + unsigned long flags = VM_READ | VM_WRITE | VM_MAYREAD | VM_MAYWRITE; + struct mm_struct mm = {}; + VMA_ITERATOR(vmi, &mm, 0); + struct vma_merge_struct vmg = { + .mm = &mm, + .vmi = &vmi, + }; + struct anon_vma_chain dummy_anon_vma_chain_a = { + .anon_vma = &dummy_anon_vma, + }; + struct anon_vma_chain dummy_anon_vma_chain_b = { + .anon_vma = &dummy_anon_vma, + }; + struct anon_vma_chain dummy_anon_vma_chain_c = { + .anon_vma = &dummy_anon_vma, + }; + struct anon_vma_chain dummy_anon_vma_chain_d = { + .anon_vma = &dummy_anon_vma, + }; + const struct vm_operations_struct vm_ops = { + .close = dummy_close, + }; + int count; + struct vm_area_struct *vma, *vma_a, *vma_b, *vma_c, *vma_d; + bool merged; + + /* + * 0123456789abc + * AA B CC + */ + vma_a = alloc_and_link_vma(&mm, 0, 0x2000, 0, flags); + ASSERT_NE(vma_a, NULL); + /* We give each VMA a single avc so we can test anon_vma duplication. */ + INIT_LIST_HEAD(&vma_a->anon_vma_chain); + list_add(&dummy_anon_vma_chain_a.same_vma, &vma_a->anon_vma_chain); + + vma_b = alloc_and_link_vma(&mm, 0x3000, 0x4000, 3, flags); + ASSERT_NE(vma_b, NULL); + INIT_LIST_HEAD(&vma_b->anon_vma_chain); + list_add(&dummy_anon_vma_chain_b.same_vma, &vma_b->anon_vma_chain); + + vma_c = alloc_and_link_vma(&mm, 0xb000, 0xc000, 0xb, flags); + ASSERT_NE(vma_c, NULL); + INIT_LIST_HEAD(&vma_c->anon_vma_chain); + list_add(&dummy_anon_vma_chain_c.same_vma, &vma_c->anon_vma_chain); + + /* + * NO merge. + * + * 0123456789abc + * AA B ** CC + */ + vma_d = try_merge_new_vma(&mm, &vmg, 0x7000, 0x9000, 7, flags, &merged); + ASSERT_NE(vma_d, NULL); + INIT_LIST_HEAD(&vma_d->anon_vma_chain); + list_add(&dummy_anon_vma_chain_d.same_vma, &vma_d->anon_vma_chain); + ASSERT_FALSE(merged); + ASSERT_EQ(mm.map_count, 4); + + /* + * Merge BOTH sides. + * + * 0123456789abc + * AA*B DD CC + */ + vma_a->vm_ops = &vm_ops; /* This should have no impact. */ + vma_b->anon_vma = &dummy_anon_vma; + vma = try_merge_new_vma(&mm, &vmg, 0x2000, 0x3000, 2, flags, &merged); + ASSERT_EQ(vma, vma_a); + /* Merge with A, delete B. */ + ASSERT_TRUE(merged); + ASSERT_EQ(vma->vm_start, 0); + ASSERT_EQ(vma->vm_end, 0x4000); + ASSERT_EQ(vma->vm_pgoff, 0); + ASSERT_EQ(vma->anon_vma, &dummy_anon_vma); + ASSERT_TRUE(vma_write_started(vma)); + ASSERT_EQ(mm.map_count, 3); + + /* + * Merge to PREVIOUS VMA. + * + * 0123456789abc + * AAAA* DD CC + */ + vma = try_merge_new_vma(&mm, &vmg, 0x4000, 0x5000, 4, flags, &merged); + ASSERT_EQ(vma, vma_a); + /* Extend A. */ + ASSERT_TRUE(merged); + ASSERT_EQ(vma->vm_start, 0); + ASSERT_EQ(vma->vm_end, 0x5000); + ASSERT_EQ(vma->vm_pgoff, 0); + ASSERT_EQ(vma->anon_vma, &dummy_anon_vma); + ASSERT_TRUE(vma_write_started(vma)); + ASSERT_EQ(mm.map_count, 3); + + /* + * Merge to NEXT VMA. + * + * 0123456789abc + * AAAAA *DD CC + */ + vma_d->anon_vma = &dummy_anon_vma; + vma_d->vm_ops = &vm_ops; /* This should have no impact. */ + vma = try_merge_new_vma(&mm, &vmg, 0x6000, 0x7000, 6, flags, &merged); + ASSERT_EQ(vma, vma_d); + /* Prepend. */ + ASSERT_TRUE(merged); + ASSERT_EQ(vma->vm_start, 0x6000); + ASSERT_EQ(vma->vm_end, 0x9000); + ASSERT_EQ(vma->vm_pgoff, 6); + ASSERT_EQ(vma->anon_vma, &dummy_anon_vma); + ASSERT_TRUE(vma_write_started(vma)); + ASSERT_EQ(mm.map_count, 3); + + /* + * Merge BOTH sides. + * + * 0123456789abc + * AAAAA*DDD CC + */ + vma_d->vm_ops = NULL; /* This would otherwise degrade the merge. */ + vma = try_merge_new_vma(&mm, &vmg, 0x5000, 0x6000, 5, flags, &merged); + ASSERT_EQ(vma, vma_a); + /* Merge with A, delete D. */ + ASSERT_TRUE(merged); + ASSERT_EQ(vma->vm_start, 0); + ASSERT_EQ(vma->vm_end, 0x9000); + ASSERT_EQ(vma->vm_pgoff, 0); + ASSERT_EQ(vma->anon_vma, &dummy_anon_vma); + ASSERT_TRUE(vma_write_started(vma)); + ASSERT_EQ(mm.map_count, 2); + + /* + * Merge to NEXT VMA. + * + * 0123456789abc + * AAAAAAAAA *CC + */ + vma_c->anon_vma = &dummy_anon_vma; + vma = try_merge_new_vma(&mm, &vmg, 0xa000, 0xb000, 0xa, flags, &merged); + ASSERT_EQ(vma, vma_c); + /* Prepend C. */ + ASSERT_TRUE(merged); + ASSERT_EQ(vma->vm_start, 0xa000); + ASSERT_EQ(vma->vm_end, 0xc000); + ASSERT_EQ(vma->vm_pgoff, 0xa); + ASSERT_EQ(vma->anon_vma, &dummy_anon_vma); + ASSERT_TRUE(vma_write_started(vma)); + ASSERT_EQ(mm.map_count, 2); + + /* + * Merge BOTH sides. + * + * 0123456789abc + * AAAAAAAAA*CCC + */ + vma = try_merge_new_vma(&mm, &vmg, 0x9000, 0xa000, 0x9, flags, &merged); + ASSERT_EQ(vma, vma_a); + /* Extend A and delete C. */ + ASSERT_TRUE(merged); + ASSERT_EQ(vma->vm_start, 0); + ASSERT_EQ(vma->vm_end, 0xc000); + ASSERT_EQ(vma->vm_pgoff, 0); + ASSERT_EQ(vma->anon_vma, &dummy_anon_vma); + ASSERT_TRUE(vma_write_started(vma)); + ASSERT_EQ(mm.map_count, 1); + + /* + * Final state. + * + * 0123456789abc + * AAAAAAAAAAAAA + */ + + count = 0; + vma_iter_set(&vmi, 0); + for_each_vma(vmi, vma) { + ASSERT_NE(vma, NULL); + ASSERT_EQ(vma->vm_start, 0); + ASSERT_EQ(vma->vm_end, 0xc000); + ASSERT_EQ(vma->vm_pgoff, 0); + ASSERT_EQ(vma->anon_vma, &dummy_anon_vma); + + detach_free_vma(vma); + count++; + } + + /* Should only have one VMA left (though freed) after all is done.*/ + ASSERT_EQ(count, 1); + + mtree_destroy(&mm.mm_mt); + return true; +} + +static bool test_vma_merge_special_flags(void) +{ + unsigned long flags = VM_READ | VM_WRITE | VM_MAYREAD | VM_MAYWRITE; + struct mm_struct mm = {}; + VMA_ITERATOR(vmi, &mm, 0); + struct vma_merge_struct vmg = { + .mm = &mm, + .vmi = &vmi, + }; + vm_flags_t special_flags[] = { VM_IO, VM_DONTEXPAND, VM_PFNMAP, VM_MIXEDMAP }; + vm_flags_t all_special_flags = 0; + int i; + struct vm_area_struct *vma_left, *vma; + + /* Make sure there aren't new VM_SPECIAL flags. */ + for (i = 0; i < ARRAY_SIZE(special_flags); i++) { + all_special_flags |= special_flags[i]; + } + ASSERT_EQ(all_special_flags, VM_SPECIAL); + + /* + * 01234 + * AAA + */ + vma_left = alloc_and_link_vma(&mm, 0, 0x3000, 0, flags); + ASSERT_NE(vma_left, NULL); + + /* 1. Set up new VMA with special flag that would otherwise merge. */ + + /* + * 01234 + * AAA* + * + * This should merge if not for the VM_SPECIAL flag. + */ + vmg_set_range(&vmg, 0x3000, 0x4000, 3, flags); + for (i = 0; i < ARRAY_SIZE(special_flags); i++) { + vm_flags_t special_flag = special_flags[i]; + + vma_left->__vm_flags = flags | special_flag; + vmg.flags = flags | special_flag; + vma = merge_new(&vmg); + ASSERT_EQ(vma, NULL); + ASSERT_EQ(vmg.state, VMA_MERGE_NOMERGE); + } + + /* 2. Modify VMA with special flag that would otherwise merge. */ + + /* + * 01234 + * AAAB + * + * Create a VMA to modify. + */ + vma = alloc_and_link_vma(&mm, 0x3000, 0x4000, 3, flags); + ASSERT_NE(vma, NULL); + vmg.middle = vma; + + for (i = 0; i < ARRAY_SIZE(special_flags); i++) { + vm_flags_t special_flag = special_flags[i]; + + vma_left->__vm_flags = flags | special_flag; + vmg.flags = flags | special_flag; + vma = merge_existing(&vmg); + ASSERT_EQ(vma, NULL); + ASSERT_EQ(vmg.state, VMA_MERGE_NOMERGE); + } + + cleanup_mm(&mm, &vmi); + return true; +} + +static bool test_vma_merge_with_close(void) +{ + unsigned long flags = VM_READ | VM_WRITE | VM_MAYREAD | VM_MAYWRITE; + struct mm_struct mm = {}; + VMA_ITERATOR(vmi, &mm, 0); + struct vma_merge_struct vmg = { + .mm = &mm, + .vmi = &vmi, + }; + const struct vm_operations_struct vm_ops = { + .close = dummy_close, + }; + struct vm_area_struct *vma_prev, *vma_next, *vma; + + /* + * When merging VMAs we are not permitted to remove any VMA that has a + * vm_ops->close() hook. + * + * Considering the two possible adjacent VMAs to which a VMA can be + * merged: + * + * [ prev ][ vma ][ next ] + * + * In no case will we need to delete prev. If the operation is + * mergeable, then prev will be extended with one or both of vma and + * next deleted. + * + * As a result, during initial mergeability checks, only + * can_vma_merge_before() (which implies the VMA being merged with is + * 'next' as shown above) bothers to check to see whether the next VMA + * has a vm_ops->close() callback that will need to be called when + * removed. + * + * If it does, then we cannot merge as the resources that the close() + * operation potentially clears down are tied only to the existing VMA + * range and we have no way of extending those to the nearly merged one. + * + * We must consider two scenarios: + * + * A. + * + * vm_ops->close: - - !NULL + * [ prev ][ vma ][ next ] + * + * Where prev may or may not be present/mergeable. + * + * This is picked up by a specific check in can_vma_merge_before(). + * + * B. + * + * vm_ops->close: - !NULL + * [ prev ][ vma ] + * + * Where prev and vma are present and mergeable. + * + * This is picked up by a specific check in the modified VMA merge. + * + * IMPORTANT NOTE: We make the assumption that the following case: + * + * - !NULL NULL + * [ prev ][ vma ][ next ] + * + * Cannot occur, because vma->vm_ops being the same implies the same + * vma->vm_file, and therefore this would mean that next->vm_ops->close + * would be set too, and thus scenario A would pick this up. + */ + + /* + * The only case of a new VMA merge that results in a VMA being deleted + * is one where both the