ext4: align max orphan file size with e2fsprogs limit

[PATCH] ext4: align max orphan file size with e2fsprogs limit

Posted by libaokun@huaweicloud.com 1 week, 4 days ago

From: Baokun Li <libaokun1@huawei.com>

Kernel commit 0a6ce20c1564 ("ext4: verify orphan file size is not too big")
limits the maximum supported orphan file size to 8 << 20.

However, in e2fsprogs, the orphan file size is set to 32–512 filesystem
blocks when creating a filesystem.

With 64k block size, formatting an ext4 fs >32G gives an orphan file bigger
than the kernel allows, so mount prints an error and fails:

    EXT4-fs (vdb): orphan file too big: 8650752
    EXT4-fs (vdb): mount failed

To prevent this issue and allow previously created 64KB filesystems to
mount, we updates the maximum allowed orphan file size in the kernel to
512 filesystem blocks.

Fixes: 0a6ce20c1564 ("ext4: verify orphan file size is not too big")
Signed-off-by: Baokun Li <libaokun1@huawei.com>
---
 fs/ext4/orphan.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/fs/ext4/orphan.c b/fs/ext4/orphan.c
index 82d5e7501455..fb57bba0d19d 100644
--- a/fs/ext4/orphan.c
+++ b/fs/ext4/orphan.c
@@ -8,6 +8,8 @@
 #include "ext4.h"
 #include "ext4_jbd2.h"
 
+#define EXT4_MAX_ORPHAN_FILE_BLOCKS 512
+
 static int ext4_orphan_file_add(handle_t *handle, struct inode *inode)
 {
 	int i, j, start;
@@ -588,7 +590,7 @@ int ext4_init_orphan_info(struct super_block *sb)
 	 * consuming absurd amounts of memory when pinning blocks of orphan
 	 * file in memory.
 	 */
-	if (inode->i_size > 8 << 20) {
+	if (inode->i_size > (EXT4_MAX_ORPHAN_FILE_BLOCKS << inode->i_blkbits)) {
 		ext4_msg(sb, KERN_ERR, "orphan file too big: %llu",
 			 (unsigned long long)inode->i_size);
 		ret = -EFSCORRUPTED;
-- 
2.46.1

Re: [PATCH] ext4: align max orphan file size with e2fsprogs limit

Posted by Theodore Ts'o 9 hours ago

On Thu, 20 Nov 2025 21:42:33 +0800, libaokun@huaweicloud.com wrote:
> Kernel commit 0a6ce20c1564 ("ext4: verify orphan file size is not too big")
> limits the maximum supported orphan file size to 8 << 20.
> 
> However, in e2fsprogs, the orphan file size is set to 32–512 filesystem
> blocks when creating a filesystem.
> 
> With 64k block size, formatting an ext4 fs >32G gives an orphan file bigger
> than the kernel allows, so mount prints an error and fails:
> 
> [...]

Applied, thanks!

[1/1] ext4: align max orphan file size with e2fsprogs limit
      commit: 7c11c56eb32eae96893eebafdbe3decadefe88ad

Best regards,
-- 
Theodore Ts'o <tytso@mit.edu>

Re: [PATCH] ext4: align max orphan file size with e2fsprogs limit

Posted by Zhang Yi 4 days, 17 hours ago

On 11/20/2025 9:42 PM, libaokun@huaweicloud.com wrote:
> From: Baokun Li <libaokun1@huawei.com>
> 
> Kernel commit 0a6ce20c1564 ("ext4: verify orphan file size is not too big")
> limits the maximum supported orphan file size to 8 << 20.
> 
> However, in e2fsprogs, the orphan file size is set to 32–512 filesystem
> blocks when creating a filesystem.
> 
> With 64k block size, formatting an ext4 fs >32G gives an orphan file bigger
> than the kernel allows, so mount prints an error and fails:
> 
>     EXT4-fs (vdb): orphan file too big: 8650752
>     EXT4-fs (vdb): mount failed
> 
> To prevent this issue and allow previously created 64KB filesystems to
> mount, we updates the maximum allowed orphan file size in the kernel to
> 512 filesystem blocks.
> 
> Fixes: 0a6ce20c1564 ("ext4: verify orphan file size is not too big")
> Signed-off-by: Baokun Li <libaokun1@huawei.com>

Looks good to me.

