Commit e77762e8 authored by Hongbo Li's avatar Hongbo Li Committed by Gao Xiang
Browse files

erofs: using domain_id in the safer way 



Either the existing fscache usecase or the upcoming page
cache sharing case, the `domain_id` should be protected as
sensitive information, so we use the safer helpers to allocate,
free and display domain_id.

Signed-off-by: default avatarHongbo Li <lihongbo22@huawei.com>
Reviewed-by: default avatarGao Xiang <hsiangkao@linux.alibaba.com>
Signed-off-by: default avatarGao Xiang <hsiangkao@linux.alibaba.com>
parent 78331814

Documentation/filesystems/erofs.rst

+3 −2
Original line number Diff line number Diff line
@@ -128,8 +128,9 @@ device=%s Specify a path to an extra device to be used together. 
directio               (For file-backed mounts) Use direct I/O to access backing

                       files, and asynchronous I/O will be enabled if supported.

fsid=%s                Specify a filesystem image ID for Fscache back-end.

domain_id=%s           Specify a domain ID in fscache mode so that different images

                       with the same blobs under a given domain ID can share storage.

domain_id=%s           Specify a trusted domain ID for fscache mode so that

                       different images with the same blobs, identified by blob IDs,

                       can share storage within the same trusted domain.

fsoffset=%llu          Specify block-aligned filesystem offset for the primary device.

===================    =========================================================

fs/erofs/fscache.c

+2 −2
Original line number Diff line number Diff line
@@ -379,7 +379,7 @@ static void erofs_fscache_domain_put(struct erofs_domain *domain) 
		}

		fscache_relinquish_volume(domain->volume, NULL, false);

		mutex_unlock(&erofs_domain_list_lock);

		kfree(domain->domain_id);

		kfree_sensitive(domain->domain_id);

		kfree(domain);

		return;

	}
@@ -446,7 +446,7 @@ static int erofs_fscache_init_domain(struct super_block *sb) 
	sbi->domain = domain;

	return 0;

out:

	kfree(domain->domain_id);

	kfree_sensitive(domain->domain_id);

	kfree(domain);

	return err;

}

fs/erofs/super.c

+4 −6
Original line number Diff line number Diff line
@@ -527,10 +527,8 @@ static int erofs_fc_parse_param(struct fs_context *fc, 
			return -ENOMEM;

		break;

	case Opt_domain_id:

		kfree(sbi->domain_id);

		sbi->domain_id = kstrdup(param->string, GFP_KERNEL);

		if (!sbi->domain_id)

			return -ENOMEM;

		kfree_sensitive(sbi->domain_id);

		sbi->domain_id = no_free_ptr(param->string);

		break;

#else

	case Opt_fsid:
@@ -626,7 +624,7 @@ static void erofs_set_sysfs_name(struct super_block *sb) 
{

	struct erofs_sb_info *sbi = EROFS_SB(sb);



	if (sbi->domain_id)

	if (sbi->domain_id && sbi->fsid)

		super_set_sysfs_name_generic(sb, "%s,%s", sbi->domain_id,

					     sbi->fsid);

	else if (sbi->fsid)
@@ -861,7 +859,7 @@ static void erofs_sb_free(struct erofs_sb_info *sbi) 
{

	erofs_free_dev_context(sbi->devs);

	kfree(sbi->fsid);

	kfree(sbi->domain_id);

	kfree_sensitive(sbi->domain_id);

	if (sbi->dif0.file)

		fput(sbi->dif0.file);

	kfree(sbi->volume_name);