previous and next VMAs are merged - in this + * instance the next VMA is deleted, and the previous VMA is extended. + * + * If we are unable to do so, we reduce the operation to simply + * extending the prev VMA and not merging next. + * + * 0123456789 + * PPP**NNNN + * -> + * 0123456789 + * PPPPPPNNN + */ + + vma_prev = alloc_and_link_vma(&mm, 0, 0x3000, 0, flags); + vma_next = alloc_and_link_vma(&mm, 0x5000, 0x9000, 5, flags); + vma_next->vm_ops = &vm_ops; + + vmg_set_range(&vmg, 0x3000, 0x5000, 3, flags); + ASSERT_EQ(merge_new(&vmg), vma_prev); + ASSERT_EQ(vmg.state, VMA_MERGE_SUCCESS); + ASSERT_EQ(vma_prev->vm_start, 0); + ASSERT_EQ(vma_prev->vm_end, 0x5000); + ASSERT_EQ(vma_prev->vm_pgoff, 0); + + ASSERT_EQ(cleanup_mm(&mm, &vmi), 2); + + /* + * When modifying an existing VMA there are further cases where we + * delete VMAs. + * + * <> + * 0123456789 + * PPPVV + * + * In this instance, if vma has a close hook, the merge simply cannot + * proceed. + */ + + vma_prev = alloc_and_link_vma(&mm, 0, 0x3000, 0, flags); + vma = alloc_and_link_vma(&mm, 0x3000, 0x5000, 3, flags); + vma->vm_ops = &vm_ops; + + vmg_set_range(&vmg, 0x3000, 0x5000, 3, flags); + vmg.prev = vma_prev; + vmg.middle = vma; + + /* + * The VMA being modified in a way that would otherwise merge should + * also fail. + */ + ASSERT_EQ(merge_existing(&vmg), NULL); + ASSERT_EQ(vmg.state, VMA_MERGE_NOMERGE); + + ASSERT_EQ(cleanup_mm(&mm, &vmi), 2); + + /* + * This case is mirrored if merging with next. + * + * <> + * 0123456789 + * VVNNNN + * + * In this instance, if vma has a close hook, the merge simply cannot + * proceed. + */ + + vma = alloc_and_link_vma(&mm, 0x3000, 0x5000, 3, flags); + vma_next = alloc_and_link_vma(&mm, 0x5000, 0x9000, 5, flags); + vma->vm_ops = &vm_ops; + + vmg_set_range(&vmg, 0x3000, 0x5000, 3, flags); + vmg.middle = vma; + ASSERT_EQ(merge_existing(&vmg), NULL); + /* + * Initially this is misapprehended as an out of memory report, as the + * close() check is handled in the same way as anon_vma duplication + * failures, however a subsequent patch resolves this. + */ + ASSERT_EQ(vmg.state, VMA_MERGE_NOMERGE); + + ASSERT_EQ(cleanup_mm(&mm, &vmi), 2); + + /* + * Finally, we consider two variants of the case where we modify a VMA + * to merge with both the previous and next VMAs. + * + * The first variant is where vma has a close hook. In this instance, no + * merge can proceed. + * + * <> + * 0123456789 + * PPPVVNNNN + */ + + vma_prev = alloc_and_link_vma(&mm, 0, 0x3000, 0, flags); + vma = alloc_and_link_vma(&mm, 0x3000, 0x5000, 3, flags); + vma_next = alloc_and_link_vma(&mm, 0x5000, 0x9000, 5, flags); + vma->vm_ops = &vm_ops; + + vmg_set_range(&vmg, 0x3000, 0x5000, 3, flags); + vmg.prev = vma_prev; + vmg.middle = vma; + + ASSERT_EQ(merge_existing(&vmg), NULL); + ASSERT_EQ(vmg.state, VMA_MERGE_NOMERGE); + + ASSERT_EQ(cleanup_mm(&mm, &vmi), 3); + + /* + * The second variant is where next has a close hook. In this instance, + * we reduce the operation to a merge between prev and vma. + * + * <> + * 0123456789 + * PPPVVNNNN + * -> + * 0123456789 + * PPPPPNNNN + */ + + vma_prev = alloc_and_link_vma(&mm, 0, 0x3000, 0, flags); + vma = alloc_and_link_vma(&mm, 0x3000, 0x5000, 3, flags); + vma_next = alloc_and_link_vma(&mm, 0x5000, 0x9000, 5, flags); + vma_next->vm_ops = &vm_ops; + + vmg_set_range(&vmg, 0x3000, 0x5000, 3, flags); + vmg.prev = vma_prev; + vmg.middle = vma; + + ASSERT_EQ(merge_existing(&vmg), vma_prev); + ASSERT_EQ(vmg.state, VMA_MERGE_SUCCESS); + ASSERT_EQ(vma_prev->vm_start, 0); + ASSERT_EQ(vma_prev->vm_end, 0x5000); + ASSERT_EQ(vma_prev->vm_pgoff, 0); + + ASSERT_EQ(cleanup_mm(&mm, &vmi), 2); + + return true; +} + +static bool test_vma_merge_new_with_close(void) +{ + unsigned long flags = VM_READ | VM_WRITE | VM_MAYREAD | VM_MAYWRITE; + struct mm_struct mm = {}; + VMA_ITERATOR(vmi, &mm, 0); + struct vma_merge_struct vmg = { + .mm = &mm, + .vmi = &vmi, + }; + struct vm_area_struct *vma_prev = alloc_and_link_vma(&mm, 0, 0x2000, 0, flags); + struct vm_area_struct *vma_next = alloc_and_link_vma(&mm, 0x5000, 0x7000, 5, flags); + const struct vm_operations_struct vm_ops = { + .close = dummy_close, + }; + struct vm_area_struct *vma; + + /* + * We should allow the partial merge of a proposed new VMA if the + * surrounding VMAs have vm_ops->close() hooks (but are otherwise + * compatible), e.g.: + * + * New VMA + * A v-------v B + * |-----| |-----| + * close close + * + * Since the rule is to not DELETE a VMA with a close operation, this + * should be permitted, only rather than expanding A and deleting B, we + * should simply expand A and leave B intact, e.g.: + * + * New VMA + * A B + * |------------||-----| + * close close + */ + + /* Have prev and next have a vm_ops->close() hook. */ + vma_prev->vm_ops = &vm_ops; + vma_next->vm_ops = &vm_ops; + + vmg_set_range(&vmg, 0x2000, 0x5000, 2, flags); + vma = merge_new(&vmg); + ASSERT_NE(vma, NULL); + ASSERT_EQ(vmg.state, VMA_MERGE_SUCCESS); + ASSERT_EQ(vma->vm_start, 0); + ASSERT_EQ(vma->vm_end, 0x5000); + ASSERT_EQ(vma->vm_pgoff, 0); + ASSERT_EQ(vma->vm_ops, &vm_ops); + ASSERT_TRUE(vma_write_started(vma)); + ASSERT_EQ(mm.map_count, 2); + + cleanup_mm(&mm, &vmi); + return true; +} + +static bool test_merge_existing(void) +{ + unsigned long flags = VM_READ | VM_WRITE | VM_MAYREAD | VM_MAYWRITE; + struct mm_struct mm = {}; + VMA_ITERATOR(vmi, &mm, 0); + struct vm_area_struct *vma, *vma_prev, *vma_next; + struct vma_merge_struct vmg = { + .mm = &mm, + .vmi = &vmi, + }; + const struct vm_operations_struct vm_ops = { + .close = dummy_close, + }; + struct anon_vma_chain avc = {}; + + /* + * Merge right case - partial span. + * + * <-> + * 0123456789 + * VVVVNNN + * -> + * 0123456789 + * VNNNNNN + */ + vma = alloc_and_link_vma(&mm, 0x2000, 0x6000, 2, flags); + vma->vm_ops = &vm_ops; /* This should have no impact. */ + vma_next = alloc_and_link_vma(&mm, 0x6000, 0x9000, 6, flags); + vma_next->vm_ops = &vm_ops; /* This should have no impact. */ + vmg_set_range_anon_vma(&vmg, 0x3000, 0x6000, 3, flags, &dummy_anon_vma); + vmg.middle = vma; + vmg.prev = vma; + vma_set_dummy_anon_vma(vma, &avc); + ASSERT_EQ(merge_existing(&vmg), vma_next); + ASSERT_EQ(vmg.state, VMA_MERGE_SUCCESS); + ASSERT_EQ(vma_next->vm_start, 0x3000); + ASSERT_EQ(vma_next->vm_end, 0x9000); + ASSERT_EQ(vma_next->vm_pgoff, 3); + ASSERT_EQ(vma_next->anon_vma, &dummy_anon_vma); + ASSERT_EQ(vma->vm_start, 0x2000); + ASSERT_EQ(vma->vm_end, 0x3000); + ASSERT_EQ(vma->vm_pgoff, 2); + ASSERT_TRUE(vma_write_started(vma)); + ASSERT_TRUE(vma_write_started(vma_next)); + ASSERT_EQ(mm.map_count, 2); + + /* Clear down and reset. */ + ASSERT_EQ(cleanup_mm(&mm, &vmi), 2); + + /* + * Merge right case - full span. + * + * <--> + * 0123456789 + * VVVVNNN + * -> + * 0123456789 + * NNNNNNN + */ + vma = alloc_and_link_vma(&mm, 0x2000, 0x6000, 2, flags); + vma_next = alloc_and_link_vma(&mm, 0x6000, 0x9000, 6, flags); + vma_next->vm_ops = &vm_ops; /* This should have no impact. */ + vmg_set_range_anon_vma(&vmg, 0x2000, 0x6000, 2, flags, &dummy_anon_vma); + vmg.middle = vma; + vma_set_dummy_anon_vma(vma, &avc); + ASSERT_EQ(merge_existing(&vmg), vma_next); + ASSERT_EQ(vmg.state, VMA_MERGE_SUCCESS); + ASSERT_EQ(vma_next->vm_start, 0x2000); + ASSERT_EQ(vma_next->vm_end, 0x9000); + ASSERT_EQ(vma_next->vm_pgoff, 2); + ASSERT_EQ(vma_next->anon_vma, &dummy_anon_vma); + ASSERT_TRUE(vma_write_started(vma_next)); + ASSERT_EQ(mm.map_count, 1); + + /* Clear down and reset. We should have deleted vma. */ + ASSERT_EQ(cleanup_mm(&mm, &vmi), 1); + + /* + * Merge left case - partial span. + * + * <-> + * 0123456789 + * PPPVVVV + * -> + * 0123456789 + * PPPPPPV + */ + vma_prev = alloc_and_link_vma(&mm, 0, 0x3000, 0, flags); + vma_prev->vm_ops = &vm_ops; /* This should have no impact. */ + vma = alloc_and_link_vma(&mm, 0x3000, 0x7000, 3, flags); + vma->vm_ops = &vm_ops; /* This should have no impact. */ + vmg_set_range_anon_vma(&vmg, 0x3000, 0x6000, 3, flags, &dummy_anon_vma); + vmg.prev = vma_prev; + vmg.middle = vma; + vma_set_dummy_anon_vma(vma, &avc); + ASSERT_EQ(merge_existing(&vmg), vma_prev); + ASSERT_EQ(vmg.state, VMA_MERGE_SUCCESS); + ASSERT_EQ(vma_prev->vm_start, 0); + ASSERT_EQ(vma_prev->vm_end, 0x6000); + ASSERT_EQ(vma_prev->vm_pgoff, 0); + ASSERT_EQ(vma_prev->anon_vma, &dummy_anon_vma); + ASSERT_EQ(vma->vm_start, 0x6000); + ASSERT_EQ(vma->vm_end, 0x7000); + ASSERT_EQ(vma->vm_pgoff, 6); + ASSERT_TRUE(vma_write_started(vma_prev)); + ASSERT_TRUE(vma_write_started(vma)); + ASSERT_EQ(mm.map_count, 2); + + /* Clear down and reset. */ + ASSERT_EQ(cleanup_mm(&mm, &vmi), 2); + + /* + * Merge left case - full span. + * + * <--> + * 0123456789 + * PPPVVVV + * -> + * 0123456789 + * PPPPPPP + */ + vma_prev = alloc_and_link_vma(&mm, 0, 0x3000, 0, flags); + vma_prev->vm_ops = &vm_ops; /* This should have no impact. */ + vma = alloc_and_link_vma(&mm, 0x3000, 0x7000, 3, flags); + vmg_set_range_anon_vma(&vmg, 0x3000, 0x7000, 3, flags, &dummy_anon_vma); + vmg.prev = vma_prev; + vmg.middle = vma; + vma_set_dummy_anon_vma(vma, &avc); + ASSERT_EQ(merge_existing(&vmg), vma_prev); + ASSERT_EQ(vmg.state, VMA_MERGE_SUCCESS); + ASSERT_EQ(vma_prev->vm_start, 0); + ASSERT_EQ(vma_prev->vm_end, 0x7000); + ASSERT_EQ(vma_prev->vm_pgoff, 0); + ASSERT_EQ(vma_prev->anon_vma, &dummy_anon_vma); + ASSERT_TRUE(vma_write_started(vma_prev)); + ASSERT_EQ(mm.map_count, 1); + + /* Clear down and reset. We should have deleted vma. */ + ASSERT_EQ(cleanup_mm(&mm, &vmi), 1); + + /* + * Merge both case. + * + * <--> + * 0123456789 + * PPPVVVVNNN + * -> + * 0123456789 + * PPPPPPPPPP + */ + vma_prev = alloc_and_link_vma(&mm, 0, 0x3000, 0, flags); + vma_prev->vm_ops = &vm_ops; /* This should have no impact. */ + vma = alloc_and_link_vma(&mm, 0x3000, 0x7000, 3, flags); + vma_next = alloc_and_link_vma(&mm, 0x7000, 0x9000, 7, flags); + vmg_set_range_anon_vma(&vmg, 0x3000, 0x7000, 3, flags, &dummy_anon_vma); + vmg.prev = vma_prev; + vmg.middle = vma; + vma_set_dummy_anon_vma(vma, &avc); + ASSERT_EQ(merge_existing(&vmg), vma_prev); + ASSERT_EQ(vmg.state, VMA_MERGE_SUCCESS); + ASSERT_EQ(vma_prev->vm_start, 0); + ASSERT_EQ(vma_prev->vm_end, 0x9000); + ASSERT_EQ(vma_prev->vm_pgoff, 0); + ASSERT_EQ(vma_prev->anon_vma, &dummy_anon_vma); + ASSERT_TRUE(vma_write_started(vma_prev)); + ASSERT_EQ(mm.map_count, 1); + + /* Clear down and reset. We should have deleted prev and next. */ + ASSERT_EQ(cleanup_mm(&mm, &vmi), 1); + + /* + * Non-merge ranges. the modified VMA merge operation assumes that the + * caller always specifies ranges within the input VMA so we need only + * examine these cases. + * + * - + * - + * - + * <-> + * <> + * <> + * 0123456789a + * PPPVVVVVNNN + */ + + vma_prev = alloc_and_link_vma(&mm, 0, 0x3000, 0, flags); + vma = alloc_and_link_vma(&mm, 0x3000, 0x8000, 3, flags); + vma_next = alloc_and_link_vma(&mm, 0x8000, 0xa000, 8, flags); + + vmg_set_range(&vmg, 0x4000, 0x5000, 4, flags); + vmg.prev = vma; + vmg.middle = vma; + ASSERT_EQ(merge_existing(&vmg), NULL); + ASSERT_EQ(vmg.state, VMA_MERGE_NOMERGE); + + vmg_set_range(&vmg, 0x5000, 0x6000, 5, flags); + vmg.prev = vma; + vmg.middle = vma; + ASSERT_EQ(merge_existing(&vmg), NULL); + ASSERT_EQ(vmg.state, VMA_MERGE_NOMERGE); + + vmg_set_range(&vmg, 0x6000, 0x7000, 6, flags); + vmg.prev = vma; + vmg.middle = vma; + ASSERT_EQ(merge_existing(&vmg), NULL); + ASSERT_EQ(vmg.state, VMA_MERGE_NOMERGE); + + vmg_set_range(&vmg, 0x4000, 0x7000, 4, flags); + vmg.prev = vma; + vmg.middle = vma; + ASSERT_EQ(merge_existing(&vmg), NULL); + ASSERT_EQ(vmg.state, VMA_MERGE_NOMERGE); + + vmg_set_range(&vmg, 0x4000, 0x6000, 4, flags); + vmg.prev = vma; + vmg.middle = vma; + ASSERT_EQ(merge_existing(&vmg), NULL); + ASSERT_EQ(vmg.state, VMA_MERGE_NOMERGE); + + vmg_set_range(&vmg, 0x5000, 0x6000, 5, flags); + vmg.prev = vma; + vmg.middle = vma; + ASSERT_EQ(merge_existing(&vmg), NULL); + ASSERT_EQ(vmg.state, VMA_MERGE_NOMERGE); + + ASSERT_EQ(cleanup_mm(&mm, &vmi), 3); + + return true; +} + +static bool test_anon_vma_non_mergeable(void) +{ + unsigned long flags = VM_READ | VM_WRITE | VM_MAYREAD | VM_MAYWRITE; + struct mm_struct mm = {}; + VMA_ITERATOR(vmi, &mm, 0); + struct vm_area_struct *vma, *vma_prev, *vma_next; + struct vma_merge_struct vmg = { + .mm = &mm, + .vmi = &vmi, + }; + struct anon_vma_chain dummy_anon_vma_chain_1 = {}; + struct anon_vma_chain dummy_anon_vma_chain_2 = {}; + struct anon_vma dummy_anon_vma_2; + + /* + * In the case of modified VMA merge, merging both left and right VMAs + * but where prev and next have incompatible anon_vma objects, we revert + * to a merge of prev and VMA: + * + * <--> + * 0123456789 + * PPPVVVVNNN + * -> + * 0123456789 + * PPPPPPPNNN + */ + vma_prev = alloc_and_link_vma(&mm, 0, 0x3000, 0, flags); + vma = alloc_and_link_vma(&mm, 0x3000, 0x7000, 3, flags); + vma_next = alloc_and_link_vma(&mm, 0x7000, 0x9000, 7, flags); + + /* + * Give both prev and next single anon_vma_chain fields, so they will + * merge with the NULL vmg->anon_vma. + * + * However, when prev is compared to next, the merge should fail. + */ + vmg_set_range_anon_vma(&vmg, 0x3000, 0x7000, 3, flags, NULL); + vmg.prev = vma_prev; + vmg.middle = vma; + vma_set_dummy_anon_vma(vma_prev, &dummy_anon_vma_chain_1); + __vma_set_dummy_anon_vma(vma_next, &dummy_anon_vma_chain_2, &dummy_anon_vma_2); + + ASSERT_EQ(merge_existing(&vmg), vma_prev); + ASSERT_EQ(vmg.state, VMA_MERGE_SUCCESS); + ASSERT_EQ(vma_prev->vm_start, 0); + ASSERT_EQ(vma_prev->vm_end, 0x7000); + ASSERT_EQ(vma_prev->vm_pgoff, 0); + ASSERT_TRUE(vma_write_started(vma_prev)); + ASSERT_FALSE(vma_write_started(vma_next)); + + /* Clear down and reset. */ + ASSERT_EQ(cleanup_mm(&mm, &vmi), 2); + + /* + * Now consider the new VMA case. This is equivalent, only adding a new + * VMA in a gap between prev and next. + * + * <--> + * 0123456789 + * PPP****NNN + * -> + * 0123456789 + * PPPPPPPNNN + */ + vma_prev = alloc_and_link_vma(&mm, 0, 0x3000, 0, flags); + vma_next = alloc_and_link_vma(&mm, 0x7000, 0x9000, 7, flags); + + vmg_set_range_anon_vma(&vmg, 0x3000, 0x7000, 3, flags, NULL); + vmg.prev = vma_prev; + vma_set_dummy_anon_vma(vma_prev, &dummy_anon_vma_chain_1); + __vma_set_dummy_anon_vma(vma_next, &dummy_anon_vma_chain_2, &dummy_anon_vma_2); + + vmg.anon_vma = NULL; + ASSERT_EQ(merge_new(&vmg), vma_prev); + ASSERT_EQ(vmg.state, VMA_MERGE_SUCCESS); + ASSERT_EQ(vma_prev->vm_start, 0); + ASSERT_EQ(vma_prev->vm_end, 0x7000); + ASSERT_EQ(vma_prev->vm_pgoff, 0); + ASSERT_TRUE(vma_write_started(vma_prev)); + ASSERT_FALSE(vma_write_started(vma_next)); + + /* Final cleanup. */ + ASSERT_EQ(cleanup_mm(&mm, &vmi), 2); + + return true; +} + +static bool test_dup_anon_vma(void) +{ + unsigned long flags = VM_READ | VM_WRITE | VM_MAYREAD | VM_MAYWRITE; + struct mm_struct mm = {}; + VMA_ITERATOR(vmi, &mm, 0); + struct vma_merge_struct vmg = { + .mm = &mm, + .vmi = &vmi, + }; + struct anon_vma_chain dummy_anon_vma_chain = { + .anon_vma = &dummy_anon_vma, + }; + struct vm_area_struct *vma_prev, *vma_next, *vma; + + reset_dummy_anon_vma(); + + /* + * Expanding a VMA delete the next one duplicates next's anon_vma and + * assigns it to the expanded VMA. + * + * This covers new VMA merging, as these operations amount to a VMA + * expand. + */ + vma_prev = alloc_and_link_vma(&mm, 0, 0x3000, 0, flags); + vma_next = alloc_and_link_vma(&mm, 0x3000, 0x5000, 3, flags); + vma_next->anon_vma = &dummy_anon_vma; + + vmg_set_range(&vmg, 0, 0x5000, 0, flags); + vmg.middle = vma_prev; + vmg.next = vma_next; + + ASSERT_EQ(expand_existing(&vmg), 0); + + /* Will have been cloned. */ + ASSERT_EQ(vma_prev->anon_vma, &dummy_anon_vma); + ASSERT_TRUE(vma_prev->anon_vma->was_cloned); + + /* Cleanup ready for next run. */ + cleanup_mm(&mm, &vmi); + + /* + * next has anon_vma, we assign to prev. + * + * |<----->| + * |-------*********-------| + * prev vma next + * extend delete delete + */ + + vma_prev = alloc_and_link_vma(&mm, 0, 0x3000, 0, flags); + vma = alloc_and_link_vma(&mm, 0x3000, 0x5000, 3, flags); + vma_next = alloc_and_link_vma(&mm, 0x5000, 0x8000, 5, flags); + + /* Initialise avc so mergeability check passes. */ + INIT_LIST_HEAD(&vma_next->anon_vma_chain); + list_add(&dummy_anon_vma_chain.same_vma, &vma_next->anon_vma_chain); + + vma_next->anon_vma = &dummy_anon_vma; + vmg_set_range(&vmg, 0x3000, 0x5000, 3, flags); + vmg.prev = vma_prev; + vmg.middle = vma; + + ASSERT_EQ(merge_existing(&vmg), vma_prev); + ASSERT_EQ(vmg.state, VMA_MERGE_SUCCESS); + + ASSERT_EQ(vma_prev->vm_start, 0); + ASSERT_EQ(vma_prev->vm_end, 0x8000); + + ASSERT_EQ(vma_prev->anon_vma, &dummy_anon_vma); + ASSERT_TRUE(vma_prev->anon_vma->was_cloned); + + cleanup_mm(&mm, &vmi); + + /* + * vma has anon_vma, we assign to prev. + * + * |<----->| + * |-------*********-------| + * prev vma next + * extend delete delete + */ + + vma_prev = alloc_and_link_vma(&mm, 0, 0x3000, 0, flags); + vma = alloc_and_link_vma(&mm, 0x3000, 0x5000, 3, flags); + vma_next = alloc_and_link_vma(&mm, 0x5000, 0x8000, 5, flags); + vmg.anon_vma = &dummy_anon_vma; + vma_set_dummy_anon_vma(vma, &dummy_anon_vma_chain); + vmg_set_range(&vmg, 0x3000, 0x5000, 3, flags); + vmg.prev = vma_prev; + vmg.middle = vma; + + ASSERT_EQ(merge_existing(&vmg), vma_prev); + ASSERT_EQ(vmg.state, VMA_MERGE_SUCCESS); + + ASSERT_EQ(vma_prev->vm_start, 0); + ASSERT_EQ(vma_prev->vm_end, 0x8000); + + ASSERT_EQ(vma_prev->anon_vma, &dummy_anon_vma); + ASSERT_TRUE(vma_prev->anon_vma->was_cloned); + + cleanup_mm(&mm, &vmi); + + /* + * vma has anon_vma, we assign to prev. + * + * |<----->| + * |-------************* + * prev vma + * extend shrink/delete + */ + + vma_prev = alloc_and_link_vma(&mm, 0, 0x3000, 0, flags); + vma = alloc_and_link_vma(&mm, 0x3000, 0x8000, 3, flags); + + vma_set_dummy_anon_vma(vma, &dummy_anon_vma_chain); + vmg_set_range(&vmg, 0x3000, 0x5000, 3, flags); + vmg.prev = vma_prev; + vmg.middle = vma; + + ASSERT_EQ(merge_existing(&vmg), vma_prev); + ASSERT_EQ(vmg.state, VMA_MERGE_SUCCESS); + + ASSERT_EQ(vma_prev->vm_start, 0); + ASSERT_EQ(vma_prev->vm_end, 0x5000); + + ASSERT_EQ(vma_prev->anon_vma, &dummy_anon_vma); + ASSERT_TRUE(vma_prev->anon_vma->was_cloned); + + cleanup_mm(&mm, &vmi); + + /* + * vma