FAILED: patch "[PATCH] ext4: fix rec_len verify error" failed to apply to 4.19-stable tree

FAILED: patch "[PATCH] ext4: fix rec_len verify error" failed to apply to 4.19-stable tree

[gregkh]

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 7fda67e8c3ab6069f75888f67958a6d30454a9f6
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable@vger.kernel.org>' --in-reply-to '2023092055-disband-unveiling-f6cc@gregkh' --subject-prefix 'PATCH 4.19.y' HEAD^..

Possible dependencies:

7fda67e8c3ab ("ext4: fix rec_len verify error")
46c116b920eb ("ext4: verify dir block before splitting it")
f036adb39976 ("ext4: rename "dirent_csum" functions to use "dirblock"")
b886ee3e778e ("ext4: Support case-insensitive file name lookups")

thanks,

greg k-h

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

From 7fda67e8c3ab6069f75888f67958a6d30454a9f6 Mon Sep 17 00:00:00 2001
From: Shida Zhang <zhangshida@kylinos.cn>
Date: Thu, 3 Aug 2023 14:09:38 +0800
Subject: [PATCH] ext4: fix rec_len verify error

With the configuration PAGE_SIZE 64k and filesystem blocksize 64k,
a problem occurred when more than 13 million files were directly created
under a directory:

EXT4-fs error (device xx): ext4_dx_csum_set:492: inode #xxxx: comm xxxxx: dir seems corrupt?  Run e2fsck -D.
EXT4-fs error (device xx): ext4_dx_csum_verify:463: inode #xxxx: comm xxxxx: dir seems corrupt?  Run e2fsck -D.
EXT4-fs error (device xx): dx_probe:856: inode #xxxx: block 8188: comm xxxxx: Directory index failed checksum

When enough files are created, the fake_dirent->reclen will be 0xffff.
it doesn't equal to the blocksize 65536, i.e. 0x10000.

But it is not the same condition when blocksize equals to 4k.
when enough files are created, the fake_dirent->reclen will be 0x1000.
it equals to the blocksize 4k, i.e. 0x1000.

The problem seems to be related to the limitation of the 16-bit field
when the blocksize is set to 64k.
To address this, helpers like ext4_rec_len_{from,to}_disk has already
been introduced to complete the conversion between the encoded and the
plain form of rec_len.

So fix this one by using the helper, and all the other in this file too.

Cc: stable@kernel.org
Fixes: dbe89444042a ("ext4: Calculate and verify checksums for htree nodes")
Suggested-by: Andreas Dilger <adilger@dilger.ca>
Suggested-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Shida Zhang <zhangshida@kylinos.cn>
Reviewed-by: Andreas Dilger <adilger@dilger.ca>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Link: https://lore.kernel.org/r/20230803060938.1929759-1-zhangshida@kylinos.cn
Signed-off-by: Theodore Ts'o <tytso@mit.edu>

diff --git a/fs/ext4/namei.c b/fs/ext4/namei.c
index c0f0b4e2413b..c1ceccab05f5 100644
--- a/fs/ext4/namei.c
+++ b/fs/ext4/namei.c
@@ -343,17 +343,17 @@ static struct ext4_dir_entry_tail *get_dirent_tail(struct inode *inode,
 						   struct buffer_head *bh)
 {
 	struct ext4_dir_entry_tail *t;
+	int blocksize = EXT4_BLOCK_SIZE(inode->i_sb);
 
 #ifdef PARANOID
 	struct ext4_dir_entry *d, *top;
 
 	d = (struct ext4_dir_entry *)bh->b_data;
 	top = (struct ext4_dir_entry *)(bh->b_data +
-		(EXT4_BLOCK_SIZE(inode->i_sb) -
-		 sizeof(struct ext4_dir_entry_tail)));
-	while (d < top && d->rec_len)
+		(blocksize - sizeof(struct ext4_dir_entry_tail)));
+	while (d < top && ext4_rec_len_from_disk(d->rec_len, blocksize))
 		d = (struct ext4_dir_entry *)(((void *)d) +
-		    le16_to_cpu(d->rec_len));
+		    ext4_rec_len_from_disk(d->rec_len, blocksize));
 
 	if (d != top)
 		return NULL;
@@ -364,7 +364,8 @@ static struct ext4_dir_entry_tail *get_dirent_tail(struct inode *inode,
 #endif
 
 	if (t->det_reserved_zero1 ||
-	    le16_to_cpu(t->det_rec_len) != sizeof(struct ext4_dir_entry_tail) ||
+	    (ext4_rec_len_from_disk(t->det_rec_len, blocksize) !=
+	     sizeof(struct ext4_dir_entry_tail)) ||
 	    t->det_reserved_zero2 ||
 	    t->det_reserved_ft != EXT4_FT_DIR_CSUM)
 		return NULL;
@@ -445,13 +446,14 @@ static struct dx_countlimit *get_dx_countlimit(struct inode *inode,
 	struct ext4_dir_entry *dp;
 	struct dx_root_info *root;
 	int count_offset;
+	int blocksize = EXT4_BLOCK_SIZE(inode->i_sb);
+	unsigned int rlen = ext4_rec_len_from_disk(dirent->rec_len, blocksize);
 
-	if (le16_to_cpu(dirent->rec_len) == EXT4_BLOCK_SIZE(inode->i_sb))
+	if (rlen == blocksize)
 		count_offset = 8;
-	else if (le16_to_cpu(dirent->rec_len) == 12) {
+	else if (rlen == 12) {
 		dp = (struct ext4_dir_entry *)(((void *)dirent) + 12);
-		if (le16_to_cpu(dp->rec_len) !=
-		    EXT4_BLOCK_SIZE(inode->i_sb) - 12)
+		if (ext4_rec_len_from_disk(dp->rec_len, blocksize) != blocksize - 12)
 			return NULL;
 		root = (struct dx_root_info *)(((void *)dp + 12));
 		if (root->reserved_zero ||
@@ -1315,6 +1317,7 @@ static int dx_make_map(struct inode *dir, struct buffer_head *bh,
 	unsigned int buflen = bh->b_size;
 	char *base = bh->b_data;
 	struct dx_hash_info h = *hinfo;
+	int blocksize = EXT4_BLOCK_SIZE(dir->i_sb);
 
 	if (ext4_has_metadata_csum(dir->i_sb))
 		buflen -= sizeof(struct ext4_dir_entry_tail);
@@ -1335,11 +1338,12 @@ static int dx_make_map(struct inode *dir, struct buffer_head *bh,
 			map_tail--;
 			map_tail->hash = h.hash;
 			map_tail->offs = ((char *) de - base)>>2;
-			map_tail->size = le16_to_cpu(de->rec_len);
+			map_tail->size = ext4_rec_len_from_disk(de->rec_len,
+								blocksize);
 			count++;
 			cond_resched();
 		}
-		de = ext4_next_entry(de, dir->i_sb->s_blocksize);
+		de = ext4_next_entry(de, blocksize);
 	}
 	return count;
 }

