[Ocfs2-devel] FAILED: patch "[PATCH] ocfs2: fix data corruption after failed write" failed to apply to 4.19-stable tree - gregkh--- via Ocfs2-devel

From: gregkh--- via Ocfs2-devel <ocfs2-devel@oss.oracle.com>
To: ocfs2-devel@oss.oracle.com, akpm@linux-foundation.org,
	gechangwei@live.cn, ghe@suse.com, jack@suse.cz,
	jlbec@evilplan.org, joseph.qi@linux.alibaba.com,
	junxiao.bi@oracle.com, mark@fasheh.com, piaojun@huawei.com,
	stable@vger.kernel.org
Cc: stable@vger.kernel.org
Subject: [Ocfs2-devel] FAILED: patch "[PATCH] ocfs2: fix data corruption	after failed write" failed to apply to 4.19-stable tree
Date: Mon, 20 Mar 2023 12:57:27 +0100	[thread overview]
Message-ID: <16793134471133@kroah.com> (raw)


The patch below does not apply to the 4.19-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable@vger.kernel.org>.

To reproduce the conflict and resubmit, you may use the following commands:

git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-4.19.y
git checkout FETCH_HEAD
git cherry-pick -x 90410bcf873cf05f54a32183afff0161f44f9715
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable@vger.kernel.org>' --in-reply-to '16793134471133@kroah.com' --subject-prefix 'PATCH 4.19.y' HEAD^..

Possible dependencies:

90410bcf873c ("ocfs2: fix data corruption after failed write")

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From 90410bcf873cf05f54a32183afff0161f44f9715 Mon Sep 17 00:00:00 2001
From: Jan Kara via Ocfs2-devel <ocfs2-devel@oss.oracle.com>
Date: Thu, 2 Mar 2023 16:38:43 +0100
Subject: [PATCH] ocfs2: fix data corruption after failed write

When buffered write fails to copy data into underlying page cache page,
ocfs2_write_end_nolock() just zeroes out and dirties the page.  This can
leave dirty page beyond EOF and if page writeback tries to write this page
before write succeeds and expands i_size, page gets into inconsistent
state where page dirty bit is clear but buffer dirty bits stay set
resulting in page data never getting written and so data copied to the
page is lost.  Fix the problem by invalidating page beyond EOF after
failed write.

Link: https://lkml.kernel.org/r/20230302153843.18499-1-jack@suse.cz
Fixes: 6dbf7bb55598 ("fs: Don't invalidate page buffers in block_write_full_page()")
Signed-off-by: Jan Kara <jack@suse.cz>
Reviewed-by: Joseph Qi <joseph.qi@linux.alibaba.com>
Cc: Mark Fasheh <mark@fasheh.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Junxiao Bi <junxiao.bi@oracle.com>
Cc: Changwei Ge <gechangwei@live.cn>
Cc: Gang He <ghe@suse.com>
Cc: Jun Piao <piaojun@huawei.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

diff --git a/fs/ocfs2/aops.c b/fs/ocfs2/aops.c
index 1d65f6ef00ca..0394505fdce3 100644
--- a/fs/ocfs2/aops.c
+++ b/fs/ocfs2/aops.c
@@ -1977,11 +1977,26 @@ int ocfs2_write_end_nolock(struct address_space *mapping,
 	}
 
 	if (unlikely(copied < len) && wc->w_target_page) {
+		loff_t new_isize;
+
 		if (!PageUptodate(wc->w_target_page))
 			copied = 0;
 
-		ocfs2_zero_new_buffers(wc->w_target_page, start+copied,
-				       start+len);
+		new_isize = max_t(loff_t, i_size_read(inode), pos + copied);
+		if (new_isize > page_offset(wc->w_target_page))
+			ocfs2_zero_new_buffers(wc->w_target_page, start+copied,
+					       start+len);
+		else {
+			/*
+			 * When page is fully beyond new isize (data copy
+			 * failed), do not bother zeroing the page. Invalidate
+			 * it instead so that writeback does not get confused
+			 * put page & buffer dirty bits into inconsistent
+			 * state.
+			 */
+			block_invalidate_folio(page_folio(wc->w_target_page),
+						0, PAGE_SIZE);
+		}
 	}
 	if (wc->w_target_page)
 		flush_dcache_page(wc->w_target_page);


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