[PATCH v1 3/5] fs: split off the vfs_getxattr from getxattr

Stefan Roesch
2021-11-29T22:13:04Z

Summary:

This splits off vfs_getxattr call from the getxattr
function. This will allow io_uring to call it from
its io worker.

Signed-off-by: Stefan Roesch <shr@fb.com>
---
fs/internal.h | 6 ++++++
fs/xattr.c | 37 +++++++++++++++++++++++--------------
2 files changed, 29 insertions(+), 14 deletions(-)

diff --git a/fs/internal.h b/fs/internal.h
index c5c82bfb5ecf..9805415b199c 100644
--- a/fs/internal.h
+++ b/fs/internal.h
@@ -208,6 +208,12 @@ struct xattr_ctx {
int flags;
};

+ssize_t do_getxattr(struct user_namespace *mnt_userns,
+ struct dentry *d,
+ const char *kname,
+ void __user *value,
+ size_t size);
+
void *setxattr_setup(struct user_namespace *mnt_userns,
const char __user *name,
struct xattr_ctx *data);
diff --git a/fs/xattr.c b/fs/xattr.c
index 13963b914ac5..9e1dba601a03 100644
--- a/fs/xattr.c
+++ b/fs/xattr.c
@@ -666,19 +666,12 @@ SYSCALL_DEFINE5(fsetxattr, int, fd, const char __user *, name,
/*
* Extended attribute GET operations
*/
-static ssize_t
-getxattr(struct user_namespace *mnt_userns, struct dentry *d,
- const char __user *name, void __user *value, size_t size)
+ssize_t
+do_getxattr(struct user_namespace *mnt_userns, struct dentry *d,
+ const char *name, void __user *value, size_t size)
{
- ssize_t error;
void *kvalue = NULL;
- char kname[XATTR_NAME_MAX + 1];
-
- error = strncpy_from_user(kname, name, sizeof(kname));
- if (error == 0 || error == sizeof(kname))
- error = -ERANGE;
- if (error < 0)
- return error;
+ size_t error;

if (size) {
if (size > XATTR_SIZE_MAX)
@@ -688,10 +681,10 @@ getxattr(struct user_namespace *mnt_userns, struct dentry *d,
return -ENOMEM;
}

- error = vfs_getxattr(mnt_userns, d, kname, kvalue, size);
+ error = vfs_getxattr(mnt_userns, d, name, kvalue, size);
if (error > 0) {
- if ((strcmp(kname, XATTR_NAME_POSIX_ACL_ACCESS) == 0) ||
- (strcmp(kname, XATTR_NAME_POSIX_ACL_DEFAULT) == 0))
+ if ((strcmp(name, XATTR_NAME_POSIX_ACL_ACCESS) == 0) ||
+ (strcmp(name, XATTR_NAME_POSIX_ACL_DEFAULT) == 0))
posix_acl_fix_xattr_to_user(mnt_userns, kvalue, error);
if (size && copy_to_user(value, kvalue, error))
error = -EFAULT;
@@ -706,6 +699,22 @@ getxattr(struct user_namespace *mnt_userns, struct dentry *d,
return error;
}

+static ssize_t
+getxattr(struct user_namespace *mnt_userns, struct dentry *d,
+ const char __user *name, void __user *value, size_t size)
+{
+ ssize_t error;
+ char kname[XATTR_NAME_MAX + 1];
+
+ error = strncpy_from_user(kname, name, sizeof(kname));
+ if (error == 0 || error == sizeof(kname))
+ error = -ERANGE;
+ if (error < 0)
+ return error;
+
+ return do_getxattr(mnt_userns, d, kname, value, size);
+}
+
static ssize_t path_getxattr(const char __user *pathname,
const char __user *name, void __user *value,
size_t size, unsigned int lookup_flags)
--
2.30.2