[PATCH] ext4: fix rec_len verify error

[zhangshida]

From: Shida Zhang <zhangshida@kylinos.cn>

[ Upstream commit 7fda67e8c3ab6069f75888f67958a6d30454a9f6 ]

With the configuration PAGE_SIZE 64k and filesystem blocksize 64k,
a problem occurred when more than 13 million files were directly created
under a directory:

EXT4-fs error (device xx): ext4_dx_csum_set:492: inode #xxxx: comm xxxxx: dir seems corrupt?  Run e2fsck -D.
EXT4-fs error (device xx): ext4_dx_csum_verify:463: inode #xxxx: comm xxxxx: dir seems corrupt?  Run e2fsck -D.
EXT4-fs error (device xx): dx_probe:856: inode #xxxx: block 8188: comm xxxxx: Directory index failed checksum

When enough files are created, the fake_dirent->reclen will be 0xffff.
it doesn't equal to the blocksize 65536, i.e. 0x10000.

But it is not the same condition when blocksize equals to 4k.
when enough files are created, the fake_dirent->reclen will be 0x1000.
it equals to the blocksize 4k, i.e. 0x1000.

The problem seems to be related to the limitation of the 16-bit field
when the blocksize is set to 64k.
To address this, helpers like ext4_rec_len_{from,to}_disk has already
been introduced to complete the conversion between the encoded and the
plain form of rec_len.

So fix this one by using the helper, and all the other in this file too.

Cc: stable@kernel.org
Fixes: dbe89444042a ("ext4: Calculate and verify checksums for htree nodes")
Suggested-by: Andreas Dilger <adilger@dilger.ca>
Suggested-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Shida Zhang <zhangshida@kylinos.cn>
Reviewed-by: Andreas Dilger <adilger@dilger.ca>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Link: https://lore.kernel.org/r/20230803060938.1929759-1-zhangshida@kylinos.cn
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Shida Zhang <zhangshida@kylinos.cn>
---
 fs/ext4/namei.c | 26 +++++++++++++++-----------
 1 file changed, 15 insertions(+), 11 deletions(-)

diff --git a/fs/ext4/namei.c b/fs/ext4/namei.c
index db9bba3473b5..93d392576c12 100644
--- a/fs/ext4/namei.c
+++ b/fs/ext4/namei.c
@@ -322,17 +322,17 @@ static struct ext4_dir_entry_tail *get_dirent_tail(struct inode *inode,
 						   struct ext4_dir_entry *de)
 {
 	struct ext4_dir_entry_tail *t;
+	int blocksize = EXT4_BLOCK_SIZE(inode->i_sb);
 
 #ifdef PARANOID
 	struct ext4_dir_entry *d, *top;
 
 	d = de;
 	top = (struct ext4_dir_entry *)(((void *)de) +
-		(EXT4_BLOCK_SIZE(inode->i_sb) -
-		sizeof(struct ext4_dir_entry_tail)));
-	while (d < top && d->rec_len)
+		(blocksize - sizeof(struct ext4_dir_entry_tail)));
+	while (d < top && ext4_rec_len_from_disk(d->rec_len, blocksize))
 		d = (struct ext4_dir_entry *)(((void *)d) +
-		    le16_to_cpu(d->rec_len));
+		    ext4_rec_len_from_disk(d->rec_len, blocksize));
 
 	if (d != top)
 		return NULL;
@@ -343,7 +343,8 @@ static struct ext4_dir_entry_tail *get_dirent_tail(struct inode *inode,
 #endif
 
 	if (t->det_reserved_zero1 ||
-	    le16_to_cpu(t->det_rec_len) != sizeof(struct ext4_dir_entry_tail) ||
+	    (ext4_rec_len_from_disk(t->det_rec_len, blocksize) !=
+	     sizeof(struct ext4_dir_entry_tail)) ||
 	    t->det_reserved_zero2 ||
 	    t->det_reserved_ft != EXT4_FT_DIR_CSUM)
 		return NULL;
@@ -425,13 +426,14 @@ static struct dx_countlimit *get_dx_countlimit(struct inode *inode,
 	struct ext4_dir_entry *dp;
 	struct dx_root_info *root;
 	int count_offset;
+	int blocksize = EXT4_BLOCK_SIZE(inode->i_sb);
+	unsigned int rlen = ext4_rec_len_from_disk(dirent->rec_len, blocksize);
 
-	if (le16_to_cpu(dirent->rec_len) == EXT4_BLOCK_SIZE(inode->i_sb))
+	if (rlen == blocksize)
 		count_offset = 8;
-	else if (le16_to_cpu(dirent->rec_len) == 12) {
+	else if (rlen == 12) {
 		dp = (struct ext4_dir_entry *)(((void *)dirent) + 12);
-		if (le16_to_cpu(dp->rec_len) !=
-		    EXT4_BLOCK_SIZE(inode->i_sb) - 12)
+		if (ext4_rec_len_from_disk(dp->rec_len, blocksize) != blocksize - 12)
 			return NULL;
 		root = (struct dx_root_info *)(((void *)dp + 12));
 		if (root->reserved_zero ||
@@ -1244,6 +1246,7 @@ static int dx_make_map(struct inode *dir, struct buffer_head *bh,
 	unsigned int buflen = bh->b_size;
 	char *base = bh->b_data;
 	struct dx_hash_info h = *hinfo;
+	int blocksize = EXT4_BLOCK_SIZE(dir->i_sb);
 
 	if (ext4_has_metadata_csum(dir->i_sb))
 		buflen -= sizeof(struct ext4_dir_entry_tail);
@@ -1257,11 +1260,12 @@ static int dx_make_map(struct inode *dir, struct buffer_head *bh,
 			map_tail--;
 			map_tail->hash = h.hash;
 			map_tail->offs = ((char *) de - base)>>2;
-			map_tail->size = le16_to_cpu(de->rec_len);
+			map_tail->size = ext4_rec_len_from_disk(de->rec_len,
+								blocksize);
 			count++;
 			cond_resched();
 		}
-		de = ext4_next_entry(de, dir->i_sb->s_blocksize);
+		de = ext4_next_entry(de, blocksize);
 	}
 	return count;
 }
-- 
2.27.0

