xfs: dquot recovery does not validate the recovered dquot

[ Upstream commit 9c235df ]

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>
Signed-off-by: Leah Rumancik <leah.rumancik@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Author: Darrick J. Wong

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;