diff options
| -rw-r--r-- | include/linux/mm.h | 2 | ||||
| -rw-r--r-- | mm/internal.h | 6 | ||||
| -rw-r--r-- | mm/mmap.c | 2 | ||||
| -rw-r--r-- | mm/mremap.c | 4 | ||||
| -rw-r--r-- | mm/nommu.c | 2 | ||||
| -rw-r--r-- | mm/vma.c | 6 | ||||
| -rw-r--r-- | tools/testing/vma/include/custom.h | 3 | ||||
| -rw-r--r-- | tools/testing/vma/include/dup.h | 9 | ||||
| -rw-r--r-- | tools/testing/vma/main.c | 2 |
9 files changed, 24 insertions, 12 deletions
diff --git a/include/linux/mm.h b/include/linux/mm.h index efb8be5d259c..25ba5816e02b 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -207,8 +207,6 @@ static inline void __mm_zero_struct_page(struct page *page) #define MAPCOUNT_ELF_CORE_MARGIN (5) #define DEFAULT_MAX_MAP_COUNT (USHRT_MAX - MAPCOUNT_ELF_CORE_MARGIN) -extern int sysctl_max_map_count; - extern unsigned long sysctl_user_reserve_kbytes; extern unsigned long sysctl_admin_reserve_kbytes; diff --git a/mm/internal.h b/mm/internal.h index f50a0376b87e..62d80fd37ae1 100644 --- a/mm/internal.h +++ b/mm/internal.h @@ -1863,4 +1863,10 @@ static inline int pmdp_test_and_clear_young_notify(struct vm_area_struct *vma, #endif /* CONFIG_MMU_NOTIFIER */ +extern int sysctl_max_map_count; +static inline int get_sysctl_max_map_count(void) +{ + return READ_ONCE(sysctl_max_map_count); +} + #endif /* __MM_INTERNAL_H */ diff --git a/mm/mmap.c b/mm/mmap.c index 843160946aa5..79544d893411 100644 --- a/mm/mmap.c +++ b/mm/mmap.c @@ -375,7 +375,7 @@ unsigned long do_mmap(struct file *file, unsigned long addr, return -EOVERFLOW; /* Too many mappings? */ - if (mm->map_count > sysctl_max_map_count) + if (mm->map_count > get_sysctl_max_map_count()) return -ENOMEM; /* diff --git a/mm/mremap.c b/mm/mremap.c index e8c3021dd841..ba6c690f6c1b 100644 --- a/mm/mremap.c +++ b/mm/mremap.c @@ -1045,7 +1045,7 @@ static unsigned long prep_move_vma(struct vma_remap_struct *vrm) * which may not merge, then (if MREMAP_DONTUNMAP is not set) unmap the * source, which may split, causing a net increase of 2 mappings. */ - if (current->mm->map_count + 2 > sysctl_max_map_count) + if (current->mm->map_count + 2 > get_sysctl_max_map_count()) return -ENOMEM; if (vma->vm_ops && vma->vm_ops->may_split) { @@ -1813,7 +1813,7 @@ static unsigned long check_mremap_params(struct vma_remap_struct *vrm) * net increased map count of 2. In move_vma() we check for headroom of * 2 additional mappings, so check early to avoid bailing out then. */ - if (current->mm->map_count + 4 > sysctl_max_map_count) + if (current->mm->map_count + 4 > get_sysctl_max_map_count()) return -ENOMEM; return 0; diff --git a/mm/nommu.c b/mm/nommu.c index c3a23b082adb..ed3934bc2de4 100644 --- a/mm/nommu.c +++ b/mm/nommu.c @@ -1317,7 +1317,7 @@ static int split_vma(struct vma_iterator *vmi, struct vm_area_struct *vma, return -ENOMEM; mm = vma->vm_mm; - if (mm->map_count >= sysctl_max_map_count) + if (mm->map_count >= get_sysctl_max_map_count()) return -ENOMEM; region = kmem_cache_alloc(vm_region_jar, GFP_KERNEL); @@ -590,7 +590,7 @@ out_free_vma: static int split_vma(struct vma_iterator *vmi, struct vm_area_struct *vma, unsigned long addr, int new_below) { - if (vma->vm_mm->map_count >= sysctl_max_map_count) + if (vma->vm_mm->map_count >= get_sysctl_max_map_count()) return -ENOMEM; return __split_vma(vmi, vma, addr, new_below); @@ -1394,7 +1394,7 @@ static int vms_gather_munmap_vmas(struct vma_munmap_struct *vms, * its limit temporarily, to help free resources as expected. */ if (vms->end < vms->vma->vm_end && - vms->vma->vm_mm->map_count >= sysctl_max_map_count) { + vms->vma->vm_mm->map_count >= get_sysctl_max_map_count()) { error = -ENOMEM; goto map_count_exceeded; } @@ -2868,7 +2868,7 @@ int do_brk_flags(struct vma_iterator *vmi, struct vm_area_struct *vma, if (!may_expand_vm(mm, vm_flags, len >> PAGE_SHIFT)) return -ENOMEM; - if (mm->map_count > sysctl_max_map_count) + if (mm->map_count > get_sysctl_max_map_count()) return -ENOMEM; if (security_vm_enough_memory_mm(mm, len >> PAGE_SHIFT)) diff --git a/tools/testing/vma/include/custom.h b/tools/testing/vma/include/custom.h index 7150e09122b2..6c62a38a2f6f 100644 --- a/tools/testing/vma/include/custom.h +++ b/tools/testing/vma/include/custom.h @@ -21,9 +21,6 @@ extern unsigned long dac_mmap_min_addr; #define VM_BUG_ON(_expr) (BUG_ON(_expr)) #define VM_BUG_ON_VMA(_expr, _vma) (BUG_ON(_expr)) -/* We hardcode this for now. */ -#define sysctl_max_map_count 0x1000000UL - #define TASK_SIZE ((1ul << 47)-PAGE_SIZE) /* diff --git a/tools/testing/vma/include/dup.h b/tools/testing/vma/include/dup.h index 5eb313beb43d..8865ffe046d8 100644 --- a/tools/testing/vma/include/dup.h +++ b/tools/testing/vma/include/dup.h @@ -419,6 +419,9 @@ struct vma_iterator { #define EMPTY_VMA_FLAGS ((vma_flags_t){ }) +#define MAPCOUNT_ELF_CORE_MARGIN (5) +#define DEFAULT_MAX_MAP_COUNT (USHRT_MAX - MAPCOUNT_ELF_CORE_MARGIN) + /* What action should be taken after an .mmap_prepare call is complete? */ enum mmap_action_type { MMAP_NOTHING, /* Mapping is complete, no further action. */ @@ -1342,3 +1345,9 @@ static inline void vma_set_file(struct vm_area_struct *vma, struct file *file) swap(vma->vm_file, file); fput(file); } + +extern int sysctl_max_map_count; +static inline int get_sysctl_max_map_count(void) +{ + return READ_ONCE(sysctl_max_map_count); +} diff --git a/tools/testing/vma/main.c b/tools/testing/vma/main.c index 49b09e97a51f..18338f5d29e0 100644 --- a/tools/testing/vma/main.c +++ b/tools/testing/vma/main.c @@ -14,6 +14,8 @@ #include "tests/mmap.c" #include "tests/vma.c" +int sysctl_max_map_count __read_mostly = DEFAULT_MAX_MAP_COUNT; + /* Helper functions which utilise static kernel functions. */ struct vm_area_struct *merge_existing(struct vma_merge_struct *vmg) |