[PATCH] ext4: fix rec_len verify error

[zhangshida]

From: Shida Zhang <zhangshida@kylinos.cn>

[ Upstream commit 7fda67e8c3ab6069f75888f67958a6d30454a9f6 ]

With the configuration PAGE_SIZE 64k and filesystem blocksize 64k,
a problem occurred when more than 13 million files were directly created
under a directory:

EXT4-fs error (device xx): ext4_dx_csum_set:492: inode #xxxx: comm xxxxx: dir seems corrupt?  Run e2fsck -D.
EXT4-fs error (device xx): ext4_dx_csum_verify:463: inode #xxxx: comm xxxxx: dir seems corrupt?  Run e2fsck -D.
EXT4-fs error (device xx): dx_probe:856: inode #xxxx: block 8188: comm xxxxx: Directory index failed checksum

When enough files are created, the fake_dirent->reclen will be 0xffff.
it doesn't equal to the blocksize 65536, i.e. 0x10000.

But it is not the same condition when blocksize equals to 4k.
when enough files are created, the fake_dirent->reclen will be 0x1000.
it equals to the blocksize 4k, i.e. 0x1000.

The problem seems to be related to the limitation of the 16-bit field
when the blocksize is set to 64k.
To address this, helpers like ext4_rec_len_{from,to}_disk has already
been introduced to complete the conversion between the encoded and the
plain form of rec_len.

So fix this one by using the helper, and all the other in this file too.

Cc: stable@kernel.org
Fixes: dbe89444042a ("ext4: Calculate and verify checksums for htree nodes")
Suggested-by: Andreas Dilger <adilger@dilger.ca>
Suggested-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Shida Zhang <zhangshida@kylinos.cn>
Reviewed-by: Andreas Dilger <adilger@dilger.ca>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Link: https://lore.kernel.org/r/20230803060938.1929759-1-zhangshida@kylinos.cn
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Shida Zhang <zhangshida@kylinos.cn>
---
 fs/ext4/namei.c | 26 +++++++++++++++-----------
 1 file changed, 15 insertions(+), 11 deletions(-)

diff --git a/fs/ext4/namei.c b/fs/ext4/namei.c
index 57c78a7a7425..a763216e1c15 100644
--- a/fs/ext4/namei.c
+++ b/fs/ext4/namei.c
@@ -321,17 +321,17 @@ static struct ext4_dir_entry_tail *get_dirent_tail(struct inode *inode,
 						   struct ext4_dir_entry *de)
 {
 	struct ext4_dir_entry_tail *t;
+	int blocksize = EXT4_BLOCK_SIZE(inode->i_sb);
 
 #ifdef PARANOID
 	struct ext4_dir_entry *d, *top;
 
 	d = de;
 	top = (struct ext4_dir_entry *)(((void *)de) +
-		(EXT4_BLOCK_SIZE(inode->i_sb) -
-		sizeof(struct ext4_dir_entry_tail)));
-	while (d < top && d->rec_len)
+		(blocksize - sizeof(struct ext4_dir_entry_tail)));
+	while (d < top && ext4_rec_len_from_disk(d->rec_len, blocksize))
 		d = (struct ext4_dir_entry *)(((void *)d) +
-		    le16_to_cpu(d->rec_len));
+		    ext4_rec_len_from_disk(d->rec_len, blocksize));
 
 	if (d != top)
 		return NULL;
@@ -342,7 +342,8 @@ static struct ext4_dir_entry_tail *get_dirent_tail(struct inode *inode,
 #endif
 
 	if (t->det_reserved_zero1 ||
-	    le16_to_cpu(t->det_rec_len) != sizeof(struct ext4_dir_entry_tail) ||
+	    (ext4_rec_len_from_disk(t->det_rec_len, blocksize) !=
+	     sizeof(struct ext4_dir_entry_tail)) ||
 	    t->det_reserved_zero2 ||
 	    t->det_reserved_ft != EXT4_FT_DIR_CSUM)
 		return NULL;
@@ -424,13 +425,14 @@ static struct dx_countlimit *get_dx_countlimit(struct inode *inode,
 	struct ext4_dir_entry *dp;
 	struct dx_root_info *root;
 	int count_offset;
+	int blocksize = EXT4_BLOCK_SIZE(inode->i_sb);
+	unsigned int rlen = ext4_rec_len_from_disk(dirent->rec_len, blocksize);
 
-	if (le16_to_cpu(dirent->rec_len) == EXT4_BLOCK_SIZE(inode->i_sb))
+	if (rlen == blocksize)
 		count_offset = 8;
-	else if (le16_to_cpu(dirent->rec_len) == 12) {
+	else if (rlen == 12) {
 		dp = (struct ext4_dir_entry *)(((void *)dirent) + 12);
-		if (le16_to_cpu(dp->rec_len) !=
-		    EXT4_BLOCK_SIZE(inode->i_sb) - 12)
+		if (ext4_rec_len_from_disk(dp->rec_len, blocksize) != blocksize - 12)
 			return NULL;
 		root = (struct dx_root_info *)(((void *)dp + 12));
 		if (root->reserved_zero ||
@@ -1243,6 +1245,7 @@ static int dx_make_map(struct inode *dir, struct buffer_head *bh,
 	unsigned int buflen = bh->b_size;
 	char *base = bh->b_data;
 	struct dx_hash_info h = *hinfo;
+	int blocksize = EXT4_BLOCK_SIZE(dir->i_sb);
 
 	if (ext4_has_metadata_csum(dir->i_sb))
 		buflen -= sizeof(struct ext4_dir_entry_tail);
@@ -1256,11 +1259,12 @@ static int dx_make_map(struct inode *dir, struct buffer_head *bh,
 			map_tail--;
 			map_tail->hash = h.hash;
 			map_tail->offs = ((char *) de - base)>>2;
-			map_tail->size = le16_to_cpu(de->rec_len);
+			map_tail->size = ext4_rec_len_from_disk(de->rec_len,
+								blocksize);
 			count++;
 			cond_resched();
 		}
-		de = ext4_next_entry(de, dir->i_sb->s_blocksize);
+		de = ext4_next_entry(de, blocksize);
 	}
 	return count;
 }
-- 
2.27.0

