bcache: Fix a journal replay bug

journal replay wansn't validating pointers with bch_extent_invalid() before
derefing, fixed
Signed-off-by: Kent Overstreet <kmo@daterainc.com>

drivers/md/bcache/extents.c

@@ -474,9 +474,8 @@ static bool bch_extent_insert_fixup(struct btree_keys *b,
 	return false;
 }
 
-static bool bch_extent_invalid(struct btree_keys *bk, const struct bkey *k)
+bool __bch_extent_invalid(struct cache_set *c, const struct bkey *k)
 {
-	struct btree *b = container_of(bk, struct btree, keys);
 	char buf[80];
 
 	if (!KEY_SIZE(k))
@@ -485,16 +484,22 @@ static bool bch_extent_invalid(struct btree_keys *bk, const struct bkey *k)
 	if (KEY_SIZE(k) > KEY_OFFSET(k))
 		goto bad;
 
-	if (__ptr_invalid(b->c, k))
+	if (__ptr_invalid(c, k))
 		goto bad;
 
 	return false;
 bad:
 	bch_extent_to_text(buf, sizeof(buf), k);
-	cache_bug(b->c, "spotted extent %s: %s", buf, bch_ptr_status(b->c, k));
+	cache_bug(c, "spotted extent %s: %s", buf, bch_ptr_status(c, k));
 	return true;
 }
 
+static bool bch_extent_invalid(struct btree_keys *bk, const struct bkey *k)
+{
+	struct btree *b = container_of(bk, struct btree, keys);
+	return __bch_extent_invalid(b->c, k);
+}
+
 static bool bch_extent_bad_expensive(struct btree *b, const struct bkey *k,
 				     unsigned ptr)
 {

drivers/md/bcache/extents.h

@@ -9,5 +9,6 @@ struct cache_set;
 
 void bch_extent_to_text(char *, size_t, const struct bkey *);
 bool __bch_btree_ptr_invalid(struct cache_set *, const struct bkey *);
+bool __bch_extent_invalid(struct cache_set *, const struct bkey *);
 
 #endif /* _BCACHE_EXTENTS_H */

drivers/md/bcache/journal.c

@@ -7,6 +7,7 @@
 #include "bcache.h"
 #include "btree.h"
 #include "debug.h"
+#include "extents.h"
 
 #include <trace/events/bcache.h>
 
@@ -291,7 +292,8 @@ void bch_journal_mark(struct cache_set *c, struct list_head *list)
 
 		for (k = i->j.start;
 		     k < bset_bkey_last(&i->j);
-		     k = bkey_next(k)) {
+		     k = bkey_next(k))
+			if (!__bch_extent_invalid(c, k)) {
 				unsigned j;
 
 				for (j = 0; j < KEY_PTRS(k); j++)