[PATCH v9 3/5] fs: split off do_getxattr from getxattr

Stefan Roesch
2021-12-28T18:42:05Z

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

Signed-off-by: Stefan Roesch <shr@fb.com>
Acked-by: Christian Brauner <christian.brauner@ubuntu.com>
---
fs/internal.h | 7 +++++++
fs/xattr.c | 32 ++++++++++++++++++++------------
2 files changed, 27 insertions(+), 12 deletions(-)

diff --git a/fs/internal.h b/fs/internal.h
index 00c98b0cd634..942b2005a2be 100644
--- a/fs/internal.h
+++ b/fs/internal.h
@@ -220,6 +220,13 @@ struct xattr_ctx {
unsigned int flags;
};

+
+ssize_t do_getxattr(struct user_namespace *mnt_userns,
+ struct dentry *d,
+ const char *kname,
+ void __user *value,
+ size_t size);
+
int setxattr_copy(const char __user *name, struct xattr_ctx *ctx);
int do_setxattr(struct user_namespace *mnt_userns, struct dentry *dentry,
struct xattr_ctx *ctx);
diff --git a/fs/xattr.c b/fs/xattr.c
index 923ba944d20e..3b6d683d07b9 100644
--- a/fs/xattr.c
+++ b/fs/xattr.c
@@ -677,19 +677,12 @@ 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 *kname, 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;
+ ssize_t error;

if (size) {
if (size > XATTR_SIZE_MAX)
@@ -713,10 +706,25 @@ getxattr(struct user_namespace *mnt_userns, struct dentry *d,
}

kvfree(kvalue);
-
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;
+ struct xattr_name kname;
+
+ error = strncpy_from_user(kname.name, name, sizeof(kname.name));
+ if (error == 0 || error == sizeof(kname.name))
+ error = -ERANGE;
+ if (error < 0)
+ return error;
+
+ return do_getxattr(mnt_userns, d, kname.name, 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