From 35d7bdc86031a2c1ae05ac27dfa93b2acdcbaecc Mon Sep 17 00:00:00 2001 From: David Hildenbrand Date: Fri, 23 Apr 2021 10:20:25 +0200 Subject: kernel/fork: factor out replacing the current MM exe_file MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Let's factor the main logic out into replace_mm_exe_file(), such that all mm->exe_file logic is contained in kernel/fork.c. While at it, perform some simple cleanups that are possible now that we're simplifying the individual functions. Acked-by: Christian Brauner Acked-by: "Eric W. Biederman" Acked-by: Christian König Signed-off-by: David Hildenbrand --- kernel/sys.c | 33 +-------------------------------- 1 file changed, 1 insertion(+), 32 deletions(-) (limited to 'kernel/sys.c') diff --git a/kernel/sys.c b/kernel/sys.c index ef1a78f5d71c..30c12e54585a 100644 --- a/kernel/sys.c +++ b/kernel/sys.c @@ -1846,7 +1846,6 @@ SYSCALL_DEFINE1(umask, int, mask) static int prctl_set_mm_exe_file(struct mm_struct *mm, unsigned int fd) { struct fd exe; - struct file *old_exe, *exe_file; struct inode *inode; int err; @@ -1869,40 +1868,10 @@ static int prctl_set_mm_exe_file(struct mm_struct *mm, unsigned int fd) if (err) goto exit; - /* - * Forbid mm->exe_file change if old file still mapped. - */ - exe_file = get_mm_exe_file(mm); - err = -EBUSY; - if (exe_file) { - struct vm_area_struct *vma; - - mmap_read_lock(mm); - for (vma = mm->mmap; vma; vma = vma->vm_next) { - if (!vma->vm_file) - continue; - if (path_equal(&vma->vm_file->f_path, - &exe_file->f_path)) - goto exit_err; - } - - mmap_read_unlock(mm); - fput(exe_file); - } - - err = 0; - /* set the new file, lockless */ - get_file(exe.file); - old_exe = xchg(&mm->exe_file, exe.file); - if (old_exe) - fput(old_exe); + err = replace_mm_exe_file(mm, exe.file); exit: fdput(exe); return err; -exit_err: - mmap_read_unlock(mm); - fput(exe_file); - goto exit; } /* -- cgit v1.2.3-59-g8ed1b