Commit a10c4c5e authored by Al Viro's avatar Al Viro
Browse files

new helper: import_xattr_name() 



common logics for marshalling xattr names.

Reviewed-by: default avatarChristian Brauner <brauner@kernel.org>
Signed-off-by: default avatarAl Viro <viro@zeniv.linux.org.uk>
parent 537c7662

fs/internal.h

+3 −0
Original line number Diff line number Diff line
@@ -288,6 +288,9 @@ ssize_t do_getxattr(struct mnt_idmap *idmap, 
int setxattr_copy(const char __user *name, struct kernel_xattr_ctx *ctx);

int do_setxattr(struct mnt_idmap *idmap, struct dentry *dentry,

		struct kernel_xattr_ctx *ctx);



int import_xattr_name(struct xattr_name *kname, const char __user *name);



int may_write_xattr(struct mnt_idmap *idmap, struct inode *inode);



#ifdef CONFIG_FS_POSIX_ACL

fs/xattr.c

+23 −22
Original line number Diff line number Diff line
@@ -586,6 +586,17 @@ vfs_removexattr(struct mnt_idmap *idmap, struct dentry *dentry, 
}

EXPORT_SYMBOL_GPL(vfs_removexattr);



int import_xattr_name(struct xattr_name *kname, const char __user *name)

{

	int error = strncpy_from_user(kname->name, name,

					sizeof(kname->name));

	if (error == 0 || error == sizeof(kname->name))

		return -ERANGE;

	if (error < 0)

		return error;

	return 0;

}



/*

 * Extended attribute SET operations

 */
@@ -597,14 +608,10 @@ int setxattr_copy(const char __user *name, struct kernel_xattr_ctx *ctx) 
	if (ctx->flags & ~(XATTR_CREATE|XATTR_REPLACE))

		return -EINVAL;



	error = strncpy_from_user(ctx->kname->name, name,

				sizeof(ctx->kname->name));

	if (error == 0 || error == sizeof(ctx->kname->name))

		return  -ERANGE;

	if (error < 0)

	error = import_xattr_name(ctx->kname, name);

	if (error)

		return error;



	error = 0;

	if (ctx->size) {

		if (ctx->size > XATTR_SIZE_MAX)

			return -E2BIG;
@@ -763,10 +770,8 @@ getxattr(struct mnt_idmap *idmap, struct dentry *d, 
		.flags    = 0,

	};



	error = strncpy_from_user(kname.name, name, sizeof(kname.name));

	if (error == 0 || error == sizeof(kname.name))

		error = -ERANGE;

	if (error < 0)

	error = import_xattr_name(&kname, name);

	if (error)

		return error;



	error =  do_getxattr(idmap, d, &ctx);
@@ -906,12 +911,10 @@ static int path_removexattr(const char __user *pathname, 
{

	struct path path;

	int error;

	char kname[XATTR_NAME_MAX + 1];

	struct xattr_name kname;



	error = strncpy_from_user(kname, name, sizeof(kname));

	if (error == 0 || error == sizeof(kname))

		error = -ERANGE;

	if (error < 0)

	error = import_xattr_name(&kname, name);

	if (error)

		return error;

retry:

	error = user_path_at(AT_FDCWD, pathname, lookup_flags, &path);
@@ -919,7 +922,7 @@ static int path_removexattr(const char __user *pathname, 
		return error;

	error = mnt_want_write(path.mnt);

	if (!error) {

		error = removexattr(mnt_idmap(path.mnt), path.dentry, kname);

		error = removexattr(mnt_idmap(path.mnt), path.dentry, kname.name);

		mnt_drop_write(path.mnt);

	}

	path_put(&path);
@@ -945,23 +948,21 @@ SYSCALL_DEFINE2(lremovexattr, const char __user *, pathname, 
SYSCALL_DEFINE2(fremovexattr, int, fd, const char __user *, name)

{

	CLASS(fd, f)(fd);

	char kname[XATTR_NAME_MAX + 1];

	struct xattr_name kname;

	int error;



	if (fd_empty(f))

		return -EBADF;

	audit_file(fd_file(f));



	error = strncpy_from_user(kname, name, sizeof(kname));

	if (error == 0 || error == sizeof(kname))

		error = -ERANGE;

	if (error < 0)

	error = import_xattr_name(&kname, name);

	if (error)

		return error;



	error = mnt_want_write_file(fd_file(f));

	if (!error) {

		error = removexattr(file_mnt_idmap(fd_file(f)),

				    fd_file(f)->f_path.dentry, kname);

				    fd_file(f)->f_path.dentry, kname.name);

		mnt_drop_write_file(fd_file(f));

	}

	return error;

io_uring/xattr.c

+2 −5
Original line number Diff line number Diff line
@@ -62,11 +62,8 @@ static int __io_getxattr_prep(struct io_kiocb *req, 
	if (!ix->ctx.kname)

		return -ENOMEM;



	ret = strncpy_from_user(ix->ctx.kname->name, name,

				sizeof(ix->ctx.kname->name));

	if (!ret || ret == sizeof(ix->ctx.kname->name))

		ret = -ERANGE;

	if (ret < 0) {

	ret = import_xattr_name(ix->ctx.kname, name);

	if (ret) {

		kfree(ix->ctx.kname);

		return ret;

	}