Reviewed-by: Zhang Yi <yi.zhang@huawei.com>

> ---
>  fs/ext4/orphan.c | 4 +++-
>  1 file changed, 3 insertions(+), 1 deletion(-)
> 
> diff --git a/fs/ext4/orphan.c b/fs/ext4/orphan.c
> index 82d5e7501455..fb57bba0d19d 100644
> --- a/fs/ext4/orphan.c
> +++ b/fs/ext4/orphan.c
> @@ -8,6 +8,8 @@
>  #include "ext4.h"
>  #include "ext4_jbd2.h"
>  
> +#define EXT4_MAX_ORPHAN_FILE_BLOCKS 512
> +
>  static int ext4_orphan_file_add(handle_t *handle, struct inode *inode)
>  {
>  	int i, j, start;
> @@ -588,7 +590,7 @@ int ext4_init_orphan_info(struct super_block *sb)
>  	 * consuming absurd amounts of memory when pinning blocks of orphan
>  	 * file in memory.
>  	 */
> -	if (inode->i_size > 8 << 20) {
> +	if (inode->i_size > (EXT4_MAX_ORPHAN_FILE_BLOCKS << inode->i_blkbits)) {
>  		ext4_msg(sb, KERN_ERR, "orphan file too big: %llu",
>  			 (unsigned long long)inode->i_size);
>  		ret = -EFSCORRUPTED;

Re: [PATCH] ext4: align max orphan file size with e2fsprogs limit

Posted by Jan Kara 6 days, 14 hours ago

On Thu 20-11-25 21:42:33, libaokun@huaweicloud.com wrote:
> From: Baokun Li <libaokun1@huawei.com>
> 
> Kernel commit 0a6ce20c1564 ("ext4: verify orphan file size is not too big")
> limits the maximum supported orphan file size to 8 << 20.
> 
> However, in e2fsprogs, the orphan file size is set to 32–512 filesystem
> blocks when creating a filesystem.
> 
> With 64k block size, formatting an ext4 fs >32G gives an orphan file bigger
> than the kernel allows, so mount prints an error and fails:
> 
>     EXT4-fs (vdb): orphan file too big: 8650752
>     EXT4-fs (vdb): mount failed
> 
> To prevent this issue and allow previously created 64KB filesystems to
> mount, we updates the maximum allowed orphan file size in the kernel to
> 512 filesystem blocks.
> 
> Fixes: 0a6ce20c1564 ("ext4: verify orphan file size is not too big")
> Signed-off-by: Baokun Li <libaokun1@huawei.com>

OK, makes sense. Feel free to add:

Reviewed-by: Jan Kara <jack@suse.cz>

								Honza

> ---
>  fs/ext4/orphan.c | 4 +++-
>  1 file changed, 3 insertions(+), 1 deletion(-)
> 
> diff --git a/fs/ext4/orphan.c b/fs/ext4/orphan.c
> index 82d5e7501455..fb57bba0d19d 100644
> --- a/fs/ext4/orphan.c
> +++ b/fs/ext4/orphan.c
> @@ -8,6 +8,8 @@
>  #include "ext4.h"
>  #include "ext4_jbd2.h"
>  
> +#define EXT4_MAX_ORPHAN_FILE_BLOCKS 512
> +
>  static int ext4_orphan_file_add(handle_t *handle, struct inode *inode)
>  {
>  	int i, j, start;
> @@ -588,7 +590,7 @@ int ext4_init_orphan_info(struct super_block *sb)
>  	 * consuming absurd amounts of memory when pinning blocks of orphan
>  	 * file in memory.
>  	 */
> -	if (inode->i_size > 8 << 20) {
> +	if (inode->i_size > (EXT4_MAX_ORPHAN_FILE_BLOCKS << inode->i_blkbits)) {
>  		ext4_msg(sb, KERN_ERR, "orphan file too big: %llu",
>  			 (unsigned long long)inode->i_size);
>  		ret = -EFSCORRUPTED;
> -- 
> 2.46.1
> 
-- 
Jan Kara <jack@suse.com>
SUSE Labs, CR