xfs: dquot recovery does not validate the recovered dquot

When we're recovering ondisk quota records from the log, we need to
validate the recovered buffer contents before writing them to disk.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Chandan Babu R <chandanbabu@kernel.org>

fs/xfs/xfs_dquot_item_recover.c

@@ -19,6 +19,7 @@
 #include "xfs_log.h"
 #include "xfs_log_priv.h"
 #include "xfs_log_recover.h"
+#include "xfs_error.h"
 
 STATIC void
 xlog_recover_dquot_ra_pass2(
@@ -152,6 +153,19 @@ xlog_recover_dquot_commit_pass2(
 				 XFS_DQUOT_CRC_OFF);
 	}
 
+	/* Validate the recovered dquot. */
+	fa = xfs_dqblk_verify(log->l_mp, dqb, dq_f->qlf_id);
+	if (fa) {
+		XFS_CORRUPTION_ERROR("Bad dquot after recovery",
+				XFS_ERRLEVEL_LOW, mp, dqb,
+				sizeof(struct xfs_dqblk));
+		xfs_alert(mp,
+ "Metadata corruption detected at %pS, dquot 0x%x",
+				fa, dq_f->qlf_id);
+		error = -EFSCORRUPTED;
+		goto out_release;
+	}
+
 	ASSERT(dq_f->qlf_size == 2);
 	ASSERT(bp->b_mount == mp);
 	bp->b_flags |= _XBF_LOGRECOVERY;