From 6f65360b49960745de77f33cc7d14eb6918e8ed4 Mon Sep 17 00:00:00 2001 From: Charan Teja Reddy Date: Mon, 20 Sep 2021 11:03:53 +0530 Subject: [PATCH] mm/madvise: use mmap_sem lock from passed mm_struct Use the mmap_sem lock from passed 'mm' rather than the 'current' as it is required because of the patchset[1]. The commit f4fa8d937edf ("mm: madvise: fix vma user-after-free") changed the 'mmap_sem' to use from 'current' instead of 'mm' context. Revert it. Link: [1] https://patchwork.kernel.org/project/linux-mm/patch/20200302193630.68771-2-minchan@kernel.org/. Change-Id: Ifc9deb2a5f0775c2bc97c85db3584f61fa3a43ae Signed-off-by: Charan Teja Reddy Signed-off-by: Srinivasarao P --- mm/madvise.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/mm/madvise.c b/mm/madvise.c index a4a5e4048ef4..72668d2b9352 100644 --- a/mm/madvise.c +++ b/mm/madvise.c @@ -298,7 +298,7 @@ static long madvise_willneed(struct vm_area_struct *vma, get_file(file); offset = (loff_t)(start - vma->vm_start) + ((loff_t)vma->vm_pgoff << PAGE_SHIFT); - up_read(¤t->mm->mmap_sem); + up_read(&mm->mmap_sem); vfs_fadvise(file, offset, end - start, POSIX_FADV_WILLNEED); fput(file); down_read(&mm->mmap_sem);