Re: [PATCH] ext4: fix rec_len verify error

[Greg KH]

On Fri, Sep 22, 2023 at 01:39:15PM +0800, zhangshida wrote:
> From: Shida Zhang <zhangshida@kylinos.cn>
> 
> [ Upstream commit 7fda67e8c3ab6069f75888f67958a6d30454a9f6 ]
> 
> With the configuration PAGE_SIZE 64k and filesystem blocksize 64k,
> a problem occurred when more than 13 million files were directly created
> under a directory:
> 
> EXT4-fs error (device xx): ext4_dx_csum_set:492: inode #xxxx: comm xxxxx: dir seems corrupt?  Run e2fsck -D.
> EXT4-fs error (device xx): ext4_dx_csum_verify:463: inode #xxxx: comm xxxxx: dir seems corrupt?  Run e2fsck -D.
> EXT4-fs error (device xx): dx_probe:856: inode #xxxx: block 8188: comm xxxxx: Directory index failed checksum
> 
> When enough files are created, the fake_dirent->reclen will be 0xffff.
> it doesn't equal to the blocksize 65536, i.e. 0x10000.
> 
> But it is not the same condition when blocksize equals to 4k.
> when enough files are created, the fake_dirent->reclen will be 0x1000.
> it equals to the blocksize 4k, i.e. 0x1000.
> 
> The problem seems to be related to the limitation of the 16-bit field
> when the blocksize is set to 64k.
> To address this, helpers like ext4_rec_len_{from,to}_disk has already
> been introduced to complete the conversion between the encoded and the
> plain form of rec_len.
> 
> So fix this one by using the helper, and all the other in this file too.
> 
> Cc: stable@kernel.org
> Fixes: dbe89444042a ("ext4: Calculate and verify checksums for htree nodes")
> Suggested-by: Andreas Dilger <adilger@dilger.ca>
> Suggested-by: Darrick J. Wong <djwong@kernel.org>
> Signed-off-by: Shida Zhang <zhangshida@kylinos.cn>
> Reviewed-by: Andreas Dilger <adilger@dilger.ca>
> Reviewed-by: Darrick J. Wong <djwong@kernel.org>
> Link: https://lore.kernel.org/r/20230803060938.1929759-1-zhangshida@kylinos.cn
> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
> Signed-off-by: Shida Zhang <zhangshida@kylinos.cn>
> ---
>  fs/ext4/namei.c | 26 +++++++++++++++-----------
>  1 file changed, 15 insertions(+), 11 deletions(-)

What stable tree(s) are you asking this to be backported to?

thanks,

greg k-h

Re: [PATCH] ext4: fix rec_len verify error

[Greg KH]

On Fri, Sep 22, 2023 at 10:54:58AM +0800, zhangshida wrote:
> From: Shida Zhang <zhangshida@kylinos.cn>
> 
> [ Upstream commit 7fda67e8c3ab6069f75888f67958a6d30454a9f6 ]
> 
> With the configuration PAGE_SIZE 64k and filesystem blocksize 64k,
> a problem occurred when more than 13 million files were directly created
> under a directory:
> 
> EXT4-fs error (device xx): ext4_dx_csum_set:492: inode #xxxx: comm xxxxx: dir seems corrupt?  Run e2fsck -D.
> EXT4-fs error (device xx): ext4_dx_csum_verify:463: inode #xxxx: comm xxxxx: dir seems corrupt?  Run e2fsck -D.
> EXT4-fs error (device xx): dx_probe:856: inode #xxxx: block 8188: comm xxxxx: Directory index failed checksum
> 
> When enough files are created, the fake_dirent->reclen will be 0xffff.
> it doesn't equal to the blocksize 65536, i.e. 0x10000.
> 
> But it is not the same condition when blocksize equals to 4k.
> when enough files are created, the fake_dirent->reclen will be 0x1000.
> it equals to the blocksize 4k, i.e. 0x1000.
> 
> The problem seems to be related to the limitation of the 16-bit field
> when the blocksize is set to 64k.
> To address this, helpers like ext4_rec_len_{from,to}_disk has already
> been introduced to complete the conversion between the encoded and the
> plain form of rec_len.
> 
> So fix this one by using the helper, and all the other in this file too.
> 
> Cc: stable@kernel.org
> Fixes: dbe89444042a ("ext4: Calculate and verify checksums for htree nodes")
> Suggested-by: Andreas Dilger <adilger@dilger.ca>
> Suggested-by: Darrick J. Wong <djwong@kernel.org>
> Signed-off-by: Shida Zhang <zhangshida@kylinos.cn>
> Reviewed-by: Andreas Dilger <adilger@dilger.ca>
> Reviewed-by: Darrick J. Wong <djwong@kernel.org>
> Link: https://lore.kernel.org/r/20230803060938.1929759-1-zhangshida@kylinos.cn
> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
> Signed-off-by: Shida Zhang <zhangshida@kylinos.cn>
> ---
>  fs/ext4/namei.c | 26 +++++++++++++++-----------
>  1 file changed, 15 insertions(+), 11 deletions(-)
> 

What stable kernel tree(s) are you asking for this to be applied to?

thanks,

greg k-h

Re: [PATCH] ext4: fix rec_len verify error

[Theodore Ts'o]

On Fri, Sep 22, 2023 at 11:23:59AM +0200, Greg KH wrote:
> 
> What stable tree(s) are you asking this to be backported to?

I assume that from the reply to message id
2023092057-company-unworried-210b@gregkh, this was intended for the
4.14 stable tree (since the automatic backport didn't apply).

Zhangshida, for future reference, when sending a patch for an LTS
kernel, please include the kernel version in the PATCH line,
e.g. "[PATCH 4.14.123]" or some such.  This saves everyone a lot of
time (including myself, since I need to filter out the LTS backports
to ext4 patchwork dashboard).

