diff options
Diffstat (limited to 'mm/mmap.c')
| -rw-r--r-- | mm/mmap.c | 22 |
1 files changed, 14 insertions, 8 deletions
diff --git a/mm/mmap.c b/mm/mmap.c index 41eb48d9b527..2d6a6662edb9 100644 --- a/mm/mmap.c +++ b/mm/mmap.c @@ -45,6 +45,7 @@ #include <linux/moduleparam.h> #include <linux/pkeys.h> #include <linux/oom.h> +#include <linux/sched/mm.h> #include <linux/uaccess.h> #include <asm/cacheflush.h> @@ -2525,7 +2526,8 @@ find_extend_vma(struct mm_struct *mm, unsigned long addr) vma = find_vma_prev(mm, addr, &prev); if (vma && (vma->vm_start <= addr)) return vma; - if (!prev || expand_stack(prev, addr)) + /* don't alter vm_end if the coredump is running */ + if (!prev || !mmget_still_valid(mm) || expand_stack(prev, addr)) return NULL; if (prev->vm_flags & VM_LOCKED) populate_vma_page_range(prev, addr, prev->vm_end, NULL); @@ -2551,6 +2553,9 @@ find_extend_vma(struct mm_struct *mm, unsigned long addr) return vma; if (!(vma->vm_flags & VM_GROWSDOWN)) return NULL; + /* don't alter vm_start if the coredump is running */ + if (!mmget_still_valid(mm)) + return NULL; start = vma->vm_start; if (expand_stack(vma, addr)) return NULL; @@ -2730,9 +2735,17 @@ int __do_munmap(struct mm_struct *mm, unsigned long start, size_t len, return -EINVAL; len = PAGE_ALIGN(len); + end = start + len; if (len == 0) return -EINVAL; + /* + * arch_unmap() might do unmaps itself. It must be called + * and finish any rbtree manipulation before this code + * runs and also starts to manipulate the rbtree. + */ + arch_unmap(mm, start, end); + /* Find the first overlapping VMA */ vma = find_vma(mm, start); if (!vma) @@ -2741,7 +2754,6 @@ int __do_munmap(struct mm_struct *mm, unsigned long start, size_t len, /* we have start < vma->vm_end */ /* if it doesn't overlap, we have nothing.. */ - end = start + len; if (vma->vm_start >= end) return 0; @@ -2811,12 +2823,6 @@ int __do_munmap(struct mm_struct *mm, unsigned long start, size_t len, /* Detach vmas from rbtree */ detach_vmas_to_be_unmapped(mm, vma, prev, end); - /* - * mpx unmap needs to be called with mmap_sem held for write. - * It is safe to call it before unmap_region(). - */ - arch_unmap(mm, vma, start, end); - if (downgrade) downgrade_write(&mm->mmap_sem); |