[block:for-5.12/io_uring 29/34] fs/io_uring.c:4494:6: warning: variable 'file' is used uninitialized whenever 'if' condition is true

[block:for-5.12/io_uring 29/34] fs/io_uring.c:4494:6: warning: variable 'file' is used uninitialized whenever 'if' condition is true

[kernel test robot]

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tree:   https://git.kernel.org/pub/scm/linux/kernel/git/axboe/linux-block.git for-5.12/io_uring
head:   ddebaa7f62a202b40378a5a71d1a51737277d773
commit: 21e779401a16d6f6ca4b5570cdd9b19a29d68bab [29/34] io_uring: get rid of intermediate IORING_OP_CLOSE stage
config: x86_64-randconfig-a003-20210120 (attached as .config)
compiler: clang version 12.0.0 (https://github.com/llvm/llvm-project 22b68440e1647e16b5ee24b924986207173c02d1)
reproduce (this is a W=1 build):
        wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
        chmod +x ~/bin/make.cross
        # install x86_64 cross compiling tool for clang build
        # apt-get install binutils-x86-64-linux-gnu
        # https://git.kernel.org/pub/scm/linux/kernel/git/axboe/linux-block.git/commit/?id=21e779401a16d6f6ca4b5570cdd9b19a29d68bab
        git remote add block https://git.kernel.org/pub/scm/linux/kernel/git/axboe/linux-block.git
        git fetch --no-tags block for-5.12/io_uring
        git checkout 21e779401a16d6f6ca4b5570cdd9b19a29d68bab
        # save the attached .config to linux build tree
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross ARCH=x86_64 

If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <lkp@intel.com>

All warnings (new ones prefixed by >>):

>> fs/io_uring.c:4494:6: warning: variable 'file' is used uninitialized whenever 'if' condition is true [-Wsometimes-uninitialized]
           if (close->fd >= fdt->max_fds) {
               ^~~~~~~~~~~~~~~~~~~~~~~~~
   fs/io_uring.c:4523:7: note: uninitialized use occurs here
           fput(file);
                ^~~~
   fs/io_uring.c:4494:2: note: remove the 'if' if its condition is always false
           if (close->fd >= fdt->max_fds) {
           ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
   fs/io_uring.c:4488:19: note: initialize the variable 'file' to silence this warning
           struct file *file;
                            ^
                             = NULL
   1 warning generated.


vim +4494 fs/io_uring.c

  4481	
  4482	static int io_close(struct io_kiocb *req, bool force_nonblock,
  4483			    struct io_comp_state *cs)
  4484	{
  4485		struct files_struct *files = current->files;
  4486		struct io_close *close = &req->close;
  4487		struct fdtable *fdt;
  4488		struct file *file;
  4489		int ret;
  4490	
  4491		ret = -EBADF;
  4492		spin_lock(&files->file_lock);
  4493		fdt = files_fdtable(files);
> 4494		if (close->fd >= fdt->max_fds) {
  4495			spin_unlock(&files->file_lock);
  4496			goto err;
  4497		}
  4498		file = fdt->fd[close->fd];
  4499		if (!file) {
  4500			spin_unlock(&files->file_lock);
  4501			goto err;
  4502		}
  4503	
  4504		/* if the file has a flush method, be safe and punt to async */
  4505		if (file->f_op->flush && force_nonblock) {
  4506			spin_unlock(&files->file_lock);
  4507			return -EAGAIN;
  4508		}
  4509	
  4510		ret = __close_fd_get_file(close->fd, &file);
  4511		spin_unlock(&files->file_lock);
  4512		if (ret < 0) {
  4513			if (ret == -ENOENT)
  4514				ret = -EBADF;
  4515			goto err;
  4516		}
  4517	
  4518		/* No ->flush() or already async, safely close from here */
  4519		ret = filp_close(file, current->files);
  4520	err:
  4521		if (ret < 0)
  4522			req_set_fail_links(req);
  4523		fput(file);
  4524		__io_req_complete(req, ret, 0, cs);
  4525		return 0;
  4526	}
  4527	

---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org

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