Thanks,

					- Ted

Re: [PATCH] ext4: fix rec_len verify error

[Stephen Zhang]

Greg KH <gregkh@linuxfoundation.org> 于2023年9月22日周五 17:27写道：
>
> On Fri, Sep 22, 2023 at 10:54:58AM +0800, zhangshida wrote:
> > From: Shida Zhang <zhangshida@kylinos.cn>
> >
> > [ Upstream commit 7fda67e8c3ab6069f75888f67958a6d30454a9f6 ]
> >
> > With the configuration PAGE_SIZE 64k and filesystem blocksize 64k,
> > a problem occurred when more than 13 million files were directly created
> > under a directory:
> >
> > EXT4-fs error (device xx): ext4_dx_csum_set:492: inode #xxxx: comm xxxxx: dir seems corrupt?  Run e2fsck -D.
> > EXT4-fs error (device xx): ext4_dx_csum_verify:463: inode #xxxx: comm xxxxx: dir seems corrupt?  Run e2fsck -D.
> > EXT4-fs error (device xx): dx_probe:856: inode #xxxx: block 8188: comm xxxxx: Directory index failed checksum
> >
> > When enough files are created, the fake_dirent->reclen will be 0xffff.
> > it doesn't equal to the blocksize 65536, i.e. 0x10000.
> >
> > But it is not the same condition when blocksize equals to 4k.
> > when enough files are created, the fake_dirent->reclen will be 0x1000.
> > it equals to the blocksize 4k, i.e. 0x1000.
> >
> > The problem seems to be related to the limitation of the 16-bit field
> > when the blocksize is set to 64k.
> > To address this, helpers like ext4_rec_len_{from,to}_disk has already
> > been introduced to complete the conversion between the encoded and the
> > plain form of rec_len.
> >
> > So fix this one by using the helper, and all the other in this file too.
> >
> > Cc: stable@kernel.org
> > Fixes: dbe89444042a ("ext4: Calculate and verify checksums for htree nodes")
> > Suggested-by: Andreas Dilger <adilger@dilger.ca>
> > Suggested-by: Darrick J. Wong <djwong@kernel.org>
> > Signed-off-by: Shida Zhang <zhangshida@kylinos.cn>
> > Reviewed-by: Andreas Dilger <adilger@dilger.ca>
> > Reviewed-by: Darrick J. Wong <djwong@kernel.org>
> > Link: https://lore.kernel.org/r/20230803060938.1929759-1-zhangshida@kylinos.cn
> > Signed-off-by: Theodore Ts'o <tytso@mit.edu>
> > Signed-off-by: Shida Zhang <zhangshida@kylinos.cn>
> > ---
> >  fs/ext4/namei.c | 26 +++++++++++++++-----------
> >  1 file changed, 15 insertions(+), 11 deletions(-)
> >
>
> What stable kernel tree(s) are you asking for this to be applied to?
>
> thanks,
>
> greg k-h

This one is intended for 4.14.y.
And the other one from zhangshida@kylinos.cn is for 4.19.y.

Apologies for this confusion. It appears that the '--subject-prefix' option
of the 'git send-email' command does not work with the local patch file.

BTW, I forgot to CC my Gmail address in another thread,
so I reply here only.

Best regards,
Shida

Re: [PATCH] ext4: fix rec_len verify error

[Theodore Ts'o]

On Sat, Sep 23, 2023 at 05:41:19PM +0800, Stephen Zhang wrote:
> Apologies for this confusion. It appears that the '--subject-prefix' option
> of the 'git send-email' command does not work with the local patch file.

Stephen,

The --subject-prefix option applies to "git format-patch" when the
local patch file is generated, as opposed to "git send-email".  So my
general workflow is to run "rm -rf /tmp/p ; git format-patch -o /tmp/p
..."  and then examine the files in /tmp/p, and then if they look
good, run "git send-email /tmp/p/*".

I suspect it will be easier for Greg if you were to simply regenerate
the patches with the proper subject prefix, and then resend them,
since he has automation tools that can handle parsing the subject
line, which scripts can do much more easily than to disentangling the
"In-Reply-To" header to identify e-mail chains, and then parsing
human/natural language to figure out which git tree the patches should
be applied to.  :-)

Cheers,

					- Ted

Re: [PATCH] ext4: fix rec_len verify error

[Greg KH]

On Sat, Sep 23, 2023 at 10:47:29AM -0400, Theodore Ts'o wrote:
> On Sat, Sep 23, 2023 at 05:41:19PM +0800, Stephen Zhang wrote:
> > Apologies for this confusion. It appears that the '--subject-prefix' option
> > of the 'git send-email' command does not work with the local patch file.
> 
> Stephen,
> 
> The --subject-prefix option applies to "git format-patch" when the
> local patch file is generated, as opposed to "git send-email".  So my
> general workflow is to run "rm -rf /tmp/p ; git format-patch -o /tmp/p
> ..."  and then examine the files in /tmp/p, and then if they look
> good, run "git send-email /tmp/p/*".
> 
> I suspect it will be easier for Greg if you were to simply regenerate
> the patches with the proper subject prefix, and then resend them,
> since he has automation tools that can handle parsing the subject
> line, which scripts can do much more easily than to disentangling the
> "In-Reply-To" header to identify e-mail chains, and then parsing
> human/natural language to figure out which git tree the patches should
> be applied to.  :-)

Just a hint, I can usually NOT see the In-Reply-To headers at all, as
the email it was in response to is long gone from my system.

Which is why, the description of how to fix up a patch for the stable
tree that has failed to apply there, tells you how to do this in a way
that will show the proper version number.

If only anyone would actually read the emails we sent with the helpful
text, here's one example for a DRM patch that failed to apply:

	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-6.1.y
	git checkout FETCH_HEAD
	git cherry-pick -x ec5fa9fcdeca69edf7dab5ca3b2e0ceb1c08fe9a
	# <resolve conflicts, build, test, etc.>
	git commit -s
	git send-email --to '<stable@vger.kernel.org>' --in-reply-to '2023092029-banter-truth-cf72@gregkh' --subject-prefix 'PATCH 6.1.y' HEAD^..

thanks,

greg k-h

[PATCH 4.19.y] ext4: fix rec_len verify error

[zhangshida]

From: Shida Zhang <zhangshida@kylinos.cn>

With the configuration PAGE_SIZE 64k and filesystem blocksize 64k,
a problem occurred when more than 13 million files were directly created
under a directory:

EXT4-fs error (device xx): ext4_dx_csum_set:492: inode #xxxx: comm xxxxx: dir seems corrupt?  Run e2fsck -D.
EXT4-fs error (device xx): ext4_dx_csum_verify:463: inode #xxxx: comm xxxxx: dir seems corrupt?  Run e2fsck -D.
EXT4-fs error (device xx): dx_probe:856: inode #xxxx: block 8188: comm xxxxx: Directory index failed checksum

When enough files are created, the fake_dirent->reclen will be 0xffff.
it doesn't equal to the blocksize 65536, i.e. 0x10000.

