linux-kernel - Re: [PATCH v2] f2fs: fix readdir incorrectness

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Date:	Fri, 05 Jul 2013 17:28:12 +0900
From:	Jaegeuk Kim <jaegeuk.kim@...sung.com>
To:	linux-fsdevel@...r.kernel.org
Cc:	linux-kernel@...r.kernel.org,
	linux-f2fs-devel@...ts.sourceforge.net,
	Al Viro <viro@...iv.linux.org.uk>
Subject: Re: [PATCH v2] f2fs: fix readdir incorrectness

Chang log from v1:
 o fix another scenario

>From 2ee3c8144187ab230d0f47f9b95e5406af87ada8 Mon Sep 17 00:00:00 2001
From: Jaegeuk Kim <jaegeuk.kim@...sung.com>
Date: Fri, 5 Jul 2013 14:06:04 +0900
Subject: [PATCH] f2fs: fix readdir incorrectness
Cc: linux-fsdevel@...r.kernel.org, linux-kernel@...r.kernel.org,
linux-f2fs-devel@...ts.sourceforge.net

In the previous Al Viro's readdir patch set, there occurs a bug when
running
xfstest: 006 as follows.

[Error output]
alpha size = 4, name length = 6, total files = 4096, nproc=1
1023 files created
rm: cannot remove `/mnt/f2fs/permname.15150/a': Directory not empty

[Correct output]
alpha size = 4, name length = 6, total files = 4096, nproc=1
4097 files created

This bug is due to the misupdate of directory position in ctx.
So, this patch fixes this.

CC: Al Viro <viro@...iv.linux.org.uk>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@...sung.com>
---
 fs/f2fs/dir.c | 16 ++++++++--------
 1 file changed, 8 insertions(+), 8 deletions(-)

diff --git a/fs/f2fs/dir.c b/fs/f2fs/dir.c
index 9d1cd42..dffc4f7 100644
--- a/fs/f2fs/dir.c
+++ b/fs/f2fs/dir.c
@@ -634,19 +634,19 @@ static int f2fs_readdir(struct file *file, struct
dir_context *ctx)
 			if (bit_pos >= NR_DENTRY_IN_BLOCK)
 				break;
 
-			ctx->pos += bit_pos - start_bit_pos;
 			de = &dentry_blk->dentry[bit_pos];
 			if (de->file_type < F2FS_FT_MAX)
 				d_type = f2fs_filetype_table[de->file_type];
 			else
 				d_type = DT_UNKNOWN;
 			if (!dir_emit(ctx,
-				      dentry_blk->filename[bit_pos],
-				      le16_to_cpu(de->name_len),
-				      le32_to_cpu(de->ino), d_type))
-				goto success;
-			slots = GET_DENTRY_SLOTS(le16_to_cpu(de->name_len));
-			bit_pos += slots;
+					dentry_blk->filename[bit_pos],
+					le16_to_cpu(de->name_len),
+					le32_to_cpu(de->ino), d_type))
+				goto stop;
+
+			bit_pos += GET_DENTRY_SLOTS(le16_to_cpu(de->name_len));
+			ctx->pos = n * NR_DENTRY_IN_BLOCK + bit_ops;
 		}
 		bit_pos = 0;
 		ctx->pos = (n + 1) * NR_DENTRY_IN_BLOCK;
@@ -654,7 +654,7 @@ static int f2fs_readdir(struct file *file, struct
dir_context *ctx)
 		f2fs_put_page(dentry_page, 1);
 		dentry_page = NULL;
 	}
-success:
+stop:
 	if (dentry_page && !IS_ERR(dentry_page)) {
 		kunmap(dentry_page);
 		f2fs_put_page(dentry_page, 1);
-- 
1.8.3.1.437.g0dbd812



-- 
Jaegeuk Kim
Samsung

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