From: "Darrick J. Wong" <djwong@xxxxxxxxxx> commit e14293803f4e84eb23a417b462b56251033b5a66 upstream. [backport: resolve merge conflicts due to refactoring rtbitmap/summary macros and accessors] 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: Darrick J. Wong <djwong@xxxxxxxxxx> Reviewed-by: Christoph Hellwig <hch@xxxxxx> Signed-off-by: Catherine Hoang <catherine.hoang@xxxxxxxxxx> Acked-by: Darrick J. Wong <djwong@xxxxxxxxxx> --- fs/xfs/libxfs/xfs_rtbitmap.h | 13 +++++++++++++ fs/xfs/libxfs/xfs_sb.c | 3 ++- fs/xfs/xfs_rtalloc.c | 2 ++ 3 files changed, 17 insertions(+), 1 deletion(-) diff --git a/fs/xfs/libxfs/xfs_rtbitmap.h b/fs/xfs/libxfs/xfs_rtbitmap.h index 6becdc7a48ed..4e49aadf0955 100644 --- a/fs/xfs/libxfs/xfs_rtbitmap.h +++ b/fs/xfs/libxfs/xfs_rtbitmap.h @@ -73,6 +73,18 @@ 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; +} + #else /* CONFIG_XFS_RT */ # define xfs_rtfree_extent(t,b,l) (-ENOSYS) # define xfs_rtfree_blocks(t,rb,rl) (-ENOSYS) @@ -81,6 +93,7 @@ uint8_t xfs_compute_rextslog(xfs_rtbxlen_t rtextents); # define xfs_rtbuf_get(m,t,b,i,p) (-ENOSYS) # define xfs_rtalloc_extent_is_free(m,t,s,l,i) (-ENOSYS) # define xfs_compute_rextslog(rtx) (0) +# define xfs_validate_rtextents(rtx) (false) #endif /* CONFIG_XFS_RT */ #endif /* __XFS_RTBITMAP_H__ */ diff --git a/fs/xfs/libxfs/xfs_sb.c b/fs/xfs/libxfs/xfs_sb.c index 25eec54f9bb2..acba0694abf4 100644 --- a/fs/xfs/libxfs/xfs_sb.c +++ b/fs/xfs/libxfs/xfs_sb.c @@ -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, diff --git a/fs/xfs/xfs_rtalloc.c b/fs/xfs/xfs_rtalloc.c index 5fbe5e33c425..e5d6031d47bb 100644 --- a/fs/xfs/xfs_rtalloc.c +++ b/fs/xfs/xfs_rtalloc.c @@ -998,6 +998,8 @@ xfs_growfs_rt( */ nrextents = nrblocks; do_div(nrextents, in->extsize); + if (!xfs_validate_rtextents(nrextents)) + return -EINVAL; nrbmblocks = howmany_64(nrextents, NBBY * sbp->sb_blocksize); nrextslog = xfs_compute_rextslog(nrextents); nrsumlevels = nrextslog + 1; -- 2.39.3