fs: split off do_getxattr from getxattr
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>
Link: https://lore.kernel.org/r/20220323154420.3301504-3-shr@fb.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
diff --git a/fs/internal.h b/fs/internal.h
index 5fb219f..9a6c233 100644
--- a/fs/internal.h
+++ b/fs/internal.h
@@ -212,6 +212,11 @@ struct xattr_ctx {
unsigned int flags;
};
+
+ssize_t do_getxattr(struct user_namespace *mnt_userns,
+ struct dentry *d,
+ struct xattr_ctx *ctx);
+
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 7117cb2..e8dd03e 100644
--- a/fs/xattr.c
+++ b/fs/xattr.c
@@ -676,44 +676,61 @@ 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,
+ struct xattr_ctx *ctx)
{
ssize_t error;
- void *kvalue = NULL;
- char kname[XATTR_NAME_MAX + 1];
+ char *kname = ctx->kname->name;
- error = strncpy_from_user(kname, name, sizeof(kname));
- if (error == 0 || error == sizeof(kname))
- error = -ERANGE;
- if (error < 0)
- return error;
-
- if (size) {
- if (size > XATTR_SIZE_MAX)
- size = XATTR_SIZE_MAX;
- kvalue = kvzalloc(size, GFP_KERNEL);
- if (!kvalue)
+ if (ctx->size) {
+ if (ctx->size > XATTR_SIZE_MAX)
+ ctx->size = XATTR_SIZE_MAX;
+ ctx->kvalue = kvzalloc(ctx->size, GFP_KERNEL);
+ if (!ctx->kvalue)
return -ENOMEM;
}
- error = vfs_getxattr(mnt_userns, d, kname, kvalue, size);
+ error = vfs_getxattr(mnt_userns, d, kname, ctx->kvalue, ctx->size);
if (error > 0) {
if ((strcmp(kname, XATTR_NAME_POSIX_ACL_ACCESS) == 0) ||
(strcmp(kname, XATTR_NAME_POSIX_ACL_DEFAULT) == 0))
posix_acl_fix_xattr_to_user(mnt_userns, d_inode(d),
- kvalue, error);
- if (size && copy_to_user(value, kvalue, error))
+ ctx->kvalue, error);
+ if (ctx->size && copy_to_user(ctx->value, ctx->kvalue, error))
error = -EFAULT;
- } else if (error == -ERANGE && size >= XATTR_SIZE_MAX) {
+ } else if (error == -ERANGE && ctx->size >= XATTR_SIZE_MAX) {
/* The file system tried to returned a value bigger
than XATTR_SIZE_MAX bytes. Not possible. */
error = -E2BIG;
}
- 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;
+ struct xattr_ctx ctx = {
+ .value = value,
+ .kvalue = NULL,
+ .size = size,
+ .kname = &kname,
+ .flags = 0,
+ };
+
+ error = strncpy_from_user(kname.name, name, sizeof(kname.name));
+ if (error == 0 || error == sizeof(kname.name))
+ error = -ERANGE;
+ if (error < 0)
+ return error;
+
+ error = do_getxattr(mnt_userns, d, &ctx);
+
+ kvfree(ctx.kvalue);
return error;
}