Let's add .get_acl() to read the file's acl from its xattrs
to make POSIX ACL usable.
Here is the on-disk detail,
fullname: system.posix_acl_access
struct erofs_xattr_entry:
.e_name_len = 0
.e_name_index = EROFS_XATTR_INDEX_POSIX_ACL_ACCESS (2)
fullname: system.posix_acl_default
struct erofs_xattr_entry:
.e_name_len = 0
.e_name_index = EROFS_XATTR_INDEX_POSIX_ACL_DEFAULT (3)
Reviewed-by: Chao Yu <yuchao0@xxxxxxxxxx>
Signed-off-by: Gao Xiang <gaoxiang25@xxxxxxxxxx>
---
change log v4:
- leave kmalloc and wait the conclusion of fault injection
pointed out by Dan Carpenter;
change log v3:
- kvmalloc -> erofs_kmalloc suggested by Chao;
- update SB_POSIXACL for the remount case as well;
change log v2:
- add the missing SB_POSIXACL flag;
- fix the on-disk detail, use .e_name_len == 0 and proper prefix value;
- tested ok with xattr enabled erofs_mkfs;
.../erofs/Documentation/filesystems/erofs.txt | 2 ++
drivers/staging/erofs/inode.c | 3 ++
drivers/staging/erofs/namei.c | 1 +
drivers/staging/erofs/super.c | 10 ++++++
drivers/staging/erofs/xattr.c | 37 ++++++++++++++++++++++
drivers/staging/erofs/xattr.h | 6 ++++
6 files changed, 59 insertions(+)
diff --git a/drivers/staging/erofs/Documentation/filesystems/erofs.txt b/drivers/staging/erofs/Documentation/filesystems/erofs.txt
index 803988d74c21..961ec4da7705 100644
--- a/drivers/staging/erofs/Documentation/filesystems/erofs.txt
+++ b/drivers/staging/erofs/Documentation/filesystems/erofs.txt
@@ -36,6 +36,8 @@ Here is the main features of EROFS:
- Support xattr inline and tail-end data inline for all files;
+ - Support POSIX.1e ACLs by using xattrs;
+
- Support transparent file compression as an option:
LZ4 algorithm with 4 KB fixed-output compression for high performance;
diff --git a/drivers/staging/erofs/inode.c b/drivers/staging/erofs/inode.c
index 4f04f7c38cf2..924b8dfc7a8f 100644
--- a/drivers/staging/erofs/inode.c
+++ b/drivers/staging/erofs/inode.c
@@ -287,6 +287,7 @@ const struct inode_operations erofs_generic_iops = {
#ifdef CONFIG_EROFS_FS_XATTR
.listxattr = erofs_listxattr,
#endif
+ .get_acl = erofs_get_acl,
};
const struct inode_operations erofs_symlink_iops = {
@@ -294,6 +295,7 @@ const struct inode_operations erofs_symlink_iops = {
#ifdef CONFIG_EROFS_FS_XATTR
.listxattr = erofs_listxattr,
#endif
+ .get_acl = erofs_get_acl,
};
const struct inode_operations erofs_fast_symlink_iops = {
@@ -301,5 +303,6 @@ const struct inode_operations erofs_fast_symlink_iops = {
#ifdef CONFIG_EROFS_FS_XATTR
.listxattr = erofs_listxattr,
#endif
+ .get_acl = erofs_get_acl,
};
diff --git a/drivers/staging/erofs/namei.c b/drivers/staging/erofs/namei.c
index 7fed1f996ab0..b1752adc5934 100644
--- a/drivers/staging/erofs/namei.c
+++ b/drivers/staging/erofs/namei.c
@@ -238,5 +238,6 @@ const struct inode_operations erofs_dir_iops = {
#ifdef CONFIG_EROFS_FS_XATTR
.listxattr = erofs_listxattr,
#endif
+ .get_acl = erofs_get_acl,
};
diff --git a/drivers/staging/erofs/super.c b/drivers/staging/erofs/super.c
index 176fca2af379..15c784fba879 100644
--- a/drivers/staging/erofs/super.c
+++ b/drivers/staging/erofs/super.c
@@ -398,6 +398,11 @@ static int erofs_read_super(struct super_block *sb,
if (!silent)
infoln("root inode @ nid %llu", ROOT_NID(sbi));
+ if (test_opt(sbi, POSIX_ACL))
+ sb->s_flags |= SB_POSIXACL;
+ else
+ sb->s_flags &= ~SB_POSIXACL;
+
#ifdef CONFIG_EROFS_FS_ZIP
INIT_RADIX_TREE(&sbi->workstn_tree, GFP_ATOMIC);
#endif
@@ -646,6 +651,11 @@ static int erofs_remount(struct super_block *sb, int *flags, char *data)
if (err)
goto out;
+ if (test_opt(sbi, POSIX_ACL))
+ sb->s_flags |= SB_POSIXACL;
+ else
+ sb->s_flags &= ~SB_POSIXACL;
+
*flags |= SB_RDONLY;
return 0;
out:
diff --git a/drivers/staging/erofs/xattr.c b/drivers/staging/erofs/xattr.c
index 7de46690d972..e748df8d2b44 100644
--- a/drivers/staging/erofs/xattr.c
+++ b/drivers/staging/erofs/xattr.c
@@ -643,3 +643,40 @@ ssize_t erofs_listxattr(struct dentry *dentry,
return shared_listxattr(&it);
}
+#ifdef CONFIG_EROFS_FS_POSIX_ACL
+struct posix_acl *erofs_get_acl(struct inode *inode, int type)
+{
+ struct posix_acl *acl;
+ int prefix, rc;
+ char *value = NULL;
+
+ switch (type) {
+ case ACL_TYPE_ACCESS:
+ prefix = EROFS_XATTR_INDEX_POSIX_ACL_ACCESS;
+ break;
+ case ACL_TYPE_DEFAULT:
+ prefix = EROFS_XATTR_INDEX_POSIX_ACL_DEFAULT;
+ break;
+ default:
+ return ERR_PTR(-EINVAL);
+ }
+
+ rc = erofs_getxattr(inode, prefix, "", NULL, 0);
+ if (rc > 0) {
+ value = kmalloc(rc, GFP_KERNEL);
+ if (!value)
+ return ERR_PTR(-ENOMEM);
+ rc = erofs_getxattr(inode, prefix, "", value, rc);
+ }
+
+ if (rc == -ENOATTR)
+ acl = NULL;
+ else if (rc < 0)
+ acl = ERR_PTR(rc);
+ else
+ acl = posix_acl_from_xattr(&init_user_ns, value, rc);
+ kfree(value);
+ return acl;
+}
+#endif
+
diff --git a/drivers/staging/erofs/xattr.h b/drivers/staging/erofs/xattr.h
index 634dae9aaa0b..35ba5ac2139a 100644
--- a/drivers/staging/erofs/xattr.h
+++ b/drivers/staging/erofs/xattr.h
@@ -87,5 +87,11 @@ static ssize_t __maybe_unused erofs_listxattr(struct dentry *dentry,
}
#endif
+#ifdef CONFIG_EROFS_FS_POSIX_ACL
+struct posix_acl *erofs_get_acl(struct inode *inode, int type);
+#else
+#define erofs_get_acl (NULL)
+#endif
+
#endif
--
2.14.4
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