From: Gonzalo Matias Juarez Tello Date: Tue, 29 Jun 2021 02:38:39 +0000 (-0700) Subject: mm/mmap.c: logic of find_vma_intersection repeated in __do_munmap X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=78d9cf6041b968cc881fd22e25e2662d1cec4dba;p=linux.git mm/mmap.c: logic of find_vma_intersection repeated in __do_munmap Logic of find_vma_intersection() is repeated in __do_munmap(). Also, prev is assigned a value before checking vma->vm_start >= end which might end up on a return statement making that assignment useless. Calling find_vma_intersection() checks that condition and returns NULL if no vma is found, hence only the !vma check is needed in __do_munmap(). Link: https://lkml.kernel.org/r/20210409162129.18313-1-gmjuareztello@gmail.com Signed-off-by: Gonzalo Matias Juarez Tello Reviewed-by: Andrew Morton Reviewed-by: David Hildenbrand Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- diff --git a/mm/mmap.c b/mm/mmap.c index f9a61f7dc5403..bb128a42557e8 100644 --- a/mm/mmap.c +++ b/mm/mmap.c @@ -2828,16 +2828,11 @@ int __do_munmap(struct mm_struct *mm, unsigned long start, size_t len, */ arch_unmap(mm, start, end); - /* Find the first overlapping VMA */ - vma = find_vma(mm, start); + /* Find the first overlapping VMA where start < vma->vm_end */ + vma = find_vma_intersection(mm, start, end); if (!vma) return 0; prev = vma->vm_prev; - /* we have start < vma->vm_end */ - - /* if it doesn't overlap, we have nothing.. */ - if (vma->vm_start >= end) - return 0; /* * If we need to split any vma, do it now to save pain later.