From: Darrick J. Wong <darrick.wong@oracle.com>
Date: Fri, 1 May 2020 21:37:08 +0000 (-0400)
Subject: xfs: add a function to deal with corrupt buffers post-verifiers
X-Git-Tag: v5.7.0-rc0~27
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=1be76d11d03608ff8d0470c877da1d8f1ef3b018;p=thirdparty%2Fxfsprogs-dev.git

xfs: add a function to deal with corrupt buffers post-verifiers

Source kernel commit: 8d57c21600a514d7a9237327c2496ae159bab5bb

Add a helper function to get rid of buffers that we have decided are
corrupt after the verifiers have run.  This function is intended to
handle metadata checks that can't happen in the verifiers, such as
inter-block relationship checking.  Note that we now mark the buffer
stale so that it will not end up on any LRU and will be purged on
release.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Eric Sandeen <sandeen@sandeen.net>
---

diff --git a/libxfs/libxfs_priv.h b/libxfs/libxfs_priv.h
index 6533ccb53..120ff3dc6 100644
--- a/libxfs/libxfs_priv.h
+++ b/libxfs/libxfs_priv.h
@@ -383,6 +383,9 @@ static inline struct xfs_buf *xfs_buf_incore(struct xfs_buftarg *target,
 #define xfs_buf_zero(bp, off, len) \
 	memset((bp)->b_addr + off, 0, len);
 
+void __xfs_buf_mark_corrupt(struct xfs_buf *bp, xfs_failaddr_t fa);
+#define xfs_buf_mark_corrupt(bp) __xfs_buf_mark_corrupt((bp), __this_address)
+
 /* mount stuff */
 #define XFS_MOUNT_32BITINODES		LIBXFS_MOUNT_32BITINODES
 #define XFS_MOUNT_ATTR2			LIBXFS_MOUNT_ATTR2
diff --git a/libxfs/rdwr.c b/libxfs/rdwr.c
index fd6565120..a236a84b8 100644
--- a/libxfs/rdwr.c
+++ b/libxfs/rdwr.c
@@ -1618,3 +1618,25 @@ libxfs_buf_priority(
 {
 	return cache_node_get_priority(&bp->b_node);
 }
+
+/*
+ * Log a message about and stale a buffer that a caller has decided is corrupt.
+ *
+ * This function should be called for the kinds of metadata corruption that
+ * cannot be detect from a verifier, such as incorrect inter-block relationship
+ * data.  Do /not/ call this function from a verifier function.
+ *
+ * The buffer must be XBF_DONE prior to the call.  Afterwards, the buffer will
+ * be marked stale, but b_error will not be set.  The caller is responsible for
+ * releasing the buffer or fixing it.
+ */
+void
+__xfs_buf_mark_corrupt(
+	struct xfs_buf		*bp,
+	xfs_failaddr_t		fa)
+{
+	ASSERT(bp->b_flags & XBF_DONE);
+
+	xfs_buf_corruption_error(bp);
+	xfs_buf_stale(bp);
+}
diff --git a/libxfs/xfs_alloc.c b/libxfs/xfs_alloc.c
index b3abab493..fdd92da39 100644
--- a/libxfs/xfs_alloc.c
+++ b/libxfs/xfs_alloc.c
@@ -718,7 +718,7 @@ xfs_alloc_update_counters(
 	xfs_trans_agblocks_delta(tp, len);
 	if (unlikely(be32_to_cpu(agf->agf_freeblks) >
 		     be32_to_cpu(agf->agf_length))) {
-		xfs_buf_corruption_error(agbp);
+		xfs_buf_mark_corrupt(agbp);
 		return -EFSCORRUPTED;
 	}
 
diff --git a/libxfs/xfs_attr_leaf.c b/libxfs/xfs_attr_leaf.c
index edd01eef5..832979c99 100644
--- a/libxfs/xfs_attr_leaf.c
+++ b/libxfs/xfs_attr_leaf.c
@@ -2336,7 +2336,7 @@ xfs_attr3_leaf_lookup_int(
 	xfs_attr3_leaf_hdr_from_disk(args->geo, &ichdr, leaf);
 	entries = xfs_attr3_leaf_entryp(leaf);
 	if (ichdr.count >= args->geo->blksize / 8) {
-		xfs_buf_corruption_error(bp);
+		xfs_buf_mark_corrupt(bp);
 		return -EFSCORRUPTED;
 	}
 
