linux-ext4 - [PATCH v2] ext4: fix fast commit may miss tracking range for FALLOC_FL_ZERO

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [thread-next>] [day] [month] [year] [list]

Message-Id: <20211221022839.374606-1-yinxin.x@bytedance.com>
Date:   Tue, 21 Dec 2021 10:28:39 +0800
From:   Xin Yin <yinxin.x@...edance.com>
To:     harshadshirwadkar@...il.com, tytso@....edu,
        adilger.kernel@...ger.ca
Cc:     linux-ext4@...r.kernel.org, linux-kernel@...r.kernel.org,
        Xin Yin <yinxin.x@...edance.com>
Subject: [PATCH v2] ext4: fix fast commit may miss tracking range for FALLOC_FL_ZERO_RANGE

when call falloc with FALLOC_FL_ZERO_RANGE, to set an range to unwritten,
which has been already initialized. If the range is align to blocksize,
fast commit will not track range for this change.

Also track range for unwritten range in ext4_map_blocks().

Signed-off-by: Xin Yin <yinxin.x@...edance.com>
---
v2: change to track unwritten range in ext4_map_blocks()
---
 fs/ext4/extents.c | 2 --
 fs/ext4/inode.c   | 7 ++++---
 2 files changed, 4 insertions(+), 5 deletions(-)

diff --git a/fs/ext4/extents.c b/fs/ext4/extents.c
index 9229ab1f99c5..6bce319f3bcd 100644
--- a/fs/ext4/extents.c
+++ b/fs/ext4/extents.c
@@ -4599,8 +4599,6 @@ static long ext4_zero_range(struct file *file, loff_t offset,
 	ret = ext4_mark_inode_dirty(handle, inode);
 	if (unlikely(ret))
 		goto out_handle;
-	ext4_fc_track_range(handle, inode, offset >> inode->i_sb->s_blocksize_bits,
-			(offset + len - 1) >> inode->i_sb->s_blocksize_bits);
 	/* Zero out partial block at the edges of the range */
 	ret = ext4_zero_partial_blocks(handle, inode, offset, len);
 	if (ret >= 0)
diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c
index 0afab6d5c65b..47ad4b8cb503 100644
--- a/fs/ext4/inode.c
+++ b/fs/ext4/inode.c
@@ -741,10 +741,11 @@ int ext4_map_blocks(handle_t *handle, struct inode *inode,
 			if (ret)
 				return ret;
 		}
-		ext4_fc_track_range(handle, inode, map->m_lblk,
-			    map->m_lblk + map->m_len - 1);
 	}
-
+	if (retval > 0 && (map->m_flags & EXT4_MAP_UNWRITTEN ||
+				map->m_flags & EXT4_MAP_MAPPED))
+		ext4_fc_track_range(handle, inode, map->m_lblk,
+					map->m_lblk + map->m_len - 1);
 	if (retval < 0)
 		ext_debug(inode, "failed with err %d\n", retval);
 	return retval;
-- 
2.20.1