From: "Darrick J. Wong" <djwong@xxxxxxxxxx>
[ Upstream commit e14293803f4e84eb23a417b462b56251033b5a66 ]
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: Leah Rumancik <leah.rumancik@xxxxxxxxx>
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
@@ -71,16 +71,29 @@ xfs_rtfree_extent(
int xfs_rtfree_blocks(struct xfs_trans *tp, xfs_fsblock_t rtbno,
xfs_filblks_t rtlen);
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)
# define xfs_rtalloc_query_range(m,t,l,h,f,p) (-ENOSYS)
# define xfs_rtalloc_query_all(m,t,f,p) (-ENOSYS)
# 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 6b87b04d0c6c..04247d1c7523 100644
--- a/fs/xfs/libxfs/xfs_sb.c
+++ b/fs/xfs/libxfs/xfs_sb.c
@@ -500,11 +500,12 @@ xfs_validate_sb_common(
rexts = div_u64(sbp->sb_rblocks, sbp->sb_rextsize);
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,
"realtime geometry sanity check failed");
return -EFSCORRUPTED;
diff --git a/fs/xfs/xfs_rtalloc.c b/fs/xfs/xfs_rtalloc.c
index eca800e2b879..2dcd5cca4ec2 100644
--- a/fs/xfs/xfs_rtalloc.c
+++ b/fs/xfs/xfs_rtalloc.c
@@ -996,10 +996,12 @@ xfs_growfs_rt(
/*
* Calculate new parameters. These are the final values to be reached.
*/
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;
nrsumsize = (uint)sizeof(xfs_suminfo_t) * nrsumlevels * nrbmblocks;
nrsumblocks = XFS_B_TO_FSB(mp, nrsumsize);
--
2.49.0.rc1.451.g8f38331e32-goog
