Commit 7dce08b9 authored Jul 16, 2024 by Scott Mayhew Committed by Wang Zhaolong Jul 16, 2024

nfs: ensure correct writeback errors are returned on close()

mainline inclusion
from mainline-v5.9-rc1
commit 67dd23f9
category: bugfix
bugzilla: https://gitee.com/openeuler/kernel/issues/IACBGS

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=67dd23f9e6fbaf163431912ef5599c5e0693476c



--------------------------------

nfs_wb_all() calls filemap_write_and_wait(), which uses
filemap_check_errors() to determine the error to return.
filemap_check_errors() only looks at the mapping->flags and will
therefore only return either -ENOSPC or -EIO.  To ensure that the
correct error is returned on close(), nfs{,4}_file_flush() should call
filemap_check_wb_err() which looks at the errseq value in
mapping->wb_err without consuming it.

Fixes: 6fbda89b ("NFS: Replace custom error reporting mechanism with
generic one")
Signed-off-by: Scott Mayhew <smayhew@redhat.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Wang Zhaolong <wangzhaolong1@huawei.com>

parent f73d3199

fs/nfs/file.c

+4 −1

Original line number	Diff line number	Diff line
		@@ -140,6 +140,7 @@ static int
		nfs_file_flush(struct file *file, fl_owner_t id)
		{
		struct inode *inode = file_inode(file);
		errseq_t since;

		dprintk("NFS: flush(%pD2)\n", file);

		@@ -148,7 +149,9 @@ nfs_file_flush(struct file *file, fl_owner_t id)
		return 0;

		/* Flush writes to the server and return any errors */
		return nfs_wb_all(inode);
		since = filemap_sample_wb_err(file->f_mapping);
		nfs_wb_all(inode);
		return filemap_check_wb_err(file->f_mapping, since);
		}

		ssize_t

fs/nfs/nfs4file.c

+4 −1

Original line number	Diff line number	Diff line
		@@ -113,6 +113,7 @@ static int
		nfs4_file_flush(struct file *file, fl_owner_t id)
		{
		struct inode *inode = file_inode(file);
		errseq_t since;

		dprintk("NFS: flush(%pD2)\n", file);

		@@ -128,7 +129,9 @@ nfs4_file_flush(struct file *file, fl_owner_t id)
		return filemap_fdatawrite(file->f_mapping);

		/* Flush writes to the server and return any errors */
		return nfs_wb_all(inode);
		since = filemap_sample_wb_err(file->f_mapping);
		nfs_wb_all(inode);
		return filemap_check_wb_err(file->f_mapping, since);
		}

		#ifdef CONFIG_NFS_V4_2