@@ -2355,11 +2355,11 @@ xfs_attr3_leaf_lookup_int(
 			break;
 	}
 	if (!(probe >= 0 && (!ichdr.count || probe < ichdr.count))) {
-		xfs_buf_corruption_error(bp);
+		xfs_buf_mark_corrupt(bp);
 		return -EFSCORRUPTED;
 	}
 	if (!(span <= 4 || be32_to_cpu(entry->hashval) == hashval)) {
-		xfs_buf_corruption_error(bp);
+		xfs_buf_mark_corrupt(bp);
 		return -EFSCORRUPTED;
 	}
 
diff --git a/libxfs/xfs_btree.c b/libxfs/xfs_btree.c
index 57862dfad..51be86e48 100644
--- a/libxfs/xfs_btree.c
+++ b/libxfs/xfs_btree.c
@@ -1759,7 +1759,7 @@ xfs_btree_lookup_get_block(
 
 out_bad:
 	*blkp = NULL;
-	xfs_buf_corruption_error(bp);
+	xfs_buf_mark_corrupt(bp);
 	xfs_trans_brelse(cur->bc_tp, bp);
 	return -EFSCORRUPTED;
 }
diff --git a/libxfs/xfs_da_btree.c b/libxfs/xfs_da_btree.c
index 7f26d1243..d785312fc 100644
--- a/libxfs/xfs_da_btree.c
+++ b/libxfs/xfs_da_btree.c
@@ -587,7 +587,7 @@ xfs_da3_split(
 	node = oldblk->bp->b_addr;
 	if (node->hdr.info.forw) {
 		if (be32_to_cpu(node->hdr.info.forw) != addblk->blkno) {
-			xfs_buf_corruption_error(oldblk->bp);
+			xfs_buf_mark_corrupt(oldblk->bp);
 			error = -EFSCORRUPTED;
 			goto out;
 		}
@@ -600,7 +600,7 @@ xfs_da3_split(
 	node = oldblk->bp->b_addr;
 	if (node->hdr.info.back) {
 		if (be32_to_cpu(node->hdr.info.back) != addblk->blkno) {
-			xfs_buf_corruption_error(oldblk->bp);
+			xfs_buf_mark_corrupt(oldblk->bp);
 			error = -EFSCORRUPTED;
 			goto out;
 		}
@@ -1621,7 +1621,7 @@ xfs_da3_node_lookup_int(
 		}
 
 		if (magic != XFS_DA_NODE_MAGIC && magic != XFS_DA3_NODE_MAGIC) {
-			xfs_buf_corruption_error(blk->bp);
+			xfs_buf_mark_corrupt(blk->bp);
 			return -EFSCORRUPTED;
 		}
 
@@ -1636,7 +1636,7 @@ xfs_da3_node_lookup_int(
 
 		/* Tree taller than we can handle; bail out! */
 		if (nodehdr.level >= XFS_DA_NODE_MAXDEPTH) {
-			xfs_buf_corruption_error(blk->bp);
+			xfs_buf_mark_corrupt(blk->bp);
 			return -EFSCORRUPTED;
 		}
 
@@ -1644,7 +1644,7 @@ xfs_da3_node_lookup_int(
 		if (blkno == args->geo->leafblk)
 			expected_level = nodehdr.level - 1;
 		else if (expected_level != nodehdr.level) {
-			xfs_buf_corruption_error(blk->bp);
+			xfs_buf_mark_corrupt(blk->bp);
 			return -EFSCORRUPTED;
 		} else
 			expected_level--;
diff --git a/libxfs/xfs_dir2_leaf.c b/libxfs/xfs_dir2_leaf.c
index d73e54eb1..0cecd698f 100644
--- a/libxfs/xfs_dir2_leaf.c
+++ b/libxfs/xfs_dir2_leaf.c
@@ -1381,7 +1381,7 @@ xfs_dir2_leaf_removename(
 	ltp = xfs_dir2_leaf_tail_p(geo, leaf);
 	bestsp = xfs_dir2_leaf_bests_p(ltp);
 	if (be16_to_cpu(bestsp[db]) != oldbest) {
-		xfs_buf_corruption_error(lbp);
+		xfs_buf_mark_corrupt(lbp);
 		return -EFSCORRUPTED;
 	}
 	/*
diff --git a/libxfs/xfs_dir2_node.c b/libxfs/xfs_dir2_node.c
index ffa136b99..3dd999c3b 100644
--- a/libxfs/xfs_dir2_node.c
+++ b/libxfs/xfs_dir2_node.c
@@ -436,7 +436,7 @@ xfs_dir2_leaf_to_node(
 	ltp = xfs_dir2_leaf_tail_p(args->geo, leaf);
 	if (be32_to_cpu(ltp->bestcount) >
 				(uint)dp->i_d.di_size / args->geo->blksize) {
-		xfs_buf_corruption_error(lbp);
+		xfs_buf_mark_corrupt(lbp);
 		return -EFSCORRUPTED;
 	}
 
@@ -510,7 +510,7 @@ xfs_dir2_leafn_add(
 	 * into other peoples memory
 	 */
 	if (index < 0) {
-		xfs_buf_corruption_error(bp);
+		xfs_buf_mark_corrupt(bp);
 		return -EFSCORRUPTED;
 	}
 
@@ -797,7 +797,7 @@ xfs_dir2_leafn_lookup_for_entry(
 
 	xfs_dir3_leaf_check(dp, bp);
 	if (leafhdr.count <= 0) {
-		xfs_buf_corruption_error(bp);
+		xfs_buf_mark_corrupt(bp);
 		return -EFSCORRUPTED;
 	}