has anon_vma, we assign to next. + * + * |<----->| + * *************-------| + * vma next + * shrink/delete extend + */ + + vma = alloc_and_link_vma(&mm, 0, 0x5000, 0, flags); + vma_next = alloc_and_link_vma(&mm, 0x5000, 0x8000, 5, flags); + + vma_set_dummy_anon_vma(vma, &dummy_anon_vma_chain); + vmg_set_range(&vmg, 0x3000, 0x5000, 3, flags); + vmg.prev = vma; + vmg.middle = vma; + + ASSERT_EQ(merge_existing(&vmg), vma_next); + ASSERT_EQ(vmg.state, VMA_MERGE_SUCCESS); + + ASSERT_EQ(vma_next->vm_start, 0x3000); + ASSERT_EQ(vma_next->vm_end, 0x8000); + + ASSERT_EQ(vma_next->anon_vma, &dummy_anon_vma); + ASSERT_TRUE(vma_next->anon_vma->was_cloned); + + cleanup_mm(&mm, &vmi); + return true; +} + +static bool test_vmi_prealloc_fail(void) +{ + unsigned long flags = VM_READ | VM_WRITE | VM_MAYREAD | VM_MAYWRITE; + struct mm_struct mm = {}; + VMA_ITERATOR(vmi, &mm, 0); + struct vma_merge_struct vmg = { + .mm = &mm, + .vmi = &vmi, + }; + struct anon_vma_chain avc = {}; + struct vm_area_struct *vma_prev, *vma; + + /* + * We are merging vma into prev, with vma possessing an anon_vma, which + * will be duplicated. We cause the vmi preallocation to fail and assert + * the duplicated anon_vma is unlinked. + */ + + vma_prev = alloc_and_link_vma(&mm, 0, 0x3000, 0, flags); + vma = alloc_and_link_vma(&mm, 0x3000, 0x5000, 3, flags); + vma->anon_vma = &dummy_anon_vma; + + vmg_set_range_anon_vma(&vmg, 0x3000, 0x5000, 3, flags, &dummy_anon_vma); + vmg.prev = vma_prev; + vmg.middle = vma; + vma_set_dummy_anon_vma(vma, &avc); + + fail_prealloc = true; + + /* This will cause the merge to fail. */ + ASSERT_EQ(merge_existing(&vmg), NULL); + ASSERT_EQ(vmg.state, VMA_MERGE_ERROR_NOMEM); + /* We will already have assigned the anon_vma. */ + ASSERT_EQ(vma_prev->anon_vma, &dummy_anon_vma); + /* And it was both cloned and unlinked. */ + ASSERT_TRUE(dummy_anon_vma.was_cloned); + ASSERT_TRUE(dummy_anon_vma.was_unlinked); + + cleanup_mm(&mm, &vmi); /* Resets fail_prealloc too. */ + + /* + * We repeat the same operation for expanding a VMA, which is what new + * VMA merging ultimately uses too. This asserts that unlinking is + * performed in this case too. + */ + + vma_prev = alloc_and_link_vma(&mm, 0, 0x3000, 0, flags); + vma = alloc_and_link_vma(&mm, 0x3000, 0x5000, 3, flags); + vma->anon_vma = &dummy_anon_vma; + + vmg_set_range(&vmg, 0, 0x5000, 3, flags); + vmg.middle = vma_prev; + vmg.next = vma; + + fail_prealloc = true; + ASSERT_EQ(expand_existing(&vmg), -ENOMEM); + ASSERT_EQ(vmg.state, VMA_MERGE_ERROR_NOMEM); + + ASSERT_EQ(vma_prev->anon_vma, &dummy_anon_vma); + ASSERT_TRUE(dummy_anon_vma.was_cloned); + ASSERT_TRUE(dummy_anon_vma.was_unlinked); + + cleanup_mm(&mm, &vmi); + return true; +} + +static bool test_merge_extend(void) +{ + unsigned long flags = VM_READ | VM_WRITE | VM_MAYREAD | VM_MAYWRITE; + struct mm_struct mm = {}; + VMA_ITERATOR(vmi, &mm, 0x1000); + struct vm_area_struct *vma; + + vma = alloc_and_link_vma(&mm, 0, 0x1000, 0, flags); + alloc_and_link_vma(&mm, 0x3000, 0x4000, 3, flags); + + /* + * Extend a VMA into the gap between itself and the following VMA. + * This should result in a merge. + * + * <-> + * * * + * + */ + + ASSERT_EQ(vma_merge_extend(&vmi, vma, 0x2000), vma); + ASSERT_EQ(vma->vm_start, 0); + ASSERT_EQ(vma->vm_end, 0x4000); + ASSERT_EQ(vma->vm_pgoff, 0); + ASSERT_TRUE(vma_write_started(vma)); + ASSERT_EQ(mm.map_count, 1); + + cleanup_mm(&mm, &vmi); + return true; +} + +static bool test_copy_vma(void) +{ + unsigned long flags = VM_READ | VM_WRITE | VM_MAYREAD | VM_MAYWRITE; + struct mm_struct mm = {}; + bool need_locks = false; + VMA_ITERATOR(vmi, &mm, 0); + struct vm_area_struct *vma, *vma_new, *vma_next; + + /* Move backwards and do not merge. */ + + vma = alloc_and_link_vma(&mm, 0x3000, 0x5000, 3, flags); + vma_new = copy_vma(&vma, 0, 0x2000, 0, &need_locks); + ASSERT_NE(vma_new, vma); + ASSERT_EQ(vma_new->vm_start, 0); + ASSERT_EQ(vma_new->vm_end, 0x2000); + ASSERT_EQ(vma_new->vm_pgoff, 0); + vma_assert_attached(vma_new); + + cleanup_mm(&mm, &vmi); + + /* Move a VMA into position next to another and merge the two. */ + + vma = alloc_and_link_vma(&mm, 0, 0x2000, 0, flags); + vma_next = alloc_and_link_vma(&mm, 0x6000, 0x8000, 6, flags); + vma_new = copy_vma(&vma, 0x4000, 0x2000, 4, &need_locks); + vma_assert_attached(vma_new); + + ASSERT_EQ(vma_new, vma_next); + + cleanup_mm(&mm, &vmi); + return true; +} + +static bool test_expand_only_mode(void) +{ + unsigned long flags = VM_READ | VM_WRITE | VM_MAYREAD | VM_MAYWRITE; + struct mm_struct mm = {}; + VMA_ITERATOR(vmi, &mm, 0); + struct vm_area_struct *vma_prev, *vma; + VMG_STATE(vmg, &mm, &vmi, 0x5000, 0x9000, flags, 5); + + /* + * Place a VMA prior to the one we're expanding so we assert that we do + * not erroneously try to traverse to the previous VMA even though we + * have, through the use of the just_expand flag, indicated we do not + * need to do so. + */ + alloc_and_link_vma(&mm, 0, 0x2000, 0, flags); + + /* + * We will be positioned at the prev VMA, but looking to expand to + * 0x9000. + */ + vma_iter_set(&vmi, 0x3000); + vma_prev = alloc_and_link_vma(&mm, 0x3000, 0x5000, 3, flags); + vmg.prev = vma_prev; + vmg.just_expand = true; + + vma = vma_merge_new_range(&vmg); + ASSERT_NE(vma, NULL); + ASSERT_EQ(vma, vma_prev); + ASSERT_EQ(vmg.state, VMA_MERGE_SUCCESS); + ASSERT_EQ(vma->vm_start, 0x3000); + ASSERT_EQ(vma->vm_end, 0x9000); + ASSERT_EQ(vma->vm_pgoff, 3); + ASSERT_TRUE(vma_write_started(vma)); + ASSERT_EQ(vma_iter_addr(&vmi), 0x3000); + vma_assert_attached(vma); + + cleanup_mm(&mm, &vmi); + return true; +} + +static bool test_mmap_region_basic(void) +{ + struct mm_struct mm = {}; + unsigned long addr; + struct vm_area_struct *vma; + VMA_ITERATOR(vmi, &mm, 0); + + current->mm = &mm; + + /* Map at 0x300000, length 0x3000. */ + addr = __mmap_region(NULL, 0x300000, 0x3000, + VM_READ | VM_WRITE | VM_MAYREAD | VM_MAYWRITE, + 0x300, NULL); + ASSERT_EQ(addr, 0x300000); + + /* Map at 0x250000, length 0x3000. */ + addr = __mmap_region(NULL, 0x250000, 0x3000, + VM_READ | VM_WRITE | VM_MAYREAD | VM_MAYWRITE, + 0x250, NULL); + ASSERT_EQ(addr, 0x250000); + + /* Map at 0x303000, merging to 0x300000 of length 0x6000. */ + addr = __mmap_region(NULL, 0x303000, 0x3000, + VM_READ | VM_WRITE | VM_MAYREAD | VM_MAYWRITE, + 0x303, NULL); + ASSERT_EQ(addr, 0x303000); + + /* Map at 0x24d000, merging to 0x250000 of length 0x6000. */ + addr = __mmap_region(NULL, 0x24d000, 0x3000, + VM_READ | VM_WRITE | VM_MAYREAD | VM_MAYWRITE, + 0x24d, NULL); + ASSERT_EQ(addr, 0x24d000); + + ASSERT_EQ(mm.map_count, 2); + + for_each_vma(vmi, vma) { + if (vma->vm_start == 0x300000) { + ASSERT_EQ(vma->vm_end, 0x306000); + ASSERT_EQ(vma->vm_pgoff, 0x300); + } else if (vma->vm_start == 0x24d000) { + ASSERT_EQ(vma->vm_end, 0x253000); + ASSERT_EQ(vma->vm_pgoff, 0x24d); + } else { + ASSERT_FALSE(true); + } + } + + cleanup_mm(&mm, &vmi); + return true; +} + +int main(void) +{ + int num_tests = 0, num_fail = 0; + + maple_tree_init(); + vma_state_init(); + +#define TEST(name) \ + do { \ + num_tests++; \ + if (!test_##name()) { \ + num_fail++; \ + fprintf(stderr, "Test " #name " FAILED\n"); \ + } \ + } while (0) + + /* Very simple tests to kick the tyres. */ + TEST(simple_merge); + TEST(simple_modify); + TEST(simple_expand); + TEST(simple_shrink); + + TEST(merge_new); + TEST(vma_merge_special_flags); + TEST(vma_merge_with_close); + TEST(vma_merge_new_with_close); + TEST(merge_existing); + TEST(anon_vma_non_mergeable); + TEST(dup_anon_vma); + TEST(vmi_prealloc_fail); + TEST(merge_extend); + TEST(copy_vma); + TEST(expand_only_mode); + + TEST(mmap_region_basic); + +#undef TEST + + printf("%d tests run, %d passed, %d failed.\n", + num_tests, num_tests - num_fail, num_fail); + + return num_fail == 0 ? EXIT_SUCCESS : EXIT_FAILURE; +} diff --git a/tools/testing/vma/vma_internal.h b/tools/testing/vma/vma_internal.h new file mode 100644 index 000000000000..14718ca23a05 --- /dev/null +++ b/tools/testing/vma/vma_internal.h @@ -0,0 +1,1487 @@ +/* SPDX-License-Identifier: GPL-2.0+ */ +/* + * vma_internal.h + * + * Header providing userland wrappers and shims for the functionality provided + * by mm/vma_internal.h. + * + * We make the header guard the same as mm/vma_internal.h, so if this shim + * header is included, it precludes the inclusion of the kernel one. + */ + +#ifndef __MM_VMA_INTERNAL_H +#define __MM_VMA_INTERNAL_H + +#define __private +#define __bitwise +#define __randomize_layout + +#define CONFIG_MMU +#define CONFIG_PER_VMA_LOCK + +#include <stdlib.h> + +#include <linux/list.h> +#include <linux/maple_tree.h> +#include <linux/mm.h> +#include <linux/rbtree.h> +#include <linux/refcount.h> + +extern unsigned long stack_guard_gap; +#ifdef CONFIG_MMU +extern unsigned long mmap_min_addr; +extern unsigned long dac_mmap_min_addr; +#else +#define mmap_min_addr 0UL +#define dac_mmap_min_addr 0UL +#endif + +#define VM_WARN_ON(_expr) (WARN_ON(_expr)) +#define VM_WARN_ON_ONCE(_expr) (WARN_ON_ONCE(_expr)) +#define VM_WARN_ON_VMG(_expr, _vmg) (WARN_ON(_expr)) +#define