Commit 9c9d1896 authored by Linus Torvalds's avatar Linus Torvalds
Browse files

Merge tag 'lsm-pr-20220829' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/lsm 

Pull LSM support for IORING_OP_URING_CMD from Paul Moore:
 "Add SELinux and Smack controls to the io_uring IORING_OP_URING_CMD.

  These are necessary as without them the IORING_OP_URING_CMD remains
  outside the purview of the LSMs (Luis' LSM patch, Casey's Smack patch,
  and my SELinux patch). They have been discussed at length with the
  io_uring folks, and Jens has given his thumbs-up on the relevant
  patches (see the commit descriptions).

  There is one patch that is not strictly necessary, but it makes
  testing much easier and is very trivial: the /dev/null
  IORING_OP_URING_CMD patch."

* tag 'lsm-pr-20220829' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/lsm:
  Smack: Provide read control for io_uring_cmd
  /dev/null: add IORING_OP_URING_CMD support
  selinux: implement the security_uring_cmd() LSM hook
  lsm,io_uring: add LSM hooks for the new uring_cmd file op
parents dcf8e563 dd937340

drivers/char/mem.c

+6 −0
Original line number Diff line number Diff line
@@ -480,6 +480,11 @@ static ssize_t splice_write_null(struct pipe_inode_info *pipe, struct file *out, 
	return splice_from_pipe(pipe, out, ppos, len, flags, pipe_to_null);

}



static int uring_cmd_null(struct io_uring_cmd *ioucmd, unsigned int issue_flags)

{

	return 0;

}



static ssize_t read_iter_zero(struct kiocb *iocb, struct iov_iter *iter)

{

	size_t written = 0;
@@ -663,6 +668,7 @@ static const struct file_operations null_fops = { 
	.read_iter	= read_iter_null,

	.write_iter	= write_iter_null,

	.splice_write	= splice_write_null,

	.uring_cmd	= uring_cmd_null,

};



static const struct file_operations __maybe_unused port_fops = {

include/linux/lsm_hook_defs.h

+1 −0
Original line number Diff line number Diff line
@@ -407,4 +407,5 @@ LSM_HOOK(int, 0, perf_event_write, struct perf_event *event) 
#ifdef CONFIG_IO_URING

LSM_HOOK(int, 0, uring_override_creds, const struct cred *new)

LSM_HOOK(int, 0, uring_sqpoll, void)

LSM_HOOK(int, 0, uring_cmd, struct io_uring_cmd *ioucmd)

#endif /* CONFIG_IO_URING */

include/linux/lsm_hooks.h

+3 −0
Original line number Diff line number Diff line
@@ -1582,6 +1582,9 @@ 
 *      Check whether the current task is allowed to spawn a io_uring polling

 *      thread (IORING_SETUP_SQPOLL).

 *

 * @uring_cmd:

 *      Check whether the file_operations uring_cmd is allowed to run.

 *

 */

union security_list_options {

	#define LSM_HOOK(RET, DEFAULT, NAME, ...) RET (*NAME)(__VA_ARGS__);

include/linux/security.h

+5 −0
Original line number Diff line number Diff line
@@ -2060,6 +2060,7 @@ static inline int security_perf_event_write(struct perf_event *event) 
#ifdef CONFIG_SECURITY

extern int security_uring_override_creds(const struct cred *new);

extern int security_uring_sqpoll(void);

extern int security_uring_cmd(struct io_uring_cmd *ioucmd);

#else

static inline int security_uring_override_creds(const struct cred *new)

{
@@ -2069,6 +2070,10 @@ static inline int security_uring_sqpoll(void) 
{

	return 0;

}

static inline int security_uring_cmd(struct io_uring_cmd *ioucmd)

{

	return 0;

}

#endif /* CONFIG_SECURITY */

#endif /* CONFIG_IO_URING */

io_uring/uring_cmd.c

+5 −0
Original line number Diff line number Diff line
@@ -3,6 +3,7 @@ 
#include <linux/errno.h>

#include <linux/file.h>

#include <linux/io_uring.h>

#include <linux/security.h>



#include <uapi/linux/io_uring.h>
@@ -88,6 +89,10 @@ int io_uring_cmd(struct io_kiocb *req, unsigned int issue_flags) 
	if (!req->file->f_op->uring_cmd)

		return -EOPNOTSUPP;



	ret = security_uring_cmd(ioucmd);

	if (ret)

		return ret;



	if (ctx->flags & IORING_SETUP_SQE128)

		issue_flags |= IO_URING_F_SQE128;

	if (ctx->flags & IORING_SETUP_CQE32)