But it is not the same condition when blocksize equals to 4k.
when enough files are created, the fake_dirent->reclen will be 0x1000.
it equals to the blocksize 4k, i.e. 0x1000.

The problem seems to be related to the limitation of the 16-bit field
when the blocksize is set to 64k.
To address this, helpers like ext4_rec_len_{from,to}_disk has already
been introduced to complete the conversion between the encoded and the
plain form of rec_len.

So fix this one by using the helper, and all the other in this file too.

Cc: stable@kernel.org
Fixes: dbe89444042a ("ext4: Calculate and verify checksums for htree nodes")
Suggested-by: Andreas Dilger <adilger@dilger.ca>
Suggested-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Shida Zhang <zhangshida@kylinos.cn>
Reviewed-by: Andreas Dilger <adilger@dilger.ca>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Link: https://lore.kernel.org/r/20230803060938.1929759-1-zhangshida@kylinos.cn
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
(cherry picked from commit 7fda67e8c3ab6069f75888f67958a6d30454a9f6)
Signed-off-by: Shida Zhang <zhangshida@kylinos.cn>
---
 fs/ext4/namei.c | 26 +++++++++++++++-----------
 1 file changed, 15 insertions(+), 11 deletions(-)

diff --git a/fs/ext4/namei.c b/fs/ext4/namei.c
index db9bba3473b5..93d392576c12 100644
--- a/fs/ext4/namei.c
+++ b/fs/ext4/namei.c
@@ -322,17 +322,17 @@ static struct ext4_dir_entry_tail *get_dirent_tail(struct inode *inode,
 						   struct ext4_dir_entry *de)
 {
 	struct ext4_dir_entry_tail *t;
+	int blocksize = EXT4_BLOCK_SIZE(inode->i_sb);
 
 #ifdef PARANOID
 	struct ext4_dir_entry *d, *top;
 
 	d = de;
 	top = (struct ext4_dir_entry *)(((void *)de) +
-		(EXT4_BLOCK_SIZE(inode->i_sb) -
-		sizeof(struct ext4_dir_entry_tail)));
-	while (d < top && d->rec_len)
+		(blocksize - sizeof(struct ext4_dir_entry_tail)));
+	while (d < top && ext4_rec_len_from_disk(d->rec_len, blocksize))
 		d = (struct ext4_dir_entry *)(((void *)d) +
-		    le16_to_cpu(d->rec_len));
+		    ext4_rec_len_from_disk(d->rec_len, blocksize));
 
 	if (d != top)
 		return NULL;
@@ -343,7 +343,8 @@ static struct ext4_dir_entry_tail *get_dirent_tail(struct inode *inode,
 #endif
 
 	if (t->det_reserved_zero1 ||
-	    le16_to_cpu(t->det_rec_len) != sizeof(struct ext4_dir_entry_tail) ||
+	    (ext4_rec_len_from_disk(t->det_rec_len, blocksize) !=
+	     sizeof(struct ext4_dir_entry_tail)) ||
 	    t->det_reserved_zero2 ||
 	    t->det_reserved_ft != EXT4_FT_DIR_CSUM)
 		return NULL;
@@ -425,13 +426,14 @@ static struct dx_countlimit *get_dx_countlimit(struct inode *inode,
 	struct ext4_dir_entry *dp;
 	struct dx_root_info *root;
 	int count_offset;
+	int blocksize = EXT4_BLOCK_SIZE(inode->i_sb);
+	unsigned int rlen = ext4_rec_len_from_disk(dirent->rec_len, blocksize);
 
-	if (le16_to_cpu(dirent->rec_len) == EXT4_BLOCK_SIZE(inode->i_sb))
+	if (rlen == blocksize)
 		count_offset = 8;
-	else if (le16_to_cpu(dirent->rec_len) == 12) {
+	else if (rlen == 12) {
 		dp = (struct ext4_dir_entry *)(((void *)dirent) + 12);
-		if (le16_to_cpu(dp->rec_len) !=
-		    EXT4_BLOCK_SIZE(inode->i_sb) - 12)
+		if (ext4_rec_len_from_disk(dp->rec_len, blocksize) != blocksize - 12)
 			return NULL;
 		root = (struct dx_root_info *)(((void *)dp + 12));
 		if (root->reserved_zero ||
@@ -1244,6 +1246,7 @@ static int dx_make_map(struct inode *dir, struct buffer_head *bh,
 	unsigned int buflen = bh->b_size;
 	char *base = bh->b_data;
 	struct dx_hash_info h = *hinfo;
+	int blocksize = EXT4_BLOCK_SIZE(dir->i_sb);
 
 	if (ext4_has_metadata_csum(dir->i_sb))
 		buflen -= sizeof(struct ext4_dir_entry_tail);
@@ -1257,11 +1260,12 @@ static int dx_make_map(struct inode *dir, struct buffer_head *bh,
 			map_tail--;
 			map_tail->hash = h.hash;
 			map_tail->offs = ((char *) de - base)>>2;
-			map_tail->size = le16_to_cpu(de->rec_len);
+			map_tail->size = ext4_rec_len_from_disk(de->rec_len,
+								blocksize);
 			count++;
 			cond_resched();
 		}
-		de = ext4_next_entry(de, dir->i_sb->s_blocksize);
+		de = ext4_next_entry(de, blocksize);
 	}
 	return count;
 }
-- 
2.27.0

