Commit e1429380 authored by Darrick J. Wong's avatar Darrick J. Wong
Browse files

xfs: don't allow overly small or large realtime volumes 



Don't allow realtime volumes that are less than one rt extent long.
This has been broken across 4 LTS kernels with nobody noticing, so let's
just disable it.

Signed-off-by: default avatarDarrick J. Wong <djwong@kernel.org>
Reviewed-by: default avatarChristoph Hellwig <hch@lst.de>
parent cf8f0e6c

fs/xfs/libxfs/xfs_rtbitmap.h

+13 −0
Original line number Diff line number Diff line
@@ -353,6 +353,18 @@ int xfs_rtfree_blocks(struct xfs_trans *tp, xfs_fsblock_t rtbno, 


uint8_t xfs_compute_rextslog(xfs_rtbxlen_t rtextents);



/* Do we support an rt volume having this number of rtextents? */

static inline bool

xfs_validate_rtextents(

	xfs_rtbxlen_t		rtextents)

{

	/* No runt rt volumes */

	if (rtextents == 0)

		return false;



	return true;

}



xfs_filblks_t xfs_rtbitmap_blockcount(struct xfs_mount *mp, xfs_rtbxlen_t

		rtextents);

unsigned long long xfs_rtbitmap_wordcount(struct xfs_mount *mp,
@@ -372,6 +384,7 @@ unsigned long long xfs_rtsummary_wordcount(struct xfs_mount *mp, 
# define xfs_rtbuf_cache_relse(a)			(0)

# define xfs_rtalloc_extent_is_free(m,t,s,l,i)		(-ENOSYS)

# define xfs_compute_rextslog(rtx)			(0)

# define xfs_validate_rtextents(rtx)			(false)

static inline xfs_filblks_t

xfs_rtbitmap_blockcount(struct xfs_mount *mp, xfs_rtbxlen_t rtextents)

{

fs/xfs/libxfs/xfs_sb.c

+2 −1
Original line number Diff line number Diff line
@@ -509,7 +509,8 @@ xfs_validate_sb_common( 
		rbmblocks = howmany_64(sbp->sb_rextents,

				       NBBY * sbp->sb_blocksize);



		if (sbp->sb_rextents != rexts ||

		if (!xfs_validate_rtextents(rexts) ||

		    sbp->sb_rextents != rexts ||

		    sbp->sb_rextslog != xfs_compute_rextslog(rexts) ||

		    sbp->sb_rbmblocks != rbmblocks) {

			xfs_notice(mp,

fs/xfs/xfs_rtalloc.c

+2 −0
Original line number Diff line number Diff line
@@ -963,6 +963,8 @@ xfs_growfs_rt( 
	 */

	nrextents = nrblocks;

	do_div(nrextents, in->extsize);

	if (!xfs_validate_rtextents(nrextents))

		return -EINVAL;

	nrbmblocks = xfs_rtbitmap_blockcount(mp, nrextents);

	nrextslog = xfs_compute_rextslog(nrextents);

	nrsumlevels = nrextslog + 1;