VM_BUG_ON(_expr) (BUG_ON(_expr)) +#define VM_BUG_ON_VMA(_expr, _vma) (BUG_ON(_expr)) + +#define MMF_HAS_MDWE 28 + +#define VM_NONE 0x00000000 +#define VM_READ 0x00000001 +#define VM_WRITE 0x00000002 +#define VM_EXEC 0x00000004 +#define VM_SHARED 0x00000008 +#define VM_MAYREAD 0x00000010 +#define VM_MAYWRITE 0x00000020 +#define VM_MAYEXEC 0x00000040 +#define VM_GROWSDOWN 0x00000100 +#define VM_PFNMAP 0x00000400 +#define VM_LOCKED 0x00002000 +#define VM_IO 0x00004000 +#define VM_SEQ_READ 0x00008000 /* App will access data sequentially */ +#define VM_RAND_READ 0x00010000 /* App will not benefit from clustered reads */ +#define VM_DONTEXPAND 0x00040000 +#define VM_LOCKONFAULT 0x00080000 +#define VM_ACCOUNT 0x00100000 +#define VM_NORESERVE 0x00200000 +#define VM_MIXEDMAP 0x10000000 +#define VM_STACK VM_GROWSDOWN +#define VM_SHADOW_STACK VM_NONE +#define VM_SOFTDIRTY 0 +#define VM_ARCH_1 0x01000000 /* Architecture-specific flag */ +#define VM_GROWSUP VM_NONE + +#define VM_ACCESS_FLAGS (VM_READ | VM_WRITE | VM_EXEC) +#define VM_SPECIAL (VM_IO | VM_DONTEXPAND | VM_PFNMAP | VM_MIXEDMAP) + +#ifdef CONFIG_STACK_GROWSUP +#define VM_STACK VM_GROWSUP +#define VM_STACK_EARLY VM_GROWSDOWN +#else +#define VM_STACK VM_GROWSDOWN +#define VM_STACK_EARLY 0 +#endif + +#define DEFAULT_MAP_WINDOW ((1UL << 47) - PAGE_SIZE) +#define TASK_SIZE_LOW DEFAULT_MAP_WINDOW +#define TASK_SIZE_MAX DEFAULT_MAP_WINDOW +#define STACK_TOP TASK_SIZE_LOW +#define STACK_TOP_MAX TASK_SIZE_MAX + +/* This mask represents all the VMA flag bits used by mlock */ +#define VM_LOCKED_MASK (VM_LOCKED | VM_LOCKONFAULT) + +#define TASK_EXEC ((current->personality & READ_IMPLIES_EXEC) ? VM_EXEC : 0) + +#define VM_DATA_FLAGS_TSK_EXEC (VM_READ | VM_WRITE | TASK_EXEC | \ + VM_MAYREAD | VM_MAYWRITE | VM_MAYEXEC) + +#define VM_DATA_DEFAULT_FLAGS VM_DATA_FLAGS_TSK_EXEC + +#define VM_STARTGAP_FLAGS (VM_GROWSDOWN | VM_SHADOW_STACK) + +#define VM_STACK_DEFAULT_FLAGS VM_DATA_DEFAULT_FLAGS +#define VM_STACK_FLAGS (VM_STACK | VM_STACK_DEFAULT_FLAGS | VM_ACCOUNT) +#define VM_STACK_INCOMPLETE_SETUP (VM_RAND_READ | VM_SEQ_READ | VM_STACK_EARLY) + +#define RLIMIT_STACK 3 /* max stack size */ +#define RLIMIT_MEMLOCK 8 /* max locked-in-memory address space */ + +#define CAP_IPC_LOCK 14 + +#ifdef CONFIG_64BIT +/* VM is sealed, in vm_flags */ +#define VM_SEALED _BITUL(63) +#endif + +#define FIRST_USER_ADDRESS 0UL +#define USER_PGTABLES_CEILING 0UL + +#define vma_policy(vma) NULL + +#define down_write_nest_lock(sem, nest_lock) + +#define pgprot_val(x) ((x).pgprot) +#define __pgprot(x) ((pgprot_t) { (x) } ) + +#define for_each_vma(__vmi, __vma) \ + while (((__vma) = vma_next(&(__vmi))) != NULL) + +/* The MM code likes to work with exclusive end addresses */ +#define for_each_vma_range(__vmi, __vma, __end) \ + while (((__vma) = vma_find(&(__vmi), (__end))) != NULL) + +#define offset_in_page(p) ((unsigned long)(p) & ~PAGE_MASK) + +#define PHYS_PFN(x) ((unsigned long)((x) >> PAGE_SHIFT)) + +#define test_and_set_bit(nr, addr) __test_and_set_bit(nr, addr) +#define test_and_clear_bit(nr, addr) __test_and_clear_bit(nr, addr) + +#define TASK_SIZE ((1ul << 47)-PAGE_SIZE) + +#define AS_MM_ALL_LOCKS 2 + +/* We hardcode this for now. */ +#define sysctl_max_map_count 0x1000000UL + +#define pgoff_t unsigned long +typedef unsigned long pgprotval_t; +typedef struct pgprot { pgprotval_t pgprot; } pgprot_t; +typedef unsigned long vm_flags_t; +typedef __bitwise unsigned int vm_fault_t; + +/* + * The shared stubs do not implement this, it amounts to an fprintf(STDERR,...) + * either way :) + */ +#define pr_warn_once pr_err + +#define data_race(expr) expr + +#define ASSERT_EXCLUSIVE_WRITER(x) + +/** + * swap - swap values of @a and @b + * @a: first value + * @b: second value + */ +#define swap(a, b) \ + do { typeof(a) __tmp = (a); (a) = (b); (b) = __tmp; } while (0) + +struct kref { + refcount_t refcount; +}; + +/* + * Define the task command name length as enum, then it can be visible to + * BPF programs. + */ +enum { + TASK_COMM_LEN = 16, +}; + +/* + * Flags for bug emulation. + * + * These occupy the top three bytes. + */ +enum { + READ_IMPLIES_EXEC = 0x0400000, +}; + +struct task_struct { + char comm[TASK_COMM_LEN]; + pid_t pid; + struct mm_struct *mm; + + /* Used for emulating ABI behavior of previous Linux versions: */ + unsigned int personality; +}; + +struct task_struct *get_current(void); +#define current get_current() + +struct anon_vma { + struct anon_vma *root; + struct rb_root_cached rb_root; + + /* Test fields. */ + bool was_cloned; + bool was_unlinked; +}; + +struct anon_vma_chain { + struct anon_vma *anon_vma; + struct list_head same_vma; +}; + +struct anon_vma_name { + struct kref kref; + /* The name needs to be at the end because it is dynamically sized. */ + char name[]; +}; + +struct vma_iterator { + struct ma_state mas; +}; + +#define VMA_ITERATOR(name, __mm, __addr) \ + struct vma_iterator name = { \ + .mas = { \ + .tree = &(__mm)->mm_mt, \ + .index = __addr, \ + .node = NULL, \ + .status = ma_start, \ + }, \ + } + +struct address_space { + struct rb_root_cached i_mmap; + unsigned long flags; + atomic_t i_mmap_writable; +}; + +struct vm_userfaultfd_ctx {}; +struct mempolicy {}; +struct mmu_gather {}; +struct mutex {}; +#define DEFINE_MUTEX(mutexname) \ + struct mutex mutexname = {} + +struct mm_struct { + struct maple_tree mm_mt; + int map_count; /* number of VMAs */ + unsigned long total_vm; /* Total pages mapped */ + unsigned long locked_vm; /* Pages that have PG_mlocked set */ + unsigned long data_vm; /* VM_WRITE & ~VM_SHARED & ~VM_STACK */ + unsigned long exec_vm; /* VM_EXEC & ~VM_WRITE & ~VM_STACK */ + unsigned long stack_vm; /* VM_STACK */ + + unsigned long def_flags; + + unsigned long flags; /* Must use atomic bitops to access */ +}; + +struct vm_area_struct; + +/* + * Describes a VMA that is about to be mmap()'ed. Drivers may choose to + * manipulate mutable fields which will cause those fields to be updated in the + * resultant VMA. + * + * Helper functions are not required for manipulating any field. + */ +struct vm_area_desc { + /* Immutable state. */ + struct mm_struct *mm; + unsigned long start; + unsigned long end; + + /* Mutable fields. Populated with initial state. */ + pgoff_t pgoff; + struct file *file; + vm_flags_t vm_flags; + pgprot_t page_prot; + + /* Write-only fields. */ + const struct vm_operations_struct *vm_ops; + void *private_data; +}; + +struct file_operations { + int (*mmap)(struct file *, struct vm_area_struct *); + int (*mmap_prepare)(struct vm_area_desc *); +}; + +struct file { + struct address_space *f_mapping; + const struct file_operations *f_op; +}; + +#define VMA_LOCK_OFFSET 0x40000000 + +typedef struct { unsigned long v; } freeptr_t; + +struct vm_area_struct { + /* The first cache line has the info for VMA tree walking. */ + + union { + struct { + /* VMA covers [vm_start; vm_end) addresses within mm */ + unsigned long vm_start; + unsigned long vm_end; + }; + freeptr_t vm_freeptr; /* Pointer used by SLAB_TYPESAFE_BY_RCU */ + }; + + struct mm_struct *vm_mm; /* The address space we belong to. */ + pgprot_t vm_page_prot; /* Access permissions of this VMA. */ + + /* + * Flags, see mm.h. + * To modify use vm_flags_{init|reset|set|clear|mod} functions. + */ + union { + const vm_flags_t vm_flags; + vm_flags_t __private __vm_flags; + }; + +#ifdef CONFIG_PER_VMA_LOCK + /* + * Can only be written (using WRITE_ONCE()) while holding both: + * - mmap_lock (in write mode) + * - vm_refcnt bit at VMA_LOCK_OFFSET is set + * Can be read reliably while holding one of: + * - mmap_lock (in read or write mode) + * - vm_refcnt bit at VMA_LOCK_OFFSET is set or vm_refcnt > 1 + * Can be read unreliably (using READ_ONCE()) for pessimistic bailout + * while holding nothing (except RCU to keep the VMA struct allocated). + * + * This sequence counter is explicitly allowed to overflow; sequence + * counter reuse can only lead to occasional unnecessary use of the + * slowpath. + */ + unsigned int vm_lock_seq; +#endif + + /* + * A file's MAP_PRIVATE vma can be in both i_mmap tree and anon_vma + * list, after a COW of one of the file pages. A MAP_SHARED vma + * can only be in the i_mmap tree. An anonymous MAP_PRIVATE, stack + * or brk vma (with NULL file) can only be in an anon_vma list. + */ + struct list_head anon_vma_chain; /* Serialized by mmap_lock & + * page_table_lock */ + struct anon_vma *anon_vma; /* Serialized by page_table_lock */ + + /* Function pointers to deal with this struct. */ + const struct vm_operations_struct *vm_ops; + + /* Information about our backing store: */ + unsigned long vm_pgoff; /* Offset (within vm_file) in PAGE_SIZE + units */ + struct file * vm_file; /* File we map to (can be NULL). */ + void * vm_private_data; /* was vm_pte (shared mem) */ + +#ifdef CONFIG_SWAP + atomic_long_t swap_readahead_info; +#endif +#ifndef CONFIG_MMU + struct vm_region *vm_region; /* NOMMU mapping region */ +#endif +#ifdef CONFIG_NUMA + struct mempolicy *vm_policy; /* NUMA policy for the VMA */ +#endif +#ifdef CONFIG_NUMA_BALANCING + struct vma_numab_state *numab_state; /* NUMA Balancing state */ +#endif +#ifdef CONFIG_PER_VMA_LOCK + /* Unstable RCU readers are allowed to read this. */ + refcount_t vm_refcnt; +#endif + /* + * For areas with an address space and backing store, + * linkage into the address_space->i_mmap interval tree. + * + */ + struct { + struct rb_node rb; + unsigned long rb_subtree_last; + } shared; +#ifdef CONFIG_ANON_VMA_NAME + /* + * For private and shared anonymous mappings, a pointer to a null + * terminated string containing the name given to the vma, or NULL if + * unnamed. Serialized by mmap_lock. Use anon_vma_name to access. + */ + struct anon_vma_name *anon_name; +#endif + struct vm_userfaultfd_ctx vm_userfaultfd_ctx; +} __randomize_layout; + +struct vm_fault {}; + +struct vm_operations_struct { + void (*open)(struct vm_area_struct * area); + /** + * @close: Called when the VMA is being removed from the MM. + * Context: User context. May sleep. Caller holds mmap_lock. + */ + void (*close)(struct vm_area_struct * area); + /* Called any time before splitting to check if it's allowed */ + int (*may_split)(struct vm_area_struct *area, unsigned long addr); + int (*mremap)(struct vm_area_struct *area); + /* + * Called by mprotect() to make driver-specific permission + * checks before mprotect() is finalised. The VMA must not + * be modified. Returns 0 if mprotect() can proceed. + */ + int (*mprotect)(struct vm_area_struct *vma, unsigned long start, + unsigned long end, unsigned long newflags); + vm_fault_t (*fault)(struct vm_fault *vmf); + vm_fault_t (*huge_fault)(struct vm_fault *vmf, unsigned int order); + vm_fault_t (*map_pages)(struct vm_fault *vmf, + pgoff_t start_pgoff, pgoff_t end_pgoff); + unsigned long (*pagesize)(struct vm_area_struct * area); + + /* notification that a previously read-only page is about to become + * writable, if an error is returned it will cause a SIGBUS */ + vm_fault_t (*page_mkwrite)(struct vm_fault *vmf); + + /* same as page_mkwrite when using VM_PFNMAP|VM_MIXEDMAP */ + vm_fault_t (*pfn_mkwrite)(struct vm_fault *vmf); + + /* called by access_process_vm when get_user_pages() fails, typically + * for use by special VMAs. See also generic_access_phys() for a generic + * implementation useful for any iomem mapping. + */ + int (*access)(struct vm_area_struct *vma, unsigned long addr, + void *buf, int len, int write); + + /* Called by the /proc/PID/maps code to ask the vma whether it + * has a special name. Returning non-NULL will also cause this + * vma to be dumped unconditionally. */ + const char *(*name)(struct vm_area_struct *vma); + +#ifdef CONFIG_NUMA + /* + * set_policy() op must add a reference to any non-NULL @new mempolicy + * to hold the policy upon return. Caller should pass NULL @new to + * remove a policy and fall back to surrounding context--i.e. do not + * install a MPOL_DEFAULT policy, nor the task or system default + * mempolicy. + */ + int (*set_policy)(struct vm_area_struct *vma, struct mempolicy *new); + + /* + * get_policy() op must add reference [mpol_get()] to any policy at + * (vma,addr) marked as MPOL_SHARED. The shared policy infrastructure + * in mm/mempolicy.c will do this automatically. + * get_policy() must NOT add a ref if the policy at (vma,addr) is not + * marked as MPOL_SHARED. vma policies are protected by the mmap_lock. + * If no [shared/vma] mempolicy exists at the addr, get_policy() op + * must return NULL--i.e., do not "fallback" to task or system default + * policy. + */ + struct mempolicy *(*get_policy)(struct vm_area_struct *vma, + unsigned long addr, pgoff_t *ilx); +#endif + /* + * Called by vm_normal_page() for special PTEs to find the + * page for @addr. This is useful if the default behavior + * (using pte_page()) would not find the correct page. + */ + struct page *(*find_special_page)(struct vm_area_struct *vma, + unsigned long addr); +}; + +struct vm_unmapped_area_info { +#define VM_UNMAPPED_AREA_TOPDOWN 1 + unsigned long flags; + unsigned long length; + unsigned long low_limit; + unsigned long high_limit; + unsigned long align_mask; + unsigned long align_offset; + unsigned long start_gap; +}; + +struct pagetable_move_control { + struct vm_area_struct *old; /* Source VMA. */ + struct vm_area_struct *new; /* Destination VMA. */ + unsigned long old_addr; /* Address from which the move begins. */ + unsigned long old_end; /* Exclusive address at which old range ends. */ + unsigned long new_addr; /* Address to move page tables to. */ + unsigned long len_in; /* Bytes to remap specified by user. */ + + bool need_rmap_locks; /* Do rmap locks need to be taken? */ + bool for_stack; /* Is this an early temp stack being moved? */ +}; + +#define PAGETABLE_MOVE(name, old_, new_, old_addr_, new_addr_, len_) \ + struct pagetable_move_control name = { \ + .old = old_, \ + .new = new_, \ + .old_addr = old_addr_, \ + .old_end = (old_addr_) + (len_), \ + .new_addr = new_addr_, \ + .len_in = len_, \ + } + +struct kmem_cache_args { + /** + * @align: The required alignment for the objects. + * + * %0 means no specific alignment is requested. + */ + unsigned int align; + /** + * @useroffset: Usercopy region offset. + * + * %0 is a valid offset, when @usersize is non-%0 + */ + unsigned int useroffset; + /** + * @usersize: Usercopy region size. + * + * %0 means no usercopy region is specified. + */ + unsigned int usersize; + /** + * @freeptr_offset: Custom offset for the free pointer + * in &SLAB_TYPESAFE_BY_RCU caches + * + * By default &SLAB_TYPESAFE_BY_RCU caches place the free pointer + * outside of the object. This might cause the object to grow in size. + * Cache creators that have a reason to avoid this can specify a custom + * free pointer offset in their struct where the free pointer will be + * placed. + * + * Note that placing the free pointer inside the object requires the + * caller to ensure that no fields are invalidated that are required to + * guard against object recycling (See &SLAB_TYPESAFE_BY_RCU for + * details). + * + * Using %0 as a value for @freeptr_offset is valid. If @freeptr_offset + * is specified, %use_freeptr_offset must be set %true. + * + * Note that @ctor currently isn't supported with custom free pointers + * as a @ctor requires an external free pointer. + */ + unsigned int freeptr_offset; + /** + * @use_freeptr_offset: Whether a @freeptr_offset is used. + */ + bool use_freeptr_offset; + /** + * @ctor: A constructor for the objects. + * + * The constructor is invoked for each object in a newly allocated slab + * page. It is the cache user's responsibility to free object in the + * same state as after calling the constructor, or deal appropriately + * with any differences between a freshly constructed and a reallocated + * object. + * + * %NULL means no constructor. + */ + void (*ctor)(void *); +}; + +static inline void vma_iter_invalidate(struct vma_iterator *vmi) +{ + mas_pause(&vmi->mas); +} + +static inline pgprot_t pgprot_modify(pgprot_t oldprot, pgprot_t newprot) +{ + return __pgprot(pgprot_val(oldprot) | pgprot_val(newprot)); +} + +static inline pgprot_t vm_get_page_prot(unsigned long vm_flags) +{ + return __pgprot(vm_flags); +} + +static inline bool is_shared_maywrite(vm_flags_t vm_flags) +{ + return (vm_flags & (VM_SHARED | VM_MAYWRITE)) == + (VM_SHARED | VM_MAYWRITE); +} + +static inline bool vma_is_shared_maywrite(struct vm_area_struct *vma) +{ + return is_shared_maywrite(vma->vm_flags); +} + +static inline struct vm_area_struct *vma_next(struct vma_iterator *vmi) +{ + /* + * Uses mas_find() to get the first VMA when the iterator starts. + * Calling mas_next() could skip the first entry. + */ + return mas_find(&vmi->mas, ULONG_MAX); +} + +/* + * WARNING: to avoid racing with vma_mark_attached()/vma_mark_detached(), these + * assertions should be made either under mmap_write_lock or when the object + * has been isolated under mmap_write_lock, ensuring no competing writers. + */ +static inline void vma_assert_attached(struct vm_area_struct *vma) +{ + WARN_ON_ONCE(!refcount_read(&vma->vm_refcnt)); +} + +static inline void vma_assert_detached(struct vm_area_struct *vma) +{ + WARN_ON_ONCE(refcount_read(&vma->vm_refcnt)); +} + +static inline void vma_assert_write_locked(struct vm_area_struct *); +static inline void vma_mark_attached(struct vm_area_struct *vma) +{ + vma_assert_write_locked(vma); + vma_assert_detached(vma); + refcount_set_release(&vma->vm_refcnt, 1); +} + +static inline void vma_mark_detached(struct vm_area_struct *vma) +{ + vma_assert_write_locked(vma); + vma_assert_attached(vma); + /* We are the only writer, so no need to use vma_refcount_put(). */ + if (unlikely(!refcount_dec_and_test(&vma->vm_refcnt))) { + /* + * Reader must have temporarily raised vm_refcnt but it will + * drop it without using the vma since vma is write-locked. + */ + } +} + +extern const struct vm_operations_struct vma_dummy_vm_ops; + +extern unsigned long rlimit(unsigned int limit); + +static inline void vma_init(struct vm_area_struct *vma, struct mm_struct *mm) +{ + memset(vma, 0, sizeof(*vma)); + vma->vm_mm = mm; + vma->vm_ops = &vma_dummy_vm_ops; + INIT_LIST_HEAD(&vma->anon_vma_chain); + vma->vm_lock_seq = UINT_MAX; +} + +struct kmem_cache { + const char *name; + size_t object_size; + struct kmem_cache_args *args; +}; + +static inline struct kmem_cache *__kmem_cache_create(const char *name, + size_t object_size, + struct kmem_cache_args *args) +{ + struct kmem_cache *ret = malloc(sizeof(struct kmem_cache)); + + ret->name = name; + ret->object_size = object_size; + ret->args = args; + + return ret; +} + +#define kmem_cache_create(__name, __object_size, __args, ...) \ + __kmem_cache_create((__name), (__object_size), (__args)) + +static inline void *kmem_cache_alloc(struct kmem_cache *s, gfp_t gfpflags) +{ + (void)gfpflags; + + return calloc(s->object_size, 1); +} + +static inline void kmem_cache_free(struct kmem_cache *s, void *x) +{ + free(x); +} + +/* + * These are defined in vma.h, but sadly vm_stat_account() is referenced by + * kernel/fork.c, so we have to these broadly available there, and temporarily + * define them here to resolve the dependency cycle. + */ + +#define is_exec_mapping(flags) \ + ((flags & (VM_EXEC | VM_WRITE | VM_STACK)) == VM_EXEC) + +#define is_stack_mapping(flags) \ + (((flags & VM_STACK) == VM_STACK) || (flags & VM_SHADOW_STACK)) + +#define is_data_mapping(flags) \ + ((flags & (VM_WRITE | VM_SHARED | VM_STACK)) == VM_WRITE) + +static inline void vm_stat_account(struct mm_struct *mm, vm_flags_t flags, + long npages) +{ + WRITE_ONCE(mm->total_vm, READ_ONCE(mm->total_vm)+npages); + + if (is_exec_mapping(flags)) + mm->exec_vm += npages; + else if (is_stack_mapping(flags)) + mm->stack_vm += npages; + else if (is_data_mapping(flags)) + mm->data_vm += npages; +} + +#undef is_exec_mapping +#undef is_stack_mapping +#undef is_data_mapping + +/* Currently stubbed but we may later wish to un-stub. */ +static inline void vm_acct_memory(long pages); +static inline void vm_unacct_memory(long pages) +{ + vm_acct_memory(-pages); +} + +static inline void mapping_allow_writable(struct address_space *mapping) +{ + atomic_inc(&mapping->i_mmap_writable); +} + +static inline void vma_set_range(struct vm_area_struct *vma, + unsigned long start, unsigned long end, + pgoff_t pgoff) +{ + vma->vm_start = start; + vma->vm_end = end; + vma->vm_pgoff = pgoff; +} + +static inline +struct vm_area_struct *vma_find(struct vma_iterator *vmi, unsigned long max) +{ + return mas_find(&vmi->mas, max - 1); +} + +static inline int vma_iter_clear_gfp(struct vma_iterator *vmi, + unsigned long start, unsigned long end, gfp_t gfp) +{ + __mas_set_range(&vmi->mas, start, end - 1); + mas_store_gfp(&vmi->mas, NULL, gfp); + if (unlikely(mas_is_err(&vmi->mas))) + return -ENOMEM; + + return 0; +} + +static inline void mmap_assert_locked(struct mm_struct *); +static inline struct vm_area_struct *find_vma_intersection(struct mm_struct *mm, + unsigned long start_addr, + unsigned long end_addr) +{ + unsigned long index = start_addr; + + mmap_assert_locked(mm); + return mt_find(&mm->mm_mt, &index, end_addr - 1); +} + +static inline +struct vm_area_struct *vma_lookup(struct mm_struct *mm, unsigned long addr) +{ + return mtree_load(&mm->mm_mt, addr); +} + +static inline struct vm_area_struct *vma_prev(struct vma_iterator *vmi) +{ + return mas_prev(&vmi->mas, 0); +} + +static inline void vma_iter_set(struct vma_iterator *vmi, unsigned long addr) +{ + mas_set(&vmi->mas, addr); +} + +static inline bool vma_is_anonymous(struct vm_area_struct *vma) +{ + return !vma->vm_ops; +} + +/* Defined in vma.h, so temporarily define here to avoid circular dependency. */ +#define vma_iter_load(vmi) \ + mas_walk(&(vmi)->mas) + +static inline struct vm_area_struct * +find_vma_prev(struct mm_struct *mm, unsigned long addr, + struct vm_area_struct **pprev) +{ + struct vm_area_struct *vma; + VMA_ITERATOR(vmi, mm, addr); + + vma = vma_iter_load(&vmi); + *pprev = vma_prev(&vmi); + if (!vma) + vma = vma_next(&vmi); + return vma; +} + +#undef vma_iter_load + +static inline void vma_iter_init(struct vma_iterator *vmi, + struct mm_struct *mm, unsigned long addr) +{ + mas_init(&vmi->mas, &mm->mm_mt, addr); +} + +/* Stubbed functions. */ + +static inline struct anon_vma_name *anon_vma_name(struct vm_area_struct *vma) +{ + return NULL; +} + +static inline bool is_mergeable_vm_userfaultfd_ctx(struct vm_area_struct *vma, + struct vm_userfaultfd_ctx vm_ctx) +{ + return true; +} + +static inline bool anon_vma_name_eq(struct anon_vma_name *anon_name1, + struct anon_vma_name *anon_name2) +{ + return true; +} + +static inline void might_sleep(void) +{ +} + +static inline unsigned long vma_pages(struct vm_area_struct *vma) +{ + return (vma->vm_end - vma->vm_start) >> PAGE_SHIFT; +} + +static inline void fput(struct file *) +{ +} + +static inline void mpol_put(struct mempolicy *) +{ +} + +static inline void lru_add_drain(void) +{ +} + +static inline void tlb_gather_mmu(struct mmu_gather *, struct mm_struct *) +{ +} + +static inline void update_hiwater_rss(struct mm_struct *) +{ +} + +static inline void update_hiwater_vm(struct mm_struct *) +{ +} + +static inline void unmap_vmas(struct mmu_gather *tlb, struct ma_state *mas, + struct vm_area_struct *vma, unsigned long start_addr, + unsigned long end_addr, unsigned long tree_end, + bool mm_wr_locked) +{ + (void)tlb; + (void)mas; + (void)vma; + (void)start_addr; + (void)end_addr; + (void)tree_end; + (void)mm_wr_locked; +} + +static inline void free_pgtables(struct mmu_gather *tlb, struct ma_state *mas, + struct vm_area_struct *vma, unsigned long floor, + unsigned long ceiling, bool mm_wr_locked) +{ + (void)tlb; + (void)mas; + (void)vma; + (void)floor; + (void)ceiling; + (void)mm_wr_locked; +} + +static inline void mapping_unmap_writable(struct address_space *) +{ +} + +static inline void flush_dcache_mmap_lock(struct address_space *) +{ +} + +static inline void tlb_finish_mmu(struct mmu_gather *) +{ +} + +static inline struct file *get_file(struct file *f) +{ + return f; +} + +static inline int vma_dup_policy(struct vm_area_struct *, struct vm_area_struct *) +{ + return 0; +} + +static inline int anon_vma_clone(struct vm_area_struct *dst, struct vm_area_struct *src) +{ + /* For testing purposes. We indicate that an anon_vma has been cloned. */ + if (src->anon_vma != NULL) { + dst->anon_vma = src->anon_vma; + dst->anon_vma->was_cloned = true; + } + + return 0; +} + +static inline void vma_start_write(struct vm_area_struct *vma) +{ + /* Used to indicate to tests that a write operation has begun. */ + vma->vm_lock_seq++; +} + +static inline void vma_adjust_trans_huge(struct vm_area_struct *vma, + unsigned long start, + unsigned long end, + struct vm_area_struct *next) +{ + (void)vma; + (void)start; + (void)end; + (void)next; +} + +static inline void hugetlb_split(struct vm_area_struct *, unsigned long) {} + +static inline void vma_iter_free(struct vma_iterator *vmi) +{ + mas_destroy(&vmi->mas); +} + +static inline +struct vm_area_struct *vma_iter_next_range(struct vma_iterator *vmi) +{ + return mas_next_range(&vmi->mas, ULONG_MAX); +} + +static inline void vm_acct_memory(long pages) +{ +} + +static inline void vma_interval_tree_insert(struct vm_area_struct *, + struct rb_root_cached *) +{ +} + +static inline void vma_interval_tree_remove(struct vm_area_struct *, + struct rb_root_cached *) +{ +} + +static inline void flush_dcache_mmap_unlock(struct address_space *) +{ +} + +static inline void anon_vma_interval_tree_insert(struct anon_vma_chain*, + struct rb_root_cached *) +{ +} + +static inline void anon_vma_interval_tree_remove(struct anon_vma_chain*, + struct rb_root_cached *) +{ +} + +static inline void uprobe_mmap(struct vm_area_struct *) +{ +} + +static inline void uprobe_munmap(struct vm_area_struct *vma, + unsigned long start, unsigned long end) +{ + (void)vma; + (void)start; + (void)end; +} + +static inline void i_mmap_lock_write(struct address_space *) +{ +} + +static inline void anon_vma_lock_write(struct anon_vma *) +{ +} + +static inline void vma_assert_write_locked(struct vm_area_struct *) +{ +} + +static inline void unlink_anon_vmas(struct vm_area_struct *vma) +{ + /* For testing purposes, indicate that the anon_vma was unlinked. */ + vma->anon_vma->was_unlinked = true; +} + +static inline void anon_vma_unlock_write(struct anon_vma *) +{ +} + +static inline void i_mmap_unlock_write(struct address_space *) +{ +} + +static inline void anon_vma_merge(struct vm_area_struct *, + struct vm_area_struct *) +{ +} + +static inline int userfaultfd_unmap_prep(struct vm_area_struct *vma, + unsigned long start, + unsigned long end, + struct list_head *unmaps) +{ + (void)vma; + (void)start; + (void)end; + (void)unmaps; + + return 0; +} + +static inline void mmap_write_downgrade(struct mm_struct *) +{ +} + +static inline void mmap_read_unlock(struct mm_struct *) +{ +} + +static inline void mmap_write_unlock(struct mm_struct *) +{ +} + +static inline int mmap_write_lock_killable(struct mm_struct *) +{ + return 0; +} + +static inline bool can_modify_mm(struct mm_struct *mm, + unsigned long start, + unsigned long end) +{ + (void)mm; + (void)start; + (void)end; + + return