Re: [PATCH 4.19.y] ext4: fix rec_len verify error

[Stephen Zhang]

zhangshida <starzhangzsd@gmail.com> 于2023年9月24日周日 10:27写道：
>
> From: Shida Zhang <zhangshida@kylinos.cn>
>
> With the configuration PAGE_SIZE 64k and filesystem blocksize 64k,
> a problem occurred when more than 13 million files were directly created
> under a directory:
>
> EXT4-fs error (device xx): ext4_dx_csum_set:492: inode #xxxx: comm xxxxx: dir seems corrupt?  Run e2fsck -D.
> EXT4-fs error (device xx): ext4_dx_csum_verify:463: inode #xxxx: comm xxxxx: dir seems corrupt?  Run e2fsck -D.
> EXT4-fs error (device xx): dx_probe:856: inode #xxxx: block 8188: comm xxxxx: Directory index failed checksum
>
> When enough files are created, the fake_dirent->reclen will be 0xffff.
> it doesn't equal to the blocksize 65536, i.e. 0x10000.
>
> But it is not the same condition when blocksize equals to 4k.
> when enough files are created, the fake_dirent->reclen will be 0x1000.
> it equals to the blocksize 4k, i.e. 0x1000.
>
> The problem seems to be related to the limitation of the 16-bit field
> when the blocksize is set to 64k.
> To address this, helpers like ext4_rec_len_{from,to}_disk has already
> been introduced to complete the conversion between the encoded and the
> plain form of rec_len.
>
> So fix this one by using the helper, and all the other in this file too.
>
> Cc: stable@kernel.org
> Fixes: dbe89444042a ("ext4: Calculate and verify checksums for htree nodes")
> Suggested-by: Andreas Dilger <adilger@dilger.ca>
> Suggested-by: Darrick J. Wong <djwong@kernel.org>
> Signed-off-by: Shida Zhang <zhangshida@kylinos.cn>
> Reviewed-by: Andreas Dilger <adilger@dilger.ca>
> Reviewed-by: Darrick J. Wong <djwong@kernel.org>
> Link: https://lore.kernel.org/r/20230803060938.1929759-1-zhangshida@kylinos.cn
> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
> (cherry picked from commit 7fda67e8c3ab6069f75888f67958a6d30454a9f6)

Oh no, I forgot to change that line to [Upstream commit ...] T_T
Will resend.

Best regards,
Shida.

> Signed-off-by: Shida Zhang <zhangshida@kylinos.cn>
> ---
>  fs/ext4/namei.c | 26 +++++++++++++++-----------
>  1 file changed, 15 insertions(+), 11 deletions(-)
>
> diff --git a/fs/ext4/namei.c b/fs/ext4/namei.c
> index db9bba3473b5..93d392576c12 100644
> --- a/fs/ext4/namei.c
> +++ b/fs/ext4/namei.c
> @@ -322,17 +322,17 @@ static struct ext4_dir_entry_tail *get_dirent_tail(struct inode *inode,
>                                                    struct ext4_dir_entry *de)
>  {
>         struct ext4_dir_entry_tail *t;
> +       int blocksize = EXT4_BLOCK_SIZE(inode->i_sb);
>
>  #ifdef PARANOID
>         struct ext4_dir_entry *d, *top;
>
>         d = de;
>         top = (struct ext4_dir_entry *)(((void *)de) +
> -               (EXT4_BLOCK_SIZE(inode->i_sb) -
> -               sizeof(struct ext4_dir_entry_tail)));
> -       while (d < top && d->rec_len)
> +               (blocksize - sizeof(struct ext4_dir_entry_tail)));
> +       while (d < top && ext4_rec_len_from_disk(d->rec_len, blocksize))
>                 d = (struct ext4_dir_entry *)(((void *)d) +
> -                   le16_to_cpu(d->rec_len));
> +                   ext4_rec_len_from_disk(d->rec_len, blocksize));
>
>         if (d != top)
>                 return NULL;
> @@ -343,7 +343,8 @@ static struct ext4_dir_entry_tail *get_dirent_tail(struct inode *inode,
>  #endif
>
>         if (t->det_reserved_zero1 ||
> -           le16_to_cpu(t->det_rec_len) != sizeof(struct ext4_dir_entry_tail) ||
> +           (ext4_rec_len_from_disk(t->det_rec_len, blocksize) !=
> +            sizeof(struct ext4_dir_entry_tail)) ||
>             t->det_reserved_zero2 ||
>             t->det_reserved_ft != EXT4_FT_DIR_CSUM)
>                 return NULL;
> @@ -425,13 +426,14 @@ static struct dx_countlimit *get_dx_countlimit(struct inode *inode,
>         struct ext4_dir_entry *dp;
>         struct dx_root_info *root;
>         int count_offset;
> +       int blocksize = EXT4_BLOCK_SIZE(inode->i_sb);
> +       unsigned int rlen = ext4_rec_len_from_disk(dirent->rec_len, blocksize);
>
> -       if (le16_to_cpu(dirent->rec_len) == EXT4_BLOCK_SIZE(inode->i_sb))
> +       if (rlen == blocksize)
>                 count_offset = 8;
> -       else if (le16_to_cpu(dirent->rec_len) == 12) {
> +       else if (rlen == 12) {
>                 dp = (struct ext4_dir_entry *)(((void *)dirent) + 12);
> -               if (le16_to_cpu(dp->rec_len) !=
> -                   EXT4_BLOCK_SIZE(inode->i_sb) - 12)
> +               if (ext4_rec_len_from_disk(dp->rec_len, blocksize) != blocksize - 12)
>                         return NULL;
>                 root = (struct dx_root_info *)(((void *)dp + 12));
>                 if (root->reserved_zero ||
> @@ -1244,6 +1246,7 @@ static int dx_make_map(struct inode *dir, struct buffer_head *bh,
>         unsigned int buflen = bh->b_size;
>         char *base = bh->b_data;
>         struct dx_hash_info h = *hinfo;
> +       int blocksize = EXT4_BLOCK_SIZE(dir->i_sb);
>
>         if (ext4_has_metadata_csum(dir->i_sb))
>                 buflen -= sizeof(struct ext4_dir_entry_tail);
> @@ -1257,11 +1260,12 @@ static int dx_make_map(struct inode *dir, struct buffer_head *bh,
>                         map_tail--;
>                         map_tail->hash = h.hash;
>                         map_tail->offs = ((char *) de - base)>>2;
> -                       map_tail->size = le16_to_cpu(de->rec_len);
> +                       map_tail->size = ext4_rec_len_from_disk(de->rec_len,
> +                                                               blocksize);
>                         count++;
>                         cond_resched();
>                 }
> -               de = ext4_next_entry(de, dir->i_sb->s_blocksize);
> +               de = ext4_next_entry(de, blocksize);
>         }
>         return count;
>  }
> --
> 2.27.0
>

