Commit b8862a09 authored by Christoph Hellwig's avatar Christoph Hellwig Committed by Carlos Maiolino
Browse files

xfs: don't validate error tags in the I/O path 



We can trust XFS developers enough to not pass random stuff to
XFS_ERROR_TEST/DELAY.  Open code the validity check in xfs_errortag_add,
which is the only place that receives unvalidated error tag values from
user space, and drop the now pointless xfs_errortag_enabled helper.

Signed-off-by: default avatarChristoph Hellwig <hch@lst.de>
Reviewed-by: default avatarHans Holmberg <hans.holmberg@wdc.com>
Reviewed-by: default avatarCarlos Maiolino <cmaiolino@redhat.com>
Reviewed-by: default avatarDarrick J. Wong <djwong@kernel.org>
Signed-off-by: default avatarCarlos Maiolino <cem@kernel.org>
parent 394969e2

fs/xfs/libxfs/xfs_errortag.h

+1 −1
Original line number Diff line number Diff line
@@ -53,7 +53,7 @@ 
 * Drop-writes support removed because write error handling cannot trash

 * pre-existing delalloc extents in any useful way anymore. We retain the

 * definition so that we can reject it as an invalid value in

 * xfs_errortag_valid().

 * xfs_errortag_add().

 */

#define XFS_ERRTAG_DROP_WRITES				28

#define XFS_ERRTAG_LOG_BAD_CRC				29

fs/xfs/xfs_error.c

+10 −28
Original line number Diff line number Diff line
@@ -125,30 +125,6 @@ xfs_errortag_del( 
	xfs_sysfs_del(&mp->m_errortag_kobj);

}



static bool

xfs_errortag_valid(

	unsigned int		error_tag)

{

	if (error_tag >= XFS_ERRTAG_MAX)

		return false;



	/* Error out removed injection types */

	if (error_tag == XFS_ERRTAG_DROP_WRITES)

		return false;

	return true;

}



bool

xfs_errortag_enabled(

	struct xfs_mount	*mp,

	unsigned int		tag)

{

	if (!xfs_errortag_valid(tag))

		return false;



	return mp->m_errortag[tag] != 0;

}



bool

xfs_errortag_test(

	struct xfs_mount	*mp,
@@ -158,9 +134,6 @@ xfs_errortag_test( 
{

	unsigned int		randfactor;



	if (!xfs_errortag_valid(error_tag))

		return false;



	randfactor = mp->m_errortag[error_tag];

	if (!randfactor || get_random_u32_below(randfactor))

		return false;
@@ -178,8 +151,17 @@ xfs_errortag_add( 
{

	BUILD_BUG_ON(ARRAY_SIZE(xfs_errortag_random_default) != XFS_ERRTAG_MAX);



	if (!xfs_errortag_valid(error_tag))

	if (error_tag >= XFS_ERRTAG_MAX)

		return -EINVAL;



	/* Error out removed injection types */

	switch (error_tag) {

	case XFS_ERRTAG_DROP_WRITES:

		return -EINVAL;

	default:

		break;

	}



	mp->m_errortag[error_tag] = xfs_errortag_random_default[error_tag];

	return 0;

}

fs/xfs/xfs_error.h

+1 −1
Original line number Diff line number Diff line
@@ -44,7 +44,7 @@ bool xfs_errortag_enabled(struct xfs_mount *mp, unsigned int tag); 
#define XFS_ERRORTAG_DELAY(mp, tag)		\

	do { \

		might_sleep(); \

		if (!xfs_errortag_enabled((mp), (tag))) \

		if (!mp->m_errortag[tag]) \

			break; \

		xfs_warn_ratelimited((mp), \

"Injecting %ums delay at file %s, line %d, on filesystem \"%s\"", \