true; +} + +static inline void arch_unmap(struct mm_struct *mm, + unsigned long start, + unsigned long end) +{ + (void)mm; + (void)start; + (void)end; +} + +static inline void mmap_assert_locked(struct mm_struct *) +{ +} + +static inline bool mpol_equal(struct mempolicy *, struct mempolicy *) +{ + return true; +} + +static inline void khugepaged_enter_vma(struct vm_area_struct *vma, + unsigned long vm_flags) +{ + (void)vma; + (void)vm_flags; +} + +static inline bool mapping_can_writeback(struct address_space *) +{ + return true; +} + +static inline bool is_vm_hugetlb_page(struct vm_area_struct *) +{ + return false; +} + +static inline bool vma_soft_dirty_enabled(struct vm_area_struct *) +{ + return false; +} + +static inline bool userfaultfd_wp(struct vm_area_struct *) +{ + return false; +} + +static inline void mmap_assert_write_locked(struct mm_struct *) +{ +} + +static inline void mutex_lock(struct mutex *) +{ +} + +static inline void mutex_unlock(struct mutex *) +{ +} + +static inline bool mutex_is_locked(struct mutex *) +{ + return true; +} + +static inline bool signal_pending(void *) +{ + return false; +} + +static inline bool is_file_hugepages(struct file *) +{ + return false; +} + +static inline int security_vm_enough_memory_mm(struct mm_struct *, long) +{ + return 0; +} + +static inline bool may_expand_vm(struct mm_struct *, vm_flags_t, unsigned long) +{ + return true; +} + +static inline void vm_flags_init(struct vm_area_struct *vma, + vm_flags_t flags) +{ + vma->__vm_flags = flags; +} + +static inline void vm_flags_set(struct vm_area_struct *vma, + vm_flags_t flags) +{ + vma_start_write(vma); + vma->__vm_flags |= flags; +} + +static inline void vm_flags_clear(struct vm_area_struct *vma, + vm_flags_t flags) +{ + vma_start_write(vma); + vma->__vm_flags &= ~flags; +} + +static inline int shmem_zero_setup(struct vm_area_struct *) +{ + return 0; +} + +static inline void vma_set_anonymous(struct vm_area_struct *vma) +{ + vma->vm_ops = NULL; +} + +static inline void ksm_add_vma(struct vm_area_struct *) +{ +} + +static inline void perf_event_mmap(struct vm_area_struct *) +{ +} + +static inline bool vma_is_dax(struct vm_area_struct *) +{ + return false; +} + +static inline struct vm_area_struct *get_gate_vma(struct mm_struct *) +{ + return NULL; +} + +bool vma_wants_writenotify(struct vm_area_struct *vma, pgprot_t vm_page_prot); + +/* Update vma->vm_page_prot to reflect vma->vm_flags. */ +static inline void vma_set_page_prot(struct vm_area_struct *vma) +{ + unsigned long vm_flags = vma->vm_flags; + pgprot_t vm_page_prot; + + /* testing: we inline vm_pgprot_modify() to avoid clash with vma.h. */ + vm_page_prot = pgprot_modify(vma->vm_page_prot, vm_get_page_prot(vm_flags)); + + if (vma_wants_writenotify(vma, vm_page_prot)) { + vm_flags &= ~VM_SHARED; + /* testing: we inline vm_pgprot_modify() to avoid clash with vma.h. */ + vm_page_prot = pgprot_modify(vm_page_prot, vm_get_page_prot(vm_flags)); + } + /* remove_protection_ptes reads vma->vm_page_prot without mmap_lock */ + WRITE_ONCE(vma->vm_page_prot, vm_page_prot); +} + +static inline bool arch_validate_flags(unsigned long) +{ + return true; +} + +static inline void vma_close(struct vm_area_struct *) +{ +} + +static inline int mmap_file(struct file *, struct vm_area_struct *) +{ + return 0; +} + +static inline unsigned long stack_guard_start_gap(struct vm_area_struct *vma) +{ + if (vma->vm_flags & VM_GROWSDOWN) + return stack_guard_gap; + + /* See reasoning around the VM_SHADOW_STACK definition */ + if (vma->vm_flags & VM_SHADOW_STACK) + return PAGE_SIZE; + + return 0; +} + +static inline unsigned long vm_start_gap(struct vm_area_struct *vma) +{ + unsigned long gap = stack_guard_start_gap(vma); + unsigned long vm_start = vma->vm_start; + + vm_start -= gap; + if (vm_start > vma->vm_start) + vm_start = 0; + return vm_start; +} + +static inline unsigned long vm_end_gap(struct vm_area_struct *vma) +{ + unsigned long vm_end = vma->vm_end; + + if (vma->vm_flags & VM_GROWSUP) { + vm_end += stack_guard_gap; + if (vm_end < vma->vm_end) + vm_end = -PAGE_SIZE; + } + return vm_end; +} + +static inline int is_hugepage_only_range(struct mm_struct *mm, + unsigned long addr, unsigned long len) +{ + return 0; +} + +static inline bool vma_is_accessible(struct vm_area_struct *vma) +{ + return vma->vm_flags & VM_ACCESS_FLAGS; +} + +static inline bool capable(int cap) +{ + return true; +} + +static inline bool mlock_future_ok(struct mm_struct *mm, unsigned long flags, + unsigned long bytes) +{ + unsigned long locked_pages, limit_pages; + + if (!(flags & VM_LOCKED) || capable(CAP_IPC_LOCK)) + return true; + + locked_pages = bytes >> PAGE_SHIFT; + locked_pages += mm->locked_vm; + + limit_pages = rlimit(RLIMIT_MEMLOCK); + limit_pages >>= PAGE_SHIFT; + + return locked_pages <= limit_pages; +} + +static inline int __anon_vma_prepare(struct vm_area_struct *vma) +{ + struct anon_vma *anon_vma = calloc(1, sizeof(struct anon_vma)); + + if (!anon_vma) + return -ENOMEM; + + anon_vma->root = anon_vma; + vma->anon_vma = anon_vma; + + return 0; +} + +static inline int anon_vma_prepare(struct vm_area_struct *vma) +{ + if (likely(vma->anon_vma)) + return 0; + + return __anon_vma_prepare(vma); +} + +static inline void userfaultfd_unmap_complete(struct mm_struct *mm, + struct list_head *uf) +{ +} + +/* + * Denies creating a writable executable mapping or gaining executable permissions. + * + * This denies the following: + * + * a) mmap(PROT_WRITE | PROT_EXEC) + * + * b) mmap(PROT_WRITE) + * mprotect(PROT_EXEC) + * + * c) mmap(PROT_WRITE) + * mprotect(PROT_READ) + * mprotect(PROT_EXEC) + * + * But allows the following: + * + * d) mmap(PROT_READ | PROT_EXEC) + * mmap(PROT_READ | PROT_EXEC | PROT_BTI) + * + * This is only applicable if the user has set the Memory-Deny-Write-Execute + * (MDWE) protection mask for the current process. + * + * @old specifies the VMA flags the VMA originally possessed, and @new the ones + * we propose to set. + * + * Return: false if proposed change is OK, true if not ok and should be denied. + */ +static inline bool map_deny_write_exec(unsigned long old, unsigned long new) +{ + /* If MDWE is disabled, we have nothing to deny. */ + if (!test_bit(MMF_HAS_MDWE, ¤t->mm->flags)) + return false; + + /* If the new VMA is not executable, we have nothing to deny. */ + if (!(new & VM_EXEC)) + return false; + + /* Under MDWE we do not accept newly writably executable VMAs... */ + if (new & VM_WRITE) + return true; + + /* ...nor previously non-executable VMAs becoming executable. */ + if (!(old & VM_EXEC)) + return true; + + return false; +} + +static inline int mapping_map_writable(struct address_space *mapping) +{ + int c = atomic_read(&mapping->i_mmap_writable); + + /* Derived from the raw_atomic_inc_unless_negative() implementation. */ + do { + if (c < 0) + return -EPERM; + } while (!__sync_bool_compare_and_swap(&mapping->i_mmap_writable, c, c+1)); + + return 0; +} + +static inline unsigned long move_page_tables(struct pagetable_move_control *pmc) +{ + (void)pmc; + + return 0; +} + +static inline void free_pgd_range(struct mmu_gather *tlb, + unsigned long addr, unsigned long end, + unsigned long floor, unsigned long ceiling) +{ + (void)tlb; + (void)addr; + (void)end; + (void)floor; + (void)ceiling; +} + +static inline int ksm_execve(struct mm_struct *mm) +{ + (void)mm; + + return 0; +} + +static inline void ksm_exit(struct mm_struct *mm) +{ + (void)mm; +} + +static inline void vma_lock_init(struct vm_area_struct *vma, bool reset_refcnt) +{ + (void)vma; + (void)reset_refcnt; +} + +static inline void vma_numab_state_init(struct vm_area_struct *vma) +{ + (void)vma; +} + +static inline void vma_numab_state_free(struct vm_area_struct *vma) +{ + (void)vma; +} + +static inline void dup_anon_vma_name(struct vm_area_struct *orig_vma, + struct vm_area_struct *new_vma) +{ + (void)orig_vma; + (void)new_vma; +} + +static inline void free_anon_vma_name(struct vm_area_struct *vma) +{ + (void)vma; +} + +/* Did the driver provide valid mmap hook configuration? */ +static inline bool file_has_valid_mmap_hooks(struct file *file) +{ + bool has_mmap = file->f_op->mmap; + bool has_mmap_prepare = file->f_op->mmap_prepare; + + /* Hooks are mutually exclusive. */ + if (WARN_ON_ONCE(has_mmap && has_mmap_prepare)) + return false; + if (WARN_ON_ONCE(!has_mmap && !has_mmap_prepare)) + return false; + + return true; +} + +static inline int call_mmap(struct file *file, struct vm_area_struct *vma) +{ + if (WARN_ON_ONCE(file->f_op->mmap_prepare)) + return -EINVAL; + + return file->f_op->mmap(file, vma); +} + +static inline int __call_mmap_prepare(struct file *file, + struct vm_area_desc *desc) +{ + return file->f_op->mmap_prepare(desc); +} + +static inline void fixup_hugetlb_reservations(struct vm_area_struct *vma) +{ + (void)vma; +} + +static inline void vma_set_file(struct vm_area_struct *vma, struct file *file) +{ + /* Changing an anonymous vma with this is illegal */ + get_file(file); + swap(vma->vm_file, file); + fput(file); +} + +#endif /* __MM_VMA_INTERNAL_H */ |