diff mbox series

[2/4] libxfs: add more bounds checking to sb sanity checks

Message ID 153300935012.5164.595072325880690471.stgit@magnolia (mailing list archive)
State Accepted
Headers show
Series xfs-4.19: superblock verifier cleanups | expand

Commit Message

Darrick J. Wong July 31, 2018, 3:55 a.m. UTC 
From: Bill O'Donnell <billodo@redhat.com>

Current sb verifier doesn't check bounds on sb_fdblocks and sb_ifree.
Add sanity checks for these parameters.

Signed-off-by: Bill O'Donnell <billodo@redhat.com>
[darrick: port to refactored sb validation predicates]
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Eric Sandeen <sandeen@redhat.com>
---
 fs/xfs/libxfs/xfs_sb.c |   12 ++++++++++++
 1 file changed, 12 insertions(+)



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diff mbox series

Patch

diff --git a/fs/xfs/libxfs/xfs_sb.c b/fs/xfs/libxfs/xfs_sb.c
index f3835e923893..3d29f4a5242f 100644
--- a/fs/xfs/libxfs/xfs_sb.c
+++ b/fs/xfs/libxfs/xfs_sb.c
@@ -150,6 +150,18 @@  xfs_validate_sb_write(
 	struct xfs_mount	*mp,
 	struct xfs_sb		*sbp)
 {
+	/*
+	 * Carry out additional sb summary counter sanity checks when we write
+	 * the superblock.  We skip this in the read validator because there
+	 * could be newer superblocks in the log and if the values are garbage
+	 * we'll recalculate them at the end of log mount.
+	 */
+	if (sbp->sb_fdblocks > sbp->sb_dblocks ||
+	    sbp->sb_ifree > sbp->sb_icount) {
+		xfs_warn(mp, "SB summary counter sanity check failed");
+		return -EFSCORRUPTED;
+	}
+
 	if (XFS_SB_VERSION_NUM(sbp) != XFS_SB_VERSION_5)
 		return 0;