[PATCH 4.19.y] ext4: fix rec_len verify error

[zhangshida]

From: Shida Zhang <zhangshida@kylinos.cn>

[ Upstream commit 7fda67e8c3ab6069f75888f67958a6d30454a9f6 ]

With the configuration PAGE_SIZE 64k and filesystem blocksize 64k,
a problem occurred when more than 13 million files were directly created
under a directory:

EXT4-fs error (device xx): ext4_dx_csum_set:492: inode #xxxx: comm xxxxx: dir seems corrupt?  Run e2fsck -D.
EXT4-fs error (device xx): ext4_dx_csum_verify:463: inode #xxxx: comm xxxxx: dir seems corrupt?  Run e2fsck -D.
EXT4-fs error (device xx): dx_probe:856: inode #xxxx: block 8188: comm xxxxx: Directory index failed checksum

When enough files are created, the fake_dirent->reclen will be 0xffff.
it doesn't equal to the blocksize 65536, i.e. 0x10000.

But it is not the same condition when blocksize equals to 4k.
when enough files are created, the fake_dirent->reclen will be 0x1000.
it equals to the blocksize 4k, i.e. 0x1000.

The problem seems to be related to the limitation of the 16-bit field
when the blocksize is set to 64k.
To address this, helpers like ext4_rec_len_{from,to}_disk has already
been introduced to complete the conversion between the encoded and the
plain form of rec_len.

So fix this one by using the helper, and all the other in this file too.

Cc: stable@kernel.org
Fixes: dbe89444042a ("ext4: Calculate and verify checksums for htree nodes")
Suggested-by: Andreas Dilger <adilger@dilger.ca>
Suggested-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Shida Zhang <zhangshida@kylinos.cn>
Reviewed-by: Andreas Dilger <adilger@dilger.ca>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Link: https://lore.kernel.org/r/20230803060938.1929759-1-zhangshida@kylinos.cn
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Shida Zhang <zhangshida@kylinos.cn>
---
 fs/ext4/namei.c | 26 +++++++++++++++-----------
 1 file changed, 15 insertions(+), 11 deletions(-)

diff --git a/fs/ext4/namei.c b/fs/ext4/namei.c
index db9bba3473b5..93d392576c12 100644
--- a/fs/ext4/namei.c
+++ b/fs/ext4/namei.c
@@ -322,17 +322,17 @@ static struct ext4_dir_entry_tail *get_dirent_tail(struct inode *inode,
 						   struct ext4_dir_entry *de)
 {
 	struct ext4_dir_entry_tail *t;
+	int blocksize = EXT4_BLOCK_SIZE(inode->i_sb);
 
 #ifdef PARANOID
 	struct ext4_dir_entry *d, *top;
 
 	d = de;
 	top = (struct ext4_dir_entry *)(((void *)de) +
-		(EXT4_BLOCK_SIZE(inode->i_sb) -
-		sizeof(struct ext4_dir_entry_tail)));
-	while (d < top && d->rec_len)
+		(blocksize - sizeof(struct ext4_dir_entry_tail)));
+	while (d < top && ext4_rec_len_from_disk(d->rec_len, blocksize))
 		d = (struct ext4_dir_entry *)(((void *)d) +
-		    le16_to_cpu(d->rec_len));
+		    ext4_rec_len_from_disk(d->rec_len, blocksize));
 
 	if (d != top)
 		return NULL;
@@ -343,7 +343,8 @@ static struct ext4_dir_entry_tail *get_dirent_tail(struct inode *inode,
 #endif
 
 	if (t->det_reserved_zero1 ||
-	    le16_to_cpu(t->det_rec_len) != sizeof(struct ext4_dir_entry_tail) ||
+	    (ext4_rec_len_from_disk(t->det_rec_len, blocksize) !=
+	     sizeof(struct ext4_dir_entry_tail)) ||
 	    t->det_reserved_zero2 ||
 	    t->det_reserved_ft != EXT4_FT_DIR_CSUM)
 		return NULL;
@@ -425,13 +426,14 @@ static struct dx_countlimit *get_dx_countlimit(struct inode *inode,
 	struct ext4_dir_entry *dp;
 	struct dx_root_info *root;
 	int count_offset;
+	int blocksize = EXT4_BLOCK_SIZE(inode->i_sb);
+	unsigned int rlen = ext4_rec_len_from_disk(dirent->rec_len, blocksize);
 
-	if (le16_to_cpu(dirent->rec_len) == EXT4_BLOCK_SIZE(inode->i_sb))
+	if (rlen == blocksize)
 		count_offset = 8;
-	else if (le16_to_cpu(dirent->rec_len) == 12) {
+	else if (rlen == 12) {
 		dp = (struct ext4_dir_entry *)(((void *)dirent) + 12);
-		if (le16_to_cpu(dp->rec_len) !=
-		    EXT4_BLOCK_SIZE(inode->i_sb) - 12)
+		if (ext4_rec_len_from_disk(dp->rec_len, blocksize) != blocksize - 12)
 			return NULL;
 		root = (struct dx_root_info *)(((void *)dp + 12));
 		if (root->reserved_zero ||
@@ -1244,6 +1246,7 @@ static int dx_make_map(struct inode *dir, struct buffer_head *bh,
 	unsigned int buflen = bh->b_size;
 	char *base = bh->b_data;
 	struct dx_hash_info h = *hinfo;
+	int blocksize = EXT4_BLOCK_SIZE(dir->i_sb);
 
 	if (ext4_has_metadata_csum(dir->i_sb))
 		buflen -= sizeof(struct ext4_dir_entry_tail);
@@ -1257,11 +1260,12 @@ static int dx_make_map(struct inode *dir, struct buffer_head *bh,
 			map_tail--;
 			map_tail->hash = h.hash;
 			map_tail->offs = ((char *) de - base)>>2;
-			map_tail->size = le16_to_cpu(de->rec_len);
+			map_tail->size = ext4_rec_len_from_disk(de->rec_len,
+								blocksize);
 			count++;
 			cond_resched();
 		}
-		de = ext4_next_entry(de, dir->i_sb->s_blocksize);
+		de = ext4_next_entry(de, blocksize);
 	}
 	return count;
 }
-- 
2.27.0